We know how long coronavirus survives on surfaces. Here’s what it means for handling money, food and more



Manuel Bruque/EPA

Ian M. Mackay, The University of Queensland and Katherine Arden, The University of Queensland

Like the other 200 or so respiratory viruses we know of, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the new coronavirus, infects the cells of our airways.

It causes a range of signs and symptoms, or none at all. It can spread easily from person-to-person, and can be coughed into the air and onto surfaces.

Viruses only replicate inside a living cell – outside the cell, they’re on a path to either infect us, or their own destruction. How long a virus survives outside a cell varies.

Researchers found SARS-CoV-2 remains infectious in airborne droplets for at least three hours. This doesn’t mean infected humans produce enough virus in a cough to infect another person, but they might.


Wes Mountain/The Conversation, CC BY-ND

We think the virus also spreads by touch. Hard, shiny surfaces such as plastic, stainless steel, benchtops, and likely glass can support infectious virus, expelled in droplets, for up to 72 hours. But the virus rapidly degrades during this time. On fibrous and absorbent surfaces such as cardboard, paper, fabric and hessian, it becomes inactive more quickly.

How can we reduce risk from surfaces and objects?

Frequently touched surfaces are all around us. Benches, handrails, door handles – they are in our homes, on our way to work, school, play, shop, and every other destination. There’s a risk of contaminating these surfaces if we touch them with virus-laden fingers, and a risk we’ll contract the virus from such surfaces.

Think of your hands as the enemy. Wash them well, and much more often than usual. Between hand-washing, avoid constantly touching the mucous membranes that lead to your airways. Basically, try not to rub your eyes, pick your nose, or touch your lips and mouth.




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Can I get coronavirus from mail or package deliveries? Should I disinfect my phone?


Taking precautions through small actions

We’re already seeing engineering initiatives to help combat the virus’s spread. In Sydney, pedestrian crossings have been automated so people can avoid touching the buttons.

To slow the spread of SARS-CoV-2, assume everything outside your home is potentially contaminated, and act accordingly. So don’t touch your face, sanitise frequently while you are out, and wash your hands and clean your phone once home.

While it’s best to stay home, keep these tips in mind if you must leave the house.

• Going shopping

Grocery shopping requires touching surfaces and items, including trolleys and baskets. Sometimes sanitiser or antibacterial wipes are available for hands and handles at the store entrance – but they’re often not, so bring your own (if you can get some). It probably doesn’t matter what type of bag you use, but have a plan for how to avoid bringing the virus into your home.

• Making payments

Cards and cash could transfer the virus to your hands. That said, card payment is probably lower risk because you retain the card and don’t have to touch other people. But wherever possible, contact-free bank transfers would pose the least risk.

• Handling and eating fresh and canned food

SARS-CoV-2 is inactivated at temperatures well below those required in the process of canning food, so canned food is free of it. For freshly packaged food, risk depends on whether the person doing the packing was sick or not. If you are concerned, stick with food that can be cooked, peeled or washed in mild soapy water, and thoroughly rinsed.




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While evidence is weak, we know soap and water should inactivate SARS-CoV-2 on food – but this will work better on foods with a shinier, harder outer surface, compared to foods that have been cut or have softer surfaces, such as strawberries and raspberries. If you decide to wash any food with soap, make sure all the soap is removed.

• At the park

Avoid equipment that is likely used a lot, including play equipment and water fountains. It would be safer to kick a ball around or play on the grass, rather than use swings. Sandpits hold horrors other than SARS-CoV-2.

• Takeaway and deliveries

When getting takeaway food, or for businesses offering it, avoid plastic containers and use more fibrous materials such as cardboard, paper and fabric for packaging. Researchers found no infectious SARS-CoV-2 on cardboard after 24 hours.

Also, avoid proximity to servers and delivery people, and opt for contactless delivery whenever you can.

• Public transport, escalators, elevators and bathrooms

Frequently touched hard, shiny surfaces such as lift buttons and handle bars in trams are a big risk, more so than fabric seats, or taking the stairs. Even the most high-tech overseas surface cleaning efforts are intermittent, so you’ll need to take responsibility for yourself. Also, after using public bathrooms, wash your hands well.

Calm and calculated

It’s important to be calm, realistic and not focus on single events or actions once you step outside. You can’t account for everything.

Think more about the risk of the entire task rather than the many small risks encountered during the process. A silver lining in taking such precautions is that you’ll also reduce your risk of catching the flu this season.

It’s also important to keep your home clean. You can use diluted bleach, detergents or alcohol solutions on surfaces. Queensland Health has more information.




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How to clean your house to prevent the spread of coronavirus and other infections


For items that are hard to clean, sunshine may be valuable. Leave your shoes outside, soles up, in the sun. Coronaviruses begin degrading quickly in temperatures higher than 56 degrees Celsius, and in direct UV light.

Ultimately, the best ways to avoid SARS-CoV-2 infection are primitive ones – sanitise your hands and stay away from others. Physical distancing remains the most effective measure to slow the progression of this pandemic.The Conversation

Ian M. Mackay, Adjunct assistant professor, The University of Queensland and Katherine Arden, Virologist, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Frozen, canned or fermented: when you can’t shop often for fresh vegetables, what are the best alternatives?



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Jesse Beasley, University of Melbourne; Kate Howell, University of Melbourne; Nathan M D’Cunha, University of Canberra; Nenad Naumovski, University of Canberra, and Senaka Ranadheera, University of Melbourne

If you’re trying to reduce your trips to the shops as you practise social distancing and contribute to “flattening the curve” of the coronavirus spread, you might be wondering what it means for your vegetable crisper.

Fresh vegetables need replacing often and, thanks to panic buying, there’s no guarantee you’ll find your favourite fresh foods in your local supermarket.

The good news is there are some really nutritious alternatives to fresh vegetables, and the old adage that “fresh is best” isn’t always true.

How to ‘flatten the curve’. Video by the Australian Academy of Science.

Even before coronavirus, vegetables were getting pricier

Fresh vegetable prices have been increasing on average 2% per year over the past decade.

In Australia, vegetable prices are expected to increase 20-50% over the coming months due to drought and the recent bushfires.

Cauliflower, broccoli, green leafy vegetables, and root vegetables such as potatoes and pumpkins are expected to be hardest hit.

We should therefore all be thinking of ways to maximise the shelf life of our fresh veggies. In addition, it’s important not to forget the value of frozen, canned and fermented alternatives.




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Don’t skip the veggies, even in a pandemic

Australian dietary guidelines recommend daily consumption of different types and colours of vegetables. However, these guidelines don’t say in what form these veggies should be eaten.

Fresh vegetables are at their most nutritious (and often cheapest) when they are recently harvested and in season, which is not always the case on supermarket shelves.

Long transport times and poor storage conditions can also reduce the nutritional quality of fresh vegetables.

The upshot is that frozen and fermented vegetables can provide the same nutrition as fresh alternatives, especially as they’re often harvested in season and snap-frozen or fermented soon after picking.

Whatever you choose, it’s important to remember vegetables are not only nutritious – they can also reduce the risk of cancer and improve your gut microbiome.

Frozen and fermented vegetables can provide the same nutrition as fresh alternatives.
Shutterstock

Fresh vs frozen vegetables

The shelf life of fresh vegetables is generally short (3-14 days) even when refrigerated. Freezing, on the other hand, can preserve the nutritional quality of vegetables and increase their shelf life to up to 12 months.

In some cases, frozen vegetables have a higher nutritional quality than fresh vegetables, particularly if there is a short time between harvesting and freezing.

Nevertheless, some nutrients such as B vitamins and vitamin C are vulnerable to the freezing process. One study found higher levels of vitamin C in fresh capsicum, carrot, parsley and spinach relative to frozen alternatives.

Variation in the freezing process, storage conditions and temperature can also change the quality of vegetables.

For example, ice crystals that form during freezing can damage the internal cell structure of potatoes and negatively affect their texture.

If you want to freeze vegetables yourself, select those that are fresh, undamaged and in season and blanch them quickly before freezing. This helps retain colour, flavour and nutritional quality.

Some vegetables such as tomato, capsicum and corn do not need to be blanched before freezing.

Blanching and freezing fresh veggies is a great way to improve shelf life.
Shutterstock

Canned and fermented vegetables

Canning and/or fermentation can extend the shelf life of vegetables to between one and five years.

Canned vegetables generally have a similar nutritional profile to fresh vegetables, particularly when it comes to minerals and fibre. However, certain steps in the process (such as peeling) may lead to some nutritional loss.

Just remember that once opened, canned vegetables should be stored in a separate container and consumed within three days.

Fermented vegetables such as kimchi and sauerkraut not only taste delicious, they have a range of health benefits and are packed with beneficial probiotics.

During fermentation, microorganisms convert the carbohydrates in veggies into alcohol and/or acids that act as natural preservatives (extending shelf life) and can improve the digestibility of starch and protein.

Fermented vegetables are also full of antioxidants and adding extra ingredients like ginger, chilli and garlic can make them an even more nutritious choice.

To reap the full benefits, ferment veggies yourself or choose refrigerated fermented vegetables at the shops (unrefrigerated versions are pasteurised and can have lower probiotic benefits).

Keep calm and eat veggies

Vegetables are a great source of essential nutrients and Australians should aim to eat a wide variety of them each day.

By including fresh, frozen, canned and fermented vegetables in our diet, we not only give our bodies a boost, but help to take pressure off Australian growers to produce high quality and seasonal vegetables all year round.

The vast majority of Australians don’t eat enough vegetables, and these nutritious and tasty alternatives could be the key to improving our overall health – at a time when we need it most.The Conversation

Jesse Beasley, PhD Student in BioSciences, University of Melbourne; Kate Howell, Senior Lecturer Food Chemistry, University of Melbourne; Nathan M D’Cunha, PhD Candidate, University of Canberra; Nenad Naumovski, Associate Professor in Food Science and Human Nutrition, University of Canberra, and Senaka Ranadheera, Lecturer, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

5 ways nutrition could help your immune system fight off the coronavirus



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Clare Collins, University of Newcastle

The coronavirus presents many uncertainties, and none of us can completely eliminate our risk of getting COVID-19. But one thing we can do is eat as healthily as possible.

If we do catch COVID-19, our immune system is responsible for fighting it. Research shows improving nutrition helps support optimal immune function.

Micronutrients essential to fight infection include vitamins A, B, C, D, and E, and the minerals iron, selenium, and zinc.

Here’s what we know about how these nutrients support our immune system and the foods we can eat to get them.




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1. Vitamin A

Vitamin A maintains the structure of the cells in the skin, respiratory tract and gut. This forms a barrier and is your body’s first line of defence. If fighting infection was like a football game, vitamin A would be your forward line.

We also need vitamin A to help make antibodies which neutralise the pathogens that cause infection. This is like assigning more of your team to target an opposition player who has the ball, to prevent them scoring.

Vitamin A is found in oily fish, egg yolks, cheese, tofu, nuts, seeds, whole grains and legumes.

Further, vegetables contain beta-carotene, which your body can convert into vitamin A. Beta-carotene is found in leafy green vegetables and yellow and orange vegetables like pumpkin and carrots.

2. B vitamins

B vitamins, particularly B6, B9 and B12, contribute to your body’s first response once it has recognised a pathogen.

They do this by influencing the production and activity of “natural killer” cells. Natural killer cells work by causing infected cells to “implode”, a process called apoptosis.

At a football match, this role would be like security guards intercepting wayward spectators trying to run onto the field and disrupt play.

Fish is a good source of vitamin B6.
Shutterstock

B6 is found in cereals, legumes, green leafy vegetables, fruit, nuts, fish, chicken and meat.

B9 (folate) is abundant in green leafy vegetables, legumes, nuts and seeds and is added to commercial bread-making flour.

B12 (cyanocobalamin) is found in animal products, including eggs, meat and dairy, and also in fortified soy milk (check the nutrition information panel).

3. Vitamins C and E

When your body is fighting an infection, it experiences what’s called oxidative stress. Oxidative stress leads to the production of free radicals which can pierce cell walls, causing the contents to leak into tissues and exacerbating inflammation.

Vitamin C and vitamin E help protect cells from oxidative stress.




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Vitamin C also helps clean up this cellular mess by producing specialised cells to mount an immune response, including neutrophils, lymphocytes and phagocytes.

So the role of vitamin C here is a bit like cleaning up the football ground after the game.

Good sources of vitamin C include oranges, lemons, limes, berries, kiwifruit, broccoli, tomatoes and capsicum.

Vitamin E is found in nuts, green leafy vegetables and vegetables oils.

4. Vitamin D

Some immune cells need vitamin D to help destroy pathogens that cause infection.

Although sun exposure allows the body to produce vitamin D, food sources including eggs, fish and some milks and margarine brands may be fortified with Vitamin D (meaning extra has been added).

Most people need just a few minutes outdoors most days.

People with vitamin D deficiency may need supplements. A review of 25 studies found vitamin D supplements can help protect against acute respiratory infections, particularly among people who are deficient.

5. Iron, zinc, selenium

We need iron, zinc and selenium for immune cell growth, among other functions.

Iron helps kill pathogens by increasing the number of free radicals that can destroy them. It also regulates enzyme reactions essential for immune cells to recognise and target pathogens.

Whole grain foods contain a variety of important nutrients.
Shutterstock

Zinc helps maintain the integrity of the skin and mucous membranes. Zinc and selenium also act as an antioxidant, helping mop up some of the damage caused by oxidative stress.

Iron is found in meat, chicken and fish. Vegetarian sources include legumes, whole grains and iron-fortified breakfast cereals.

Zinc is found in oysters and other seafood, meat, chicken, dried beans and nuts.

Nuts (especially Brazil nuts), meat, cereals and mushrooms are good food sources of selenium.




Read more:
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Putting it all together

It’s true some supermarkets are out of certain products at the moment. But as much as possible, focus on eating a variety of foods within each of the basic food groups to boost your intake of vitamins and minerals.

While vitamin and mineral supplements are not recommended for the general population, there are some exceptions.

Pregnant women, some people with chronic health conditions, and people with conditions that mean they can’t eat properly or are on very restrictive diets, may need specific supplements. Talk to your doctor, Accredited Practising Dietitian or pharmacist.




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And beyond diet, there are other measures you can take to stay as healthy as possible in the face of coronavirus.

Stop smoking to improve your lung’s ability to fight infection, perform moderate intensity exercise like brisk walking, get enough sleep, practise social distancing and wash your hands with soap regularly.The Conversation

Clare Collins, Professor in Nutrition and Dietetics, University of Newcastle

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Coles says these toys promote healthy eating. I say that’s rubbish



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Carla Liuzzo, Queensland University of Technology

As a parent, I find it so frustrating to take my children shopping, reusable bags in hand, only to be offered plastic toys at the checkout. It’s an incredibly confusing message to be sending kids. And it seems Coles is confused too.

Last year the company stated it wants to be “Australia’s most sustainable supermarket”. But with last week’s relaunch of “Stikeez” – yet another plastic collectables range off the back of their Little Shop promotion – Coles is showing dogged commitment to unsustainable marketing.

Stikeez are 24 plastic characters (plus four rare ones) in the shape of fruit and vegetables, aimed at encouraging kids to eat healthy food.




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After petitions against previous plastic “mini” campaigns by Coles and Woolworths, Coles will make the Stikeez characters returnable in store for recycling.

But this misses the point. Coles is generating waste needlessly in the first place. Surely it’s time to move beyond plastic freebies as a way of boosting sales?

Coles sent almost 100,000 tonnes of waste to landfill in 2019.
Shutterstock

Irresponsible marketing

We have a waste problem in this country. Australians are the third highest producers of waste per person, after the US and Canada. Some councils are having to stockpile plastic, there’s a federal plan to phase out exporting waste overseas and we have high rates of contamination of recyclables.

And Coles, one of Australia’s supermarket giants, sent almost 100,000 tonnes of waste to landfill in 2019. That’s 274 tonnes per day.




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But after their Little Shop collection provoked a consumer backlash, Coles took steps to reduce waste generated from their latest campaign. Stikeez wrapping contains partially recycled content, and Coles is providing in-store collection points where Stikeez can be returned and repurposed into shoe soles, in partnership with Save Our Soles.

Certainly this is preferable to throwing the items into the rubbish, but repurposing the plastic is not without environmental cost. Fuel is required to transport the waste and the process of repurposing plastic uses energy.

What’s more, asking shoppers to bring back their Stikeez puts the onus on consumers, rather than the company, to dispose of the items responsibly. And as we’ve seen by the low rates of recycling of soft plastics on a national level – recycling soft plastics is also offered in store – it’s far more convenient to throw items in the bin.

Coles haven’t publicised data about how many collectables they will produce.
Alpha/Flickr, CC BY-NC

Coles is also missing the point of the consumer backlash. When a company already generates huge quantities of waste in its core business and says it wants to be Australia’s most sustainable supermarket, it cannot generate additional waste on plastic marketing.

Boosting the bottom line

Last year Coles’ Little Shop put many parents offside. But Coles earned around A$200 million in extra revenue as a result of the original promotion.

Coles reported an increase in the first quarter of 2019 in sales of 5% and gained a competitive advantage over rival Woolworths, which managed only 1.5% in the same period. Obviously the bump in sales was too hard for Coles to resist.

It’s difficult to get an accurate figure on what waste this latest Stikeez campaign will generate. Coles haven’t publicised data about how many collectables they will produce. And waste contractors to Coles haven’t revealed how many collectables ended up in landfill last year, though there have been reports of Little Shop items ending up on beaches in Bali.

Last year, Coles said 94% of Little Shop collectables were either kept or given to family or friends. But University of Tasmania marketing expert Louise Grimmer discredited this data, saying it was not based on any meaningful longitudinal research that would allow such claims.

Stikeez undermines Coles’ sustainability efforts

If organisations produce plastic for marketing purposes, it’s difficult to see how we can achieve plastic recycling rates of 70% by 2025. This target – set by federal and state governments and which Coles has signed on to meet – also stipulates the removal of “problematic and unnecessary” single use plastic packaging.

Coles’ Little Shop promotion faced petitions from people concerned about the plastic waste it generated.
Shutterstock

Federal Assistant Minister for Waste, Trevor Evans, said finding a sustainable way to manage plastics was a major challenge and requires a coordinated effort. As a powerful household brand, Coles must unequivocally be part of this effort.




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Coles’ environmental policy says it’s “committed to doing business in an environmentally responsible manner”. But plastic freebies fly in the face of this policy.

Better waste regulation

Voluntary initiatives for companies to reduce packaging and plastic waste, which Coles have signed on to, have not produced meaningful results.

Currently only one-third of all plastic packaging in Australia is recycled.

Overseas countries have moved away from voluntary frameworks to more structured and enforceable regulations to reduce plastic production and waste. In fact, Europe voted to ban single use plastics last year.

As long as Australia lags on waste regulation, organisations such as Coles will continue to contravene their own environmental policies.


The Conversation contacted Coles for comment. Its response is as follows:

Customers have told us that they use Stikeez as a fun tool to encourage kids to eat more types of fresh foods. The collectibles form part of the Coles Fresh 5 Challenge which encourages kids to eat all the Five Food Groups daily. We made changes to the Stikeez campaign this year to ensure it’s more environmentally sustainable.

Stikeez collectibles, including those customers have from last year, can now be recycled at all Coles supermarkets. We have partnered with Australian recycling group Save our Soles so that Stikeez can be recycled through the same process that is used to recycle footwear in Australia since 2010 to create useful products like anti-fatigue mats, gym matting, retail flooring and carpet underlay.The Conversation

Carla Liuzzo, Sessional Lecturer, School of Business, Queensland University of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.

No food, no fuel, no phones: bushfires showed we’re only ever one step from system collapse



Australian Navy

Anthony Richardson, RMIT University

This summer’s bushfires were not just devastating events in themselves. More broadly, they highlighted the immense vulnerability of the systems which make our contemporary lives possible.

The fires cut road access, which meant towns ran out of fuel and fell low on food. Power to towns was cut and mobile phone services stopped working. So too did the ATMs and EFTPOS services the economy needs to keep running.

In a modern, wealthy nation such as Australia, how could this happen?

In answering this question, it’s helpful to adopt “systems thinking”. This approach views problems as part of an overall system, where each part relates to each other.

In other words, we need to look at the big picture.

Through a systems lens

Systems are everywhere, from the coral ecosystem of the Great Barrier Reef to the vast technology networks of global financial markets. In a human sense, social systems range from the small, such as a family, to large organisations or the national or global population.

The systems I mentioned just now are “complex” systems. This means they are connected to other systems in many ways. It also means a change in one part of the system, such as a bushfire in a landscape, can set off unpredicted changes in connected systems – be they political, technological, economic or social.




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All complex systems have three things in common:

  1. they need a constant supply of energy to maintain their functioning

  2. they are interconnected across a range of scales, from the personal and local to the global and beyond

  3. they are fragile when they have no “redundancy”, or Plan B.

Traders work on the floor of the New York Stock Exchange – part of the complex system of global financial markets.
Justin Lane/EPA

The case of East Gippsland

To better understand a complex system collapse, let’s examine what happened in Victoria’s East Gippsland region, particularly the coastal town of Mallacoota, during the recent fires.

This case demonstrates how one trigger (in this case, a bushfire) may start a cascade of events, but the intrinsic fragility of the system enables total collapse.

Transport-wise, neither East Gippsland nor Mallacoota itself are physically well connected. Fires cut both the only transport connection to East Gippsland, the Princes Highway, and the lone road out of Mallacoota.




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Smoke haze prevented air transport. This meant the only way out was by sea, in the form of intervention by the Australian Navy.

Second, there were no reserves of food, fuel, water, medical supplies or communications at hand when the fires had passed. Supplies ran so low there were reports of a looming “humanitarian crisis”.

These shortages are no surprise. In Australia, as in most developed countries, food and fuel distribution systems run on a “just in time” model. This approach, originally developed by Japanese car manufacturer Toyota, involves organising supply networks so materials are ordered and received when they are needed.

Such systems remove the need to store excess goods in warehouses, and are undoubtedly efficient. But they are also extremely fragile because there is no redundancy in the system – no Plan B.

Implications for Australia

Australia as a whole is, in many ways, just as fragile as Mallacoota.

We import 90% of our oil – a figure expected to rise to 100% by 2030. Much of that fuel passes through the Straits of Hormuz and then through the Indonesian archipelago. We have few alternative routes.




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Nor do we maintain sufficient back-up reserves of fuel. Australia is the only International Energy Agency (IEA) member that does not meet the obligation to keep 90 days of fuel supplies in reserve.

As East Gippsland and Mallacoota have shown, many other connected systems, such as food distribution networks, are critically dependent on this fragile fuel supply.

A close shave

On January 3 this year – the very day HMAS Choules evacuated people from Mallacoota – the US killed Iranian general Qasem Soleimani by drone strike.

If Iran had responded by disrupting the flow of oil through the Strait of Hormuz, throwing global oil supply into turmoil, Australia may have faced nationwide fuel shortages at the height of the bushfire crisis.

Late last year Australia reportedly had 18 days of petrol, 22 days of diesel and 23 days of jet fuel in reserve.

A global fuel crisis was avoided only due to restraint by both the US and Iran. Australia might not be so lucky next time.

Activists calling for de-escalation in the conflict between the US and Iran in January.
MARK R. CRISTINO/EPA

The need for reserves

Our communities, especially in bushfire-prone areas, need more redundancy to make them resilient to disasters. This might mean towns storing water, non-perishable food, blankets, medical supplies, a generator, a satellite phone and possibly fuel, in protected locations.

More broadly, Australia needs a national fuel reserve. This should be in line with the IEA’s 90-day obligations. In December last year, Australia reportedly had just 54 days’ worth of reserves.

The federal government has recently looked to bolster reserves through possible deals with the US and Holland. But overseas supplies will not be very helpful in an immediate crisis.

The implications of the bushfire crisis are clear. At a national and individual level, we must improve the resilience of the systems that make our daily life possible.The Conversation

Anthony Richardson, Tutor and Researcher, Centre for Urban Research, RMIT University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why it can be hard to stop eating even when you’re full: Some foods may be designed that way



Bet you can’t eat just one.
tlindsayg/Shutterstock

Tera Fazzino, University of Kansas and Kaitlyn Rohde, University of Kansas

All foods are not created equal. Most are palatable, or tasty to eat, which is helpful because we need to eat to survive. For example, a fresh apple is palatable to most people and provides vital nutrients and calories.

But certain foods, such as pizza, potato chips and chocolate chip cookies, are almost irresistible. They’re always in demand at parties, and they’re easy to keep eating, even when we are full.

In these foods, a synergy between key ingredients can create an artificially enhanced palatability experience that is greater than any key ingredient would produce alone. Researchers call this hyperpalatability. Eaters call it delicious.

Initial studies suggest that foods with two or more key ingredients linked to palatability – specifically, sugar, salt, fat or carbohydrates – can activate brain-reward neurocircuits similarly to drugs like cocaine or opioids. They may also be able to bypass mechanisms in our bodies that make us feel full and tell us to stop eating.

Our research focuses on rewarding foods, addictive behaviors and obesity. We recently published a study with nutritional scientist Debra Sullivan that identifies three clusters of key ingredients that can make foods hyperpalatable. Using those definitions, we estimated that nearly two-thirds of foods widely consumed in the U.S. fall into at least one of those three groups.

Documentaries like “Fed Up’ (2014) have linked obesity to food industry practices and American eating habits.

Cracking the codes

Foods that are highly rewarding, easily accessible and cheap are everywhere in our society. Unsurprisingly, eating them has been associated with obesity.

Documentaries in the last 15-20 years have reported that food companies have developed formulas to make palatable foods so enticing. However, manufacturers typically guard their recipes as trade secrets, so academic scientists can’t study them.

Instead, researchers have used descriptive definitions to capture what makes some foods hyperpalatable. For example, in his 2012 book ”Your Food Is Fooling You: How Your Brain Is Hijacked by Sugar, Fat, and Salt,“ David Kessler, former Commissioner of the U.S. Food and Drug Administration (FDA), wrote:

“What are these foods? …. Some are sweetened drinks, chips, cookies, candy, and other snack foods. Then, of course, there are fast food meals – fried chicken, pizza, burgers, and fries.”

But these definitions are not standardized, so it is hard to compare results across studies. And they fail to identify the relevant ingredients. Our study sought to establish a quantitative definition of hyperpalatable foods and then use it to determine how prevalent these foods are in the U.S.

In 2018, 31% of U.S. adults aged 18 and over were obese.
CDC

Three key clusters

We conducted our work in two parts. First we carried out a literature search to identify scientific articles that used descriptive definitions of the full range of palatable foods. We entered these foods into standardized nutrition software to obtain detailed data on the nutrients they contained.

Next we used a graphing procedure to determine whether certain foods appeared to cluster together. We then used the clusters to inform our numeric definition. We found that hyperpalatable foods fell into three distinct clusters:

– Fat and sodium, with more than 25% of total calories (abbreviated as kcal) from fat and at least 0.30% sodium per gram per serving. Bacon and pizza are examples.

– Fat and simple sugars, with more than 20% kcal from fat and more than 20% kcal from simple sugars. Cake is an example.

– Carbohydrates and sodium, with over 40% kcal from carbohydrates and at least 0.20% sodium per gram per serving. Buttered popcorn is an example.

Then we applied our definition to the U.S. Department of Agriculture’s Food and Nutrient Database for Dietary Studies, or FNDDS, which catalogs foods that Americans report eating in a biennial federal survey on nutrition and health. The database contained 7,757 food items that we used in our analysis.

Over 60% of these foods met our criteria for hyperpalatability. Among them, 70% were in the fat/sodium cluster, including many meats, meat-based dishes, omelets and cheese dips. Another 25% fell into the fat/simple sugars cluster, which included sweets and desserts, but also foods such as glazed carrots and other vegetables cooked with fat and sugar.

Finally, 16% were in the carbohydrate/sodium cluster, which consisted of carbohydrate-dense meal items like pizza, plus breads, cereals and snack foods. Fewer than 10% of foods fell into multiple clusters.

Many hyperpalatable foods are widely available and cheap.
gabriel12/Shutterstock

We also looked at which of the USDA’s food categories contained the most hyperpalatable foods. Over 70% of meats, eggs and grain-based foods in the FNDDS met our criteria for hyperpalatability. We were surprised to find that 49% of foods labeled as containing “reduced,” “low”, or zero levels of sugar, fat, salt and/or calories qualified as hyperpalatable.

Finally, we considered whether our definition captured what we hypothesized it would capture. It identified more than 85% of foods labeled as fast or fried, as well as sweets and desserts. Conversely, it did not capture foods that we hypothesized were not hyperpalatable, such as raw fruits, meats or fish, or 97% of raw vegetables.

Tackling obesity

If scientific evidence supporting our proposed definition of hyperpalatable foods accumulates, and it shows that our definition is associated with overeating and obesity-related outcomes, our findings could be used in several ways.

First, the FDA could require hyperpalatable foods to be labeled – an approach that would alert consumers to what they may be eating while preserving consumer choice. The agency also could regulate or limit specific combinations of ingredients, as a way to reduce the chance of people finding foods that contain them difficult to stop eating.

Consumers also could consider the role of hyperpalatable foods in their own lives. Our team needs to do further work validating our definition before we translate it for the public, but as a first step, individuals can examine whether the foods they eat contain multiple ingredients such as fat and sodium, particularly at high levels. Recent surveys show increased interest among U.S. consumers in making informed food choices, although they often aren’t sure which sources to trust.

One starting point for people concerned about healthy eating is to consume foods that are unlikely to be hyperpalatable – items that occur naturally and have few or no additional ingredients, such as fresh fruit. As food writer Michael Pollan recommends, “Don’t eat anything your great-grandmother wouldn’t recognize as food.”

[ Get the best of The Conversation, every weekend. Sign up for our weekly newsletter. ]The Conversation

Tera Fazzino, Assistant Professor of Psychology; Associate Director of the Cofrin Logan Center for Addiction Research and Treatment, University of Kansas and Kaitlyn Rohde, Research Assistant, Cofrin Logan Center for Addiction Research and Treatment., University of Kansas

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Should you avoid meat for good health? How to slice off the facts from the fiction



Meat is a very popular food for most Americans. Its nutritional value is a topic of much debate.
puhhha/Shutterstock.com

Dariush Mozaffarian, Tufts University

More than half of Americans who make New Year’s resolutions resolve to “eat healthier.” If you’re one, you might be confused about the role meat should play in your health.

It’s no wonder you’re confused. One group of scientists says that reducing red and processed meat is a top priority for your health and the planet’s. Another says these foods pose no problems for health. Some of your friends may say it depends, and that grass-fed beef and “nitrite-free” processed meats are fine. At the same time, plant-based meat alternatives are surging in popularity, but with uncertain health effects.

As a cardiologist and professor of nutrition, I’d like to clear up some of the confusion with five myths and five facts about meat.

First, the myths.

Red meat, while very popular, has not been shown to have health benefits.
Natalia Lisovskaya/Shutterstock.com

Myth: Red meat is good for health

Long-term observational studies of heart disease, cancers or death and controlled trials of risk factors like blood cholesterol, glucose and inflammation suggest that modest intake of unprocessed red meat is relatively neutral for health. But, no major studies suggest that eating it provides benefits.

So, while an occasional serving of steak, lamb or pork may not worsen your health, it also won’t improve it. And, too much heme iron, which gives red meat its color, may explain why red meat increases risk of Type 2 diabetes. Eating red meat often, and eating processed meat even occasionally, is also strongly linked to colorectal cancer.

Myth: You should prioritize lean meats

For decades, dietary guidance has focused on lean meats because of their lower fat, saturated fat and cholesterol contents. But these nutrients don’t have strong associations with heart attacks, cancers or other major health outcomes.

Other factors appear more important. Processed meats, such as bacon, sausage, salami and cold cuts, contain high levels of preservatives. Sodium, for example, raises blood pressure and stroke risk, while the body converts nitrites to cancer-causing nitrosamines. Lean or not, these products aren’t healthy.

Myth: Focus on a ‘plant-based’ diet

“Plant-based” has quickly, but somewhat misleadingly, become a shorthand for “healthy.” First, not all animal-based foods are bad. Poultry and eggs appear relatively neutral. Dairy may have metabolic benefits, especially for reducing body fat and Type 2 diabetes. And, seafood is linked to several health benefits.

Conversely, many of the worst foods are plant-based. Consider white rice, white bread, fries, refined breakfast cereals, cookies and so on. These foods are high in refined starch and sugar, representing 42% of all calories in the U.S., compared to about 5% of U.S. calories from unprocessed red meats, and 3% from processed meats.

Either a “plant-based” or omnivore diet is not healthy by default. It depends on what you choose to eat.

Myth: Grass-fed beef is better for your health

Conventional livestock eat a combination of forage (grass, other greens, legumes) plus hay with added corn, soy, barley or grain. “Grass-fed,” or “pasture-raised,” livestock eat primarily, but not exclusively, forage. “Grass-finished” livestock should, in theory, only eat forage. But no agency regulates industry’s use of these terms. And “free range” describes where an animal lives, not what it eats.

“Grass-fed” may sound better, but no studies have compared health effects of eating grass-fed versus conventional beef. Nutrient analyses show very modest differences between grass-fed and conventionally raised livestock. You might eat grass-fed beef for personal, environmental or philosophical reasons. But don’t expect health benefits.

Myth: Plant-based meat alternatives are healthier

Products like Impossible Burger and Beyond Meat are clearly better for the environment than conventionally raised beef, but their health effects remain uncertain. Most nutrients in plant-based alternatives are, by design, similar to meat. Using genetically engineered yeast, Impossible even adds heme iron. These products also pack a lot of salt. And, like many other ultra-processed foods, they may lead to higher calorie intake and weight gain.

So, what are the facts?

Sausages wrapped in bacon are a double whammy of unhealthy meat, as both bacon and sausage are processed meats.
MShev/Shutterstock.com

Fact: Processed meats are bad for health

Processed meats contain problematic preservatives. Even those labeled “no nitrates or nitrites added” contain nitrite-rich fermented celery powder. A current petition by the Center for Science in the Public Interest asks the FDA to ban the misleading labeling.

Besides the sodium, nitrites and heme, processed meats can contain other carcinogens, produced by charring, smoking or high-temperature frying or grilling. These compounds may not only harm the person who eats these products; they can also cross the placenta and harm a fetus.

Fact: A meatless diet is not, by itself, a healthy diet

Most diet-related diseases are caused by too few health-promoting foods like fruits, nuts, seeds, beans, vegetables, whole grains, plant oils, seafood and yogurt. Additional health problems come from too much soda and ultra-processed foods high in salt, refined starch or added sugar. Compared to these major factors, avoiding or occasionally eating unprocessed red meat, by itself, has modest health implications.

Fact: Beef production is devastating the environment

In terms of land use, water use, water pollution and greenhouse gases, unprocessed red meat production causes about five times the environmental impact of fish, dairy or poultry. This impact is about 20 times higher than that of eggs, nuts or legumes, and 45 to 75 times higher than the impact of fruits, vegetables or whole grains. A 2013 UN report concluded that livestock production creates about 15% of all global greenhouse gas emissions, with nearly half coming from beef alone.

Fact: Plant-based meats are better for the environment

Production of plant-based meat alternatives, compared to conventional beef, uses half the energy, one-tenth of the land and water, and produces 90% less greenhouse gas. But, no studies have yet compared plant-based meat alternatives to more natural, less processed options, such as mushrooms or tofu.

Fact: Many questions remain

Which preservatives or other toxins in processed meat cause the most harm? Can we eliminate them? In unprocessed red meats, what exactly increases risk of Type 2 diabetes? What innovations, like feeding cows special strains of seaweed or using regenerative grazing, can reduce the large environmental impacts of meat, even grass-fed beef? What are the health implications of grass-fed beef and plant-based meat alternatives?

Like much in science, the truth about meat is nuanced. Current evidence suggests that people shouldn’t eat unprocessed red meat more than once or twice a week. Grass-fed beef may be modestly better for the environment than traditional production, but environmental harms are still large. Data don’t support major health differences between grass fed and conventional beef.

Similarly, plant-based meat alternatives are better for the planet but not necessarily for our health. Fruits, nuts, beans, vegetables, plant oils and whole grains are still the best bet for both human and planetary health.

[ You’re smart and curious about the world. So are The Conversation’s authors and editors. You can read us daily by subscribing to our newsletter. ]The Conversation

Dariush Mozaffarian, Dean of Nutrition Science and Policy, Tufts University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Hoping to get in shape for summer? Ditch the fads in favour of a diet more likely to stick



The benefits of a juice cleanse or detox aren’t likely to be sustained over time.
Fron shutterstock.com

Yasmine Probst, University of Wollongong and Vivienne Guan, University of Wollongong

Weight gain can creep up on us. Over the winter months we enjoy foods that create a feeling of comfort and warmth. Many of these foods tend to be higher in calories, usually from fat or added sugars.

As we enter the summer months, some of us start to think about getting in shape – and how we’re going to look in a bathing costume.

These concerns might be met with the temptation to seek a “quick fix” to weight loss. But this sort of approach is likely to mean finding yourself back in the same position this time next year.

Looking past the quick fix and fad diets to longer-term solutions will improve your chance of keeping the weight off and staying healthy all year round.




Read more:
Health Check: why do we crave comfort food in winter?


Losing weight shouldn’t be a short-term solution

Extra body fat is a risk factor for developing chronic diseases including type 2 diabetes and heart disease. With two in three Australians carrying too much body fat, many of us may be well-intentioned, but not making the best choices when it comes to what we eat.

Weight loss is largely a balance of choosing the right foods and being physically active in order to tip our internal energy balance scales in the right direction.

For the most part, quick-fix diets are based on calorie restriction as a means of weight loss. They focus on different strategies to get you to eat fewer calories without having to actively think about it.

Fad diets tend to share similar characteristics, such as eating fewer varieties of foods, fasting, and replacing meals.




Read more:
Five food mistakes to avoid if you’re trying to lose weight


But weight loss isn’t just about swapping one or two foods for a month or two; it’s about establishing patterns to teach our bodies new habits that can be maintained into the future.

Fad diets and quick fix options can be limited in several respects. For example, they can be difficult to stick to, or people on them can regain weight quickly after stopping the diet. In some cases, there is insufficient research around their health effects in the longer term.

Exercise is also an important part of losing weight.
From shutterstock.com

Let’s take a look at the way some of these characteristics feature in three popular diets.

Juicing/detoxification

Juicing or detoxification diets usually last two to 21 days and require a person to attempt a juice-focused form of fasting, often in combination with vitamin or mineral supplements in place of all meals.

People on this diet lose weight rapidly because of the extremely low calorie intake. But this is a severely restricted type of diet and particularly difficult to follow long term without a risk of nutrient deficiency.

Also, while it might hold appeal as a marketing buzzword, detoxification is not a process the body needs to go though. Our livers are efficient at detoxifying with very little help.




Read more:
Trust Me, I’m An Expert: what science says about how to lose weight and whether you really need to


Intermittent fasting

An intermittent fasting diet involves a combination of fasting days and usual eating days. The fasting strategies include complete fasting (no food or drinks are consumed on fasting days) and modified fasting (20-25% of calories is consumed on fasting days).

This diet leads to weight loss due to an overall decrease in calorie intake. But it’s hard to stick with the fasting pattern as it results in intense hunger. Similarly, this diet can lead to binge eating on usual eating days.

But even though people are allowed to eat what they want on non-fasting days, research shows most do not over-eat.




Read more:
Blood type, Pioppi, gluten-free and Mediterranean – which popular diets are fads?


Overall, for people who are able to stick with intermittent fasting, we don’t have enough evidence on the benefits and harms of the diet over time.

Long term energy restriction without fasting may result in the same weight outcomes and may be a better approach to continued weight management.

The paleo diet

The palaeolithic (paleo) diet was designed to reflect the foods consumed by our Stone Age ancestors before the agricultural revolution.

The paleo diet excludes processed foods and sugars. This recommendation lines up with the current evidence-based dietary recommendations. However, the paleo diet also excludes two major food groups – grain and dairy foods.

Developing new healthier habits can take time and perseverance, but will pay off.
From shutterstock.com

While short-term weight loss might be achieved, there’s no conclusive proof of benefit for weight loss and nutritional balance in the long term. People who follow the paleo diet might be at risk of nutritional deficiencies if they’re not getting any grains or dairy.

So it’s worth taking cues from the paleo diet in terms of limiting processed foods and sugars. But if you’re thinking of adopting the diet in its entirety, it would be important to seek support from a health professional to ensure you’re not missing out on essential nutrients.

Things to look out for

So how can you tell if a diet is likely to lead to long term weight loss success? Here are some questions to ask:

  1. does it incorporate foods from across the five food groups?

  2. is it flexible and practical?

  3. can the foods be easily bought at the supermarket?

If the answer to these three questions is “yes”, you’re likely on to a good one. But if you’re getting at least one “no”, you might want to think carefully about whether the diet is the right choice for sustained weight loss.




Read more:
Four simple food choices that help you lose weight and stay healthy


Of course, seeing results from a diet also depends on your level of commitment. While it may be easier to stay committed in the shorter term, if you want to keep the weight off year round, it’s important to make checking in with your food choices part of your ongoing routine.The Conversation

Yasmine Probst, Associate professor, University of Wollongong and Vivienne Guan, Associate Research Fellow, School of Medicine, University of Wollongong

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Cap your alcohol at 10 drinks a week: new draft guidelines



Further evidence about the harms of alcohol has accumulated over the past decade since the last guidelines were released.
Syda Productions/Shtterstock

Nicole Lee, Curtin University

New draft alcohol guidelines, released today, recommend healthy Australian women and men drink no more than ten standard drinks a week and no more than four on any one day to reduce their risk of health problems.

This is a change from the previous guidelines, released in 2009, that recommended no more than two standard drinks a day (equating to up to 14 a week).

(If you’re unsure what a standard drink looks like, use this handy reference.)

The guidelines also note that for some people – including teens and women who are pregnant or breastfeeding – not drinking is the safest option.




Read more:
Drink, drank, drunk: what happens when we drink alcohol in four short videos


What are the new recommendations based on?

The National Health and Medical Research Council looked at the latest research and did some mathematical modelling to come to these recommendations.

It found the risk of dying from an alcohol-related disease or injury is about one in 100 if you drink no more than ten standard drinks a week and no more than four on any one day.

So, for every 100 people who stay under these limits, one will die from an alcohol-related disease or injury.

This is considered an “acceptable risk”, given drinking alcohol is common and it’s unlikely people will stop drinking altogether. The draft guidelines take into account that, on average, Australian adults have a drink three times a week.

Why did the guidelines need updating?

Recent research has shown there is a clear link between drinking alcohol and a number of health conditions. These include at least seven cancers (liver, oral cavity, pharyngeal, laryngeal, oesophageal, colorectal, liver and breast cancer in women); diabetes; liver disease; brain impairment; mental health problems; and being overweight or obese.

Some previous research suggested low levels of alcohol might be good for you, but we now know these studies were flawed. Better quality studies have found alcohol does not offer health benefits.




Read more:
Health check: is moderate drinking good for me?


The new guidelines are easier to follow than the previous guidelines, which gave recommendations to reduce both short-term harms and longer-term health problems. But some people found these confusing.

Although most Australians drink within the previously recommended limits, one study found one in five adults drank more than the guidelines suggested and almost half could not correctly identify recommended limits.

The draft new guidelines are easier to follow than the old ones.
sama_ja/Shutterstock

Although women tend to be more affected by alcohol than men, at the rates of consumption recommended in the guidelines, there is little difference in long term health effects so the guidelines apply to both men and women.

The recommended limits are aimed at healthy men and women, because some people are at higher risks of problems at lower levels of consumption. These include older people, young people, those with a family history of alcohol problems, people who use other drugs at the same time (including illicit drugs and prescribed medication), and those with physical or mental health problems.

The guidelines are currently in draft form, with a public consultation running until February 24.

After that, there will be an expert review of the guidelines and the final guidelines will be released later in 2020. There may be changes to the way the information is presented but the recommended limits are unlikely to change substantially, given they’re based on very careful and detailed analysis of the evidence.

What’s the risk for people under 18?

The draft guidelines recommend children and young people under 18 years drink no alcohol, to reduce the risk of injury and other health harms.

The good news is most teenagers don’t drink alcohol. Among 12 to 17 year olds, only 20% have had a drink in the past year and 1.4% drink weekly. The number of teenagers who have never had a drink has increased significantly in the last decade, and young people are having their first drink later.




Read more:
Three ways to help your teenage kids develop a healthier relationship with alcohol


However, we know teenagers are more affected by alcohol than adults. This includes effects on their developing brain. We also know the earlier someone starts drinking, the more likely they will experience problems, including dependence.

The idea that if you give teenagers small sips of alcohol it will reduce risk of problems later has now been debunked. Teens that have been given even small amounts of alcohol early are more likely to have problems later.

What’s the risk for pregnant and breastfeeding women?

The guidelines recommend women who are pregnant, thinking about becoming pregnant or breastfeeding not drink any alcohol, for the safety of their baby.




Read more:
Health Check: what are the risks of drinking before you know you’re pregnant?


We now have a much clearer understanding of the impacts of alcohol on the developing foetus. Foetal alcohol spectrum disorder (FASD) is a direct result of foetal exposure to alcohol in the womb. Around one in 67 women who drink while pregnant will deliver a baby with foetal alcohol spectrum disorder.

Foetal alcohol spectrum disorder is characterised by a range of physical, mental, behavioural, and learning disabilities ranging from mild to severe – and is incurable.

Worried about your own or someone else’s drinking?

If you enjoy a drink, stick within these recommended maximums to limit the health risks of alcohol.

If you have trouble sticking to these limits, or you are worried about your own or someone else’s drinking, call the National Alcohol and other Drug Hotline on 1800 250 015 to talk through options or check out these resources online.




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The Conversation


Nicole Lee, Professor at the National Drug Research Institute (Melbourne), Curtin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Tough nuts: why peanuts trigger such powerful allergic reactions



The humble peanut. Tasty for most, treacherous for some.
Dr Dwan Price, Author provided

Dwan Price, Deakin University

Food allergens are the scourge of the modern school lunchbox. Many foods contain proteins that can set off an oversized immune reaction and one of the fiercest is the humble peanut.

Around 3% of children in Australia have a peanut allergy, and only 1 in 5 of them can expect to outgrow it. For these unlucky people, even trace amounts of peanut can trigger a fatal allergic reaction.

But what sets the peanut apart from other nuts? Why is it so good at being an allergen?

To answer this, we have to explore the pathway from allergen to allergy, and just what it is about an allergen that triggers a response from the immune system.




Read more:
What are allergies and why are we getting more of them?


How food gets to the immune system

Before coming into contact with the immune system, an allergen in food needs to overcome a series of obstacles. First it needs to pass through the food manufacturing process, and then survive the chemicals and enzymes of the human gut, as well as cross the physical barrier of the intestinal lining.

After achieving all of this, the allergen must still have the identifying features that trigger the immune system to respond.

Many food allergens successfully achieve this, some better than others. This helps us to understand why some food allergies are worse than others.

The most potent allergens – like peanuts – have many characteristics that successfully allow them to overcome these challenges, while other nuts display these traits to a lesser extent.

Strength in numbers

The first characteristic many allergenic foods have, especially peanuts, is strength in numbers. Both tree nuts and peanuts contain multiple different allergens. At last count, cashews contain three allergens, almonds have five, walnuts and hazelnuts have 11 each and peanuts are loaded with no less than 17.

Each allergen has a unique shape, so the immune system recognises each one differently. The more allergens contained in a single food, the higher the potency.
Additionally, many of these allergens also have numerous binding sites for both antibodies and specialised immune cells, further increasing their potency.

Stronger through scorching

The first hurdle for a food allergen is the food manufacturing process. Many nuts are roasted prior to consumption. For most foods, heating changes the structure of proteins in a way that destroys the parts that trigger an immune response. This makes them far less potent as allergens.

This is not the case for many tree nuts: allergens in almonds, cashews and hazelnuts survived roasting with no loss of potency.

And for the major peanut allergens, it’s even worse. Roasting actually makes them more potent.




Read more:
Can I prevent food allergies in my kids?


The gauntlet of the gut

From here, the allergen will have to survive destruction by both stomach acid and digestive enzymes within the human gut. Many nut allergens have the ability to evade digestion to some degree.

Some simply have a robust structure, but peanut allergens actively inhibit some of the digestive enzymes of the gut. This helps them safely reach the small intestine, where the allergens then need to cross the gut lining to have contact with the immune system.

This is where peanut allergens really stand apart from most other allergens. They have the ability to cross the intestinal cells that make up the gut lining. Given their relative sizes, this is like a bus squeezing itself through a cat flap.

Peanut allergens accomplish this remarkable feat by altering the bonds that hold the gut cells together. They can also cross the lining by hijacking the gut’s own ability to move substances. Once across, the allergens will gain access to the immune system, and from there an allergic response is triggered.

Peanut allergens attack the bonds that hold intestinal cells together.
Dr Dwan Price, Author provided

The combination of multiple allergens, numerous immune binding sites, heat stability, digestion stability, enzyme blocking, and the effect on the gut lining makes peanut a truly nasty nut.

Where to from here?

This leaves us with a nagging question: if peanuts are so potent, why doesn’t everyone develop a peanut allergy? We still don’t know.

Recently, a potential vaccine developed by researchers from the University of South Australia has shown promise in reprogramming the immune system of mice and blood taken from people with peanut allergy. Will this translate to a potential treatment for peanut allergy? We will have to wait and see.

For now, the more we learn about the action of allergens, and the more we understand their effects on our body, the more we can develop new ways to stop them. And eventually, we might outsmart these clever nuts for good.The Conversation

Dwan Price, Molecular Biologist and Postdoc @ Deakin AIRwatch pollen monitoring system., Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.