Why the Australasian Health Star Rating needs major changes to make it work



Most consumers are unaware that the Health Star Rating system is compensatory, and that one negative nutritional attribute, such as high sugar, can be cancelled out by a positive attribute like fibre.
from http://www.shutterstock.com, CC BY-ND

Jessica C Lai, Victoria University of Wellington; Alana Harrison, Victoria University of Wellington; Hongzhi Gao, Victoria University of Wellington, and Samuel Becher, Victoria University of Wellington

Unhealthy diets cause multiple physical and mental health problems. To help consumers make healthier choices, Australia and New Zealand introduced the voluntary Health Star Rating (HSR) system in 2014.

The system is supposedly designed to provide consumers with an overall signal about a food’s healthiness. Presumably, this should nudge consumers to make more informed and healthier decisions.

Five years on, the Australian and New Zealand governments are conducting a system review. Our research shows that, while the initiative is noble, the devil is in the details. There is a need, and hopefully an opportunity, to improve the system and reconsider some of its key aspects.




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Loopholes and consumer misconception

Under the HSR system, products are labelled from 0.5 stars (the least healthy score) to 5 stars (the healthiest products). The rating is determined by evaluating the overall nutritional value of the product. It compares the content of “good” ingredients (i.e. fibre, protein, fruit, vegetables, nuts and legumes) with the “bad” ones (i.e. saturated fat, energy, total sugar and sodium).

But we believe most consumers are unaware that the HSR system is compensatory. This means one negative nutritional attribute can be cancelled out, or balanced, by a positive attribute. A manufacturer can receive a high HSR score for a product rich in sugar by adding a healthy ingredient such as fibre.


CC BY-ND

It is also likely that most consumers are unaware that the HSR rating is calculated on an “as prepared” basis. This means a product can enjoy a high rating based on the nutritional value of preparatory ingredients.

Milo found itself embroiled in controversy for displaying 4.5 stars on its chocolate powder, though the powder itself clearly does not merit this rating. The 4.5-star rating was based on consuming merely three teaspoons of powder combined with skim milk. But who actually consumes Milo this way?

Furthermore, HSR scores are intended to allow comparison only among similar products. A four-star rating for a cereal cannot be compared to a four-star rating given to milk. While the two products display the same number of stars, their healthiness may differ significantly.




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What holds the system back

There is scepticism about the HSR’s authenticity, reliability and effectiveness. This stems in part from the system being self-regulated.

In addition, the system is non-mandatory, leaving manufacturers free to decide when and how to use it. For instance, only around 20% of packaged goods available in New Zealand and Australian supermarkets have an HSR. To add to the distortion, a disproportionate number of these show high ratings. This indicates that manufacturers only use the HSR for their healthier products.

A voluntary system does little to counter the inbuilt incentive that manufacturers have to use unhealthy components such as sugar, salt and saturated fats. These produce pleasure and create “craveable” foods and food addiction. Manufacturers likely do not use a HSR for these products. However, consumers do not interpret missing information as “the worst-case scenario”, but assume average quality.

Finally, the system does not effectively assist the vulnerable consumers who need it the most. While HSR does help some middle- to high-income consumers, it does a poor job with respect to consumers of low socio-economic status. This suggests that the label requires consumers to be educated about its meaning.

Time to move forward

Some improvements could carry the HSR forward a great distance.

If the system were made mandatory, it would likely raise consumers’ awareness. There should also be more education initiatives about the HSR. This, in turn, would incentivise manufacturers to produce healthier foods and beverages.

At the same time, we should strive to minimise the costs involved and consider backing the system with government funding. This would allow all businesses to participate in the program, including less profitable or smaller businesses. It would also prevent costs from being passed onto consumers.

As a minimum, if the system is not made mandatory, a general “non-participation” label should be introduced. If a producer opts not to label its product, it should be required to use a conspicuous cautionary statement. Such a statement should declare, for instance, that “the manufacturer has chosen not to verify the health rating of this product” or “the healthiness of this product cannot be verified”.

Studies show the HSR rating would have a bigger impact if placed in the upper left corner of the packaging and used colours. It could use a traffic light system, with 0.5-2.5 stars on a red background, 3 to 4 stars on amber and 4.5-5 star products on green. The colour-coded system has proved to be more effective with marginalised groups of consumers.

All easier said than done.

Healthy diets are important for physical and psychological well-being and for strengthening our communities and economies. However, any regulation of the food industry is likely to be resisted by its strong and well-organised lobbying power. To fight this battle, the consumers’ voice is crucial to ensure we can all make good and healthy foods choices.The Conversation

Jessica C Lai, Senior Lecturer in Commercial Law, Victoria University of Wellington; Alana Harrison, LLB(Hons) & BCOM Undergraduate Student, Victoria University of Wellington; Hongzhi Gao, Associate professor, Victoria University of Wellington, and Samuel Becher, Associate Professor of Business Law, Victoria University of Wellington

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

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Research Check: is white meat as bad for your cholesterol levels as red meat?



Whether you’re eating red meat or white meat, a lean cut is the healthier way to go.
From shutterstock.com

Clare Collins, University of Newcastle

You’ve probably heard eating too much fatty red meat is bad for your health, while lean meat and chicken are better choices. So, recent headlines claiming white meat is just as bad for your cholesterol levels as red meat might have surprised you.

The reports were triggered by a paper published in the The American Journal of Clinical Nutrition earlier this month.

The study did find lean white meat had the same effect on cholesterol levels as lean red meat. While this might be construed as good news by lovers of red meat, more research on this topic is needed for a clearer picture.

How was this study conducted?

The researchers set out to compare three diets: one where the main dietary source of protein came from eating red meat (beef and pork), another where it came from poultry (chicken and turkey), and a third where it came from plant foods (legumes, nuts, grains and soy products).

They wanted to measure the impact of these diets on specific categories of blood fats, as markers of heart disease risk. They tested blood fat markers including low density lipoprotein cholesterol (or LDL, commonly known as “bad cholesterol”), apolipoprotein B (apoB), and the ratio of total cholesterol to high density lipoprotein cholesterol (or HDL, commonly known as “good cholesterol”).




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How to get the nutrients you need without eating as much red meat


The researchers also wanted to know whether blood fat levels changed more when the background dietary patterns were high in saturated fat, derived mostly from full-fat dairy products and butter, or when they were low in saturated fat.

To achieve this, 177 adults with blood cholesterol levels in the normal range were randomised to follow either a high-saturated fat diet (14% of total energy intake) or a low-saturated fat diet (7% of total energy intake).

Within these two groups they were further randomly assigned to follow three separate diets for four weeks each: red meat, white meat, and plant protein sources. The main protein sources in the meat groups came from lean cuts of red and white meat. In the plant diet, protein came from legumes, nuts, grains and soy products.

Participants met research staff weekly to collect their food products and received counselling on following their specified diet. Participants were asked to maintain their physical activity level and keep their weight as stable as possible so these factors did not bias the results.

To eliminate any carry-over effects from eating one type of protein to the next, participants were given between two and seven weeks break in between each diet and told to return to their usual eating patterns.




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What did the study find?

Some participants dropped out along the way, so in the end researchers had results from 113 participants.

Blood concentrations of LDL cholesterol and apoB were lower following the plant protein diet period, compared to both the red and white meat periods. This was independent of whether participants were on a background diet of high- or low-saturated fat.

There was no statistically significant difference in the blood fat levels of those eating red meat compared to those eating white meat.

We’re often told to limit our consumption of red meat.
From shutterstock.com

Eating a diet high in saturated fat led to significant increases in blood levels of LDL cholesterol, apoB, and large LDL particles compared with a background diet low in saturated fat.

So, all the dietary protein sources as well as the level of saturated fat intake had significant effects on total cholesterol, LDL cholesterol, non-HDL cholesterol, and apoB levels.

How should we interpret the results?

Although the test diets only lasted four weeks each, this study is important. It’s rare to see intervention studies that directly compare eating different types of meat and sources of protein and the impact on heart-disease risk factors. This is partly due to the challenge and expense of providing the food and getting people to follow specific diets.

Most studies to date have been cohort studies where people are categorised based on what they eat, then followed up for many years to see what happens to their health.

One review of cohort studies found no greater risk of stroke in those who eat more poultry compared to less poultry, while another showed a higher risk of stroke among those eating more red and processed meat relative to poultry intake.




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There are a few things to keep in mind with this study. First, the researchers used the leanest cuts of both red and white meats, and removed all visible fat and skin. If participants were eating fatty meat, we may have seen different results.

The significant variation in breaks between different diets (ranging from two to seven weeks) may have also affected the results. Participants with a longer break would have had more time for their blood cholesterol levels to change, compared to those with shorter breaks.

Finally, in reporting their results, it would have been better to include all 177 participants who began the study. People who drop out often have different health characteristics and leaving them out may have biased results.

This short-term study does not provide evidence that choosing lean white meat over red meat is either better or worse for your health.

But the findings are consistent with recommendations from the Heart Foundation to include a variety of plant-based foods in our diets, foods containing healthy types of fat and lower amounts of saturated fat, and in particular, to choose lean red meat and poultry. – Clare Collins


Blind peer review

The article presents a fair, balanced and accurate assessment of the study. In this study, they showed lean red meat and lean white meat (with all visible fat and skin removed) had the same effect on blood fat levels.

Importantly, plant protein sources (such as legumes, nuts, grains and soy products) lowered blood fat levels compared to the red and white meats, and this was independent of whether the participants had been placed on a background diet low or high in saturated fats. This study did not look at the impact of a fish-based diet on blood fats. – Evangeline Mantzioris




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Research Checks interrogate newly published studies and how they’re reported in the media. The analysis is undertaken by one or more academics not involved with the study, and reviewed by another, to make sure it’s accurate.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.

How to get the nutrients you need without eating as much red meat



The average Australian eats 81 grams of red meat a day, while the planetary diet recommends just 14g.
Napocska/Shutterstock

Evangeline Mantzioris, University of South Australia

If you’re a red meat-eater, there’s a good chance you’re eating more of it than you should. At last count, Australians ate an average of 81 grams of red meat per day.

The planetary health diet was developed by researchers to meet the nutritional needs of people around the world, while reducing food production’s environmental impact. It recommends reducing our red meat intake to around 14g a day. That’s around 100g of red meat a week.




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Australia’s dietary guidelines are more conservative and recommend limiting red meat intake to a maximum of 455g a week, or 65g a day, to reduce the additional cancer risk that comes from eating large quantities of red meat.

So, what should you eat instead? And how can you ensure you’re getting enough protein, iron, zinc and vitamin B12?

Protein

Animal sources of protein provide essential amino acids, which the body uses to make muscle, tissue, hormones, neurotransmitters and the different cells and antibodies in our immune system.

The planetary health diet offers a good blueprint for gaining enough protein from a variety of other animal sources. It recommends eating, on average:

  • 25g of chicken per day
  • 28g of fish per day day
  • 1.5 eggs per week
  • 200g of milk per day day
  • 50g of cheese per day.

In addition to the 14g of red meat in the planetary health diet, these foods would provide a total of 45g of protein per day, which is around 80% of our daily protein needs from animal sources.

The remaining protein required (11g) is easily met with plant foods, including nuts, legumes, beans and wholegrains.

Nuts are a good alternative to meat.
Eakrat/Shutterstock

Iron

Iron is essential for many of the body’s functions, including transporting oxygen to the blood.

Iron deficiency can lead to anaemia, a condition in which you feel tired and lethargic.




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Pre-menopausal women need around 18 milligrams a day, while men only need 8mg. Pre-menopausal women need more iron because of the blood they lose during menstruation.

So, how can you get enough iron?

Beef, of course, is a rich source of iron, containing 3.3mg for every 100g.

The same amount of chicken breast contains 0.4mg, while the chicken thigh (the darker meat) contains slightly higher levels, at 0.9mg.

Pork is similarly low in iron at 0.7mg.

But kangaroo will provide you with 4.1mg of iron for every 100g. Yes, kangaroo is a red meat but it produces lower methane emissions and has one-third the levels of saturated fat than beef, making it a healthier and more environmentally friendly alternative.

Plant protein sources are also high in iron: cooked kidney beans have 1.7mg and brown lentils have 2.37mg per 100g.

Kidney beans and lentils are good sources of iron.
Hermes Rivera

If you wanted to cut your red meat intake from the 81g average to the recommended 14g per day while still getting the same amount of iron, you would need to consume the equivalent of either 50g of kangaroo, 100g of brown lentils or 150g of red kidney beans per day.

Zinc

Zinc is an essential mineral that helps the body function optimally. It affects everything from our ability to fight bugs, to our sense of smell and taste.

Zinc requirements are higher for men (14mg a day) than women (8mg a day) due to zinc’s role in the production and development of sperm.

Of all meat sources, beef provides the most zinc, at 8.2mg per 100g.

Chicken breast provides just 0.68mg, while the chicken thigh has 2mg.

In kangaroo meat, the levels of zinc are lower than beef, at 3.05mg.

The richest source of zinc is oysters (48.3mg).

Beans such lentils, red kidney beans and chickpeas all provide about 1.0mg per 100g.

To meet the shortfall of zinc from reducing your red meat intake, you could eat 12 oysters a day, which is unlikely. Or you could eat a combination of foods such as 150g of red kidney beans, one serve (30g) of zinc-supplemented cereals like Weet-bix, three slices of wholegrain bread, and a handful of mixed nuts (30g).

Vitamin B12

Vitamin B12 is important for healthy blood and nerve function. It’s the nutrient of most concern for people cutting out meat products as it’s only found in animal sources.

Requirements of vitamin B12 are the same for both women and men at 2.4 micrograms (mcg) a day.

Beef and kangaroo provide 2.5mcg per 100g serve, while chicken and turkey provide about 0.6mcg.

Dairy products also contain vitamin B12. One glass of milk would give you half your daily requirement requirement (1.24mcg) and one slice of cheese (20g) would provide one-fifth (0.4mcg).

A glass of milk would provide half the vitamin B12 you need in a day.
AntGor/Shutterstock

Vitamin B12 can be found in trace amounts in spinach and fermented foods, but these levels aren’t high enough to meet your nutritional needs. Mushrooms, however, have consistently higher levels, with shiitake mushrooms containing 5mcg per 100g.

To meet the shortfall of vitamin B12 from reducing red meat intake, you would need to eat 75g kangaroo per day or have a glass of milk (200ml) plus a slice of cheese (20g). Alternatively, a handful of dried shiitake mushrooms in your salad or stir-fry would fulfil your requirements.

Don’t forget about fibre

A recent study found fibre intakes of around 25 to 29g a day were linked to lower rates of many chronic diseases such as coronary heart disease, type 2 diabetes, stroke and bowel cancer.

Yet most Australian adults currently have low dietary fibre levels of around 20g a day.

By making some of the changes above and increasing your intake of meat alternatives such as legumes, you’ll also be boosting your levels of dietary fibre. Substituting 100g of lentils will give you an extra 5g of fibre per day.

With some forward planning, it’s easy to swap red meat for other animal products and non-meat alternatives that are healthier and more environmentally sustainable.The Conversation

Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, University of South Australia

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

Health check: can eating certain foods make you smarter?



File 20190325 36273 au864m.jpg?ixlib=rb 1.1
Green vegetables, nuts and berries are among the foods that could improve our brain function.
From shutterstock.com

Margaret Morris, UNSW and Michael Kendig, UNSW

Trying to keep up with what constitutes a “healthy” diet can be exhausting. With unending options at the supermarket, and diet advice coming from all directions, filling your shopping trolley with the right things can seem an overwhelming task.

For a long time we’ve known diet is key to maintaining physical health.

But emerging evidence indicates diet quality also plays a critical role in our cognitive function.

We’re learning some of the best things to eat in this regard include vegetables, nuts and berries, foods containing “good fats” and, possibly, fermented foods.

As well as potentially improving our brain function, eating these sorts of foods could improve our mental well-being – and could even help the planet, too.




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Diet and brain function

In the face of rising obesity rates, over the past couple of decades, researchers have questioned whether increased weight, or poor diet, could influence cognition. They have since looked at what sorts of diets might impair or improve the function of our brains.

Long term follow-up studies show obesity is associated with mild impairments in several domains of cognitive function, including short-term memory, attention and decision-making.

Research has also shown short-term memory is poorer in people who report eating more saturated fat and sugar.

Conversely, the Mediterranean diet has been associated with better brain health and maintenance of cognitive abilities into older age. A Mediterranean diet is based on vegetables, whole grains, legumes and nuts, with healthy fats such as olive oil. Intake of red meat, saturated fats and sugar is limited.

A healthy diet has many elements, so let’s look at what particular foods might explain these benefits.

Vegetables, nuts and berries

Evidence indicates eating more vegetables slows the gradual decline in cognitive abilities that occurs naturally as we age.

While all veggies are likely to contribute, those in the cruciferous (Brassicaceae) family may confer particular benefits through their high fibre, folate, potassium and vitamin content. Vegetables in this family include broccoli, cauliflower, brussels sprouts, and fad favourites kale and rocket.

Interestingly, while there’s good evidence for the protective role of vegetables, there’s less evidence when it comes to fruit.

Research has shown a healthy diet can improve cognitive functions such as learning and memory.
From shutterstock.com

Berries, though, contain high levels of antioxidants. These compounds protect the body by scavenging harmful free radicals and reducing inflammation. Together these functions are likely to protect our cognitive ability.

Studies in rats, and in older people with mild cognitive impairment, indicate supplementing diets with berries improves performance in various memory tasks.

Nuts, meanwhile, are excellent sources of monounsaturated and polyunsaturated fats, minerals and vitamins. Studies in animals have shown the addition of nuts improves learning and memory. Emerging evidence in humans suggests consuming nuts within a Mediterranean-style diet improves measures of cognition, such as the capacity for verbal reasoning.

Healthy fats

Healthy diets such as the Mediterranean diet are also characterised by foods such as oily fish, avocados, olive oil and small amounts of animal-derived fats (such as from red meat).

One of our experiments in rats showed diets high in saturated fat from lard or high in sugar led to memory impairments, whereas an oil-based diet high in polyunsaturated fats didn’t.




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Importantly, rats fed these different diets did not differ in their total energy intake – only the type of fat and sugar varied.

While we can’t comment directly on the effects in humans, these findings suggest eating excess sugar, or animal-based fats, may negatively impact cognition.

Fermented foods

For thousands of years humans have prolonged the life of foods through fermentation, which increases the proportion of Lactobacillus and other healthy gut bacteria.

Kombucha and kefir are trendy right now, but other popular fermented foods include kimchi, miso, yoghurt and sauerkraut. Intake of these foods is thought to maintain the diversity of the gut microbiome.




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Interest in the potential cognitive effects of fermented foods stems from emerging evidence for the importance of the gut microbiota in cognition and health.

It’s well known that a poor diet can reduce the diversity of the gut microbiome. Our work in rats has shown the cognitive impairments produced by exposure to an unhealthy “cafeteria” diet – a Western-style diet high in saturated fat and sugar – are linked to changes in the gut microbiome.

Beyond cognition

It’s not possible to attribute “miracle” properties to one food group alone. We suggest a balanced, varied diet is the best approach to sustain not only brain health, but heart health too.

And there may be other reasons to seek out these foods. A newly published study showed eating fruit and vegetables improved mental well-being. Subjects tended to feel happier, less worried, and reported higher levels of overall life satisfaction.

The link between diet quality and better mental health is now well-established.

The recently published EAT-Lancet report adds a further compelling reason to eat healthily: the environment. This commission argued for a “planetary health” diet – akin to the Mediterranean diet – consisting of whole grains, vegetables, fruits, nuts and dairy, healthy fats, with low animal protein and few processed foods.

It is thought that shifting to such a diet, together with reducing food waste and adopting more sustainable food production systems, will minimise environmental damage and safeguard individual health.

The central message is the health of individuals and of the planet are inextricably linked, and this requires a rethink of global food systems.




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Overhauling food systems – and individual food habits – will not be simple while foods high in fat and sugar are so readily available and relatively cheap.

Nonetheless, recognising that eating well might benefit the planet, as well as the body and brain, might motivate people to change their dietary habits.The Conversation

Margaret Morris, Professor of Pharmacology, Head of Pharmacology, UNSW and Michael Kendig, Postdoctoral Research Fellow, UNSW

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

Health check: is moderate drinking good for me?



File 20190307 82669 qqvs4x.jpg?ixlib=rb 1.1
We previously thought moderate drinking could be good for our health. There’s now evidence that says the opposite.
From shutterstock.com

Hassan Vally, La Trobe University

For the past three decades or so, the conventional wisdom has been that drinking alcohol at moderate levels is good for us.

The evidence for this has come from many studies that have suggested the death rate for moderate drinkers is lower than that for non-drinkers. In other words, we thought moderate drinkers lived longer than those who didn’t drink at all.

This phenomenon has been communicated with great impact by the J-shaped curve that shows death rates fall as you move from non-drinking to moderate drinking, before rising again as drinking levels increase.




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Most of us embraced these studies with enthusiasm. But the findings were probably too good to be true. The problem has always been the potential mixing of many other variables – called confounding factors – with drinking.

The concern was that non-drinkers as a group in many of these previous studies were different to moderate drinkers in many ways in addition to their drinking. Non-drinkers may have been unhealthier to begin with (hence not taking up drinking in the first place) or they may have included recovering alcoholics with poor health.

These confounding factors may have made moderate drinkers look healthier than they actually were (relative to non-drinkers) and thus have led us to associate moderate drinking with better health.




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More recent studies have been able to address this challenge of separating out the effect of drinking on health, independent of other confounding factors. And these newer studies tell us moderate drinking is probably not good for us at all.

Instead of the J-shaped curve described previously, the most recent evidence is showing a curve that continues on an upward trajectory.

As you increase your level of drinking beyond not drinking at all, for all levels of drinking, your health outcomes worsen. The curve starts off relatively flat, before rising dramatically, indicating much higher rates of early death as drinking levels increase.

So what is the health cost of moderate drinking?

If we look a recent Lancet study that addressed this issue, we can start to make sense of this cost. This suggests that if you drink one alcoholic drink per day you have a 0.5% higher risk of developing one of 23 alcohol-related health conditions.

But risk expressed in this way is difficult to interpret. It’s only when we convert this to an absolute risk that we can begin to understand the actual magnitude of this risk to our health. It translates to four more illnesses* per 100,000 people due to alcohol, which is actually a pretty small risk (but an increased risk nonetheless).

While the health implications of moderate drinking have been a point of contention, it’s clear drinking excessively isn’t good.
From shutterstock.com

This risk estimation assumes several things, including that you drink alcohol every single day, so you would expect the risk to be smaller for those who drink every other day or only occasionally.

The latest evidence suggests the health cost of light to moderate drinking, if there is one, is quite small. What was previously thought to be a marginal benefit of moderate alcohol drinking is now considered a marginal cost to health.




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So for you as an individual, what does this new evidence mean?

Maybe it means having to lose the contentedness you have felt as you drink your evening glass of wine, believing it was also improving your health.

Or maybe this new evidence will give you the motivation to reduce your drinking, even if you are only a moderate drinker.

Of course, if you get pleasure from drinking responsibly, and you have no intention of changing your drinking habits, then you will have to consider and accept this potential cost to your health.

But remember, the evidence is still incontrovertible that drinking high levels
of alcohol is very bad for you. It will shorten the length of your life and affect the quality of your life and those around you.

Correction: this article originally said one alcoholic drink per day equated to four more deaths – rather than illnesses – per 100,000 people due to alcohol.The Conversation

Hassan Vally, Senior Lecturer in Epidemiology, La Trobe University

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

Eat your vegetables – studies show plant-based diets are good for immunity



File 20190306 48441 rapg73.jpg?ixlib=rb 1.1
We’ve been told there are many benefits of eating our veggies. Could they improve our immune system too?
From shutterstock.com

Yasmine Probst, University of Wollongong and Joel Craddock, University of Wollongong

The number of people in Australia who follow vegetarian or plant-based diets is growing rapidly. People might choose to be vegetarian for ethical, cultural or health-related reasons.

While not all vegetarians are necessarily following a healthy diet, research shows vegetarianism can have many benefits for health. One we’re learning more about is its potential to strengthen our immune systems.

We’re still working out what aspects of a vegetarian diet may be responsible for this – whether it’s the lack of meat or the emphasis on plant-based foods.

But we think the higher volume of foods including fruits, vegetables and legumes seen in vegetarian diets is likely to have a lot to do with any associated health benefits.




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What do vegetarians eat?

Vegetarian diets are comprised of combinations of fruit, vegetables, whole grains, nuts and seeds, legumes and, for some, dairy and eggs.

There are many types of vegetarian eating patterns, from vegan (no animal products) through to lacto-ovo (some animal products such as eggs and dairy). But each avoids eating meat.

There are also a few semi-vegetarian approaches which include eating small amounts of some meats. People who primarily follow a vegetarian diet but include fish are referred to as pescetarian, while those who occasionally eat other forms of meat are considered flexitarian.

Importantly, not all vegetarians follow a healthy and balanced diet. Many won’t eat the recommended daily servings of fruit and vegetables, and will consume too much junk food.

But studies show that balanced vegetarian eating patterns could be good for our immune system and the related response of the body.

Defending from attack

Our bodies are faced with daily challenges such as getting rid of toxic chemicals and defending against nasty viruses. The immune system is “switched on” in response to these attacks.

Having a healthy immune system is important, as it prevents us from becoming sick. A healthy immune system can be supported by a number of lifestyle factors including adequate sleep, healthy body weight and regular physical activity. It can also be substantially affected by the foods we eat and drink.

Some research has found following a vegetarian diet could improve our immune systems.
From shutterstock.com

People following vegetarian diets tend to have lowered levels of white blood cells, our natural defender cells. This is the case for vegetarian diets including vegan, lacto-vegetarian and lacto-ovo vegetarian.

Having very low levels of these cells is not ideal as it can affect the body’s ability to fight infection. However, having just the right number of white cells within a healthy range may reduce your chances of getting sick.

An added shield of protection

As well as helping the immune system, vegetarian diets may also help our body with a related process called inflammation. Vegetarian diets have been shown to prevent inflammation due to the antioxidant components within the foods.

Inflammation occurs when the body releases cells to attack unwanted pathogens or respond to injury. It may result in redness to an area of the body or the release of certain chemicals inside our bodies. Inflammation is a protective measure that the body uses to stay as healthy as it can.




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People who follow vegetarian diets have lower levels of some of these chemicals (called C-reactive protein and fibrinogen) compared to people following a non-vegetarian diet.

This means people maintaining a vegetarian diet long-term are at a lower risk of getting type 2 diabetes, heart disease or even some cancers. Each of these chronic diseases is associated with increased inflammation in the body. This is shown in blood tests by increased levels of C-reactive protein, as this is a signal of systemic inflammation.

The reason why vegetarians have lowered levels of inflammation remains to be fully understood.

We suspect the high amount of fruits, vegetables, whole grains, nuts and seeds are helping. These foods are full of important nutrients including fibres, vitamins, minerals and compounds called phytochemicals.

All of these nutrients have been shown to improve levels of inflammation in the long term and may influence the body’s immune response as an added bonus.

Should I switch to a vegetarian diet?

Going vegetarian may not be for everyone.

And it’s unwise to start a new eating pattern without understanding the potential impacts it can have on your health.

Vegetarian diets that are inappropriately balanced can lead to an increased risk of iron, zinc and vitamin B12 deficiencies. This can be detrimental to overall health, particularly if followed for extended periods of time.

The risks may be greater for certain groups of people who have added nutrient needs due to life stage, gender or for another health-related reason.

So vegetarian eating should always be undertaken carefully and under professional guidance, preferably that of a dietitian, to minimise these risks.




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But importantly, only 5.1% of the Australian population eat the recommended amount of fruit and vegetables – five serves of vegetables and two serves of fruit each day.

So whether you’re vegetarian or not, focusing on incorporating more plant-based foods into your diet is worthwhile. We’re constantly learning more ways this is good for your health.The Conversation

Yasmine Probst, Senior lecturer, School of Medicine, University of Wollongong and Joel Craddock, PhD Candidate, University of Wollongong

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

Health check: will eating nuts make you gain weight?



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Nuts contain “good” fats.
From shutterstock.com

Elizabeth Neale, University of Wollongong; Sze-Yen Tan, Deakin University, and Yasmine Probst, University of Wollongong

The Australian Dietary Guidelines recommend we eat 30g of nuts – a small handful – each day. But many of us know nuts are high in calories and fat.

So should we be eating nuts or will they make us gain weight?

In short, the answer is yes, we should eat them, and no, they won’t make us gain weight if eaten in moderate amounts. The fats in nuts are mostly the “good” fats. And aside from that, our bodies don’t actually absorb all the fat found in nuts. But we do absorb the nutrients they provide.




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Dietary fat: friend or foe?

Nuts do contain fat, and the amount of fat varies between nut types. For example, a 30g serving of raw cashews or pistachios contains around 15g of fat, whereas the same amount of raw macadamias contains around 22g of fat.

There are different kinds of fats in our diet and some are better for us than others. Nuts contain mainly monounsaturated and polyunsaturated fats. These types of fats are known as “good fats”. They can help lower cholesterol when we eat them in place of saturated fats.

The type of fats present varies between nuts. For example, walnuts are rich in polyunsaturated fats, whereas other types of nuts such as hazelnuts and macadamias have more monounsaturated fat.

What the evidence says

Even if the type of fat in nuts is good for us, they are still high in fat and calories. But this doesn’t mean we should be avoiding them to manage our weight.

Studies that looked at people’s eating habits and body weight over a long period have found people who regularly eat nuts tend to gain less weight over time than people who don’t.

Nuts are a healthier option for a snack than many processed alternatives.
From shutterstock.com

We see a similar pattern in clinical studies that asked people to include nuts in their diets and then looked at the effects on body weight.

A review of more than 30 studies examined the effects of eating nuts on body weight. It did not find people who ate nuts had increased their body weight, body mass index (BMI), or waist circumference, compared to a control group of people who did not eat nuts.

In fact, one study found that when people ate a pattern of food aimed at weight loss, the group of people who ate nuts lost more body fat than those who didn’t eat nuts.




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Let’s nut this out

There are several possible explanations for why eating nuts doesn’t seem to lead to weight gain.

  1. We don’t absorb all of the fat in nuts: The fat in nuts is stored in the nut’s cell walls, which don’t easily break down during digestion. As a result, when we eat nuts, we don’t absorb all of the fat. Some of the fat instead is passed out in our faeces. The amount of calories we absorb from eating nuts might be between 5% and 30% less that what we had previously thought.

  2. Nuts increase the amount of calories we burn: Not only do we not absorb all the calories in nuts, but eating nuts may also increase the amount of energy and fat we burn. It’s thought this may partially be explained by the protein and unsaturated fats in nuts, although we don’t yet know exactly how this occurs. Increases in the number of calories burnt can help us maintain or lose weight.

  3. Nuts help us feel full for longer: As well as fat, nuts are rich in protein and fibre. So, nuts help to keep us feeling full after we eat them, meaning we’re likely to eat less at later meals. Recent studies have also suggested providing people with nuts helps improve the overall quality of the types of foods they eat. This may be because nuts replace “junk foods” as snacks.

  4. People who eat nuts have healthier lifestyles in general: We can’t rule out the idea that eating nuts is just a sign of a healthier lifestyle. However, randomised controlled trials, which can control for lifestyle factors like eating habits, still find no negative effect on body weight when people eat nuts. This means the favourable effects of nuts are not just the result of nut eaters having healthier lifestyles – the nuts themselves play a role.




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Want to improve your mood? It’s time to ditch the junk food


Overall, the evidence suggests nuts are a healthy snack that can provide us with many of the nutrients our bodies need. We can confidently include the recommended 30g of nuts a day in a healthy diet, without worrying about the effect they will have on our waistlines.The Conversation

Elizabeth Neale, Career Development Fellow (Lecturer), University of Wollongong; Sze-Yen Tan, Senior Lecturer in Nutrition Science, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, and Yasmine Probst, Senior lecturer, School of Medicine, University of Wollongong

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

Want to improve your mood? It’s time to ditch the junk food



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Eating a healthy diet fuels our brain cells, fights inflammation and helps produce the chemicals that make us happy.
Antor Paul

Megan Lee, Southern Cross University

Worldwide, more than 300 million people live with depression. Without effective treatment, the condition can make it difficult to work and maintain relationships with family and friends.

Depression can cause sleep problems, difficulty concentrating, and a lack of interest in activities that are usually pleasurable. At its most extreme, it can lead to suicide.




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Depression has long been treated with medication and talking therapies – and they’re not going anywhere just yet. But we’re beginning to understand that increasing how much exercise we get and switching to a healthy diet can also play an important role in treating – and even preventing – depression.

So what should you eat more of, and avoid, for the sake of your mood?

Ditch junk food

Research suggests that while healthy diets can reduce the risk or severity of depression, unhealthy diets may increase the risk.

Of course, we all indulge from time to time but unhealthy diets are those that contain lots of foods that are high in energy (kilojoules) and low on nutrition. This means too much of the foods we should limit:

  • processed and takeaway foods
  • processed meats
  • fried food
  • butter
  • salt
  • potatoes
  • refined grains, such as those in white bread, pasta, cakes and pastries
  • sugary drinks and snacks.

The average Australian consumes 19 serves of junk food a week, and far fewer serves of fibre-rich fresh food and wholegrains than recommended. This leaves us overfed, undernourished and mentally worse off.

Here’s what to eat instead

Mix it up.
Anna Pelzer

Having a healthy diet means consuming a wide variety of nutritious foods every day, including:

  • fruit (two serves per day)
  • vegetables (five serves)
  • wholegrains
  • nuts
  • legumes
  • oily fish
  • dairy products
  • small quantities of meat
  • small quantities of olive oil
  • water.



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This way of eating is common in Mediterranean countries, where people have been identified as having lower rates of cognitive decline, depression and dementia.

In Japan, a diet low in processed foods and high in fresh fruit, vegetables, green tea and soy products is recognised for its protective role in mental health.

How does healthy food help?

A healthy diet is naturally high in five food types that boost our mental health in different ways:

Complex carbohydrates found in fruits, vegetables and wholegrains help fuel our brain cells. Complex carbohydrates release glucose slowly into our system, unlike simple carbohydrates (found in sugary snacks and drinks), which create energy highs and lows throughout the day. These peaks and troughs decrease feelings of happiness and negatively affect our psychological well-being.

Antioxidants in brightly coloured fruit and vegetables scavenge free radicals, eliminate oxidative stress and decrease inflammation in the brain. This in turn increases the feelgood chemicals in the brain that elevate our mood.




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Omega 3 found in oily fish and B vitamins found in some vegetables increase the production of the brain’s happiness chemicals and have been known to protect against both dementia and depression.

Salmon is an excellent source of omega 3.
Caroline Attwood

Pro and prebiotics found in yoghurt, cheese and fermented products boost the millions of bacteria living in our gut. These bacteria produce chemical messengers from the gut to the brain that influence our emotions and reactions to stressful situations.

Research suggests pro- and prebiotics could work on the same neurological pathways that antidepressants do, thereby decreasing depressed and anxious states and elevating happy emotions.

What happens when you switch to a healthy diet?

An Australian research team recently undertook the first randomised control trial studying 56 individuals with depression.

Over a 12-week period, 31 participants were given nutritional consulting sessions and asked to change from their unhealthy diets to a healthy diet. The other 25 attended social support sessions and continued their usual eating patterns.

The participants continued their existing antidepressant and talking therapies during the trial.

At the end of the trial, the depressive symptoms of the group that maintained a healthier diet significantly improved. Some 32% of participants had scores so low they no longer met the criteria for depression, compared with 8% of the control group.




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The trial was replicated by another research team, which found similar results, and supported by a recent review of all studies on dietary patterns and depression. The review found that across 41 studies, people who stuck to a healthy diet had a 24-35% lower risk of depressive symptoms than those who ate more unhealthy foods.

These findings suggest improving your diet could be a cost-effective complementary treatment for depression and could reduce your risk of developing a mental illness.The Conversation

Megan Lee, Academic Tutor and Lecturer, Southern Cross University

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

What’s behind the increase in bowel cancer among younger Australians?



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Bowel cancer was the second most commonly diagnosed cancer in Australia in 2017.
from shutterstock.com

Suzanne Mahady, Monash University; Eleonora Feletto, Cancer Council NSW, and Karen Canfell, UNSW

Bowel cancer mostly affects people over the age of 50, but recent evidence suggests it’s on the rise among younger Australians.

Our study, published recently in Cancer Epidemiology, Biomarkers and Prevention, found the incidence of bowel cancer, which includes colon and rectal cancer, has increased by up to 9% in people under 50 from the 1990s until now.

Our research examined all recorded cases of bowel cancer from the past 40 years in Australians aged 20 and over. Previous studies assessing bowel cancer incidence in young Australians have also documented an increase in the younger age group.




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Bowel cancer includes cancer of the colon and rectum.
Wikimedia Commons

This trend is also being seen internationally. A study from the United States suggests an increase in bowel cancer incidence in people aged 54 and younger. The research shows rectal cancer incidence increased by 3.2% annually from 1974 to 2013 among those aged age 20-29.

Bowel cancers are predicted to be the third most commonly diagnosed cancer in Australia this year. In 2018, Australians have a one in 13 chance of being diagnosed with bowel cancer by their 85th birthday.

Our study also found bowel cancer incidence is falling in older Australians. This is likely, in part, to reflect the efficacy of the National Bowel Cancer Screening Program, targeted at those aged 50-74. Bowel cancer screening acts to reduce cancer incidence, by detecting and removing precancerous lesions, as well as reducing mortality by detecting existing cancers early.

This is important, as bowel cancer has a good cure rate if discovered early. In 2010 to 2014, a person diagnosed with bowel cancer had a nearly 70% chance of surviving the next five years. Survival is more than 90% for people who have bowel cancer detected at an early stage.

That is why screening is so effective – and we have previously predicted that if coverage rates in the National Bowel Screening Program can be increased to 60%, around 84,000 lives could be saved by 2040. This would represent an extraordinary success. In fact, bowel screening has potential to be one of the greatest public health successes ever achieved in Australia.

Why the increase in young people?

Our study wasn’t designed to identify why bowel cancer is increasing among young people. However, there are some factors that could underpin our findings.

The increase in obesity parallels that of bowel cancer, and large population based studies have linked obesity to increased cancer risk.




Read more:
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Unhealthy lifestyle behaviours, such as increased intake of highly processed foods (including meats), have also been associated with increased bowel cancer risk. High quality studies are needed to explore this role further.

Alcohol is also thought to be a contributor to increasing the risk of bowel cancer.

Alcohol is thought to contribute to an increased risk of bowel cancer.
from shutterstock.com

So, should we be lowering the screening age in Australia to people under the age of 50?

Evaluating a cancer screening program for the general population requires a careful analysis of the potential benefits, harms, and costs.

A recent Australian study modelled the trade-offs of lowering the screening age to 45. It showed more cancers would potentially be detected. But there would also be more colonoscopy-related harms such as perforation (tearing) in an extremely small proportion of people who require further evaluation after screening.

A lower screening age would also increase the number of colonoscopies to be performed in the overstretched public health system and therefore could have the unintended consequence of lengthening colonoscopy waiting times for people at high risk.




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How to reduce bowel cancer risk

One of the most common symptoms of bowel cancer is rectal bleeding. So if you notice blood when you go to the toilet, see your doctor to have it checked out.

A healthy lifestyle including adequate exercise, avoiding smoking, limiting alcohol intake and eating well, remains most important to reducing cancer risk.

Aspirin may also lower risk of cancer, but should be discussed with your doctor because of the potential for side effects including major bleeding.

Most importantly, we need to ensure eligible Australians participate in the current evidence-based screening program. Only 41% of the population in the target 50-74 age range completed their poo tests in 2015-2016. The test is free, delivered by post and able to be self-administered.The Conversation

Suzanne Mahady, Gastroenterologist & Clinical Epidemiologist, Senior Lecturer, Monash University; Eleonora Feletto, Research fellow, Cancer Council NSW, and Karen Canfell, Adjunct professor, UNSW

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

Health Check: what causes bloating and gassiness?



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One in six healthy people report problems with bloating.
Alice Day/Shutterstock

Vincent Ho, Western Sydney University

Your trousers fit when you put them on in the morning. But come mid-afternoon, they’re uncomfortably tight – and you didn’t even overdo it at lunchtime. Sound familiar?

Around one in six people without a health problem and three in four people with irritable bowel syndrome (IBS) report problems with bloating. In fact, for people with IBS and constipation, bloating is their most troublesome symptom.




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Bloating is, of course, a feeling of increased abdominal pressure, usually related to gas. It may or may not be accompanied by visible enlargement of the waist (known as abdominal distension).

But contrary to popular belief, bloating and abdominal distention isn’t caused by an excessive production of gas in the intestines.

What causes intestinal gas?

Gas in the upper gut can come from swallowed air, chemical reactions (from neutralising acids and alkali) triggered by food, and dissolved gas moving from the bloodstream into the gut.

Food products that are poorly absorbed in the small intestine can travel lower down to the large intestine where they’re fermented by bacteria. This process can produce carbon dioxide, hydrogen or methane gas.

Gas from the gut can come out through belching or passing wind, or by being absorbed into the blood or consumed by bacteria.

How much wind is normal?

Back in 1991, researchers in the UK tracked the farts of ten healthy volunteers. The volume of gas they expelled in a day varied from 214 mls (on a low-fibre diet) to 705 mls (on a high fibre diet).




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The participants passed wind an average of 14 to 18 times per day, and it was comprised mainly of carbon dioxide and hydrogen.

In the fasting state, the healthy gastrointestinal tract contains around 100 mls of gas which is distributed almost equally among six segments of the gut: the stomach, small intestine, ascending colon, transverse colon, descending colon and lower (pelvic) colon.


Tefi/Shutterstock

After eating, the volume of gas in the gut can increase by about 65% and tends to be located around the pelvic colon.

As the stomach stretches and small bowel is stimulated, the passage of gas accelerates and you might feel the urge to fart.

But for people with a high-fat diet, fats inside the small bowel can delay this passage and make you retain the gas.

Bloaters don’t produce more gas

A 1975 study compared the amount of intestinal gas between people who reported being bloated and those who said they were not.

The researchers pumped (inert) gas through a tube directly into the participants’ intestines at a relatively high flow of 45 mls per minute. Then they recovered the gas via a plastic tube from their rectum.

The researchers found no difference in the levels of gas collected between the bloating and healthy subjects.

Not everyone who feels bloated will have a distended stomach.
siam.pukkato/Shutterstock

More recent research using abdominal CT scans has shown that people with bloating have similar volumes of intestinal gas as those who don’t feel bloated.

Likewise, although people with IBS experience more abdominal distention, they do not produce more intestinal gas than other people.

This leads us to believe the volume of gas in the gut itself isn’t the main mechanism for bloating.

When gas gets trapped

Most people tolerate intestinal gas really well because they can propel and evacuate gas very efficiently. As a result, only a relatively small amount of gas remains inside the gut at a given time.

In one study, researchers pumped just over 1.4 litres of gas in two hours into the mid-small bowel of healthy volunteers. This led to only a very small change in waist circumference: no more than 4mm.

On the other hand, people with abdominal conditions such as IBS or functional dyspepsia (indigestion), show impaired gas transit – in other words, the gas ends up being trapped in different parts of the bowel rather than moving along easily.




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Studies show people with abdominal conditions tend to retain a relatively large proportion of gas pumped into the mid small bowel. They may even have notable increases in waist circumference without any gas being pumped in.

This impairment was confirmed in a study comparing 20 participants with IBS to a control group of 20 healthy participants. All received gas pumped directly into the mid-small bowel.

Some 90% of IBS participants retained the gas in their intestines compared to only 20% of control subjects. The researchers found abdominal distension was directly correlated with gas retention.

Some people also have problems evacuating this gas, or farting. People with IBS and chronic constipation, for instance, may have difficulty relaxing and opening their anal sphincter to release farts.

This can lead to intestinal gas retention and symptoms of bloating, abdominal pain and distension.

Pain without looking bloated

Despite feeling extremely bloated, some people have minimal or no distension of their stomach.

Research among people with IBS suggests this pain and discomfort may be due to a heightened sensitivity in the gut when a section of the abdomen stretches.

In fact, one study found those with bloating alone had more abdominal pain than those who had symptoms of bloating and abdominal distension.

If you’re sensitive to this stretching, are unable to move gas throughout your gut, and can’t get rid of it, you’re likely to have bloating and pain, whether or not there’s any visual sign.




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The Conversation


Vincent Ho, Senior Lecturer and clinical academic gastroenterologist, Western Sydney University

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