Health Check: is margarine actually better for me than butter?



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The type of fatty acid is what’s most important when choosing a spread.
from http://www.shutterstock.com.au

Evangeline Mantzioris, University of South Australia

Only 20 years ago butter was the public villain – contributing to raised cholesterol levels and public concern over an increased risk of heart disease. Now this public perception seems to have been reversed, and reality cooking shows seem to use butter in every recipe. But what has caused this shift in perceptions and is it based on scientific evidence?

In the domestic market more people buy margarine than butter, with 27% of respondents in an ABS survey eating margarine the day before, and 15% consuming butter.


Read more: Eat food, not nutrients: why healthy diets need a broad approach


Do we still need to be concerned about butter’s links to heart disease, and is there any evidence to suggest butter is better for our health compared to margarine? To answer this we first need to look more closely at the make-up of butter and margarine.

Where do our favourite yellow spreads come from?

Butter is made from the processing of cream. The cream is churned until the liquid (buttermilk) separates from the fat solids. These fat solids are then rinsed, a little salt added, and shaped to form the butter we all love.

Margarine was first developed in France by Napoleon as a substitute for butter to feed the armed forces and lower classes. Margarine is made from vegetable oils, beta-carotene (added for colour), emulsifiers (to help the oil and water mix), salt and flavours (which can include milk solids). Vitamins A and D are also added to the same level present in butter.

We have Napoleon to thank for the advent of margarine.
from shutterstock.com

Any diet app will tell you margarine has about 10-15% fewer kilojoules than butter. But whether this is significant will largely depend on the amount you consume each day.

A national nutrition survey indicates the average person over 19 years consumes 20 grams a day of spreads (either butter or margarine), which equates to a difference of 100kj. This difference is largely insignificant in a usual daily intake of 8700kj/day.

It’s all in the fatty acids

The significant nutritional difference actually lies in the fatty acid profiles of the two products. The health differences between butter and margarine are based on the presence of different types of fats.

There are three types of fats in our food: saturated fat, monounsaturated fats and polyunsaturated fats. The difference between these lies in their chemical structure. The structure of saturated fats has no double bonds in between the carbon atoms, monounsaturated fats have one double bond between the carbon atoms, and polyunsaturated fats have two or more double bonds between the carbon atoms.

These subtle differences in structure lead to differences in the way our body metabolises these fats, and hence how they affect our health, in particular our heart health.


Read more: Viewpoints – is saturated fat really the killer it’s made out to be?


Margarine can be made from a number of different oils. If coconut oil is used the margarine will be mainly saturated fat, if sunflower oil is used it will mainly be a polyunsaturated fat, and if olive oil or canola oil is used it will mainly be a monounsaturated fat.

Butter, derived from dairy milk, is mainly saturated fat, and the main saturated fats are palmitic acid (about 31%) and myristic acid (about 12%). Studies have shown these raise blood cholesterol levels.

While there is debate in the scientific world about the relative contributions of saturated fats (and the different types of saturated fatty acids) to heart disease, the consensus is that replacing saturated fats with monounsaturated or polyunsaturated fats will lower the risk of heart disease.

The Australian Dietary Guidelines and World Health Organisation recommend the lowering of saturated fats to below 10% of daily energy intake. Depending on the overall quality of your diet and intake of saturated fats, you may need to swap your butter for margarine.

Check the labels

Extra-virgin oil protects against heart disease.
from shutterstock.com

There is strong evidence extra-virgin olive oil (a monounsaturated fat) provides strong benefits for heart disease protection – but there isn’t enough extra-virgin olive oil in margarine products to confer this benefit. Using olive-oil-based margarines is going to contribute very little to your daily intake of extra-virgin olive oil.

And this is why it’s confusing for the consumer – despite a margarine being labelled as being made from olive oil, it may contain only small amounts of olive oil and not be as high in monounsaturated fats as expected. It’s best to read the nutrition information panel to determine which margarine is highest in monounsaturated fats.

Another point of difference between butter and margarine is that margarine may contain plant sterols, which help reduce cholesterol levels.

At the end of the day, if you consume butter only occasionally and your diet closely adheres to the Australian guidelines for healthy eating, there is no harm in continuing to do so.

Another option to consider would be the butter blends. These provide the taste of butter while reducing saturated fat intake to half, and they are easier to spread. Of course, if you consume lots of butter, swapping for a low saturated fat margarine is your healthier option – perhaps reserve the butter for special occasions.

If you’re concerned about saturated fat levels in your diet, you should read the nutrition information panel to determine which margarine is lowest in saturated fat, regardless of which oil is used in the product.

The ConversationAs always, people need to base their decision on their family and medical history and obtain advice from their dietitian or GP.

Evangeline Mantzioris, Lecturer in Nutrition, University of South Australia

This article was originally published on The Conversation. Read the original article.

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Farming the suburbs – why can’t we grow food wherever we want?



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Some local councils are more tolerant than others in allowing residents to grow food where they want.
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Jennifer Kent, University of Sydney

Food provides the foundations for human flourishing and the fabric of sustainability. It lies at the heart of conflict and diversity, yet presents opportunities for cultural acceptance and respect. It can define neighbourhoods, shape communities, and make places.

In parts of our cities, residents have embraced suburban agriculture as a way to improve access to healthier and more sustainably produced food. Farming our street edges and verges, vacant land, parks, rooftops and backyards is a great way to encourage an appreciation of locally grown food and increase consumption of fresh produce.

Despite these benefits, regulations, as well as some cultural opposition, continue to constrain suburban agriculture. We can’t grow and market food wherever we like, even if it is the sustainable production of relatively healthy options.

While good planning will be key to a healthier, more sustainable food system, planning’s role in allocating land for different uses across the city also constrains suburban agriculture.

Two steps towards healthier food systems

Making our food systems healthier and more sustainable requires a two-step approach.

  • First, we need to fortify the parts of the system that enable access to healthy food options.

  • Second, we need to disempower elements that continuously expose us to unhealthy foods.

Although food is a basic human need, the way we consume food in many countries, including Australia, is harmful to the environment and ourselves. Many of us don’t eat enough fresh and unprocessed foods. The foods we do eat are often produced and supplied in carbon-intensive and wasteful ways.

Primarily through land-use zoning, town planners can help to shape sustainable and healthy food systems. For example, good planning can:

  • protect peri-urban agricultural lands;

  • encourage farmers’ markets, roadside stalls and community gardens;

  • prevent the location of fast-food outlets near schools; and

  • even help regulate food advertising environments.

Why have land-use zones?

Modern town planning originated in the 19th century out of the need and ability to separate unhealthy, polluting uses from the places where people lived.

This was a direct response to the Industrial Revolution, which brought with it both an upscaling of the noisy, smelly and dirty uses to be avoided, and the emergence of new ways to travel relatively long distances away from these uses.

As a result, our urban areas are made up of a mosaic of what we call zones. Within each zone, certain uses are permitted and others are prohibited. If a piece of land is zoned as commercial, for example, that land can be used for a shop, but not for a house.

While this might seem logical to us today, to those living in housing scattered among the factories and tanneries of Manchester in the 1800s it would have been quite radical.

It is this function of planning that means we cannot grow food anywhere in the city. Instead, we have regulations that attempt to ensure related activities occur only in areas where such a use is compatible with the surrounding uses.

Where food gardens are next to roads these should not carry heavy traffic, which could be a source of contamination.
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Incompatibility might relate to safety. For example, in some cities it is prohibited to locate a community garden on a main traffic-generating road due to concerns about contamination of produce.

It could also be related to amenity. For example, in some areas local produce cannot be sold on the roadside due to concerns about creating additional traffic and parking.

These are two fairly obvious examples, but problems arise when definitions of what is safe and amenable differ within the community. Does a verge planted with an over-enthusiastic pumpkin vine detract from or enhance the visual appeal of the street? Should a locality embrace a roadside produce stall even if it means traffic is slowed and parking is less available?

How do we resolve planning conflicts?

Town planners attempt to grapple with these issues by developing new policies and regulations to respond to changing demands, or by assessing applications for food growing and distribution on a case-by-case basis.

In cities that are rapidly densifying, and in a cultural environment where growing one’s own produce is enjoying a renaissance, it’s not surprising some local authorities are struggling to keep up.

This struggle is ostensibly the result of local authorities failing to recognise and prioritise their role in supporting sustainable and healthy food systems. There are immense benefits – biophysical, economic and social – to be gained from local government giving priority to urban agriculture.

Yet a recent study of the content of local community strategic plans across New South Wales found that only 10% of strategies mentioned anything about food systems as a community priority. In this sense, Australia is part of an international trend.

The ConversationSurprisingly, the local authorities in New South Wales doing the most for better food systems were regional councils. These saw food security and the opportunities presented by local food production as urgent issues. There is obviously room for our metropolitan councils to catch up and capitalise on increased cultural interest in farming our suburbs.

Jennifer Kent, Research Fellow, University of Sydney

This article was originally published on The Conversation. Read the original article.

How many people can Australia feed?



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Australia might have been ‘built on the sheep’s back’ but we can’t eat off it.
Stanley Zimny/Flickr, CC BY-NC

Bill Bellotti, The University of Queensland

Population growth has profound impacts on Australian life, and sorting myths from facts can be difficult. This article is part of our series, Is Australia Full?, which aims to help inform a wide-ranging and often emotive debate.


Australia feeds a lot of people. As a big country with a relatively small population, we have just over two arable hectares per person, one of the highest ratios in the world. Our diverse soils and climate provide a wide variety of fresh food all year round.

Historically we produce far more than we consume domestically. We sell around 65% of farm production overseas, making Australia a leading food-exporting nation. We therefore contribute to the food security not just of Australia, but of many other nations.

However, despite being a net food exporter, Australia also imports foods such as coffee, chocolate, processed fruit and vegetables, and key ingredients used in baking our daily bread. We are part of a global food system.

How will a swelling population, projected to reach between 36.8 million and 48.3 million by 2061, affect our food security? Are we set up to weather the storm of climate change, the degradation of our natural resources, and competition for land and water use from mining and urban expansion?

By the numbers

Current Australian government policy is to increase agricultural production and food exports, with a specific focus on developing Australia’s north.

In addition to providing food and nutrition security, the Australian food sector is a key driver of public health, environment, the economy and employment. The gross value of production from Australia’s 135,000 farmers varies between A$55 billion and A$64 billion a year, with exports accounting for between A$45 billion and A$48 billion.

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Horticultural production (fruit, nuts and vegetables) will swell as Australian growers move to satisfy growing Asian demand.

Australian food processing companies add a further A$32 billion of value from 150 large food processors. We exported $A26 billion worth of processed food and beverages in 2015-16 and imported A$16.8 billion, resulting in a trade surplus of A$9.1 billion (rounded to one decimal place).

The food retail sector has an annual turnover around A$126 billion, with about 70% of Australians shopping at Woolworths or Coles. It’s also worth noting that considerable land and water resources are devoted to non-food commodities such as forestry, cotton and wool, and to environmental outcomes such as carbon sequestration or biodiversity plantings.

One in seven Australian jobs (1.6 million) are in the farm-dependent economy, and food and beverage processing employs around one-third of all Australian manufacturing workers, with promising growth prospects. Many jobs are seasonal and based in the regions. Farm and food enterprises rely on foreign workers for many key tasks, resulting in the food sector being particularly sensitive to changes in temporary work visas.

How to feed more people

If Australia reaches its projected population of between 36.8 million and 48.3 million by 2061, could we feed everyone?

For the sake of this exercise, let’s leave aside food we import, and assume that Australia will continue to export 65% of the food we produce.

Currently, our exports feed (at least in part) 36.6 million people outside Australia. If we add that to our domestic population, 61 million people will eat Australian food in 2017.

If we apply the same assumptions to projected high and low Australian populations for 2061, we arrive at a total (domestic plus export) population fed by Australian production of 92 million to 121 million, or an increase of 51-98%.

Could Australia double the number of people we feed by 2061? The answer is yes, but not simply by doubling the amount of food we produce. Three broad strategies will need to be integrated to reach this target:

  1. Increase food productivity. We need to aim for 2% growth in annual food production by increasing investment research and development for food and agriculture. For comparison, between 1949 and 2012 we have averaged 2.1% annual growth, although from 2000-12 that slumped to 0.6%. Achieving this productivity target will be difficult, given the challenge of climate change and other constraining factors.

  2. Reduce food waste. We currently waste around 30% of the food we produce. Reducing food waste benefits the environment and the economy. This strategy requires ongoing improvements in supply chain efficiency, changes in marketing, and consumer education.

  3. Change our eating patterns. Moving towards sustainable diets will improve public health and environment outcomes. Reducing overconsumption (a contributor to obesity), eating more vegetables and less discretionary “junk” foods represent initial steps in this direction.

The next few decades will present unprecedented challenges and opportunities for the Australian food sector. Placing the consumer at the centre of healthy, sustainable and ethical food systems will be increasingly important, whether that consumer lives in Brisbane or Beijing. New ways of connecting consumers to producers will become commonplace, creating more informed and empowered consumers, and rewarding innovation.

Research highlighting the interconnections between food, health and environment will be required to support Australia’s claims to being a clean, green provider of food.

It’s easy to conclude that Australia can feed many more people than we currently do, but the real issue is to do this while ensuring our food system is healthy, sustainable and fair. Ultimately, exporting the research, technology and education that underpin our future food system will benefit far more people than those directly consuming food produced in Australia.


The ConversationYou can read other articles in the Is Australia Full? series here.

Bill Bellotti, Professor and Director Food Systems Program, Global Change Institute, The University of Queensland

This article was originally published on The Conversation. Read the original article.

Get headaches? Here’s five things to eat or avoid



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Drinking more water can help with headaches.
from http://www.shutterstock.com.au

Clare Collins, University of Newcastle

Last week I had a headache. Two hours in a traffic jam, hot day, no water, plans thrown into chaos. That day I was one of the five million Australians affected by headache or migraine. Over a year one person in two will experience a headache.

Mine was a “tension-type” headache, the most common category. Migraines are less common but about one person in eight will experience one in any given year.

Headaches are really common, so here are five things the research evidence indicates are worth trying to help manage or avoid them.

1. Water

A study was conducted in people who got at least two moderately intense or more than five mild headaches a month. The participants received a stress management and sleep quality intervention with or without increasing their water intake by an extra 1.5 litres a day.

The water intervention group got a significant improvement in migraine-specific quality of life scores over the three months, with 47% reporting their headaches were much improved, compared to 25% of the control group.

However, it did not reduce the number or duration of headaches. Drinking more water is worth a try. Take a water bottle everywhere you go and refill it regularly to remind you to drink more water.

2. Caffeine

Caffeine can have opposing effects. It can help relieve some headaches due to analgesic effects but also contribute to them, due to caffeine withdrawal. A review of caffeine withdrawal studies confirmed that getting a headache was the number one symptom of withdrawal, followed by fatigue, reduced energy and alertness, drowsiness, depressed mood, difficulty concentrating, fuzzy head and others.

When people were experimentally put though controlled caffeine withdrawal, 50% got a headache, with withdrawal symptoms occurring within 12-24 hours, peaking between 20-51 hours and lasting from two to nine days. Caffeine withdrawal can happen from a usual daily dose as low as 100 mg/day. One cup of brewed coffee contains 100-150mg caffeine, instant coffee has 50-100 mg depending on how strong you make it and a cup of tea can vary from 10-90mg. It appears that maintaining usual caffeine consumption may subconsciously relate to avoidance of withdrawal symptoms.

Caffeine can lessen or worsen headaches.
Jonathan Thursfiled/Flickr, CC BY

Caffeine can dampen down pain. in a systematic review that included five headache studies with 1,503 participants with migraine or tension-type headache, 33% of participants achieved pain relief of at least 50% of the maximum possible after receiving 100 mg or more caffeine plus analgesic pain medication (ibuprofen or paracetamol) compared to 25% for the analgesic group alone.

A study in over 50,000 Norwegians, who have high caffeine intakes (more than 400 milligrams a day), examined the relationship with headaches. Those with the highest caffeine intakes (more than 540mg/day) were 10% more likely to get headaches, including migraine.

But when headache frequency was examined, high caffeine consumers were more likely to experience non-migraine headaches infrequently (less than seven per month) compared to those considered low caffeine consumers (less than 240mg a day). This was attributed to potential “reverse causation” where high caffeine consumers use caffeine to damp down headache pain. They found those with the lowest caffeine intakes (125mg a day) were more likely to report more than 14 headaches per month, which may have been due to greater sensitivity and avoidance of caffeine.

Hypnic headaches are a rare type that occurs in association with sleep. They typically last 15-180 minutes and are more common in the elderly. Hypnic headaches are treated by giving caffeine in roughly the amount found in a cup of strong coffee.

3. Fasting

Some people get a headache after fasting for about 16 hours, which equates to not eating between 6pm and 10am the next day. A study in Denmark found one person in 25 has been affected by a fasting headache. These headaches are most likely to occur when fasting for a blood test or medical procedure or if you are following a “fasting” weight loss diet or a very low energy meal replacement diet.

Fasting headaches are likely to be confounded by caffeine withdrawal. Check the test procedure instructions to see what fluids, such as tea, coffee and water are allowed and drink within those recommendations.

In a study 34 people with new-onset migraine who kept a headache diary for about a month, those who ate a night-time snack were 40% less likely to experience a headache compared to those who didn’t snack. For susceptible individuals this may prevent fasting headaches. Try a slice or wholegrain toast with a topping like cheese and tomato or avocado and tuna, with a cuppa.

4. Alcohol

Headache is the classic feature of alcohol induced hangovers. The amount of alcohol needed to trigger a hangover varies widely between individuals, from one drink to many. A number of factors mash up to produce a throbbing post alcohol headache. Increased urination and vomiting both increase risk of dehydration which leads to changes in blood and oxygen flowing to the brain.

Congeners, a group of chemicals produced in small amounts during fermentation, give alcoholic drinks their taste, smell and colour. Metabolites of alcohol breakdown in the liver can cross the blood-brain barrier contributing to hangover.

Alcohol can trigger tension-type headaches, cluster headaches and migraine. People with migraines have been shown to have lower alcohol intakes compared to others.
The wise advice is to drink responsibly, boost your water intake and don’t drink on an empty stomach. If you are sensitive to alcohol, avoidance is your best option.

5. Boost your intake of folate-rich foods

More folate in your diet helps migraines.
ahmadpi/flickr, CC BY

Some migraineurs are diet-sensitive. Triggers include cheese, chocolate, alcohol or other specific foods. A recent study found women with low dietary folate intakes had more frequent migraines. However a daily folic acid (1mg) supplement made no difference.

The ConversationBoost your intake of foods rich in folate such as green leafy vegetables, legumes, seeds, chicken, eggs and citrus fruits. Use our Healthy Eating Quiz to check your nutrition, diet quality and variety. Keep a headache diary to identify triggers and then discuss it with your GP.

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

This article was originally published on The Conversation. Read the original article.

Food as medicine: how what you eat shapes the health of your lungs



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Shifting your diet away from processed foods and towards fruits and vegetables can reduce symptoms of asthma.
from www.shutterstock.com

Lisa Wood, University of Newcastle

This article is part of a three-part package “food as medicine”, exploring how food prevents and cures disease. Read other articles in the series here. The Conversation


We all understand that eating too much of the wrong foods – those that are high in energy and low in nutrients, such as fast foods, processed foods and takeaways – causes weight gain and can lead to obesity. These foods are often high in saturated fat, refined carbohydrates (or sugars) and sodium, which increase the risk of developing diabetes, heart disease and some cancers.

But eating poorly has other, somewhat more surprising ramifications. Recently we have come to understand that unhealthy eating patterns can affect our lungs. Switching your diet to one rich in fruit and vegetables could help you breathe easier.

Healthy diets and healthy lungs

Most of the epidemiological evidence linking diet with lung function has focused on chronic obstructive pulmonary disease (COPD). Linked to smoking, COPD causes progressive lung deterioration and asthma.

Several large studies have observed people over time, and found that an unhealthy eating pattern (including refined grains, cured and red meats, desserts and French fries) increases the risk of lung function decline and COPD onset, compared to a healthy eating pattern (including fruit, vegetables, fish and wholegrains).

A recent study followed more than 40,000 men for 13 years, and found a high fruit and vegetable intake was associated with reduced risk of COPD. Current and ex-smokers eating five or more serves a day of fruit and vegetables were 30 to 40% less likely to develop COPD compared to those eating fewer than two serves per day.

A three year study in patients with existing COPD revealed those consuming a high fruit and vegetable diet had an improvement in lung function.

In asthma, there is evidence westernised diets, fast foods and processed foods increase the risk of asthma attacks, lung function decline, wheeze and breathlessness.

We have tested the effect of a high fruit and vegetable diet in asthma sufferers over three months. We found people consuming seven or more servings of fruit and vegetables per day had a reduced risk of asthma attacks, compared to people who consumed a low fruit and vegetable diet (fewer than three servings per day).

Another intervention study in asthma used a diet originally designed to reduce high blood pressure – the Dietary Approaches to Stop Hypertension (DASH) diet – for six months. One of the DASH dietary goals was to consume seven to 12 servings of fruit and vegetables, as well as two to four servings of low-fat/fat-free dairy products, and limiting daily fat and sodium intake. This led to improvements in asthma control and quality of life.

How do fruit and vegetables improve lung health?

People with respiratory diseases such as COPD and asthma typically suffer from inflamed airways. The airway tissue becomes swollen and hypersensitive, excess mucus is produced and the breathing tubes become damaged, sometimes irreversibly. The resulting narrowing of the airways makes it difficult for air to pass in and out of the lungs.

Failure to breathe freely can very quickly become life threatening. Restricted airflow can also have a debilitating effect on day-to-day activities, causing symptoms such as coughing, wheezing, breathlessness and chest tightness in people with asthma and COPD.

Fruit and vegetables are a rich source of several nutrients, in particular soluble fibre and antioxidants, that have been shown to reduce inflammation in the airways.

Dietary fibre reduces lung inflammation

Dietary fibre exists in soluble and insoluble forms. Soluble fibre is fermented by gut bacteria to produce short chain fatty acids. These can bind to specific receptors on the surface of immune cells, which suppress airway inflammation. We have shown a single dose of soluble fibre activates these receptors and reduces inflammation in human airways within just four hours.

Short chain fatty acids can also inhibit expression of the genes that cause airway inflammation, through a process known as epigenetic modification. So a high soluble-fibre intake has the potential to protect against airway inflammation through both activation of anti-inflammatory immune receptors, and inhibition of genes controlling inflammation.

Antioxidants are also anti-inflammatory

Antioxidants present in fruit and vegetables – such as vitamin C, carotenoids and flavonoids – are also beneficial, as they can protect against the damaging effects of free radicals, which are highly reactive molecules produced by activated inflammatory cells that can damage asthmatic airways. Many observational studies have linked antioxidants with lung health.

However, data from antioxidant supplementation trials in asthma are not convincing. Few studies show a beneficial effect, likely due to the use of individual nutrients. Multiple antioxidants exist together in fruit and vegetables, which have interdependent roles that are likely to be critical for their protective effects. So dietary modifications using whole fruit and vegetables is a better strategy.

Sometimes we can become overwhelmed by the nutrition messages in the media, which tell us to eat this and not eat that. Sometimes the advice seems contradictory and confusing. So here is a very simple and focused message for people with respiratory disease – eat more fruit and vegetables!

There’s really nothing to lose and everything to gain. As well as helping to maintain or achieve a healthy weight and reducing the risk of heart disease, diabetes and cancer, you will also be improving your lung health.


Further reading:

Food as medicine: why do we need to eat so many vegetables and what does a serve actually look like?

Food as Medicine: your brain really does want you to eat more veggies

Lisa Wood, Professor, University of Newcastle

This article was originally published on The Conversation. Read the original article.

Food as medicine: your brain really does want you to eat more veggies



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Diet reduces risk of depression through actions on bacteria in the gut, the immune system and the brain.
from www.shutterstock.com

Felice Jacka, Deakin University

This article is part of a three-part package “food as medicine”, exploring how food prevents and cures disease. Read other articles in the series here. The Conversation


As well as our physical health, the quality of our diet matters for our mental and brain health. Observational studies across countries, cultures and age groups show that better-quality diets – those high in vegetables, fruits, other plant foods (such as nuts and legumes), as well as good-quality proteins (such as fish and lean meat) – are consistently associated with reduced depression.

Unhealthy dietary patterns – higher in processed meat, refined grains, sweets and snack foods – are associated with increased depression and often anxiety.

Importantly, these relationships are independent of one another. Lack of nutritious food seems to be a problem even when junk food intake is low, while junk and processed foods seem to be problematic even in those who also eat vegetables, legumes and other nutrient-dense foods. We’ve documented these relationships in adolescents, adults and older adults.

Diet has an impact early in life

The diet-mental health relationship is evident right at the start of life. A study of more than 20,000 mothers and their children showed the children of mothers who ate an unhealthier diet during pregnancy had a higher level of behaviours linked to later mental disorders.

We also saw the children’s diets during the first years of life were associated with these behaviours. This suggests mothers’ diets during pregnancy and early life are both important in influencing the risk for mental health problems in children as they grow.

This is consistent with what we see in animal experiments. Unhealthy diets fed to pregnant animals results in many changes to the brain and behaviour in offspring. This is very important to understand if we want to think about preventing mental disorders in the first place.

Teasing out the cause from the correlation

It’s important to note that, at this stage, most of the existing data in this field come from observational studies, where it is difficult to tease apart cause and effect. Of course, the possibility that mental ill health promoting a change in diet explains the associations, rather than the other way around, is an important one to consider.

What comes first, the junk food or the depression?
from shutterstock.com

Many studies have investigated this and largely ruled it out as the explanation for the associations we see between diet quality and depression. In fact, we published a study suggesting that a past experience of depression was associated with better diets over time.

But the relatively young field of nutritional psychiatry is still lacking data from intervention studies (where study participants are given an intervention that aims to improve their diet in an attempt to affect their mental health). These sorts of studies are important in determining causality and for changing clinical practice.

Our recent trial was the first intervention study to examine the common question of whether diet will improve depression.

We recruited adults with major depressive disorder and randomly assigned them to receive either social support (which is known to be helpful for people with depression), or support from a clinical dietitian, over a three-month period.

The dietary group received information and assistance to improve the quality of their current diets. The focus was on increasing the consumption of vegetables, fruits, wholegrains, legumes, fish, lean red meats, olive oil and nuts, while reducing their consumption of unhealthy “extra” foods, such as sweets, refined cereals, fried food, fast food, processed meats and sugary drinks.

The results of the study showed that participants in the dietary intervention group had a much greater reduction in their depressive symptoms over the three months, compared to those in the social support group.

At the end of the trial, 32% of those in the dietary support group, compared to 8% of those in the social support group, met criteria for remission of major depression.

These results were not explained by changes in physical activity or body weight, but were closely related to the extent of dietary change. Those who adhered more closely to the dietary program experienced the greatest benefit to their depression symptoms.

While this study now needs to be replicated, it provides preliminary evidence that dietary improvement may be a useful strategy for treating depression.

Depression is a whole-body disorder

It’s important to understand researchers now believe depression is not just a brain disorder, but rather a whole-body disorder, with chronic inflammation being an important risk factor. This inflammation is the result of many environmental stressors common in our lives: poor diet, lack of exercise, smoking, overweight and obesity, lack of sleep, lack of vitamin D, as well as stress.

Many of these factors influence gut microbiota (the bacteria and other microorganisms that live in your bowel, also referred to as your “microbiome”), which in turn influence the immune system and – we believe – mood and behaviour.

In fact, gut microbiota affect more than the immune system. New evidence in this field suggests they are important to almost every aspect of health including our metabolism and body weight, and brain function and health. Each of these factors is relevant to depression risk, reinforcing the idea of depression as a whole-body disorder.

What is the human microbiome?

If we do not consume enough nutrient-dense foods such as fruits, vegetables, fish and lean meats, this can lead to insufficiencies in nutrients, antioxidants and fibre. This has a detrimental impact on our immune system, gut microbiota and other aspects of physical and mental health.

Gut microbiota are particularly reliant on an adequate intake of dietary fibre, while the health of the gut may be compromised by added sugars, fats, emulsifiers and artificial sugars found in processed foods.

A diet high in added fats and refined sugars also has a potent negative impact on brain proteins that we know are important in depression: proteins called neurotrophins. These protect the brain against oxidative stress and promote the growth of new brain cells in our hippocampus (a part of the brain critical for learning and memory, and important to mental health). In older adults we have shown that diet quality is related to the size of the hippocampus.

Now we know diet is important to mental and brain health as well as physical health, we need to make healthy eating the easiest, cheapest and most socially acceptable option for people, no matter where they live.


Further reading:

Food as medicine: why do we need to eat so many vegetables and what does a serve actually look like?

Felice Jacka, Principal Research Fellow, Deakin University

This article was originally published on The Conversation. Read the original article.

Food as medicine: why do we need to eat so many vegetables and what does a serve actually look like?


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Why do we need so many serves of vegetables in a day?
Unsplash/Jonathan Pielmayer, CC BY-SA

Genevieve James-Martin, CSIRO; Gemma Williams, CSIRO, and Malcolm Riley, CSIRO

This is the first article in a three-part package “food as medicine”, exploring how food prevents and cures disease. The Conversation


Most Australian adults would know they’re meant to eat two or more serves of fruit and five or more serves of vegetables every day. Whether or not they get there is another question.

A recent national survey reported 45% of Australian women and 56% of Australian men didn’t eat enough fruit. And 90% of women and 96% of men didn’t eat enough vegetables. This figure is worse than for the preceding ten years.

Men had on average 1.6 serves of fruit and 2.3 serves of vegetables per day, and women had 1.8 serves of fruit and 2.5 serves of vegetables. A serve of fresh fruit is a medium piece (about 150 grams) and a serve of vegetables is half a cup of cooked vegetables or about a cup of salad.


The Conversation/Australian Dietary Guidelines, 2013, CC BY-ND

Why do we need so many veggies?

A high intake of fruit and vegetables lowers the risk of type 2 diabetes, heart disease, stroke and some cancers. These chronic diseases are unfortunately common – it’s been estimated A$269 million could have been saved in 2008 if everyone in Australia met fruit and vegetable recommendations.

The recommendation to include plenty of vegetables and fruit in our diet is based on a large body of evidence showing the risk of a range of health conditions is reduced as we eat more fruit and vegetables. The specific targets of two serves for fruit and five to six serves for vegetables are largely based on nutrient requirements for healthy people and what diets usually look like for the average Australian.

So to set these guidelines, certain assumptions are made about dietary practices, such as breakfast being based around cereal/grain and dairy foods, and main meals being comprised of meat and vegetables, usually with a side of something starchy like rice, pasta or the humble potato – an Australian staple.

Does this mean it’s the only pattern to meet all the nutrient requirements? No. Could an adult be equally healthy if they ate three serves of fruit and four serves of vegetables? Yes, probably.

Some recent research even suggests our current targets don’t go far enough. It estimates an optimal intake for reducing our risk of heart disease and early death to be around ten serves of fruit and vegetables a day. Whether we are aiming for two and five, or ten serves, is somewhat academic – the clear message is most of us need to increase our fruit and vegetable intake.

Aussies eat more potatoes than any other veggie.
Agence Producteurs Locaux Damien Kühn/Unsplash, CC BY

Why is two and five such a hard ask?

The populations of most Western countries report eating far less fruit and vegetables than they’re supposed to. So what’s making it so hard for us to get to two and five?

Diets higher in fat, sugar and grains are generally more affordable than the recommended healthy diets high in fruit and veg. In fact, for Australians on low incomes, a healthy food basket for a fortnight would cost 28 to 34% of their income, up to twice the national average for food expenditure.

As a result, people with limited access to food for financial reasons often choose foods with high energy content (because they are filling) over those with high nutritional value but low energy content like fruit and vegetables. These high-energy foods are also easy to over-consume and this may be a contributing factor to weight gain. People who are poorer generally have a diet poorer in quality but not lower in energy content, which contributes to a higher rate of obesity, particularly in women.

Fresh fruit and vegetables cost more to purchase on a dollars per kilojoule basis, and also perish more quickly than processed foods. They take more time and skill to prepare and, after all of that effort, if they don’t get eaten for reasons of personal preference, they go to waste. For many it may not stack up financially to fill the fridge with fruit and vegetables. Under these circumstances, pre-prepared or fast food, which the family is sure to eat without complaint or waste, is all too convenient.

How we can increase veggie intake

The home and school environments are two key influencers of children’s food preferences and intakes. Parents are the “food gatekeepers” and role models particularly for younger children. Where there is parental encouragement, role modelling and family rules, there is an increased fruit and vegetable intake.

Dietary behaviours and food choices often start in childhood and continue through adolescence to adulthood. So encouraging fruit and vegetable intake in schools by mechanisms such as “fruit snack times” may be a good investment.

Policy approaches include subsidies on healthy foods. Other examples include levying a tax on foods of low nutritional value, improved food labelling, and stricter controls on the marketing of unhealthy foods. In Australia debate continues around a tax on sugar-sweetened beverages, which could be used to subsidise healthy foods such as fruit and vegetables.

Research has found the more variety in fruit and vegetables available, the more we’ll consume. Those who meet the vegetable recommendation are more likely to report having at least three vegetable varieties at their evening meal. So increasing the number of different vegetables at the main meal is one simple strategy to increase intake.

This could be made a journey of discovery by adding one new vegetable to the household food supply each week. Buying “in season” fruit and vegetables and supplementing fresh varieties with frozen and canned options can bring down the total cost. Then it’s a matter of exploring simple, quick and tasty ways to prepare them so they become preferred foods for the family.

Genevieve James-Martin, Research Dietitian, CSIRO; Gemma Williams, Research Dietitian, CSIRO, and Malcolm Riley, Nutrition Epidemiologist, CSIRO

This article was originally published on The Conversation. Read the original article.

Tropical Cyclone Debbie has blown a hole in the winter vegetable supply


Ian Sinclair, University of Sydney; Brent Jacobs, University of Technology Sydney; Laura Wynne, University of Technology Sydney, and Rachel Carey, University of Melbourne

Cyclone Debbie, which lashed the Queensland coast a week ago, has hit farmers hard in the area around Bowen – a crucial supplier of vegetables to Sydney, Melbourne and much of eastern Australia. The Conversation

With the Queensland Farmers’ Federation estimating the damage at more than A$100 million and winter crop losses at 20%, the event looks set to affect the cost and availability of fresh food for millions of Australians. Growers are reportedly forecasting a price spike in May, when the damaged crops were scheduled to have arrived on shelves.

The incident also raises broader questions about the resilience of Australia’s fresh vegetable supply, much of which comes from a relatively small number of areas that are under pressure from climate and land use change.

In 2011 the Bowen area produced 33% of Australia’s fresh beans, 46% of capsicum and 23% of fresh tomatoes, making it the country’s largest producer of beans and capsicums, and number two in fresh tomatoes.

The region also produces a significant amount of chillies, corn, cucumbers, eggplant, pumpkin, zucchini and squash, and is a key production area for mangoes and melons.

Coastal Queensland’s vegetable regions are among the highest-producing in the country, especially for perishable vegetables. The Whitsunday region around Bowen, and the area around Bundaberg further south are each responsible for around 13% of the national perishable vegetable supply.

As the chart below shows, vegetable production is highly concentrated in particular regions, typically on the fringes of large cities. These “peri-urban” regions, when added to the two major growing areas in coastal Queensland, account for about 75% of Australia’s perishable vegetables.

Proportion of State Perishable Vegetable Production by weight.
ABS 7121.0 Agricultural Commodities Australia, 2010-11

Australia’s climate variability means that most fresh produce can be grown domestically. The seasonable variability allows production to move from the south to the north in the winter, when the Bundaberg and Bowen areas produce most of the winter vegetables consumed in Brisbane, Sydney and Melbourne. The Bowen Gumlu Growers Association estimates that during the spring growing season in September—October, the region produces 90% of Australia’s fresh tomatoes and 95% of capsicums.

Besides damaging crops, Cyclone Debbie has also destroyed many growers’ packing and cool storage sheds. The cost of rebuilding this infrastructure may be too much for many farmers, and the waterlogged soils are also set to make planting the next crop more difficult.

The recovery of production in these areas is crucial for the supply. Growers who have lost their May crop will first have to wait until the paddocks dry out, then source new seedlings and plant them. It could be weeks until crops can be replanted, and storage and processing facilities replaced.

The Queensland government has announced natural disaster relief funding, including concessional loans of up to A$250,000 and essential working capital loans of up to A$100,000, to help farmers replant and rebuild.

Meanwhile, consumers of fresh vegetables in Sydney and Melbourne and many other places are likely to find themselves paying more until the shortfall can be replaced.

Fresh food for growing cities

Australia’s cities are growing rapidly, along with those of many other countries. The United Nations has predicted that by 2050 about 87% of the world’s population will live in cities. This urban expansion is putting ever more pressure on peri-urban food bowls.

Food production is also under pressure from climate change, raising the risk of future food shocks and price spikes in the wake of disasters such as cyclones. Meanwhile, the desire for semi-rural lifestyles is also conflicting with the use of land for farming (see Sydney’s Food Futures and Foodprint Melbourne for more).

These pressures mean that Australia’s cities need to make their food systems more resilient, so that they can withstand food shocks more easily, and recover more quickly.

Key features of a resilient food system are likely to include:

  • geographic diversity in production, which spreads the risk of crop damage from extreme weather events across a number of different production areas;

  • more local food production, to reduce transportation and storage costs and avoid over-reliance on particular regions;

  • a diverse, healthy and innovative farming community;

  • greater consumer awareness of the importance of seasonal and locally produced food;

  • recycling of urban waste and water for use on farms, to reduce the use of fresh water and fertilisers;

  • the capacity to import food from overseas to meet shortfalls in domestic supply;

  • increased use of protected cropping systems such as greenhouses, which are better able to withstand adverse weather.

Two recent studies of food production around Sydney and Melbourne provide examples of a range of mechanisms and policies for increasing the resilience of the food systems of Australian cities.

Our food system has served us well until now, but land use pressures and climate change will make it harder in future. When a cyclone can knock out a major production region overnight, with knock-on effects for Australian consumers, this points to a lack of resilience in Australia’s fresh vegetable supply.

Ian Sinclair, PhD Candidate. Contested Landscapes – Managing the Tensions between Land Use Planning in Strategic Agricultural Regions on Australia’s Eastern Seaboard., University of Sydney; Brent Jacobs, Research Director, Institute for Sustainable Futures, University of Technology Sydney; Laura Wynne, Senior Research Consultant, Institute for Sustainable Futures, University of Technology Sydney, and Rachel Carey, Research Fellow, University of Melbourne

This article was originally published on The Conversation. Read the original article.