Does eating dairy foods increase your risk of prostate cancer?



If you’re a male who enjoys dairy, there’s no reason to stop having it.
From shutterstock.com

Rosemary Stanton, UNSW

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.


Recent headlines have warned a diet high in dairy foods may increase men’s risk of prostate cancer.

The news is based on a recent review published in the Journal of the American Osteopathic Association which claimed to find eating high quantities of plant-based foods may be associated with a decreased risk of prostate cancer, while eating high quantities of dairy products may be associated with an increased risk.

But if you’re a man, before you forego the enjoyment and known nutritional benefits of milk, cheese and yoghurt, let’s take a closer look at the findings.

What the study did

This study was a review, which means the researchers collated the findings of a number of existing studies to reach their conclusions.

They looked at 47 studies which they claim constitute a comprehensive review of all available data from 2006-2017. These studies examined prostate cancer risk and its association with a wide variety of foods including vegetables, fruits, legumes, grains, meat (red, white and processed), milk, cheese, butter, yoghurt, total diary, calcium (in foods and supplements), eggs, fish and fats.




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Some studies followed groups of men initially free of prostate cancer over time to see if they developed the disease (these are called cohort studies). Others compared health habits of men with and without prostate cancer (called case-control studies). Some studies recorded the incidence of prostate cancer in the group while others concentrated on the progression of the cancer.

For every potential risk factor, the reviewers marked studies as showing no effect, or an increased or decreased risk of prostate cancer. The results varied significantly for all the foods examined.

For cohort studies (considered more reliable than case-control studies), three studies for vegan diets and one for legumes recorded decreased risk of prostate cancer. For vegetarian diets and vegetables, some reported decreased risk and some recorded no effect. Fruits, grains, white meat and fish appeared to have no effect either way.

An increased risk was reported for eggs and processed meats (one study each), red meat (one out of six studies), fats (two out of five), total dairy (seven out of 14), milk (six out of 15), cheese (one out of six), butter (one out of three), calcium (three out of four from diet and two out of three from supplements) and fats (two out of five).

Notably, some very large cohort studies included in the review showed no association for milk or other dairy products. And most case-control studies, though admittedly less reliable, showed no association.

The authors also omitted other studies published within the review period which showed no significant association between dairy and prostate cancer.

A person’s weight likely has more influence on their risk of developing prostate cancer than whether or not they eat dairy.
From shutterstock.com

So the inconsistency in results across the studies reviewed – including large cohort studies – amount to very limited evidence dairy products are linked to prostate cancer.

Could it be vitamin D?

In earlier research, a link between milk and prostate cancer has been attributed to a high calcium intake, possibly changing the production of a particular form of vitamin D within the body.

Vitamin D is an important regulator of cell growth and proliferation, so scientists believed it may lead to prostate cancer cells growing unchecked. But the evidence on this is limited, and the review adds little to this hypothesis.




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Perhaps the review’s most surprising omission is mention of the World Cancer Research Fund (WCRF) Continuous Update Project report on prostate cancer. This rigorous global analysis of the scientific literature identified much stronger risk factors that should be considered as possible confounding factors.

For example, the evidence is rated as “strong” that being overweight or obese, and being tall (separate to weight), are associated with increased risk of prostate cancer. The exact reasons for this are not fully understood but could be especially significant in Australia where 74% of men are overweight or obese.

A new Australian study found a higher body mass index was a risk factor for aggressive prostate cancer.

For dairy products and diets high in calcium, according to the WCRF, the evidence remains “limited”.




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It’s about the whole diet

It’s not wise to judge any diet by a single food group or nutrient. A healthy diet overall should be the goal.

That being said, milk, cheese and yoghurt are included in Australia’s Dietary Guidelines because of evidence linking them with a lower risk of heart disease, type 2 diabetes, bowel cancer and excess weight. These dairy products are also sources of protein, calcium, iodine, several of the B complex vitamins, and zinc.

Evidence about dairy products and prostate cancer remains uncertain. So before fussing about whether to skip milk, cheese and yoghurt, men who wish to reduce their risk of prostate cancer would be better advised to lose any excess weight. – Rosemary Stanton


Blind peer review

I agree with the author of this Research Check who highlights there is a high degree of variability in the results of the studies examined in this review.

While the authors searched three journal databases, most comprehensive reviews search up to eight databases. Further, the authors did not undertake any assessment of the methodological quality of the studies they looked at. So the results should be interpreted with caution.

Although the authors concluded higher amounts of plant foods may be protective against prostate cancer, the figure presented within the paper indicates more studies reported no effect compared to a decreased risk, so how they came to that conclusion in unclear. For total dairy they present a figure showing there were as many studies suggesting no effect or lower risk as there were showing higher risk.

Importantly, they did not conduct any meta-analyses, where data are mathematically pooled to generate and overall effect across all studies.

As the reviewer points out, many other important sources of high quality data have not been included and there are a number of recent higher quality systematic reviews that could be consulted on this topic. – Clare CollinsThe Conversation

Rosemary Stanton, Visiting Fellow, School of Medical Sciences, UNSW

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

Is coconut water good for you? We asked five experts



Nutritionally, coconut water is OK, but it’s healthier to stick to plain water.
from http://www.shutterstock.com

Alexandra Hansen, The Conversation

In recent years coconut water has left the palm-treed shores of tropical islands where tourists on lounge chairs stick straws straight into the fruit, and exploded onto supermarket shelves – helped along by beverage giants such as Coca-Cola and PepsiCo.

Marketed as a natural health drink, brands spout various health claims promoting coconut water. So before we drank the Kool-Aid, we thought we’d check in with the experts whether the nutritional claims stack up. Is coconut water part of a healthy diet or we should just stick to good old water from the tap?

We asked five experts if coconut water is good for you.

Four out of five experts said no

Here are their detailed responses:


If you have a “yes or no” health question you’d like posed to Five Experts, email your suggestion to: alexandra.hansen@theconversation.edu.au


Clare Collins is affiliated with the Priority Research Centre for Physical Activity and Nutrition, the University of Newcastle, NSW. She is an NHMRC Senior Research and Gladys M Brawn Research Fellow. She has received research grants from NHMRC, ARC, Hunter Medical Research Institute, Meat and Livestock Australia, Diabetes Australia, Heart Foundation, Bill and Melinda Gates Foundation, nib foundation, Rijk Zwaan Australia and Greater Charitable Foundation. She has consulted to SHINE Australia, Novo Nordisk, Quality Bakers, the Sax Institute and the ABC. She was a team member conducting systematic reviews to inform the Australian Dietary Guidelines update and the Heart Foundation evidence reviews on meat and dietary patterns. Emma Beckett is a member of the Nutrition Society of Australia, Australian Institute for Food Science and Technology. Her research is funded by the NHMRC and AMP Foundation. She has previously consulted for Kellogg’s. Rebecca Reynolds is a registered nutritionist and the owner of The Real Bok Choy, a nutrition and lifestyle consultancy.The Conversation

Alexandra Hansen, Chief of Staff, The Conversation

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

How Australians talk about tucker is a story that’ll make you want to eat the bum out of an elephant



Wes Mountain/The Conversation, CC BY-ND

Howard Manns, Monash University and Kate Burridge, Monash University

Not to put a damper on things, but Australian food hasn’t always made us happy little Vegemites.

One needn’t look further than the humble meat pie to see how our love/hate relationship with Aussie tucker has evolved. In the early 20th century, the dog’s eye was just a cheap staple on our menus and was peddled by roaming pie-carts.

So low was the lowly meat pie that it became a pejorative term for second-rate boxers, racehorses and bookies. The Australian meat pie western took its place alongside the spaghetti western as a low-quality US cowboy flick not actually filmed in the US (the latter were filmed in Italy).




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But Australians love an underdog, and things began to look up for the meatie from the second world war. When American soldiers arrived, their “Pocket Guide to Australia” noted that meat pies were

the Australian version of the hot dog.

And since at least the 1970s, we’ve had the high mark of patriotism being as Australian as a meat pie.

Of course, modern Australian (mod Oz) cuisine is much more than meat pies and steak and cake (in the words of author Patrick White). So, we thought we’d play babbler (babbling brook “cook”) and cook up a tale of Aussie tucker and its words — a kind of degustation with gobbets of linguistic and culinary history. .

Classy eating, bush tucker and the wallaby trail

From the time of settlement, Australian eating was a story of haves and have nots.

The first Australian cookbook was released in 1864 under the title An Australian Aristologist. The aristologist was the foodie of the 19th century, but the word never took off, pushed out by others like gourmet — French has always given the dining experience a certain je ne sais quoi.

The Australian Aristologist (prominent Tasmanian, Edward Abbott) extolled the virtues of herb gardens, yeast and 30 or so types of bread, but his privilege led him to largely ignore the core staple of many everyday Australians —damper.

This simple, unleavened bread baked in ashes comprised (along with tea and mutton) the bushman’s dinner. It was the linguistic offspring of the original British damper “anything that took the edge off an appetite” with a verbal twist (to damp down “cover a fire with coal or ashes to keep it burning slowly”).

Life could be rough for the bushman and the itinerant worker. Those lucky enough to make tucker (“earn enough to eat”) might tuck in to (“eat”) some banjo (“a shoulder of mutton”), the Old thing (“damper and mutton”) or the bushman’s hot dinner (“damper and mustard”). Those less lucky might be reduced to their billy, a duck’s breakfast (“water”) and the wallaby trail (“the search for food or work”).

The bush diet could be quite muttonous (“sheep-based”), but meat-eating was fraught with gastronomic red herrings (John Ayto’s term). Underground mutton wasn’t mutton, but rather “rabbit”. Colonial goose actually was mutton (“boned leg stuffed with sage & onions”) and so was colonial duck (“boned shoulder with sage and onions”). But Burdekin duck was neither duck nor mutton, but rather “sliced meat fried in batter”. And we reckon seafood fans best steer clear of bush oysters (“testicles”).

Sausage wars and snake’s bum on a biscuit

The Australian food lexicon is often driven by our relationships with one another and the world.

German migration, especially to South Australia, led to the German sausage or the Fritz. However, first world war anti-German sentiment led to attempts to relabel this sausage the Austral. Such renaming efforts were to no avail in South Australia, where Fritz remains Fritz, but were more successful elsewhere.

When the British Royal family changed their surname from Saxe-Coburg-Gotha to Windsor in 1917, Queenslanders followed suit and the German sausage became the Windsor.

Perhaps our most honest assessment of sausages (but also snags, snaggles, snorks, snorkers, starvers, Hitler’s toe in its many varieties) comes from Australian homes and housewives: mystery bags.

Nancy Keesing’s “Lily on the Dustbin” is a treasure trove of such food slang and metaphor among Australian women and families. Keesing highlights heaps of fun ways of expressing hunger:

I could eat a hollow log full of green ants.

I could eat a horse and chase the rider.

I could eat the bum out of an elephant.

I could eat a baby’s bottom through a can chair.

And there are equally fun and cheeky answers for that perennial question, “what’s for dinner?”:

Snake’s bum on a biscuit.

Wait and see pudding.

Standby pudding.

Open the dish and discover the riddle.

Though humorous, Keesing notes that many of these sayings have sombre origins in the Depression era, when dinner really might have been an unfolding mystery from day to day.

Multiculturalism beyond the “culinary cringe”

South Australian Premier Don Dunstan’s 1970s cookbook begins with the following:

For the most part, before the Second World War, our cuisine reflected the decline into which the average English cook of the nineteenth century had sunk. After the war, the influence of migrant groups […] influenced Australian food habits for the better.

The delightfully named (and delightful) Australian food writer Cherry Ripe announced in the 1990s that we were saying goodbye to the culinary cringe – and ours was among the best food in the world.

Our acceptance of multicultural delights have played no small role in this.

For many years, Chinese and Greek pub cooks were relegated to cooking standard Australian fare (such as steak and eggs). But the dim sim/dim sin has long been a bellwether for the culinary delight to come. In fact, American servicemen in Australia during the second world war were informed in their “Pocket Guide to Australia” that the “dim sin” was the Australian replacement for the hamburger.




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But since then, we’ve seen a proliferation of multicultural food items — our cook’s tour has barely scratched the surface. Lots of words are like the cocky on the biscuit tin (“left out”).

We’d love to tell you more about how the chiko roll evolved from observations that chop suey rolls kept falling out of footy fans’ hands. And we’d love to tell you how the lives of the bushmen might have been easier — if they had only taken to the delicacies offered by Australian Indigenous people.

But alas, dear reader, we can but invite you to contribute your favourite food words and stories below!The Conversation

Howard Manns, Lecturer in Linguistics, Monash University and Kate Burridge, Professor of Linguistics, Monash University

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

Are there certain foods you can eat to reduce your risk of Alzheimer’s disease?



Eating healthy foods doesn’t just improve our physical health. It can benefit our mental health, too.
From shutterstock.com

Ralph Martins, Macquarie University

With the rise of fad diets, “superfoods”, and a growing range of dietary supplement choices, it’s sometimes hard to know what to eat.

This can be particularly relevant as we grow older, and are trying to make the best choices to minimise the risk of health problems such as high blood pressure, obesity, type 2 diabetes, and heart (cardiovascular) problems.

We now have evidence these health problems also all affect brain function: they increase nerve degeneration in the brain, leading to a higher risk of Alzheimer’s disease and other brain conditions including vascular dementia and Parkinson’s disease.

We know a healthy diet can protect against conditions like type 2 diabetes, obesity and heart disease. Fortunately, evidence shows that what’s good for the body is generally also good for the brain.




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Oxidative stress

As we age, our metabolism becomes less efficient, and is less able to get rid of compounds generated from what’s called “oxidative stress”.

The body’s normal chemical reactions can sometimes cause chemical damage, or generate side-products known as free radicals – which in turn cause damage to other chemicals in the body.

To neutralise these free radicals, our bodies draw on protective mechanisms, in the form of antioxidants or specific proteins. But as we get older, these systems become less efficient. When your body can no longer neutralise the free radical damage, it’s under oxidative stress.

The toxic compounds generated by oxidative stress steadily build up, slowly damaging the brain and eventually leading to symptoms of Alzheimer’s disease.




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To reduce your risk, you need to reduce oxidative stress and the long-term inflammation it can cause.

Increasing physical activity is important. But here we are focusing on diet, which is our major source of ANTIoxidants.

Foods to add

There are plenty of foods you can include in your diet that will positively influence brain health. These include fresh fruits, seafood, green leafy vegetables, pulses (including beans, lentils and peas), as well as nuts and healthy oils.

Fish

Fish is a good source of complete protein. Importantly, oily fish in particular is rich in omega-3 fatty acids.

Laboratory studies have shown omega-3 fatty acids protect against oxidative stress, and they’ve been found to be lacking in the brains of people with Alzheimer’s disease.

They are essential for memory, learning and cognitive processes, and improve the gut microbiota and function.

Oily fish, like salmon, is high in omega-3 fatty acids, which research shows can benefit our brain health.
From shutterstock.com

Low dietary intake of omega-3 fatty acids, meanwhile, is linked to faster cognitive decline, and the development of preclinical Alzheimer’s disease (changes in the brain that can be seen several years before for onset of symptoms such as memory loss).

Omega-3 fatty acids are generally lacking in western diets, and this has been linked to reduced brain cell health and function.

Fish also provides vitamin D. This is important because a lack of vitamin D has been linked to Alzheimer’s disease, Parkinson’s disease, and vascular dementia (a common form of dementia caused by reduced blood supply to the brain as a result of a series of small strokes).

Berries

Berries are especially high in the antioxidants vitamin C (strawberries), anthocyanins (blueberries, raspberries and blackberries) and resveratrol (blueberries).

In research conducted on mouse brain cells, anthocyanins have been associated with lower toxic Alzheimer’s disease-related protein changes, and reduced signs of oxidative stress and inflammation specifically related to brain cell (neuron) damage. Human studies have shown improvements in brain function and blood flow, and signs of reduced brain inflammation.




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Red and purple sweet potato

Longevity has been associated with a small number of traditional diets, and one of these is the diet of the Okinawan people of Japan. The starchy staple of their diet is the purple sweet potato – rich in anthocyanin antioxidants.

Studies in mice have shown this potato’s anthocyanins protect against the effects of obesity on blood sugar regulation and cognitive function, and can reduce obesity-induced brain inflammation.

Green vegetables and herbs

The traditional Mediterranean diet has also been studied for its links to longevity and lower risk of Alzheimer’s disease.

Green vegetables and herbs feature prominently in this diet. They are rich sources of antioxidants including vitamins A and C, folate, polyphenols such as apigenin, and the carotenoid xanthophylls (especially if raw). A carotenoid is an orange or red pigment commonly found in carrots.

Green vegetables and herbs provide us with several types of antioxidants.
From shutterstock.com

The antioxidants and anti-inflammatory chemicals in the vegetables are believed to be responsible for slowing Alzheimer’s pathology development, the build up of specific proteins which are toxic to brain cells.

Parsley is rich in apigenin, a powerful antioxidant. It readily crosses the barrier between the blood and the brain (unlike many drugs), where it reduces inflammation and oxidative stress, and helps brain tissue recovery after injury.




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Beetroot

Beetroot is a rich source of folate and polyphenol antioxidants, as well as copper and manganese. In particular, beetroot is rich in betalain pigments, which reduce oxidative stress and have anti-inflammatory properties.

Due to its nitrate content, beetroot can also boost the body’s nitric oxide levels. Nitric oxide relaxes blood vessels resulting in lowered blood pressure, a benefit which has been associated with drinking beetroot juice.

A recent review of clinical studies in older adults also indicated clear benefits of nitrate-rich beetroot juice on the health of our hearts and blood vessels.

Foods to reduce

Equally as important as adding good sources of antioxidants to your diet is minimising foods that are unhealthy: some foods contain damaged fats and proteins, which are major sources of oxidative stress and inflammation.

A high intake of “junk foods” including sweets, soft drinks, refined carbohydrates, processed meats and deep fried foods has been linked to obesity, type 2 diabetes and cardiovascular disease.

Where these conditions are are all risk factors for cognitive decline and Alzheimer’s disease, they should be kept to a minimum to reduce health risks and improve longevity.




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The Conversation


Ralph Martins, Professor, Department of Biomedical Sciences, Macquarie University

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

Why is nursing home food so bad? Some spend just $6.08 per person a day – that’s lower than prison



If residents are given poor quality foods that don’t meet their needs or preferences, they’re less likely to eat it.
Shutterstock

Cherie Hugo, Bond University

The Royal Commission into Aged Care Quality and Safety this week turned its attention to food and nutrition. The testimony of maggots in bins and rotting food in refrigerators was horrific.

When so much of a resident’s waking hours is spent either at a meal, or thinking of a meal, the meal can either make or break an elderly person’s day.

So why are some aged care providers still offering residents meals they can’t stomach?

It comes down to three key factors: cost-cutting, aged care funding structures that don’t reward good food and mealtime experiences, and residents not being given a voice. And it has a devastating impact on nutrition.




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How much are we spending on residents’ food?

Our research from 2017 found the average food spend in Australian aged care homes was A$6.08 per resident per day. This is the raw food cost for meals and drinks over breakfast, morning tea, lunch, afternoon tea, dinner and supper.

This A$6.08 is almost one-third of the average for older coupled adults living in the community (A$17.25), and less than the average in Australian prisons (A$8.25 per prisoner per day).

Over the time of the study, food spend reduced by A$0.31 per resident per day.

Meanwhile the expenditure on commercial nutrition supplements increased by A$0.50 per resident per day.

Commercial nutrition supplements may be in the form of a powder or liquid to offer additional nutrients. But they can never replace the value of a good meal and mealtime experience.




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Cutting food budgets, poor staff training and insufficient staff time preparing food on-site inevitably impacts the quality of food provided.

At the royal commission, chefs spoke about using more frozen and processed meals, choosing poorer quality of meats and serving leftover meals in response to budget cuts.

Malnutrition is common, but we can address it

One in two aged care residents are malnourished and this figure has remained largely the same for the last 20 years.

Malnutrition has many causes – many of which are preventable or can be ameliorated. These include:

  • dental issues or ill-fitting dentures
  • dementia (because of difficulty swallowing and sensory sensitivities)
  • a poorly designed dining environment (such as poor acoustics, uncomfortable furniture, inappropriate crockery and table settings)
  • having too few staff members to help residents eat and drink and/or poor staff training
  • not supplying modified cutlery and crockery for those who need extra help
  • not offering residents food they want to eat or offering inadequate food choices.
Residents often need help at mealtimes.
Futurewalk/Shutterstock

My soon-to-be-published research shows disatisfaction with the food service significantly influences how much and what residents eat, and therefore contributes to the risk of malnutrition.

Malnutrition impacts all aspects of care and quality of life. It directly contributes to muscle wasting, reduced strength, heart and lung problems, pressure ulcers, delayed wound healing, increased falls risk and poor response to medications, to name a few.

Food supplements, funding and quality control

Reduced food budgets increase the risk of malnutrition but it’s not the only aged care funding issue related to mealtimes.

Aged care providers are increasingly giving oral nutrition supplements to residents with unplanned weight loss. This is a substandard solution that neglects fundamental aspects of malnutrition and quality of life. For instance, if a resident has lost weight as a result of ill-fitting dentures, offering a supplement will not identify and address the initial cause. And it ends up costing more than improving the quality of food and the residents’ mealtime experience.

Our other soon-to-be-published research shows the benefits of replacing supplements with staff training and offering high-quality food in the right mealtime environment. This approach significantly reduced malnutrition (44% over three months), saved money and improved the overall quality of life of residents.




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However, aged care funding does not reward quality in food, nutrition and mealtime experience. If a provider does well in these areas, they don’t attract more government funding.

It’s not surprising that organisations under financial pressure naturally focus on aspects that attract funding and often in turn, reduce investment in food.

A research team commissioned by the health department has been investigating how best to change aged care funding. So hopefully we’ll see changes in the future.

It’s not just about the food. Residents’ mealtime experiences affect their quality of life.
Ranta Images/Shutterstock

Aged care residents are unlikely to voice their opinions – they either won’t or can’t speak out. Unhappy residents often fear retribution about complaining – often choosing to accept current care despite feeling unhappy with it.




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We lived in an aged care home. This is what we learned

New Aged Care Quality Standards came into effect on July 1 (I was involved in developing the guidelines to help aged care providers meet these standards).

However, they provide limited guidance for organisations to interpret and make meaningful change when it comes to food, nutrition and mealtime experience. Aged care providers will need extra support to make this happen.

We’ve developed an evidence-based solution, designed with the aged care industry, to address key areas currently holding aged care back. The solution offers tools and identified key areas essential for a happier and more nourishing mealtime.

At the end of 2018, our team lived as residents in an aged care home on and off for three months. As a result of this, and earlier work, we developed three key solutions as part of the Lantern Project:

  • a food, nutrition and mealtime experience guide for industry with a feedback mechanism for facilities to improve their performance

  • free monthly meetings for aged care providers and staff to discuss areas affecting food provision

  • an app that gives staff, residents and providers the chance to share their food experiences. This can be everything from residents rating a meal to staff talking about the dining room or menu. For residents, in particular, this allows them to freely share their experience.

We have built, refined and researched these aspects over the past seven years and are ready to roll them out nationally to help all homes improve aged care food, nutrition and mealtime experience.The Conversation

Cherie Hugo, Teaching Fellow, Nutrition & Dietetics, Bond University

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

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



You’re not imagining it. Our bodies really do crave macaroni cheese and other comfort foods as the temperature drops. Here’s why.
from www.shutterstock.com

Megan Lee, Southern Cross University and Jacqui Yoxall, Southern Cross University

It’s winter and many of us find ourselves drawn to bowls of cheesy pasta, oozing puddings, warming soups, and hot chocolate with marshmallows.

These and other comfort foods can make us feel good. But why? And why do we crave them in winter and not in summer?

Research tells us there are three good reasons.




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1. The gut ‘speaks’ to the brain

We know from the relatively new field of nutritional psychiatry that our stomachs produce the “happiness chemicals” dopamine and serotonin. When we eat, a complex process involving the brain means these neurochemicals trigger feelings of happiness and well-being.

These happiness chemicals are also produced when we exercise and are exposed to sunlight, which decline in winter.

This results in a change in the fine balance between the good and bad bacteria that live in our stomachs, and consequently, the relationship between the gut and the brain.

So, in winter when we eat our favourite comfort foods, we get a rush of happiness chemicals sent from the gut to our brain and this make us feel happy and content.




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2. Evolution may have a hand

The second reason we crave more comfort foods during the winter months could be evolutionary. Before we enjoyed technological advances such as housing, heating, supermarkets and clothing, humans who increased their body weight during winter to keep warm were more likely to survive their environmental conditions. Craving carbohydrate and sugar rich foods was therefore a protective mechanism.

Although we are not still living in shelters or foraging for food today, food cravings in winter may still be programmed into our biology.




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3. Psychology, craving and mood

Social learning theory says people learn from each other through observing, imitating and modelling. In the context of food cravings this suggests that what our caregivers gave to us in winter as children has a striking impact on what we choose to eat in winter as adults.

A review of studies on the psychological reasons behind eating comfort food says this food may play a role in alleviating loneliness and boosting positive thoughts of childhood social interaction.

We may also naturally experience lower mood in winter and low mood has been linked to emotional eating.

In winter due to it being darker and colder, we tend to stay indoors longer and self-medicate with foods that are carbohydrate and sugar rich. These types of foods release glucose straight to our brain which gives us an instant feeling of happiness when we are feeling cold, sad, tired or bored.




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Comfort food can be healthy

For all the comfort they provide, comfort foods generally receive a bad rap because they are usually energy and calorie dense; they can be high in sugar, fat and refined carbohydrates.

These types of foods are usually linked to weight gain in winter and if you eat too much over the longer term, can increase the risk of heart disease and diabetes.

However, not all comfort foods are created equally, nor are they all bad for our health.

You still get a comforting feeling with a hearty bowl of soup, but without the extra calories.
from www.shutterstock.com

You can get the same comforting feelings from winter foods containing ingredients that are good for you. For example, a hearty bowl of soup with a slice of wholegrain bread can give you all the components you need for optimal physical and psychological health. Steaming bowls of chilli and curries can provide immunity boosting properties with the use of their warming spices. So too are all the wonderful citrus fruits that become available in the winter.

If you are craving something that is carbohydrate rich, try swapping white varieties for wholegrain versions that will dampen carbohydrate cravings. If you crave a hot chocolate try swapping the cocoa powder for cacao which has a higher concentration of vitamins and minerals.

More good news

The good news for all of us who crave comfort foods in winter is studies that assess intuitive eating — eating when you are hungry, stopping when you are full and listening to what your body is telling you to eat — suggest people who eat this way are happier with their body image, feel better psychologically and are less likely to have disordered eating.

So, embrace this wonderful chilly weather. Rug up in your favourite woolly jumper, sit by the fire, cuddle up with a loved one, make some healthier swaps to your classic comfort foods, remove the food guilt and listen to what your body is telling you it needs during these cold winter months.The Conversation

Megan Lee, Academic Tutor and PhD Candidate, Southern Cross University and Jacqui Yoxall, Senior Lecturer in Allied Health, Southern Cross University

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

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.

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?



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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.

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



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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.