Wednesday, 5 January 2022

Four plant-based foods to eat every week

 reprinted from the ABC website


Four plant-based foods to eat every week (and why science suggests they're good for you)

As a laureate professor in nutrition and dietetics people often ask — what do you eat?

Plant-based foods are good sources of healthy nutrients. These include different types of dietary fibre, vitamins, minerals, and a range of phytonutrients, which plants produce to help them grow or protect them from pathogens and pests.

A review of 12 studies with more than 500,000 people who were followed for up to 25 years. It found those who ate the most plant foods were less likely to die from any cause over follow-up time periods that varied across the studies from five to 25 years, compared to those who ate the least.

Here are four versatile and tasty plant foods I have on my weekly grocery list, and the research showing why they're good for you.

1. Tomatoes

Tomatoes are a berry fruit (not a vegetable). They're rich in vitamin C and lycopene, which is a carotenoid. Carotenoids are pigments produced by plants and give vegetables their bright colours.

A review asked people to consume tomato products equivalent to 1 to 1.5 large tomatoes or 1 to 1.5 cups of tomato juice daily for about six weeks.

The researchers found people who did this had reduced blood levels of triglycerides as well as lower total and "bad" cholesterol levels, compared to those who didn't have any tomatoes.

These people also had increased levels of "good cholesterol".

Researchers found consuming any tomato products led to a large decrease in systolic blood pressure (the first number that measures the pressure at which the heart pumps blood).

However, there was no effect on the diastolic pressure (the second number which is the pressure in the heart when it relaxes).

In the group who had high blood pressure to begin with, both systolic and diastolic blood pressure decreased after eating tomato products compared to placebos.

A review included a total of 260,000 men and found those with the highest intakes of cooked tomatoes, tomato sauces and tomato-based foods (equivalent to around one cup per week) had a 15-20 per cent lower risk of developing prostate cancer compared to those with the lowest tomato intakes. Keep in mind correlation doesn't necessarily mean causation, though.

Recipe tips

Keep canned tomatoes in the cupboard and add to pasta sauce, casseroles and soup. Make your own sauce by roasting tomatoes and red capsicum with a splash of olive oil and balsamic vinegar, then puree with a spoon of chilli paste or herbs of your choice. Keep in the fridge.

2. Pumpkin

Pumpkin is rich in beta-carotene, which is also a carotenoid (plant pigment). It gets converted into vitamin A in the body and is used in the production of antibodies. It's also needed to maintain the integrity of cells in eyes, skin, lungs and the gut.

A review looked at associations between what people ate, blood concentrations of beta-carotene and health outcomes.

People who had the highest intakes of foods rich in beta-carotene (such as pumpkin, carrots, sweet potato and leafy greens) had an 8 to 19 per cent lower relative risk of having coronary heart disease, stroke, or dying from any cause in studies over 10 years or more compared to those with the lowest intakes.

3. Mushrooms

Mushrooms are rich in nutrients with strong antioxidant properties.

The body's usual processes create oxidative stresss, which generates "free radicals". These are small particles that damage cells walls and cause the cells to die.

If these aren't neutralised by antioxidants, they can trigger inflammation, contribute to ageing and development of some cancers.

A review found people who ate the most mushrooms had a 34 per cent lower risk of developing any type of cancer compared to those with lowest intakes. For breast cancer, the risk was 35 per cent lower. Though, again, correlation doesn't necessarily mean causation.

Across the studies, a high mushroom intake was equivalent to eating a button mushroom a day (roughly 18 grams).

4. Oats

A review tested the effects on blood sugar and insulin levels from eating intact oat kernels, thick rolled oats or quick rolled oats compared to refined grains.

These found eating intact oat kernels and thick rolled oats led to significant reductions in blood glucose and insulin responses, but not after eating quick rolled oats.

This is likely due to the longer time it takes for your body to digest and absorb the less-processed oats. So it's better to eat whole grain oats, called groats, or rolled oats rather then quick rolled oats.

Oats are a good sources of beta-glucan, a soluble fibre shown to help lower blood cholesterol levels.

Where people were fed a special diet containing about 3.5 grams of oat beta-glucan a day, "bad" cholesterol levels were significantly lower compared with control groups.

Oats showed a small, but important, drop in blood pressure.

Tuesday, 22 September 2020

Why Do We Fry Food in Oil?

 Why Do We Fry Food in Oil?

 

 

Reprinted from ABC Science.  8.3.2019 by John Staughton

 

Everyone has a guilty pleasure when it comes to food, and for many people around the world, particularly certain areas in the United States, there is simply nothing better than fried food to hit that sweet spot of craving. However, as anyone who truly loves this decadent food knows, it isn’t the healthiest choice for life, specifically when it comes to cardiovascular health.

Eating a lot of fried food may be delicious, but it can cause major health issues, which begs the question, is frying food in oil the only way to achieve that crispy deliciousness? Well, the answer to that question isn’t as simple as you may expect. Before we can judge whether there are any alternatives, it is important that we understand why we use oil to fry food in the first place!

Fried Food

Buying a deep-fried Snickers bar at a county fair may seem like a modern phenomenon, capable of being dreamed up only by modern gluttons, but in fact, frying food has been around for at least 2,500 years. Yes, in ancient Greece, people were enjoying the pleasure of fried chicken long before Colonel Sanders ever dreamed up the idea for KFC. This food phenomenon has also been a part of western European culture for more than 700 years, although it was perhaps not as beloved as fried food is today.

The first question that many people ask about fried food is… why use oil in the first place? While oil is certainly more precious than water (and always has been), there are certain characteristics of oil that make it far more viable than water. While water can boil, just like the oil needed for frying, it is difficult to get water above a temperature of 100 Celsius, unless it is exposed to extreme pressures. That temperature simply isn’t high enough to properly “fry” food, so water isn’t really an option. Different vegetable oils, such as flaxseed oil, cottonseed oil and coconut oil, can all be used to fry food effectively, largely due to their chemical composition. Primarily, the boiling and smoke point of oils is significantly higher than water

When food is fried, a few different things happen at the same time. First of all, fried food is usually coated in some sort of barrier, often cornstarch or flour, which will rapidly crisp up when it is exposed to the higher temperatures of frying oil. Between 140 and 160 degrees Celsius, a specific reaction (Maillard Reaction) will occur, which causes the delectable taste and golden-brown appearance of fried food. At the same time, the water inside the food will begin to boil and turn into steam, which can effectively cook the food from the inside out and strengthen the dried crust around the food. The crispy shell will also help to keep some of that steam trapped to more evenly cook the food.

Basically, the short answer to the question of “why do we use oil to fry food” is because it has an ideal chemical composition for the right reactions to occur and produce a delectable dish.

Is There Anything Else We Can Use?

Now that you understand why we use oil to fry food, the next question should be obvious: Given the health risks associated with fried food, and their significantly higher calorie counts, are there any other options for frying food that will be quite as delicious?

Unfortunately, if you want a food to be properly fried, oils and natural fats are the only viable options, but that doesn’t mean that all oils and fats are created equally. Coconut oil is largely considered to be the healthiest oil to cook in, although it can be quite a costly endeavor. Coconut oil is composed primarily of saturated fats, which are very resistant to heat, meaning that the same oil can be used repeatedly without the quality degrading. When choosing any oil to fry your food in, you should pick one with a high ratio of saturated fats to unsaturated fats.

(Image Credit: Flickr)

Aside from coconut oil, many of the oils mentioned above will suffice, including flaxseed oil, rice brain oil, vegetable oil and cottonseed oil. These will vary slightly in terms of cost and flavor, but should produce that golden-brown exterior you are looking for. If you don’t want the flavor of your food to be affected, aim for using an oil with a mild or neutral taste. Olive oil, peanut oil and avocado oil are also excellent alternatives to boring vegetable oil if you want a slightly healthier option, in terms of fat balance.

Vegetable oils are preferred, but animal fats can also work for your frying needs. Ghee, tallow and lard have been used throughout history to fry food, which can produce more of a savory flavor, one that many people appreciate, although this can be even less healthy and add more fat intake to your meal.

Risks of Frying Food in Certain Oils

While you can be somewhat experimental with the oils you use for your deep-frying dreams, there are some oils that should be strictly avoided, as their polyunsaturated fat content is very high. These are often called industrial vegetable oils, and they are less resistant to heat, and more likely to release toxins when used in frying at high temperatures. Some of the oils you should always avoid include safflower oil, grape seed oil, sunflower oil and corn oil.

A Final Word

While fried food is undeniably delicious, it should only be added to your diet on occasion. Cooking food in other ways can be much healthier, and you can better control the amount of calories and fat that your meals contain. That being said, there is nothing better than a piece of delectable fried chicken from time to time, provided you’re using the right oil to fry it.

Wednesday, 13 May 2020

Vitamin D and Calcium: From the ABC


Reprinted from ABC Health and Well being. Posted 29 November 2019,

Vitamin D and calcium are both essential for building healthy bones.

Vitamin D and calcium supplements are often recommended to curb osteoporosis risk
New review finds the vitamins have little value for people who are not vitamin deficient.

Calcium supplements may even cause harm, and have no place in modern medicine, experts say
Now, research has revealed it might be time to ditch two of our most popular vitamins.

Calcium and vitamin D supplements, often recommended to older Australians to prevent osteoporosis, offer very little benefit to healthy adults.

In fact, calcium supplements may be doing more harm than good.

While the nutrients themselves are important, the researchers found calcium and vitamin D supplements did little to reduce fracture risk or improve bone density in the healthy older adult population.

The use of vitamin D as a "general tonic" in individuals who were not vitamin D deficient (or at risk of becoming deficient) was found to be largely fruitless.

"Just as we would not expect antibiotics given to individuals without an active infection to have beneficial effects, we should not expect supplements of calcium and vitamin D to benefit people who do not have demonstrable deficiency," the study authors wrote.

Calcium and vitamin D supplements are often administered together for the prevention and treatment of osteoporosis, which occurs when bones lose minerals, such as calcium, more quickly than the body can replace them.

Previous research into these supplements has produced conflicting results.

But this latest review, which assessed the overall safety and effectiveness of supplements, suggests the supplementation of calcium has little place in modern medicine.

"When you give extra calcium to otherwise healthy people living in the community, it makes no material difference to the number of fractures that occur," lead author Ian Reid, professor of medicine and endocrinology at the University of Auckland.

"And the main reason for giving extra calcium was a belief that that would make bones stronger."

According to the review article, calcium supplements can cause constipation, bloating and kidney stones, and may increase the risk of heart attack.

"Calcium supplements are frequently associated with gastrointestinal symptoms ... and they have also been reported to double the risk of hospital admissions related to abdominal symptoms," the authors wrote.

Vitamin D supplements, on the other hand, rarely cause adverse health outcomes. But there is evidence that very high levels of vitamin D can increase the risk of falls and fractures.

Either way, supplements were found to generally only have value in people with vitamin deficiencies, and not across the healthy older population — so talk to your doctor before starting or stopping any supplements.
Although the evidence for supplements in osteoporosis treatment is not strong, Professor Reid said there are some circumstances where they should still be used.

"Some of the new drugs that we are currently using in osteoporosis have only been assessed when calcium and vitamin D have been given at the same time, so I think we need to proceed cautiously," he said.

The use of calcium and vitamin D supplements in people at risk of vitamin D deficiency who require antiresorptive therapies is appropriate.

"But the most commonly used drugs ... it does not appear to matter. As long as your vitamin D levels are satisfactory, not giving calcium doesn't make any difference to the efficacy of those drugs," Professor Reid said.

Outside of osteoporosis, there are some conditions, such as osteomalacia — a bone disease in which bones soften and weaken — for which calcium and vitamin D supplements are considered appropriate.

Vitamin D supplementation is also advised for frail older people, and in some cases, people who cover their bodies for religious or cultural reasons, who are at risk of vitamin D deficiency.

Our main source of vit D is from the sun, and the best parts of the day to get your sun exposure and vitamin D dose in summer is the mid-morning or mid-afternoon.

For people with fair skin, five to 15 minutes in the sunshine most days a week should do it if your face and arms are exposed.

For people with very fair skin, it's less than that, and for people with darker skin, it can be a little longer.


Tuesday, 25 June 2019

ultra-processed food: copied from the ABC


What is ultra-processed food and how do I avoid it?


They're cheap to produce, designed to last for a long time without spoiling, convenient and engineered to taste delicious.
But ultra-processed foods are increasingly being recognised as unhealthy — even aside from the high salt, fat and sugar content that most of them usually have.
Last month, researchers showed a cause-and-effect relationship between ultra-processed food And weight gain.
A couple of weeks later, two more studies linked these ffods with disease and death.
But what actually is ultra-processed food? And if you want to cut down on it, what should you be looking for?
What is ultra-processed food?
Ultra-processed food is a category in the NOVA food classification system, which is recognised by global health agencies including the UN Food and Agriculture Organisation, and used by many researchers globally.
The system clusters food into four groups based on the amount of processing it has undergone:
1.       Unprocessed and minimally processed foods: Examples include fruit, vegetables, nuts, meat, eggs, milk. Minimal processing may include drying, pasteurisation, cooking or chilling.
2.       Processed culinary ingredients: Examples include oils, butter, sugar and salt. They undergo some processing to make products that can be used in cooking Group 1 foods but they're not meant to be consumed by themselves.
3.       Processed foods: Examples include preserved fruit and vegetables, canned fish, cheese and fresh bread. They're usually made from two or three ingredients.
4.       Ultra-processed foods: These undergo a multitude of processes including many that couldn't be recreated in the home, such as hydrogenation, extrusion, moulding and pre-processing for frying. They contain little, if any, intact Group 1 foods and are industrial formulations that will usually have five or more ingredients, many of which are designed to mimic the qualities of Group 1 foods. Ingredients might include non-sugar sweeteners, hydrolysed proteins, hydrogenated oils and emulsifiers. And they're usually packaged attractively and promoted with intensive marketing.

According to the NOVA system, examples of typical ultra-processed products are:
Sweet or savoury packaged snacks; ice-cream, chocolate, candies (confectionery); mass-produced packaged breads and buns; margarines and spreads; cookies (biscuits), pastries, cakes, and cake mixes; breakfast 'cereals', 'cereal' and 'energy' bars; 'energy' drinks; milk drinks, 'fruit' yoghurts and 'fruit' drinks; cocoa drinks; meat and chicken extracts and 'instant' sauces; infant formulas, follow-on milks, other baby products; 'health' and 'slimming' products such as powdered or 'fortified' meal and dish substitutes; and many ready-to-heat products including pre-prepared pies and pasta and pizza dishes; poultry and fish 'nuggets' and 'sticks', sausages, burgers, hot dogs, and other reconstituted meat products, and powdered and packaged 'instant' soups, noodles and desserts.

More studies are linking ultra-processed foods with disease. Does our focus need to shift?

By having food categories that are globally recognised, researchers can be more precise in measuring the effects of different diets, said Gyorgy Scrinis, a food and nutrition expert from the University of Melbourne.
"We're at the very early stage of knowing exactly what the impacts of the various types of processing techniques and the various ingredients are, but we know this is an area of concern," Dr Scrinis said.
"What this research is telling us is that it's the processing per se, that is part of the problem. It's not just the nutrient profile or the high sugar and salt, for example, or the fats that's necessarily the problem here."
Ultra-processed foods make up a substantial proportion of the Australian diet, he said, probably accounting for close to half of our energy consumption, on average.
How to spot ultra-processed food
While the NOVA system is used by many researchers and international organisations, you're not likely to find it on food packaging in Australia. But if you know what to look for, you can figure out which category a food would fall into.
Reading food labels is the simplest way to spot foods that are ultra-processed — not least because a large proportion of them come in packets.
While not all packaged food is ultra-processed, one of the characteristics of this category of food is that it is designed to have a long shelf life.
Conversely, unprocessed and minimally processed foods often come without any packaging.
On the food label, look at the ingredients list. Would these ingredients be likely to be found in a home kitchen?
"If you see a very long ingredients list with lots of chemical-sounding names, that's probably a good indication it almost definitely is an ultra-processed food."
Ingredients that are generally  only found in ultra-processed foods  include:
·         Some directly extracted from foods, such as casein, lactose, whey, and gluten
·         Some derived from further processing of food constituents, such as hydrogenated or interesterified oils, hydrolysed proteins, soy protein isolate, maltodextrin, invert sugar and high fructose corn syrup
·         Additives such as dyes and other colours, colour stabilisers, flavours, flavour enhancers, non-sugar sweeteners
·         Processing aids such as carbonating, firming, bulking and anti-bulking, de-foaming, anti-caking and glazing agents, emulsifiers, sequestrants and humectants
"The message is to begin to be more aware and also wary of, not just high levels of sugar and salt and fats as we're always being told, but to be very picky about how the foods are being processed and broken down," Dr Scrinis said.
"How has it got to you in this form? What's been done to this food and are there some intact ingredients that we can see there?"
With flavour, low-cost and convenience often appearing in the same brightly coloured package, it's no big surprise that ultra-processed foods form such a large part of our diet.
They're also often marketed as health foods, in the form of meal replacements, diet drinks and breakfast cereals.
Dr Scrinis acknowledged many Australians put ultra-processed food into their shopping trollies because they were "cheap and convenient", but hoped the growing body of research would send a message to governments and food manufacturers that change was needed.
"It's not simply a choice that people make. There are structural issues there in terms of people's affordability and availability of these foods," he said.
"So it's not about cutting them out completely, but it's just being aware how much these foods make up to the totality of our diets."


Friday, 7 June 2019

How much calcium do you need? ABC answers


How much calcium you need per day — plus the top non-dairy sources

By Chloe Warren  (ABC life)                    


You may not know this, but your bones are a bit like a bank.

Except this bank contains almost 99 per cent of your body's calcium.

And like any bank, you want to make sure that you are making more deposits than withdrawals.
Every day your body is withdrawing from your calcium bank (yep, your bones) to ensure your heart, muscles, blood and nerves are healthy and functioning properly.

If your body is not getting enough calcium from your diet to meet its needs, it reacts by 'withdrawing' calcium from your 'bone bank'. Over time these withdrawals will add up (don't they always) and your bone strength will decline, putting you at risk of osteoporosis later in life.

This is all a very long-winded way of saying, calcium is incredibly important and because of this constant turnover, it's important to hit those daily requirements. And there are plenty of ways to get your calcium — even if you're not someone who eats or drinks dairy.

But more than half of the Australian population is not getting enough Calcium.  In particular, it is women who are missing out.

Even though dairy products are recommended as best source of calcium   (as well as protein, potassium, magnesium, phosphorous, zinc and vitamins A, B1, B2 and B12), you can't ignore the fact that many people are ditching dairy in favour of plant-based or lactose-free alternatives.

"It's a mineral that's really essential for our bodies. We all know about calcium and bone health — that includes teeth — but it's also important for other functions, like conducting nerve impulses around the body," explains Aloysa Hourigan, senior nutritionist with Nutrition Australia.

Calcium can be a finicky little dietary requirement, though; just how much you need depends on your age and gender.

Who
Calcium (mg/day)
Serves
Children 1-3 years
500
1-2
Children 4-8 years
700
2
Children 9-11 years
1,000
3
Children 12-18 years
1,300
4+
Adult women 19-50 years
1,000
3
Adult women 51+ years
1,300
4+
Adult men 19-70 years
1,000
3
Adult men 71+ years
1,300
4+
Your calcium intake earlier in life is really about making a deposit into your bone bank.

"Until about the age of 30 you're still laying down bone, and then you're just maintaining what you've got," says Amanda Devine, Professor of Public Health Nutrition at Edith Cowan University.

"Around menopause you tend to lose bone more rapidly — in men, that just happens later. It's really important that throughout life you really try and optimise what bone we've got."

This is especially important when we consider Australia's ageing population.

"Bone breakages after a fall can be devastating for older people. Once you've had a break it can be very hard to get back to that same quality of life as before," explains Professor Devine.

"We are all living longer — women can live a third of their lives in their menopausal years — so we are only going to see this issue even more."

Menopause has a big impact on just how much calcium we need. That's because women experience a huge drop in oestrogen, and that particular hormone is protective for bone health.

So now we know. Calcium is great.

Adults need between 2-4 serves a day of dairy.

"A serve of might be a cup of milk, a couple of slices of cheese, or a pot of yoghurt," says Professor Devine.

Remember, low-fat dairy options have just as much calcium in them as full-fat options.
But what if you don't dig dairy?

Bony fish are a great source — that's things like sardines or salmon.

For vegans and vegetarians, there are plenty of other ways to get your calcium. Eating a hearty mix of leafy greens will do it, and tofu, tahini and calcium-fortified plant milks are good sources as well.

Good sources of calcium — dairy and non-dairy

Good dietary sources of calcium include:
  • Milk and milk products: Milk, yoghurt, cheese and buttermilk. One cup of milk, a 200g tub of yoghurt or 200ml of calcium-fortified soymilk provides around 300mg calcium. Calcium-fortified milks can provide larger amounts of calcium in a smaller volume of milk — ranging from 280mg to 400mg per 200ml milk.
  • Leafy green vegetables: Broccoli, collards (cabbage family), bok choy, Chinese cabbage and spinach. One cup of cooked spinach contains 100mg, although only 5 per cent of this may be absorbed. This is due to the high concentration of oxalate, a compound in spinach that reduces calcium absorption. By contrast, one cup of cooked broccoli contains about 45mg of calcium, but the absorption from broccoli is much higher at around 50-60 per cent.
  • Soy and tofu: Tofu (depending on type; check the label as calcium levels vary) or tempeh and calcium-fortified soy drinks (look for those with at least 120mg of calcium per 100ml).
  • Fish: Sardines and salmon (with bones). Half a cup of canned salmon contains 402mg of calcium.
  • Nuts and seeds: Brazil nuts, almonds and sesame seed paste (tahini). There's about 110mg of calcium in 50g of almonds.
  • Calcium-fortified foods: These include breakfast cereals, fruit juices and bread. One cup of calcium-fortified breakfast cereal (40g) contains up to 200mg of calcium. Half a cup of calcium-fortified orange juice (100ml) contains up to 80mg of calcium, and two slices of bread (30g) provides 200mg of calcium.
Lactose intolerant or vegan then what? 

"Soy beverages would be a way to go. Some of the other rice milks, almond milks and oat milks are good, but soy milk is really the most nutritionally similar to normal milk," explains Professor Devine.
Whatever option you go for as far as alternative milks, it's important to check the label. You want for the beverage to be fortified with calcium, as well as any other key nutrients you might want.

Just make sure to give the carton a shake before pouring it over your cereal or coffee.

"Because of how manufacturers add the nutrients in, some of it can sit in the sediment at the bottom [of the carton]," says Professor Devine.

As with most nutrients, it's generally better to try to work calcium into your diet than to go straight for a supplement. A balanced diet comes with a whole host of advantages that a collection of pills can't really replicate. That being said, if you're really struggling to meet your intake, supplements will do the trick.

Can you have too much calcium?

The jury is still out on this one. There is some evidence that shows too much calcium can contribute to aortic calcification — that's buildup of the mineral on the inner walls of the heart.

Overall, though, the benefits of calcium seem to outweigh the risks, so health guidelines tends to lean towards making sure you get enough of it rather than making sure you don't get too much.

Hopefully by now we can all agree that calcium is fairly important. However, even if you eat the right foods, that's only going to get you part of the way towards optimal bone health.

"If your vitamin D is low, then your ability to absorb calcium is much poorer," Ms Hourigan says.
So get out in the sunshine! But be sensible, please — avoid those peak UV times in the middle of the day. The Australian sun is not kind.

Fairer skinned folk should get around 40 minutes a day during winter, and only around six minutes in summer. People with darker skin can aim for four hours in the winter, and a maximum of 40 minutes in summer.

Of course, no health article can be complete without this little reminder either.
We all need regular exercise.

"Bone density responds to what the body is doing: so if it's sitting down playing computer games all day then that's as good as it's going to get," says Professor Devine.

We should all be incorporating regular exercise into our routines: but that's not news to anyone.

Sunday, 2 June 2019

processed foods kill you: ABC health and wellbeing


Ultra-processed food link to disease and death grows — so do we need to shift our food policy
                           

Just weeks after researchers showed a cause-and-effect relationship between ultra-processed food and weight gain, two more studies have linked these foods with disease and death.

The pair of studies, published in the BMJ today, both looked at consumption of ultra-processed food and health outcomes and — perhaps unsurprisingly — it's not good news.

The first, which was based in France, found increasing the proportion of ultra-processed food in the diet by 10 per cent was associated with significantly higher rates of cardiovascular disease and cerebrovascular disease (such as stroke).

The second, based in Spain, found people who consumed more than four servings of ultra-processed food per day were 62 per cent more likely to die of any cause compared to those who had less than two servings per day.

In both studies, large groups of adults completed food intake questionnaires, then their rates of disease were tracked for up to 10 years.

The findings provide further weight to the already sizeable pile of evidence that highly processed food is linked to poorer health, said Mark Lawrence, who co-wrote an editorial on the topic.

We need to reconsider what it is about these foods that makes them unhealthy, said Professor Lawrence, a food policy expert from Deakin University.

"It's not just about the so-called 'risky' nutrients in foods," he said.

"The nature of the cause is associated with the physical and chemical changes that happen to the food as a result of this high degree of industrial processing.

"It's an independent risk factor irrespective of the presence of, say, sodium or added sugar in the food."

Australian adults get more than a third of their energy from discretionary foods, according to a recent Australian Institute of Health and Welfare report. This definition isn't exactly the same as "ultra-processed" but there is a fair bit of overlap between the two.

What is an 'ultra-processed' food?

If the term "ultra-processed" food conjures images of fluoro-orange cheese-flavoured snacks and sour gummy lollies, you wouldn't be wrong.

But there are other foods you might not realise also fall into this category.

The NOVA food classification system
·         Group 1 - Unprocessed and minimally processed foods: Fruit, vegetables, nuts, meat, eggs, milk. May be dried, pasteurised, cooked or chilled.
·         Group 2 - Processed culinary ingredients: Oils, butter, sugar and salt. Processed to make products that can be used to cook Group 1 food but not meant to be consumed by themselves.
·         Group 3 - Processed foods: Preserved fruit and vegetables, canned fish, cheese and fresh bread. Usually made from two or three ingredients.
·         Group 4 - Ultra-processed foods: Soft drinks, packaged snacks, reconstituted meat, pre-prepared frozen meals. Contain little, if any, intact Group 1 foods. Include ingredients like sweeteners, colours, preservatives and food-derived substances like casein, lactose and gluten.

Packaged biscuits, sausages, instant soups and fruit yoghurts are all classed as ultra-processed under the NOVA food classification system, which is recognised by global health agencies including the UN Food and Agriculture Organisation.

Ultra-processed foods tend to be higher in nutrients we know are not good for us, namely salt, fat and added sugar, but this new wave of evidence suggests their health impact is more than the sum of their parts, said Alexandra Jones from the George Institute for Global Health.

This means a common approach for reformulating packaged foods by simply reducing their salt, fat and sugar content, or fortifying them with fibre and vitamins, might not be enough, Ms Jones said.

"This evidence suggests that perhaps there are some foods that — because they're ultra-processed — it doesn't matter what we do to their nutrient content, it's not going to make them better for us," she said.

"You basically can't make an ultra-processed food healthy by just pumping it full of nutrients.

Current food labelling in Australia focuses on salt, fat and sugar. But both Professor Lawrence and Ms Jones said evidence was mounting to suggest the degree of processing should also be communicated to consumers.

"This has implications across a lot of different areas. I think the front of pack labelling is the most tangible one at the moment," Professor Lawrence said.

"It could be something as simple as, is this an ultra-processed food or not."

Ms Jones said Australia's current labelling systems, which include nutrient breakdowns, ingredients and the opt-in health star ratings were useful and evidence based — but these studies suggested we may need to go further in the future.

"As we watch this evidence evolving, we will be looking at whether we need to review all our nutritional policies to factor in processing as an additional consideration," Ms Jones said.
But that doesn't mean we should ignore information about fats, sugar and salt in a product.

"We shouldn't be scrapping what we already do know well and which is supported by a lot of evidence, which is that there's a lot of risks associated with consumption of foods which are high in salt, sugar and fat, so stay with that advice.

"A lot of these ultra-processed foods are going to be high in these nutrients anyway."