KEY POINTS:
Consumers seeking shortcuts to good health are falling prey to aggressive brand advertising for what are known as functional foods.
Some of these foods are promoted as providing health benefits beyond that expected from their nutrients, such as reducing the incidence of cancer or having a cholesterol-lowering effect.
New functional food is promoted almost weekly, says Lincoln University food biochemistry associate professor Dr Geoffrey Savage.
Foods containing added ingredients and claimed to be good for health are increasing in popularity among all age groups.
Dr Savage said functional foods and their promised health benefits were hard to ignore.
"Millions of people are consuming these foods and the people who make functional foods are trading on people's insecurity and looking for an insurance to give them better health."
The term functional food was a curious and confusing concept, he said.
"All foods have a function. We consume them to supply our needs for energy, protein, fats, minerals and vitamins, but functional foods claim to give you that extra bit."
Functional foods were now popular because health-conscious baby boomers had made them the leading trend in the United States food industry, he said.
National Institute for Public Health and the Environment researchers in the Netherlands said 200 new products were launched in Britain in one three-month period.
But the concept was not new, Dr Savage said. "About 52 years ago a small bottle of probiotic drink was introduced to the Japanese market, and since then the functional food industry has grown at an enormous speed.
"There are about 400 new functional foods launched each year in Japan."
The health-giving attributes of foods had been recognised for more than 2500 years but their effectiveness could vary if extracted from food, he said.
"When you extract something from a food and put into a pill, you don't necessarily know it is still active.
"It may be more concentrated but it may not be biologically active and in many cases this is not being tested."
When products were tested the results could prove disappointing and there should be more rigorous and regular testing of functional foods available in pill or other forms.
Original food offered the best and cheapest way to source the functional ingredients, Dr Savage said.
There was evidence foods such as oats, soy, flaxseed, tomatoes, garlic, cabbage-like vegetables, citrus fruits, cranberry, tea and red wine could all deliver impressive health benefits.
The problem was that considerable quantities of these would have to be consumed daily to achieve maximum effect.
Researchers have warned that the medicinal effects of some foods, also known as nutraceuticals or designer foods, could rebound to produce unexpected side-effects.
A British newspaper reported they were banned in some countries because of the risks.
Other researchers have said there is no evidence so far that functional foods cause harm, but the data is limited to five or six years of use.
Duth Institute project director Nynke de Jong wrote in the British Medical Journal that his research on the potential risks of cholesterol-lowering margarines and yoghurts did not augur well for some users of the products.
"These products could trigger reactions in people taking statins - drugs that do the same job but act more powerfully - which might actually increase their risk of heart disease."
Canada had banned the sale of those products, the institute report said.
Dr Savage said cholesterol-lowering margarines were one of the best examples of a functional food with effective health benefits - lowering the risk of heart attacks.
Food products from larger, well-known companies would have undergone testing and monitoring, so tended to be more reliable, he said.
"But it is interesting to note that the majority of the foods being marketed as functional are plant-based.
"There is overwhelming evidence from epidemiological and clinical trials to show that a plant-based diet can reduce the risk of chronic disease, particularly cancer."
- NZPA
Fulfilling a function
The international functional foods market is a $40 billion industry.
Functional foods include:
* Margarines that lower bad cholesterol (LDL).
* Probiotic yoghurts - laced with cultures of bacteria that promote healthy digestion.
* Omega3-enriched muffins, bread and dairy products - for cardiovascular and mental health benefits.
* A2 milk - contains naturally produced a2 beta-casein to help avoid health problems linked with plain milk such as coronary heart disease, childhood diabetes and autism.
* Manuka honey - healing properties, also used as cure for stomach ulcers.
* Herbs and herb-derived products that include echinacea, which studies say can more than halve the risk of catching a cold. More than 800 products containing echinacea are now available.
* Breakfast cereals enriched with vitamins and minerals.
* Kiwifruit extracts - products designed to relieve the symptoms of common digestive complaints such as constipation and heartburn.
* Sports drinks that boost energy.
* Functional foods due to be launched include: Cosmetic yoghurts which claim to "nourish the skin from the inside", soft drinks with added vitamins and minerals, a pasta enriched with grapeseed extract claiming to protect the retina in diabetics and cranberry chewing gum to prevent gum disease.
- NZPA
