Balanced diet, not functional food, could improve Dutch health

Functional foods can benefit certain sectors of the population who may not derive the nutrients they need from their daily diet, but they may also pose a risk of overdose of certain vitamins and minerals, according to a new report from The Netherlands.

The report from the Dutch National Institute for Public Health and the Environment reviews food and dietary trends in The Netherlands and their effects on public health, with a view to maximising the impact of government campaigns and research programmes.

The key take-home message is that addressing unhealthy diets would have a major impact on public health. An unhealthy diet (such as insufficient consumption of fish, fruit and vegetables and too many trans and saturated fatty acids) is said to reduce the average life expectancy of Dutch 40 year-olds by 1.2 years, and obesity by 0.8 years.

"Taking into account not just deaths but also years spent living with serious disability, unhealthy dietary habits together cause as much health loss as does smoking," it said.

The report has been praised by Herman Koëter, acting executive director of the European Food Safety Authority, who said it will be "a leading document in Europe and probably beyond when it comes to making risk-benefit analyses of our food and diets". In the chapter dedicated to functional foods and dietary supplements, however, it questions whether these kinds of products can have a health benefit for the general population, or whether some of them may, in fact, may present more of a risk.

"In general, healthy consumers who adhere to the Guidelines of Good Nutrition will have no need for functional foods or health products, the consumption of which will result in little or no health gain for these consumers," wrote the authors.

But they did identify the elderly as being particularly at risk because reduced appetite may lead to insufficient food and nutrient intake; vegans and others whose intake of animal products is low; heavy drinkers who have a less varied eating pattern, and whose intestines may be restricted from absorption of vitamin B1 by alcohol; the elderly and ethnic women who may risk vitamin D deficiency through rarely going outdoors; and those who avoid certain foods due to allergy or adherence to a weight-loss regime.

However, in cases where the health claims behind products have been backed by clinical research, it questions whether the results of such research can really be extrapolated to everyday life.

In a trial situation, dose and usage is carefully controlled, but in an everyday situation consumers may not abide closely by the instructions. Moreover, there are considerable differences in individuals' lifestyles, for example in the amount of exercise they take, which could be measured or controlled in a clinical environment.

The biggest caveat the report gives is that bioactive substances that occur naturally in foods and herbal ingredients that have been used for many years may not be as safe in large doses as they are generally presumed to be.

When several products containing bioactive substances are taken in addition to a normal diet, consumers may ingest higher doses through accumulation, it warns and calls for "systematic research into the toxicity of the substances in questions, whereupon the safe upper limit can be established".

At present, vitamin and mineral-enriched foods marketed in The Netherlands are subject to the Commodities Decree on the Addition of Micronutrients to Foods, and must first be registered with the Food and Consumer Product Safety Authority.

EU legislation to harmonise fortification levels across member states is currently in progress, with a positive vote in Parliament recorded two weeks ago.

It has been several years since a systematic review of functional food and supplement consumption has been carried out across the entire Dutch population (the last survey being in 1997/8, when almost seven per cent of the total Dutch population was reported to consume one or more enriched food product).

The enrichment of products with vitamins and minerals was only authorised in 1996, so it is likely that intake of vitamins and minerals has increase "due to the emergence and burgeoning popularity of functional foods and dietary supplements".

The chapter concludes that it is "extremely important that functional foods and health products are included in future food consumption surveys" , since otherwise it is difficult to assess the health effects at population level.

Overall, healthy eating is said to be a much more pressing issue than food safety, since a poor diet causes about 13,000 deaths due to diabetes, cardiovascular disease and cancer each year, and obesity-related illnesses about 7,000. Foodborne infections, on the other hand, claim between 20 and 200 lives per year.