Chronic diseases including heart disease, Type II diabetes, many cancers, some dementias and acute/ chronic gut disorders are a major and growing societal and financial concern. Moreover, an increasingly obese and ageing population means there is greater prevalence of chronic disease. While pharmaceuticals have made an enormous impact on the treatment and prevention of disease during the 20th century, increasingly there is recognition that the next generation health model will comprise both preventative life style and therapeutic entities. Here, food can play a significant role. It is fair to say that in recent times foods have been dominated by stories that are not especially positive – for example the press over transmissible infections, GM foods, BSE, pesticides, preservatives all portray food science and technology in a poor light. However, this is far from the overall truth.
Hippocrates, the father of modern medicine said ‘Let food be thy medicine’ two-and-a-half thousand years ago. This is the basis of the ‘functional foods’ concept whereby dietary ingredients are used for purposes over and above their normal nutritional value. In other words, a functional food is ‘a dietary component that may exert physiological aspects on the consumer which may eventually lead towards justifiable health claims.’ Whilst many of the purported health advantages remain to be determined, it is the case that functional foods have huge commercial and possible biological, significance. The Global Market Review of Functional Foods estimates that by 2013 the worldwide functional food market will reach a value of at least US $90.5bn. Should this potential be realised, then it is important that the approach is underpinned through thoroughly rigorous scientific validity and testing. Should all this come together, then the opportunities for tackling major causes of human morbidity and mortality are enormous.
So, how can a food be more functional than it already is? This may involve one or more of the approaches: fortification through the addition of components seen as desirable such as vitamins or minerals; increasing levels of certain components native to the food, for example enhanced dietary fibre composition; the removal of deleterious compounds such as the extraction, or destruction, of pathogenic bacteria and/or their toxins; and tailoring of the product through replacement of indigenous components including the replacement of fats with emulsified carbohydrates that have a similar technological aspect to the food.
The first generation of functional foods emerged at the end of the 1980’s and largely involved deliberate dietary fortification with organic and inorganic micronutrients. This was rapidly complemented by an explosive increase in the health food market and the current popular use of supplements as part of the daily routine. The concept has now moved heavily towards gastrointestinal function and in particular the impact of gut bacteria. In fact, it is thought that around 60% of the current functional foods market comprises of products that aid digestive health. The biological and clinical importance of resident gastrointestinal microflora in humans is becoming increasingly recognised. Modulation of the human gut microflora towards a more beneficial composition has probiotics and prebiotics as a principal focus. The former are live microorganisms in the diet that are said to improve health, while the latter are specific nutrients for beneficial bacteria indigenous to the gut. These and many other functional food topics are reviewed in the various volumes of the Food Science and Technology Bulletin: Functional Foods published annually by the International Food Information Service.
The emergence of health conscious consumers with a proactive approach of ‘prevention over cure’ and the development of nutritional science has driven the growth of functional foods. The dairy sector currently dominates the functional food market in terms of size and growth. Functional soft drinks are the most successful after dairy, with cereals, drinks and baked products also having major roles.
The changing focus of the food science and industry perspectives towards diet and health means that good research is needed to substantiate health claims. There is also a need for hypothesis driven evidence on the health benefits of food components, so as to understand mechanisms of effect. Today, consumers are more likely to choose functional foods if they have valid explanations of effect.
This issue of Nutraceuticals Now is devoted to the science of functional foods. It has brought together leading authors to review sections that are of much current interest. These include functional food perspectives in various countries, and overviews of major ingredients. It is a timely and first rate collection of the latest functional foods news.
Professor Glenn R. Gibson
Professor of Food Microbial Sciences University of Reading, UK