Friedman School of Nutrition Science and Policy, Tufts University
Overt nutritional deficiency diseases, once common worldwide, are extremely rare in developed countries. However, it appears that the prevalence of sub-clinical or marginal deficiencies is higher than expected. Since these deficiencies are major risk factors for chronic diseases such as cancer, cardiovascular diseases and neurodegenerative disorders, the interest of modern nutrition has shifted from preventing overt deficiency to decreasing the risks of chronic diseases.
In the Western medicine, which focuses on treatment of diseases rather than prevention, preventive remedies are mainly nutrients such as vitamins, which are safer and more physiologic than drugs. However, recent clinical trials have failed to demonstrate a beneficial effect of nutritional supplementation on the risk of cardiovascular diseases or cancers and supplementation with high dose synthetic nutrients may even exacerbate the disease processes. In contrast, high dietary intakes of certain nutrients are still effective to reduce the risks of these diseases, clearly emphasizing that the prevention of chronic diseases should be through foods, which are made with nature’s finest ingredients, but not through a pill that contains high dose synthetic nutrients.
Nutrients are not simply food ingredients; they can directly affect the expression of genes that are associated with chronic diseases. Nutrients and bioactive food components delivered by foods interact with genes in our body to maintain our health and prevent chronic diseases. These nutrients also interact with other factors such as exercise and aging. Recently, the most highlighted is nutritional epigenetics, a new mechanism by which nutrients and bioactive food components interact with genetic and environmental factors and alter the expression of critical genes, thereby affecting many physiologic and pathologic processes in our body.
Collectively, the proper intake of foods is the best way to maintain our health and prevent diseases through their interactions with genetic and environmental factors.
(Presented in the International Conference – Thai Food Heritage: Local to Global, 4-6 August 2009, Tawana Bangkok Hotel, Bangkok, organized by The Project of Empowering Network for International Thai Studies (ENITS), Institute of Thai Studies, Chulalongkorn University with support from the Thailand Research Fund (TRF))