The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods. Although this approach may involve education, change in nutrition behavior, and discipline, food is the number one source of natural vitamins as they contain many substances such as antioxidants that may contribute to disease risk reduction and health-promoting effects.
Quite a few people in developed countries choose fortified foods, beverages or dietary supplements to help close nutritional gaps and to meet their individual needs. Older people may struggle with eating enough or cooking balanced meals and busy people living today’s fast-paced culture may lack the time to prepare meals or maintain healthy eating habits. Most fortified foods and dietary supplements contain vitamins and other micronutrients, alone or in combination, that have been added in isolated form respectively were made through chemical processes.
There is some discussion as to whether isolated vitamins and those found naturally in whole food are comparable in terms of their effect. As the relationship between nutrition and health is extremely complex and adequate proof-generating methods are lacking, there are presently only theories and no definitive answers (see also Principles).