Overview of food supplements

A food supplement is within the EU defined as a concentrated source of nutrients or other substances with a nutritional or physiological effect. There is a wide range of ingredients that might be present in food supplements including, vitamins, minerals, amino acids, essential fatty acids, fiber and various plants and herbal extracts, fungi and spores thereof but also ingredients of animal origin e.g. fish oil. An adequate and varied diet can, under normal circumstances, provide all necessary nutrients in sufficient quantities. However, this ideal situation is not attained by all groups of the population or for all nutrients, particularly those found in a limited number of foods. Since some foods may be excluded from the diet due to intolerance/allergy or because of a particular diet the intake of certain nutrient may be too low. Specific groups in the population may also require food supplements during a limited time of their lives.

As food supplements constitute concentrated sources of nutrients or other ingredients, the risk of consuming substances in amounts that may pose a risk to the health is greater wit food supplements than compared with other foods. In plant based food supplements for instance, it may be difficult to regulate the contents as the chemical composition may vary both within plants and between plants of the same species. Furthermore, there is also a risk of misidentification of species or contamination of unwanted plant material. Some food supplements, such as products intended for weight loss or for enhancing performance have in some instances been shown to contain undeclared substances including pharmaceuticals, designer steroids and CNS (central nervous system) stimulants.

In addition to side effects caused directly by substances in food supplements there is also the possibility of unsafe interactions between pharmacologically active substances and substances in food supplements. Therefore, caution should be exercised when combining prescribed drugs and food supplements and patients are advised to inform physicians about any use of drugs as well as of food supplements.

Link to report

Note: this report is published by the Swedish Food Agency as part of their SLV-Report Series (ISSN: 1104-7089)