To the top of the page
Chapter 2.1.4
Module:  2.
Nutritional supplements bioactivity, functional properties and safety: in vitro & in vivo studies
Unit:  2.1.
Nutritional supplements in general
Chapter:  2.1.4.
Do we need nutritional supplements?

Changing culinary and social habits have led to low intakes for some vitamins and minerals compared to those being recommended for certain groups of the population, although the vitamins and minerals and the groups of the population concerned may vary from Member State to Member State. In addition, some argue that optimal health may depend on higher levels of vitamins and minerals than those recommended today on the basis of avoiding deficiencies. Partly due to contemporary lifestyle, people are not following a healthy diet. In Europe, dietary surveys have suggested that there are sub optimal intakes for several micro nutrients. The EU-funded EURRECA 2 project found inadequate intakes for vitamin C, vitamin D, folic acid, calcium, selenium and iodine. A recent comparison of national surveys showed widespread concern about vitamin D intakes, whereas certain age groups are more likely to have low intakes of minerals. For example, there is concern about adequate intakes of iron among teenage girls in Denmark, France, Poland, Germany and the UK. Poor iron status in young women also increases the risk of infants being born with low-birth weight, iron deficiency and delayed brain development. Folate status is also critical for women who may become pregnant. They are advised to take folic acid before conception, and continue for the first 12 weeks of pregnancy. An adequate folate status can decrease the risk of having a baby with neural tube defects such as spina bifida. Recent research suggests that 50-70% of Europeans including habitants of Mediterranean countries have poor vitamin D status, despite their bigger exposure to UV light. In some countries (including UK, Ireland, the Netherlands and Sweden) there are already recommendations for certain groups in the population to take a vitamin D supplement. Other common concerns are shown in Table 2.1.5., although groups considered at risk are not the same in different countries.

Table 2.1.5. Examples of population groups requiring specific advice about supplements
Population group Nutrients
People over age 50 Vitamin D, Vitamin B12, folate
Women of childbearing age Folic acid and vitamin D, possibly iron
Children under age 5 Vitamin A, vitamin C, vitamin D, although children with a good appetite who eat a wide variety of food may not need them.
Breastfeeding individuals Vitamin D
People with insufficient sun exposure or darker skin Vitamin D
Vegans Vitamin B12, vitamin D2

Supplement use varies in Europe. For example, it is common in Germany and Denmark (43% and 59% of the adult population respectively) but is less so in Ireland and Spain (23% and 9% respectively). Women use supplements more than men. Despite having a role in the health of some individuals, not all supplements are useful for everybody. In fact, for some people, it is not advisable to take certain supplements, in particular in high doses. Some studies show multivitamins can contribute to an increased risk of excessive nutrient intakes, and it has been suggested that multivitamins should be formulated with greater consideration for the intakes of micronutrients from foods. The Norwegian dietary recommendations advise people with a very low energy intake (< 6.5 MJ/d or < 1 550 kcal/d) to use a multivitamin/mineral supplement. This applies in particular to elderly persons who have a small food intake. In addition, people of dark complexion and people who are little exposed to sunlight should take a daily supplement of 10 μg of vitamin D in addition to what is ingested through food.

According to a German cohort study the use of vitamin and/or mineral supplements was significantly associated with higher age, being non- or ex-smoker, lower BMI, higher physical leisure time activity, and higher educational level. After adjustment for these factors, there was observed positive associations between supplement use and the consumption of milk, milk products, and fish as well as the intake of vitamin C and beta-carotene. In contrast, the supplement use was related to lower meat and meat product consumption, saturated fat intake, and n6/n3-fatty acid ratio in the diet, both in women and men.

The benefits of nutritional supplements are a source of constant debate. Debates have included whether large doses of vitamins and minerals in the form of nutritional supplements may have undesired health effects. Products in which the content of vitamins and minerals exceeds the maximum values defined by the regulations are classified as pharmaceuticals.

Nutritional supplements contain nutrients that can also be ingested through a healthy diet. According to the regulations, it is illegal to claim or to render the impression that a balanced and varied diet in general will not provide a sufficient supply of vitamins and minerals. The Directorate of Health has defined the recommended intake of various vitamins, minerals and other nutrients. If the diet does not provide these, nutritional supplements can increase the body's level of them, and thereby prevent symptoms of deficiencies. For example, the Norwegian regulations define minimum and maximum limits for the various vitamins and minerals. The maximum limit for vitamin C and vitamin E are 200 mg and 30 mg respectively since Sweden has different regulations, which do not define maximum limits, and therefore their nutritional supplements contain far higher doses of nutrients.

Therefore, food supplements are intended to correct nutritional deficiencies, maintain an adequate intake of certain nutrients, or to support specific physiological functions. Medication use, forces the body to react in certain ways in order to achieve a desirable effect, since nutritional supplement gives the body the actual tools it needs to build health at the cellular level. Nutritional supplements are actually vitamins and minerals that the body needs, to function properly. They are not medicinal products and as such cannot exert a pharmacological, immunological or metabolic action. Therefore, their use is not intended to treat or prevent diseases in humans or to modify physiological functions.

Consequently, it is illegal to claim that nutritional supplements can prevent, heal or alleviate diseases, symptoms of diseases or pain. Such marketing of a nutritional supplement entails its classification as a drug. Dishonest suppliers who market their products with such claims contribute to spreading misconceptions about nutritional supplements. There are also examples of producers who mix undeclared drugs and/or unapproved active substances and herbs into their products.

While these products must comply with a series of European laws, the composition of these products is still largely subject to national legislation, resulting in numerous trade barriers even between European Union (EU) member states. So, while the calls for further regulatory harmonization of food supplements rings loudly, travel along the road to harmonization is slow and difficult.