At a time when more and more people are paying attention to their health and nutrition, the demand for food supplements and fortified foods is increasing rapidly. The right balance of vitamins and minerals is crucial for our health. Too little can lead to deficiencies and health problems, but too much is no better. There is a risk of overdose with food supplements in particular, especially when they are high doses and consumed in addition to fortified foods.
This is why the Federal Institute for Risk Assessment (BfR), as a leading institution in the safety assessment of foods and food supplements, is developing proposals for maximum levels to make the consumption of these substances safer. Proposals for maximum levels are therefore essential to protect consumers and enable safe consumption.
The concept of the Tolerable Upper Intake Level (UL) refers to the highest daily intake of a vitamin or mineral at which no harmful health effects are to be expected for the general population. This value is set after a thorough review of the available scientific data on the possible side effects of an overdose. When setting ULs, a distinction is made between water-soluble and fat-soluble vitamins and minerals, as their storage and excretion mechanisms differ.
(Forms of vitamins and minerals and their risks of overdose:)
- vitamins:
- Water-soluble vitamins: This group of vitamins, which includes vitamin C and most B vitamins, is considered safer due to their water-soluble properties and rapid excretion through the kidneys. However, there are exceptions such as vitamin B6, which can have neurotoxic effects when taken in high doses and over a long period of time. Also interesting is the case of vitamin B12, which has been linked in some studies to an increased risk of lung cancer, especially in smokers.
- Fat-soluble vitamins: Vitamins A, D, E and K are stored in the body and can have toxic effects if overdosed. A high intake of vitamin A, for example, can lead to liver damage and other health problems.
Some forms of vitamins, such as the provitamin beta-carotene, which is converted into vitamin A in the body as needed, are less likely to pose overdose risks because the body regulates the conversion rate itself.
- Minerals: Similar to vitamins, minerals can be harmful if taken in excess. For example, too much iron can lead to liver damage and heart problems, while an overdose of selenium can cause neurological damage.
Here are the BfR’s current maximum amount proposals for selected vitamins and minerals in food supplements:
Nutrient |
Notes |
maximum amount (per day) |
Unit |
vitamin A |
|
0.2 |
mg |
beta-carotene |
|
3.5 |
mg |
vitamin D |
|
20 |
µg |
vitamin E |
|
30 |
mg |
vitamin K |
vitamin K1 |
80 |
µg |
vitamin K2 |
25 |
µg |
|
vitamin B1 |
No specific maximum quantities
|
|
- |
vitamin B2 |
No specific maximum quantities |
|
- |
niacin |
nicotinamide |
160 |
mg |
nicotinic acid |
4.0 |
|
|
inositol hexanicotinate |
4.4 |
|
|
vitamin B6 |
|
3.5 |
mg |
folic acid |
|
200
|
µg |
for women of childbearing age and pregnant women in the first trimester to reduce the risk of neural tube defects |
400 |
|
|
vitamin B12 |
|
25 |
µg |
biotin |
No specific maximum quantities
Ingestion can distort laboratory tests |
|
- |
vitamin C |
|
250 |
mg |
potassium |
|
500 |
mg |
calcium |
|
500 |
mg |
iron |
Men, postmenopausal women and pregnant women are only recommended to take iron after consulting a doctor |
6 |
mg |
magnesium |
It is recommended to divide this amount into two or more servings per day |
250
|
mg |
zinc |
|
6.5 |
mg |
iodine |
|
100
|
µg |
Pregnant and breastfeeding women |
150 |
|
|
silicon |
silicon dioxide |
350
|
mg |
silica |
100 |
|
|
choline-stabilized orthosilicic acid |
10 |
|
|
Organic silicon |
10 |
|
|
selenium |
|
45 |
µg |
copper |
Not for children and adolescents |
1 |
mg |
manganese |
|
0.5 |
mg |
chrome |
|
60 |
µg |
molybdenum |
|
80 |
µg |
boron |
Not for children and adolescents |
0.5
|
mg |
To avoid overdoses of vitamins and minerals, various measures are taken:
Consumer education improves awareness of recommended daily intakes and the risks of overdose. However, regulation of dosage on dietary supplement labels can often be inadequate, which may misleadingly appear safe, and specific warnings about overdose are often missing, increasing the risk. In addition, ongoing scientific research and monitoring ensure that recommendations for intake levels are always up to date and minimize potential health risks. Doctors and nutritionists also make an important contribution by offering individualized advice tailored to clients' personal health status and nutritional needs. These combined approaches are critical to promote the safe use of dietary supplements and minimize the risk of overdose.
Conclusion
The maximum levels for food supplements and fortified foods proposed by the Federal Institute for Risk Assessment (BfR) provide important guidelines for the safety and efficacy of these products. These guidelines help to maximize health benefits and reduce the risk of overdose. However, it is crucial to recognize that these recommendations are general suggestions that do not take into account specific differences in gender or body weight. For example, a uniform dosage recommendation might be inappropriate for people of different weights. In addition, individual health conditions and needs can differ significantly from the general recommendations.
It is therefore important for consumers, manufacturers and health professionals to understand these suggestions as basic guidance and to consider them in the context of individual circumstances. Careful adaptation and assessment of recommended intake levels according to personal health status and specific needs is crucial. This will not only promote individual health but also protect the public from the risks that could arise from a blanket application of general guidelines.
Sources:
- Federal Institute for Risk Assessment. "Maximum levels for vitamins and minerals in food supplements and fortified foods." Accessed at: bund.de.
- Federal Institute for Risk Assessment. "Proposed maximum levels for silicon in foods, including food supplements." [PDF]. Accessed at: bund.de.
- Federal Institute for Risk Assessment. "Updated maximum level proposals for vitamins and minerals in food supplements and fortified foods." [PDF]. Accessed at: bund.de.
- Institute of Medicine (US) Subcommittee on Interpretation and Uses of Dietary Reference Intakes; Institute of Medicine (US) Standing Committee on the Scientific Evaluation of Dietary Reference Intakes. "DRI Dietary Reference Intakes: Applications in Dietary Assessment." Washington (DC): National Academies Press (US); 2000. Chapter 6, "Using the Tolerable Upper Intake Level for Nutrient Assessment of Groups." Available from: https://www.ncbi.nlm.nih.gov/books/NBK222879/.
- EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA), Turck, D., et al. (2022). "Guidance for establishing and applying tolerable upper intake levels for vitamins and essential minerals: Draft for internal testing." EFSA Journal, 20(1), e200102. https://doi.org/10.2903/j.efsa.2022.e200102 .
- Fanidi, Anouar et al. “Is high vitamin B12 status a cause of lung cancer?” International journal of cancer vol. 145.6 (2019): 1499-1503. doi:10.1002/ijc.32033