Nutrition, Dietetic Products, Novel Food and Allergy
Iron and zink - assessment of suggested maximum limits in food supplements
Report no: 2017: 5 (iron) og 2017: 6 (zinc)
The Norwegian Scientific Committee for Food Safety (VKM) has, at the request of the Norwegian Food Safety Authority (NFSA), evaluated the intake of iron and zink in the Norwegian population.
VKM has also conducted simple scenarios to illustrate the consequences of amending maximum limits for iron and zink in food supplements.
The NFSA will evaluate the national maximum limits for iron and zink in the food supplement regulation.
VKM has made calculations for all age groups aged one year and above.
The existing maximum limit for iron in food supplements is 27 milligram per day. VKM has evaluated the consequences of amending the maximum limit for iron to 5, 10, 20, 30, 40 eller 50 milligram per day.
VKM propose to adopt the tentative tolerable upper intake level of 50 milligram per day for adults and 0.8 milligram per day for children and adolescent set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA).
All of the suggested changes of the maximum limit in food supplements will lead to exceedance of this upper level in 2 and 4 year old children. 9-year-olds can have 5 milligrams per day of iron from supplements, 13-year-olds 20 milligrams per day and adults 30 milligrams per day without exceeding the upper intake levels.
Chronic high intake of iron can lead to diseases
Iron deficiency is one of the most common deficiencies in the world. Iron deficiency can cause fatigue and anemia. Growing children, and women of childbearing age with loss of iron in the blood due to heavy menstruation or pregnancy, have an increased need for iron.
The most common side effects of iron supplements is transient gastrointestinal symptoms. Chronic high intake of iron can lead to iron overload. Iron overload is associated with several severe irreversible adverse health effects such as cancer and cardiovascular diseases. Up to 1 percent of the population is genetically predisposed to iron accumulation in the body that makes them vulnerable to iron overload.
The existing maximum limit for zink in food supplements is 25 milligram per day. VKM has evaluated the consequences of amending the maximum limit for zink to 1, 2, 5, 10 eller 20 milligram per day in Food supplements. VKM propose to adopt the tolerable upper intake level of 40 milligram per day for adults and between 7 and 34 mg milligram per day for children and adolescent set by the Institute of Medicine (IOM), USA.
All of the suggested changes of the maximum limit in food supplements will lead to exceedance of this upper level in 2 and 4 year old children. Nine-year-olds can have 5 milligrams of zinc per day from supplements. 13-year-olds 15 milligrams per day and adults 20 milligrams per day without exceeding the upper intake levels.
Food supplements with zinc can cause nausea and vomiting
Zinc is an important trace element that is neeed for immune function and growth. During pregnancy, infancy, and childhood the body needs zinc to grow and develop properly. Food supplements that contain zinc may cause nausea and vomiting, even at doses close to the recommended intake. Chronically elevated intake of zinc may lead to copper deficiency. Copper deficiency is however very rare due to the abundant amount of copper in the diet.
The VKM Panel on Nutrition, Dietetic Products, Novel Food and Allergy has been responsible for these assessments.