Increased intake of magnesium via supplements can cause diarrhea

19 Dec 2017 --- The increased intake of magnesium via such products as food supplements in addition to the magnesium ingested through a person's normal diet can lead to diarrhea, according to The German Federal Institute for Risk Assessment (BfR)

"Food supplements are in vogue, and many people believe that they can provide health benefits", says President Prof. Dr. Andreas Hensel of BfR. "But the consumption of food supplements may also be associated with health risks. The best nutritional strategy basically involves a balanced and varied diet with plenty of fruit and vegetables. Such a diet supplies a healthy body with all essential substances. In most cases, therefore, food supplements are superfluous."

The aforementioned health problems caused by excessive magnesium intake are fully reversible within one or two days and do not pose a significant health risk to healthy individuals with normal renal function. Nevertheless, these problems are to be viewed as undesirable health effects. Cases of diarrhoea were not observed with intakes of up to 250 mg magnesium per day in addition to the magnesium intake via the normal diet.

The maximum daily level applies to people from the age of 4 upwards. Due to a lack of data, it is not possible to derive a maximum daily level for children below the age of 4. The BfR recommends that the maximum daily dose be divided between at least two intakes per day, as most studies used to derive the maximum level spread the magnesium intake over two or more portions a day, and it is likely that this improves tolerability. In connection with the intake of magnesium via the normal diet, no negative health effects have been observed to date in healthy consumers.

As before, the new assessment of the BfR is based on the current Tolerable Upper Intake Level (UL) derived by the EU's Scientific Committee on Food (SCF), a predecessor body of the European Food Safety Authority (EFSA). In 2001, the SCF derived a UL of 250 mg of magnesium per day for additional (= supplemental) magnesium intake via food supplements or fortified foods. The current assessment by the BfR also incorporates the findings of more recent human studies.

Magnesium is an essential mineral and an element found frequently in the earth's crust as well as in the human body. It plays an important role in many metabolic processes as well as in the formation of nucleic acids, bone formation, membrane physiology, neuromuscular signal transmission and muscle contraction.