The National Agency for Sanitary, Food, Environmental and Occupational Safety (ANSES) in France said pregnant and breastfeeding women should not consume melatonin in the form of a food supplement.
“Given the variability in the status of melatonin and the regulatory limits governing its use within the European Union, the Agency has questions about the place of melatonin on the market in food supplement form at doses comparable to those of the medicinal product,” ANSES stated.
“In the absence of sufficient data on the safety of daily consumption of 2 milligrams (mg) of melatonin it believes it necessary for a harmonised regulatory framework to be defined at European level on the basis of safety studies conducted for doses below 2 mg.”
90 reported cases
The advice, which also applies to children and adolescents as well as those with inflammatory or autoimmune diseases, epilepsy, asthma, or suffering from mood, behaviour or personality disorders, and anyone treated with medication, comes after 90 reported cases of adverse effects.
General side effects noted include headaches, dizziness, drowsiness, nightmares, irritability and neurological (tremors, migraine) and digestive (nausea, vomiting, abdominal pain) disorders.
ANSES Opinion Request No 2016-SA-0209 further recommends favouring simple formulations that do not combine melatonin with other ingredients and avoiding the concomitant use of several food supplements, in order to limit the risks of interactions.
The agency said each case was analysed individually with conclusions shared amongst parties reporting the cases along with the manufacturers.
They also reminded healthcare professionals to report any adverse effects likely to be associated with the consumption of food supplements to the national nutrivigilance scheme created in 2009 and May 2017.
Melatonin lowdown
Medicinal products, extemporaneous preparations and food supplements use the hormone melatonin, where one of its physiological functions is to promote sleep.
In France, it is available on the market in the form of a medicinal product (Circadin), extemporaneous preparation or food supplement.
In addition to its effects on the biological clock, melatonin has other properties: modulation of mood and the immune system, regulation of body temperature and intestinal function.
It also has vasodilatory, vasoconstrictor and pro-inflammatory activity. Under certain circumstances, or when interacting with other substances, these physiological effects can lead to the occurrence of adverse effects.
The wide variability in the regulatory status of melatonin in the European Union has complicated the regulation of melatonin as the European Food Safety Authority (EFSA) revealed.
In some countries, including Denmark and the Czech Republic, melatonin is prohibited in food supplements.
In Belgium and in Germany, products providing 0.3 mg or more of melatonin per day are considered medicinal products by function, in light of their pharmacological activity.
In Spain and Italy, melatonin is authorised in food supplements up to 1 mg per day.