The quality of commonly used food supplements on the Belgian Market.

In Belgium, food supplements are regulated by the Royal Decree of August, 29th, 1997 which was modified April, 4th, 2012 [1,2]. This Decree describes the notification procedure that has to be completed before a market authorization can be obtained next to other criteria that have to be fulfilled such as labeling and advertisements. The third annex of this document is a list of plants allowed to be commercialized as food supplements. For some of these plants maximal daily doses were established by the Advisory Committee for Plant Preparations. In table 1 these limits are shown for Humulus lupulus, Hypericum perforatum, Ginkgo biloba and Glycine max. Each batch of herbal preparations based on these plants should be checked for their compliance to this guideline. The list also proposes suitable methods for these analyses, which should be proven to be applicable to the preparation by the manufacturer. Over the past five years, more than 320 samples of these four herbal preparations were analysed. Only 35% was found to be compliant. There are four main reasons for non-conformity: 12% exceeds the maximal allowed daily dose; 34% did not comply with the limits of content. For over 15% of the samples the content was not specified, consequently compliance of the content could not be determined. Only 1% was found to be adulterated. Additionally we encountered many problems in applying the standard methods to the complex preparations and specific matrices. In conclusion, there is an urgent need for quality control of food supplements by the manufacturer.

Plant	Marker	Maximal daily dose	Number of samples	Number of samples exceeding maximal daily dose	Number of samples non-compliance of content
H. lupulus	8-pregnyl naringenin	400 µg	75	0	16
H. perforatum	Hypericin	700 µg	67	12	32
G. biloba	Flavonolglycosides Terpene lactones	21.6 mg 5.4 mg	96	5	35
G. max	Isoflavones	40 mg	82	20	25

References:

[1] https://portal.health.fgov.be/portal/page?pageid=6,513211&dad=portal&schema=PORTAL.

[2] http://www.health.belgium.be/eportal/foodsafety/foodstuffs/foodsupplements/index.htm#Planten