Vitamin Intake from Food Supplements in a German Cohort - Is there a Risk of Excessive Intake?

Food supplements, if not properly used, may lead to potentially harmful nutrient intake. The purpose of this survey was to examine vitamin intake from food supplements. Taking into account the intake from food, as obtained from the National Nutrition Survey, it was determined whether the tolerable upper intake levels (ULs) were exceeded via supplements alone, or in combination with food. Data from 1070 supplement users (18 - 93 years) was available. The dietary and supplemental vitamin intakes of three groups were analyzed: average intake (50^th percentile food + 50^th percentile supplements), middle-high intake (50^th + 95^th) and high intake (95^th + 95^th). Vitamin C (53 %), vitamin E (45 %) and B vitamins (37 - 45 %) were consumed most frequently. Few subjects (n = 7) reached or exceeded the ULs through supplements alone. The UL for vitamin A and folate was reached by a few men in the middle-high group, and by a few men and women in the high intake group. Otherwise, even in the high intake group, the recommended vitamin D intake of 20 µg/day (in case of insufficient endogenous synthesis) could not be achieved. The use of food supplements was not associated with excessive vitamin intake in this survey, except in a small number of cases. Vitamin A intake above the UL was the result of high dietary intake which also included the intake of β-carotene, rather than the result of overconsumption of food supplements. Diets mainly included folate from natural sources, which has no associated risk.