Influence of lifestyle on vitamin bioavailability

In this review the effects of lifestyle factors, especially alcohol consumption, on vitamin bioavailability are summarized and discussed: Alcohol effects are clearly dose-dependent. Excessive chronic alcohol intake is generally associated with vitamin deficiency (especially folate, thiamine, and vitamin B-6) due to malnutrition, malabsorption, and ethanol toxicity; Effects of moderate alcohol use re mainly explained by a lower vitamin intake. In the case of vitamin A and beta-carotene; effects on post-absorptive (lipoprotein) metabolism have been demonstrated: In one diet-controlled crossover study, alcohol consumption resulted in an increase in the plasma vitamin B-6 (PLP) content, especially after beer consumption (containing vitamin B-6), but also after wine and spirit consumption (not containing vitamin B-6). Smoking is also associated with a lower dietary vitamin intake. In the case of vitamin C, B-12, folate, and beta-carotene, evidence has been presented for effects on postabsorptive metabolism, due to smoke-induced oxidative stress and/or vitamin inactivation: For vitamin E a direct effect of smoking on absorption has been demonstrated. There is no convincing evidence that low-fat diets negatively affect fat-soluble vitamin absorption, :but cholesterol-lowering compounds (diets), or unabsorbable fat substitutes, may do so: Vitamin bioavailability may be compromised from certain vegetables (particularly raw), and/or from high-fiber foods, because of limited digestion and inefficient release of vitamins from the food matrix.