Used in moderation, alcohol appears to confer some health benefits. The American Heart Association reports that moderate intake of alcohol, 1 or 2 drinks daily, increases HDL cholesterol and reduces your risk of coronary heart disease. However, the adverse effects of excessive use of alcohol are well-documented. Among the risks of alcohol abuse are various nutritional deficiencies, including vitamins, minerals, essential fatty acids and proteins.
Thiamin, Niacin and Pyridoxine
Although alcohol itself is devoid of useful nutrition, it is preferentially processed in your liver by vitamin-dependent enzymes that are also responsible for the metabolism of other compounds, such as carbohydrates and proteins. According to nutritionist Elson Haas, vitamins B-1, B-3 and B-6, or thiamin, niacin and pyridoxine, are directly or indirectly involved in alcohol metabolism, and they are among the first nutrients to be depleted by excessive alcohol consumption.
Riboflavin and B12
Your liver needs glutathione and other antioxidants to detoxify alcohol, and these compounds are not efficiently regenerated in persons who drink too much or too often. A 2011 study published in “Alcoholism, Clinical and Experimental Research” demonstrated that alcohol causes glutathione depletion, which lessens your liver's ability to metabolize alcohol. Since glutathione may also be required for optimal vitamin B-12 function, heavy alcohol use creates a relative B-12 deficiency. Furthermore, an alcohol-damaged liver is less capable of storing vitamin B-12. Finally, vitamin B-2, or riboflavin, is needed to regenerate glutathione, so this vitamin, too, is depleted by alcohol.
Ascorbic Acid and Fat Soluble Vitamins
The nutritional problems associated with alcohol abuse are directly related to the amount of alcohol consumed. Chronic alcohol abuse suppresses your appetite, which leads to poor intake of nutrient-rich foods. A lack of wholesome foods in your diet reduces the availability of the fat-soluble vitamins, A, D, E and K, and nearly all of the B complex vitamins, including thiamin, niacin, folate, vitamin B-6, biotin and vitamin B-12. Ascorbic acid, or vitamin C, is also commonly depleted.
Excessive use of alcohol is associated with serious adverse health consequences, including vitamin deficiencies that involve depletion of B complex vitamins, ascorbic acid and the fat-soluble vitamins. Vitamin replacement therapy, particularly with thiamin, which is directly involved in alcohol and carbohydrate metabolism, is essential for persons who chronically overuse alcohol. Although vitamin supplements are not a substitute for a well-balanced diet, daily supplementation with B vitamins, ascorbic acid and fat-soluble vitamins is worthwhile for people who consume several alcoholic beverages daily. Commercially available vitamin supplements are sufficient for most individuals.