Thiamine is essential for metabolizing sugar, and eating too much sugar-laden food and beverages depletes thiamine levels. Symptoms of thiamine deficiency range from neuropathy to beriberi. (Editors of Prevention Magazine. Complete Book of Vitamins: All New Edition. p 1226-127. PA: Rodale Press, 1984.)

Sugar and alcohol, both of which could be considered drugs (at least technically), cause the body to be depleted of “B” vitamins. (Dychtwald, Ken, PhD., ed.Wellness and Health Promotion for the Elderly, p 191. MD: Aspen Publication, 1986.)