What is Doctor’s Best Benfotiamine + Alpha-Lipoic Acid? Benfotiamine (S-benzoylthiamine-O-monophosphate) is a synthetic derivative of thiamin (vitamin B1). Benfotiamine is fat-soluble, more bioavailable, and physiologically active than thiamin. Benfotiamine helps maintain healthy cells in the presence of blood glucose, supports against oxidative stress, and supports healthy aging. Alpha-Lipoic Acid supports the body’s defense against free radicals and recycles antioxidant nutrients such as vitamin C and vitamin E. Alpha-lipoic acid is a sulfur-containing fatty acid, it is soluble in both water and fat and is sometimes referred to as the “universal antioxidant”. How it works? Benfotiamine raises the blood level of thiamin pyrophosphate, the biologically active coenzyme of thiamin, and stimulates transketolase, a cellular enzyme essential for maintenance of normal glucose metabolic pathways. Benfotiamine was shown to cause, on average, a 5-fold greater increase in blood thiamin levels than thiamin mononitrate, with a concomitant greater thiamin concentration in red blood cells. Benfotiamine readily passes through intestinal cells and is converted into thiamin. Alpha-lipoic acid is a key factor in the cellular process that metabolizes glucose for energy production. Aging is accompanied by a decreased ability of the liver to recycle ascorbic acid following oxidative stress. R-lipoic acid, after two weeks of supplementation to aged rats, reversed the age-related impairment of ascorbic acid recycling and concentration in liver cells. Aging is associated with oxidative stress in the brain. The brain’s high rate of metabolism and its long-lived neurons make it particularly vulnerable to oxidative stress. Since alpha-lipoic acid interrupts cellular oxidative processes in both its oxidized and reduced forms, it plays a modulatory role in the brain and nervous system.