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Hypoglycemia in Hereditary Fructose Intolerance

What are the specific reasons for hypoglycemia seen in hereditary fructose intolerance? Hereditary fructose intolerance (HFI) an autosomal recessive disorder in which there is subnormal activity of the enzyme fructose 1-phosphate aldolase B (1;2). Largely found in the liver, the enzyme is needed for normal fructose metabolism for splitting fructose 1-phosphate to form dihydroacetone and glyceraldehyde (1). Hypoglycemia after consumption of fructose (also sucrose or sorbitol) results because of the lack of maintenance of proper blood glucose levels by the liver (2). The fructose ingestion and the lack of aldolase B results in the accummulation of fructose 1-phosphate in cells, particularly in the liver (1). The accumulation leads to depletion of Pi, which in turn keeps mitochondria in hepatocytes from producing ATP causing cell damage, and inhibition of glycogenolysis and, thus, guconeogenesis (1;2). HFI often goes unrecognized and is life-threatening due to hypoglycemia along with poss...

Niacin and Hyperlipidemia

NIACIN FOR HIGH CHOLESTEROL The recommended daily intake for niacin, or vitamin B3, is only 14 mg for women and 16 mg for men with a tolerable upper intake level of 35mg (1). Nutrition professionals should also be aware that niacin, as nicotinic acid (not nicotinamide), has also been used in much larger doses—up to 6 g per day—for decades as a treatment for hyperlipidemia (1). Note that nicotinic acid is available as a dietary supplement. Use as a Drug High-dose niacin, in fact, was the first-ever lipid-modifying drug treatment. It helps increase HDL cholesterol while lowering total serum cholesterol, triglycerides and LDL cholesterol (2). After initial discovery in the 1950s and research in the ‘70s, it was found that niacin helped prevent myocardial infarction and reduced risk of death from myocardial infarction when used in doses of 3 g daily (2;3). The mechanism of high-dose nicotinic acid is broad and unique. It inhibits lipolysis in adipose tissue decreasing free fatty plasma le...