Harrison's Internal Medicine Chapter 71. Vitamin and Trace Mineral Deficiency and Excess Vitamin and Trace Mineral Deficiency and Excess: Introduction Vitamins and trace minerals are required constituents of the human diet since they are either inadequately synthesized or not synthesized in the human body. Only small amounts of these substances are needed for carrying out essential biochemical reactions (., acting as coenzymes or prosthetic groups). Overt vitamin or trace mineral deficiencies are rare in Western countries due to a plentiful, varied, and inexpensive food supply; however, multiple nutrient deficiencies may appear together in persons who are chronically ill or alcoholic | Chapter 071. Vitamin and Trace Mineral Deficiency and Excess Part 1 Harrison s Internal Medicine Chapter 71. Vitamin and Trace Mineral Deficiency and Excess Vitamin and Trace Mineral Deficiency and Excess Introduction Vitamins and trace minerals are required constituents of the human diet since they are either inadequately synthesized or not synthesized in the human body. Only small amounts of these substances are needed for carrying out essential biochemical reactions . acting as coenzymes or prosthetic groups . Overt vitamin or trace mineral deficiencies are rare in Western countries due to a plentiful varied and inexpensive food supply however multiple nutrient deficiencies may appear together in persons who are chronically ill or alcoholic. Moreover subclinical vitamin and trace mineral deficiencies as diagnosed by laboratory testing are quite common in the normal population especially in the geriatric age group. Famine emergency-affected and displaced populations and refugees are at increased risk for protein-energy malnutrition and classic micronutrient deficiencies vitamin A iron iodine as well as for thiamine beriberi riboflavin vitamin C scurvy and niacin pellagra overt deficiencies. Body stores of vitamins and minerals vary tremendously. For example vitamin B12 and vitamin A stores are large and an adult may not become deficient for 1 or more years after being on a depleted diet. However folate and thiamine may become depleted within weeks when eating a deficient diet. Therapeutic modalities can deplete essential nutrients from the body for example hemodialysis removes water-soluble vitamins which must be replaced by supplementation. There are several roles for vitamins and trace minerals in diseases 1 deficiencies of vitamins and minerals may be caused by disease states such as malabsorption 2 both deficiency and excess of vitamins and minerals can cause disease in and of themselves . vitamin A intoxication and liver disease and 3 vitamins and .
