Pathy's Principles and Practice of Geriatric Medicine. Группа авторов

beverages (e.g. Boost Plus, Ensure Plus) Single Vitamin B12 (cobalamin) Red blood cell formation, neurological function, and DNA synthesis Megaloblastic anaemia, fatigue, weakness, loss of appetite, weight loss, neurological symptoms Impaired intestinal absorption from atrophic gastritis or pernicious anaemia Milk products, meat, fish, poultry, eggs Some cereals MVMs, single, B‐complex After age 50, the chemical form found in supplements or fortified foods is recommended, as it is better absorbed than the protein‐bound food form Folic acid (folate) Coenzyme or cosubstrate in single‐carbon transfers in the synthesis of nucleic acids (DNA and RNA) and metabolism of amino acids Megaloblastic anaemia, weakness, fatigue, difficulty concentrating, irritability, headache, heart palpitations, shortness of breath RDA does not change after age 19 Vegetables (especially dark green leafy vegetables), fruits and fruit juices, nuts, beans, peas, seafood, eggs, milk products, meat, poultry, grains Grains, cereals MVMs, single, B‐complex Folic acid in fortified foods and supplements is better absorbed than food folates Iron In haemoglobin, myoglobin, and numerous enzymes and protein; required for growth, neurological development, and synthesis of some hormones Iron deficiency causes in late stages microcytic anaemia that should be distinguished from microcytic anaemia of chronic disease, exercise RDA decreased for women after age 50; menopausal cessation of menstrual bleeding leads to lower requirement for iron Heme iron in meat, poultry, fish, non‐heme in nuts, beans, vegetables, fortified grain products Grains, cereals Single, MVMs at low levels in products formulated for older adults Heme iron from muscle foods is more bioavailable than non‐heme iron; vegetarians and vegans have higher requirement for iron because of low availability of iron in plant‐based diets Magnesium Cofactor in >300 enzymes, e.g. for protein synthesis, muscle and nerve function, blood glucose control, and blood pressure regulation Numbness, tingling, muscle contractions and cramps, seizures, abnormal heart rhythms, coronary spasms; signs of severe deficiency are hypocalcemia or hypokalemia RDA increases at age 31; intestinal absorption decreases and renal excretion increases with age Yes^{a, b} Many plant and animal foods, e.g. green leafy vegetables, legumes, nuts, seeds, and whole grain Some grains, cereals Some MVMs, single, complex e.g. with ‘bone’ health nutrients In some laxatives, e.g. Phillips’ Milk of Magnesia and some products for indigestion, e.g. Extra‐strength Rolaids Niacin (vitamin B3) Niacin as nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NDP) are coenzymes in oxidation‐reduction reactions Severe deficiency disease is pellagra, with symptoms of dermatitis, diarrhoea, neurologic deficits, including cognitive decline RDA does not change after age 19 Meat, fish, poultry, legumes, whole grains Grains, cereals MVMs, single, B‐complex Dietary tryptophan can be metabolized to niacin; foods rich in tryptophan (e.g. dairy products) can compensate for inadequate dietary niacin Potassium The major intracellular cation, required for normal cellular function Severe deficiency is hypokalemia with cardiac arrhythmias, muscle weakness, glucose intolerance AI does not change after age 19 Yes^a Dark green leafy greens, fruits, vegetables A food additive in some processed foods; typically not added for nutritional benefits Less than 100 mg in over‐the‐counter supplements Amount in supplements is low to help avoid interactions with medications that alter potassium retention or excretion Pyridoxine (vitamin B6) More than 100 enzymes, mainly in metabolism of one‐carbon units, protein, carbohydrates, lipids, neurotransmitters, immune function, haemoglobin, and maintaining normal homocysteine levels Microcytic anaemia, EEC abnormalities, dermatitis, glossitis, depression, confusion, low immunity RDA higher for adults after age 50 Fish, poultry, meat, some beans, fruits and vegetables, especially chickpeas, bananas, and potatoes Grains, cereals MVM, single, B‐complex Riboflavin (vitamin B2) In coenzymes flavin‐mononucleotide (FMN) and flavin‐adenine dinucleotide (FAD) Skin disorders particularly, lips, mouth, throat, degeneration of liver and nervous system RDA does not change after age 19 Yes^b Milk products, eggs, meat, poultry, fish, green vegetables Grains, cereals MVMs, single, B‐complex Selenium Selenoproteins involved in reproduction, thyroid hormone metabolism, DNA synthesis, and protection from oxidative damage and infection Severe deficiency diseases in specific geographical regions (e.g. China, Tibet, Siberia) are Keshan (cardiomyopathy) and Kashin‐Beck (osteoarthritis) RDA does not change after age 19 Yes^b Breads, grains, meat, poultry, fish, and eggs Some meal‐replacement beverages (e.g. Boost Plus, Ensure Plus) MVMs, single Food and/or supplement forms are bioavailable and include selenomethionine, selenium‐enriched yeast, selenite, selenate Thiamin (vitamin B1) Coenzyme for metabolism of carbohydrates and branched‐chain amino acids Severe deficiency is beriberi, which involves peripheral neuropathy and wasting; also Wernicke‐Korsakoff syndrome associated with chronic alcoholism RDA does not change after age 19 Yes^b Meat, fish, poultry, legumes, nuts, seeds Grains, cereals MVM, single, B‐complex Vitamin A Immune function, vision, reproduction, and cellular