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

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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 communication Blindness increases the severity and mortality risk of infections RDA does not change after age 19, although ageing is associated with decreased clearance of vitamin A Yes^b Milk products, fish meat, some fruits and vegetables Milk products, grains, cereals MVMs, single Human diet has preformed vitamin A (retinol and its esterified form, retinyl esters, in animal source foods) and provitamin A carotenoids (beta‐carotene, alpha‐carotene and beta‐cryptoxanthin) Vitamin C (ascorbic acid) Synthesis of collagen, L‐carnitine, some neurotransmitters, protein metabolism, wound healing Severe deficiency known as scurvy RDA does not change after age 19; increased requirement for smokers Yes^a Fruits, vegetables, especially citrus fruits, tomatoes and tomato juice Some fruit drinks, some cereals MVMs, single, antioxidant complex Can be low in canned fruits and vegetables, as well as lost with prolonged cooking Vitamin D Bone mineralization, calcium and phosphorus homeostasis Muscle weakness, poor immune function and bone health (osteomalacia) RDA increased after age 70 in men and women Yes^{a, b} Highest in fatty fish; small amount in meat, cheese, egg yolks Fortified milk products, fluid milk, some yoghurts, some fruit drinks, some orange juice MVMs, single, with calcium Vitamin D3 (cholecalciferol) is preferred form as it is more bioavailable than vitamin D2 (ergocalciferol); high‐dose injections available under medical supervision, but lower daily doses may be preferable¹⁰ Vitamin E Antioxidant, immune function, cell signalling, regulation of gene expression, and other metabolic processes Rare; may occur with fat‐malabsorption with symptoms of peripheral neuropathy, ataxia, skeletal myopathy, retinopathy, poor immunity RDA does not increase after age 19 Yes^a Vegetable oils, nuts, seeds, whole grains, and green leafy vegetables Cereals MVMs, single, antioxidant complex Alpha‐tocopherol is considered the essential form; there are numerous other chemical forms Vitamin K Blood clotting (prothrombin), bone metabolism (osteocalcin) Clinically relevant when prothrombin time is increased AI does not increase after age 19 Green leafy vegetables Boost Plus MVMs at low levels in supplements formulated for older adults Phylloquinone is present primarily in green leafy vegetables and is the main dietary form of vitamin K; menaquinones produced by gut bacteria may satisfy some of the requirement for vitamin K Zinc More than 100 enzymes, protein, immunity, protein synthesis, wound healing, cell division Loss of appetite, impaired immunity, diarrhoea, eye and skin lesions, taste abnormalities RDA does not change after age 19 Meats, poultry, fish, milk products, and eggs Some cereals, grains MVMs, single Zinc is more bioavailable from animal‐sourced foods than from plants

      AI, adequate intake; MVM, multivitamin‐mineral supplement; RDA, recommended dietary allowance; UL, tolerable upper intake level; AI, RDA, and UL are terminology used in the US and Canada.³

      Source: Adapted from NASEM³; US National Institutes of Health, Office of Dietary Supplements⁵; USDA⁶; USDHHS, USDA⁷.

      ^a Considered nutrients of concern because of low intakes in the US.⁷

      ^b Considered nutrients of concern from systematic review and meta‐analysis in community‐dwelling older adults; vitamin D, thiamin, riboflavin, Ca, Mg, and Se.⁸

      Vitamin C is well known for being an antioxidant and is also needed for collagen formation.⁵ The severe vitamin C deficiency disease is known as scurvy, with symptoms of petechiae, ecchymoses, purpura, joint pain, poor wound healing, hyperkeratosis, swollen and bleeding gums, and tooth loss. Vitamin C also promotes iron absorption, especially the inorganic non‐heme forms of iron. Individuals who avoid fruits and vegetables and/or consume only the canned forms of fruits or vegetables are at risk for vitamin C deficiency. Vitamin C is present in most frozen and fresh vegetables but can be lost with prolonged cooking of fruits or vegetables, so steaming as a cooking method and shorter cooking times will optimize preservation of the vitamin.

      Nutrient antioxidants decrease oxidative stress by counteracting the adverse effects of reactive species, e.g. in the human body.¹² Although the most recognized antioxidant nutrients are vitamin C and vitamin E, many nutrients and other food‐derived compounds function as antioxidants.¹² Thus, dietary advice focuses first

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