Older People

By the year 2010, one in five people in the developed world will be aged 65 or over and the needs of an aging population will have a huge impact on society in the next century. Increasing research effort is being directed into ways of helping older people stay healthy, independent and mobile. Lifestyle and environmental factors play a part in some of the most common age-related illnesses including heart disease, osteoporosis, cancer, high blood pressure and chronic infection; which means that people have at least partial control over how well they age. Good nutrition early in life affects longevity and quality of life in later years. Aging changes occur at different rates in different people and it is unclear exactly how these are related to diet and other lifestyle factors. However, there is plenty of scientific evidence to show that good eating habits throughout life can help to promote physical and mental well-being in older people.

 

Diet and Aging

The dietary needs of people in their fifties or sixties are different from those who are younger. For most vitamins and minerals, needs are higher; although for some nutrients they actually fall. The needs of people in their seventies and eighties are different again. Mainstream nutrition is beginning to recognize these differences and some of the new RDAs take into account the needs of those who are older.

Energy intakes and energy expenditure vary widely among elderly people, and are very different in those who are healthy, sick or institutionalized. Older people tend to consume fewer calories than younger people, probably due to loss of muscle, reduced activity levels and lower metabolic rates. As total food intake decreases, individual nutrient intakes also decrease, making it more important to eat nutrient-dense foods and leaving less room for sweets and other empty calorie foods.

Deficiencies of many nutrients are common in elderly people. Normal changes associated with aging, some medications for chronic disease, and relatively common disorders such as diabetes, high blood pressure, constipation and diarrhea can result in higher requirements for some nutrients. Many social and physiological factors such as loneliness, limited income, reduced interest in food, decreased sense of smell and taste, difficulty in chewing or swallowing and reduced vision may also lead to changes in an older person's diet.

New research findings are being published all the time but relatively little is known about how the aging process affects the ability of the body to digest, absorb and retain nutrients. The diets of elderly people are often deficient in several nutrients including vitamins A, C, D, E, B12, thiamin, riboflavin, pyridoxine, niacin, folic acid, calcium, iron, magnesium and zinc. These deficiencies may be due to lower dietary intake, decreased absorption, altered metabolism or increased excretion. They often develop slowly and may mimic the normal changes of aging. Elderly people are particularly at risk of marginal vitamin and mineral deficiencies and early recognition of malnutrition is very important in preventing diseases, maintaining a healthy immune system and increasing lifespan.

 

Digestion

As many as 30 per cent of people aged over 65 develop the inability to produce stomach acid which can lead to reduced absorption of certain vitamins and minerals; including folic acid, calcium, iron and vitamin B12. By the age of 80, as many as 40 per cent of people may be unable to produce stomach acid. Improving digestion can be valuable in improving health in elderly people.

Immunity

Aging is generally associated with a decline of the immune response, which may be linked to a cumulative marginal deficiency of trace minerals and vitamins. Vitamin and mineral deficiencies, particularly of zinc, selenium, and vitamin B6, all of which are prevalent in aged populations, adversely affect immune responses. Because aging and malnutrition exert cumulative influences on immune responses, many elderly people have poor cell-mediated immune responses and are therefore at a high risk of infection. Supplementation with high doses of single nutrients may be useful for improving immune responses of self-sufficient elderly people living at home. Treating nutritional deficiencies in elderly people can reduce the risk of infections and possibly slow the aging process.1

 

Vitamins, Minerals and Older People

Vitamin A

Many older people may consume less than recommended levels of vitamin A, which may lead to poor vision, dry skin, lowered immunity, and may contribute to diseases such as cancer. However, large doses of pre-formed vitamin A could be harmful for elderly people as these may be cleared from the blood and tissues more slowly than in younger people. Vitamin A in the form of beta carotene may be more beneficial.

Creams that contain the vitamin A-derivative, tretinoin, may help to combat premature skin aging. In a 1997 study researchers investigated the activity of enzymes known as metalloproteinases which break down collagen, and found that exposure to ultraviolet light increased the activity of these enzymes. This may lead to premature skin aging. The researchers then found that tretinoin could block the enzyme activity, opening up the possibility that tretinoin may be useful in treating patients with signs of premature skin aging.2

B Vitamins

Low dietary intake of B vitamins is quite common in elderly people and may lead to reduced mental functioning, skin and hair problems, suppressed immunity, depression and other emotional disorders, general weakness, and gastrointestinal problems. Improved nutrition often reverses the symptoms of deficiency, although in some cases permanent damage may occur.

Thiamin

Thiamin deficiency may be relatively common in older people and supplements are likely to be useful in improving quality of life. In a 1997 study, New Zealand researchers measured red blood cell concentrations of a thiamin-dependent enzyme in 222 people aged over 65 years. This measurement was done twice in three months. Thirty-five people who had low levels at both measurement times were divided into two groups. Half were given either a thiamin supplement of 10 mg per day and half were given a placebo for three months. The researchers then assessed blood pressure, body weight, height, body mass index, hand grip strength and cognitive function in the subjects. The results showed that the supplements decreased blood pressure and weight. Those taking the supplements reported improved quality of life, sleep and energy levels.3

Vitamin B6

Vitamin B6 requirements increase considerably in elderly people, possibly due to reduced absorption. Low vitamin B6 levels may also lead to increased risk of several disorders, including heart disease. In a study published in 1996 Dutch researchers studied the vitamin B6 intake and blood levels in 546 elderly Europeans, aged from 74 to 76, with no known vitamin B6 supplement use. They also examined links with other dietary and lifestyle factors, including indicators of physical health. The results showed that 27 per cent of the men and 42 per cent of the women had dietary vitamin B6 intakes below the mean minimum requirements. Twenty-two per cent of both men and women had low blood levels.4 The neurological and immunological effects of deficiency are usually reversible with supplementation.

Folate

Many elderly people do not consume enough folate in their diets. In a 1996 Canadian study, researchers investigated folate and vitamin B12 intakes and body levels in 28 men and 30 women aged over 65 years. The results showed that 57 per cent of men and 67 per cent of women were at risk of deficiency.5 One of the most common disorders in elderly people is cardiovascular disease. There is increasing evidence that folic acid deficiency plays a role in the development of this disease through an increase in homocysteine levels. Supplements may be useful for their protective effects.

Folate deficiency may also cause or worsen the mental difficulties often experienced by older people. In a study done in 1996 in Spain, researchers analyzed the relationship between mental and functional capacities and folate status in a group of 177 elderly people. In this study, almost 50 per cent of the people had folate intakes below recommended values. Those with poor test results had significantly lower folate levels.6

Vitamin B12

Inadequate vitamin B12 intake is relatively common in elderly people, with 10 to 20 per cent of elderly people having some level of vitamin B12 deficiency. This can result in reduced mental capacity and other neurological disorders that can resemble Alzheimer's disease. Older people often have a reduced capacity to absorb vitamin B12 due to low stomach acid and lack of intrinsic factor, the compound necessary for absorption. A stomach disorder known as atrophic gastritis may also limit absorption. Some experts believe that the incidence of pernicious anemia resulting from low vitamin B12 levels may be more common than previously thought, with up to 800,000 elderly people in the US suffering from the disease.

Low vitamin B12 levels in older people may also reduce the effectiveness of the immune response. Recent research has shown that elderly people with low vitamin B12 levels may have impaired antibody responses to vaccination even though their immune systems are apparently functioning adequately.7

Supplementation can prevent irreversible neurological damage if started early. Elderly people with vitamin B12 deficiency may show psychiatric or metabolic deficiency symptoms even before anemia is diagnosed. Screening for low vitamin B12 levels is necessary in elderly people with mental impairment, although it has also been found that deficiency states can still exist even when blood levels are higher than the traditional lower reference limit for vitamin B12. Patients who are most at risk of vitamin B12 deficiency include those with gastrointestinal disorders, autoimmune disorders, Type I diabetes mellitus and thyroid disorders, and those receiving long-term therapy with gastric acid inhibitors.8

Other B Vitamins

Mild riboflavin deficiency may be quite common in elderly people whose diets are low in red meat and dairy products. Niacin deficiency is also relatively common.

Vitamin D

Vitamin D absorption from food may decrease with age. Elderly people often also get less exposure to the sun and have a reduced capacity for skin synthesis, a major source of vitamin D. This may increase the risk or worsen the symptoms of osteoporosis, cancer, diabetes and arthritis.

Studies show that elderly people, particularly those who are housebound or in institutions, may be at high risk of vitamin D deficiency. Older people who frequently use sunscreens may also be more likely to suffer from vitamin D deficiency. A study published in 1998 in the New England Journal of Medicine found vitamin D deficiency in 57 per cent of a group of 290 patients who were admitted to hospital. In a subgroup of the patients who had no known risk factors for vitamin D deficiency, the researchers found that 42 per cent were deficient. They concluded that vitamin D deficiency was probably a substantial problem.9

In recognition of the increased vitamin D needs of older people, the RDAs have been raised. For adults under 50, the RDA is 200 IU; while for those over 50, it is now 400 IU; and for those over 70, it is 600 IU.

 

Osteoarthrtitis

Osteoarthritis sufferers who have low vitamin D intakes seem to suffer more severe symptoms than those whose intakes are high. In a study done in 1996, researchers at Boston University studied more than 500 elderly people with osteoarthritis of the knee. They found that those with the lowest intakes and blood levels of vitamin D were three times more likely to see their disease progress than people with high intakes and blood levels. Vitamin D may help reduce the cartilage damage seen in osteoarthritis.10

 

Osteoporosis

Vitamin D deficiency increases the risk of osteoporosis in elderly men and women and supplements may be useful in reducing bone loss and the occurrence of fractures. In a study published in 1997, researchers at Tufts University in Boston assessed the effects of calcium (500 mg per day) and vitamin D (700 IU per day) in 176 men and 213 women aged 65 years or older. When bone density was measured after a three-year period, those taking the supplements had higher bone density at all body sites measured. The fracture rate was also reduced by 50 per cent in those taking the supplements.11 However, other studies have not shown any reduction in fracture rates in those taking vitamin D supplements.12 Vitamin D supplements may also be useful in preventing bone loss in patients taking corticosteroid drugs.13

 

Antioxidants

Research suggests that the antioxidants beta carotene, vitamin C, vitamin E and selenium may help to prevent aging-related diseases such as cardiovascular disease, cancer, cataracts, rheumatoid arthritis and Alzheimer's disease.

Growing evidence suggests that free radical damage may be an underlying cause of the aging process, thus leaving open the possibility that antioxidants may be able to slow this process.

Beta Carotene

As well as exerting protective effects against various aging-related diseases, beta carotene may protect against memory impairment and other loss of mental function in older people. In a recent Dutch study, researchers studied 5182 people aged 55 to 95 from 1990 to 1993. They found that those with intakes of less than 0.9 milligrams of beta carotene per day were almost twice as likely to have impaired memory, disorientation and problem solving difficulty as those with intakes of 2.1 milligrams of beta carotene.14

Researchers involved in a 1997 Swiss study found similar results. The study, which was reported in the Journal of the American Geriatrics Society, involved 442 men and women, aged from 65 to 94 in 1993. Antioxidant levels were originally tested in 1971 and then again in 1993, when the participants were also given memory-related tests. Higher vitamin C and beta carotene levels were associated with higher scores on free recall, recognition and vocabulary tests.15

Vitamin C

Vitamin C deficiency in elderly people can increase susceptibility to many disorders. Low vitamin C levels are associated with lowered immunity, which increases the risk of infection. In a study published in 1997, French researchers assessed vitamin C levels in 18 elderly patients in hospital. The patients were divided into three groups: those with acute infection, those who were malnourished, and a control group. Those with acute infection had considerably lower vitamin C levels than those in the other groups.16

Low vitamin C intakes also increase the risk of cardiovascular disease in elderly people. During a study which was begun in 1981, USDA researchers assessed the health and nutrition status of 747 elderly people aged 60 years and over. Particular attention was paid to the foods the participants usually ate and the levels in their blood of the antioxidant vitamins C, E and beta carotene. The researchers following up the subjects from nine to 12 years later found that among people who ate lots of dark green and orange vegetables, there were fewer deaths from heart disease and other causes. The results showed that a daily intake of more than 400 mg and higher blood levels of vitamin C were linked to reduced risk of death from heart disease.17

Vitamin E

High vitamin E intakes are linked to lower risks of several disorders including cardiovascular disease, cancer, Parkinson's disease and cataract. Supplements have also shown beneficial effects in several studies.

A study by researchers from the National Institute on Aging, published in 1996, examined the effects of vitamin E and vitamin C supplement on mortality risk in 11 178 persons aged from 67 to 105 who were taking part in the Established Populations for Epidemiologic Studies of the Elderly from 1984 through 1993. During the follow-up period, there were 3490 deaths. The results showed that those using the vitamin E supplements had a 34 per cent lower risk of death when compared to those not using vitamin E supplements, and around half the risk of death from coronary disease. Those taking both vitamin C and vitamin E had a 42 per cent reduced risk.18

Vitamin E supplements also improve the effectiveness of the immune system in elderly people. In a 1997 study of 88 healthy people aged 65 or older, those who took 200 mg (300 IU) each day for about four months showed an improvement in immune response. Researchers assessed the effects of either 60 mg (90 IU), 200 mg (300 IU) or 800 mg (1333) on a measure of immune system strength known as delayed hypersensitivity skin response. The results showed that those who took 200 mg a day had a 65 per cent increase in immune function. Those taking 60 mg or 800 mg of vitamin E also showed some improvements in immune function but the ideal response was seen in those taking 200 mg.19 Vitamin E may also provide relief from some of the symptoms of menopause, particularly hot flashes.20

Many studies suggest that vitamin E supplements are beneficial for elderly people, as it can be difficult to get high levels of vitamin E in the diet. Most studies use doses that range from 536 mg (800 IU) or even 804 mg (1200 IU). Such doses far exceed the RDAs, and it is not possible to get such large amounts of vitamin E from food without consuming a high fat diet.

Calcium

High calcium intakes are associated with reduced risk of some types of cancer and high blood pressure. Optimal calcium intake is particularly important in preventing the bone-thinning associated with osteoporosis. Although the problem also occurs in men, women are at particularly high risk of osteoporosis, with as many as 35 per cent of women suffering from the disease after menopause. Most of the bone loss seen in osteoporosis in postmenopausal women occurs in the first five to six years after menopause due to low calcium intake, a decline in female hormones, and an age-related reduction in vitamin D production.

It is never too late to slow the bone loss seen in osteoporosis and early postmenopausal years are an important time to ensure optimal calcium intake. Some research shows that taking calcium supplements later in life may lower vertebral fracture rate and prevent bone density decrease in elderly people.

Treatment which combines calcium and estrogen is likely to be better at building bone than treatment with estrogen alone. In a 1998 review, researchers analyzed the results of 31 studies and found that the postmenopausal women who took estrogen alone had an average increase in spinal bone mass of 1.3 per cent per year, while those who took estrogen and calcium supplements had an average increase of 3.3 per cent. Increases in bone mass in the forearm and upper thigh were also greater in women taking supplements. The added benefit from the calcium was seen when the women increased their intake from an average of 563 mg per day to 1200 mg per day.21

Iron

Iron deficiency is common in elderly people as they often have reduced stomach acid and therefore reduced absorption ability. Low blood plasma levels of iron can contribute to fatigue, heart disease and deterioration in mental functioning.

Iron requirements are lower in women who have reached menopause as they no longer lose iron in menstrual blood. However, deficiency is still relatively common and all elderly people should ensure they get sufficient iron in their diets. A 1997 National Institute of Aging study suggests that low iron levels are linked to an increased likelihood of death in elderly people. Researchers looked at the iron status of nearly 4000 men and women aged 71 and over. Results showed that low iron levels increased the risk of total and coronary heart disease deaths. Those with higher iron levels had decreased risk. Men with the highest iron levels had only 20 per cent of the risk of dying of heart disease of those with the lowest levels. Women with the highest levels were about half as likely to die of heart disease compared to those with the lowest levels.22

The iron overload disorder, hemochromatosis, can result in increased risk of heart disease, liver problems and other disorders. This is one of the most common inherited diseases in certain groups of people, and middle-aged and older men may be particularly badly affected. Iron supplements should be avoided in these cases.

Magnesium

Marginal magnesium deficiency is considered to be very common, especially in the elderly. Inadequate intake may contribute to cardiovascular disease, high blood pressure, osteoporosis, diabetes and various other disorders. Supplements are likely to be beneficial in older people.

Selenium

Selenium is a vital part of the antioxidant enzyme, glutathione peroxidase, and so may protect against free radical damage and its consequences. It is also necessary for thyroid and immune system function, which may be disrupted in older people. Optimal intake may also help combat psychological disorders like depression, anxiety, fatigue and appetite loss.

Sodium

Sodium restriction may be a useful way to lower blood pressure in elderly people suffering from hypertension. In a two-month double-blind, randomized, placebo- controlled crossover study published in 1997 in The Lancet, researchers found that modest reduction in salt in the diets of elderly people led to lower blood pressure. The study involved 29 patients with high blood pressure and 18 with normal blood pressure. The average blood pressure fall was 8.2/3.9 mmHg in the normal subjects and 6.6/2.7 mmHg in those with high blood pressure.23 In those with normal blood pressure, cutting salt may have little effect, according to an analysis of 83 studies published in the Journal of the American Medical Association in 1998.24

Zinc

Inadequate consumption of zinc-rich foods can result in reduced sense of taste and possibly lead to reduced appetite or increased consumption of sugary or salty foods that may aggravate malnutrition. Zinc is vital for wound-healing and an effective immune response, and a deficiency can leave elderly people susceptible to infection and prolong recovery from illness. Elderly people often have zinc-poor diets and low blood levels.

Menopause

Menopause is when a woman's menstrual periods stop altogether and a woman is said to have gone through menopause when her menstrual periods have stopped for an entire year. This usually occurs between the ages of 45 and 55, although it can happen as early as 35 or as late as 65 years of age. It can also result from the surgical removal of both ovaries. The physical and emotional signs and symptoms that go with menopause usually last around one to two years or more, and vary from woman to woman. The changes are a result of hormonal changes such as estrogen decline, the aging process itself, and stress.

The physical signs and symptoms associated with menopause may include hot flushes, heart palpitations, irregular periods, vaginal dryness, loss of bladder tone, headaches, dizziness, skin and hair changes, loss of muscle strength and tone, and decreased bone mineral density. Emotional changes associated with menopause may include irritability, mood changes, lack of concentration, difficulty with memory, tension, anxiety, depression and insomnia.

Hormone replacement therapy (HRT) is often used to reduce many of the symptoms of menopause. It also offers significant protection against osteoporosis and heart disease. However, it may increase the risk of certain types of cancer and some women are unable or unwilling to use HRT.

Regular exercise and stress reduction techniques can be helpful in reducing the symptoms of menopause. Dietary measures that may be beneficial include limiting or avoiding drinks that contain caffeine or alcohol, spicy foods, and heavy meals. Soy foods such as tofu, which contain compounds known as phytoestrogens, have been shown to reduce menopausal symptoms in many women. A woman's risk of disorders such as heart disease and osteoporosis increases after menopause, and the various dietary measures and supplements outlined above can be used to prevent these.

Herbal Medicines and Older People

There are many herbs that can be beneficial for older people. These include tonics such as ginseng (Panax ginseng and Eleutherococcus senticosus), which can improve vitality and resistance to disease; ginkgo (Ginkgo biloba), which can improve mental function; damiana (Turnera diffusa), which can boost libido; ginger (Zingiber officinale), which can improve circulation; and hawthorn (Crataegus oxyacantha), which is a heart tonic. Herbs which may be useful during menopause include chaste tree (Vitex agnus castus), St John's wort (Hypericum perforatum), motherwort (Leonurus cardiaca), dong quai (Angelica sinensis), and black cohosh (Cimicifuga racemosa).

 

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2 Fisher GJ; Wang ZQ; Datta SC; Varani J; Kang S; Voorhees JJ. Pathophysiology of premature skin aging induced by ultraviolet light. N Engl J Med, 1997 Nov, 337:20, 1419-28

3 Wilkinson TJ; Hanger HC; Elmslie J; George PM; Sainsbury R. The response to treatment of subclinical thiamine deficiency in the elderly. Am J Clin Nutr, 1997 Oct, 66:4, 925-8

4 van der Wielen RP; Löwik MR; Haller J; van den Berg H; Ferry M; van Staveren WA Vitamin B-6 malnutrition among elderly Europeans: the SENECA study. J Gerontol A Biol Sci Med Sci, 1996 Nov, 51:6, B417-24

5 Quinn K; Basu TK. Folate and vitamin B12 status of the elderly. Eur J Clin Nutr, 1996 Jun, 50:6, 340-2

6 Ortega RM; Mañas LR; Andrés P; Gaspar MJ; Agudo FR; Jiménez A; Pascual T Functional and psychic deterioration in elderly people may be aggravated by folate deficiency. J Nutr, 1996 Aug, 126:8, 1992-9

7 Fata FT; Herzlich BC; Schiffman G; Ast AL. Impaired antibody responses to pneumococcal polysaccharide in elderly patients with low serum vitamin B12 levels. Ann Intern Med, 1996 Feb, 124:3, 299-304

8 Nilsson Ehle H Age-related changes in cobalamin (vitamin B12) handling. Implications for therapy. Drugs Aging, 1998 Apr, 12:4, 277-92

9 Thomas MK; Lloyd Jones DM; Thadhani RI; Shaw AC; Deraska DJ; Kitch BT; Vamvakas EC; Dick IM; Prince RL; Finkelstein JS. Hypovitaminosis D in medical inpatients. N Engl J Med, 1998 Mar, 338:12, 777-83

10 McAlindon TE; Felson DT; Zhang Y; Hannan MT; Aliabadi P; Weissman B; Rush D; Wilson PW. Relation of dietary intake and serum levels of vitamin D to progression of osteoarthritis of the knee among participants in the Framingham Study. Ann Intern Med, 1996 Sep, 125:5, 353-9

11 Dawson Hughes B; Harris SS; Krall EA; Dallal GE Effect of calcium and vitamin D supplementation on bone density in men and women 65 years of age or older. N Engl J Med, 1997 Sep, 337:10, 670-6

12 Lips P, Graafmans WC, Ooms ME, Bezemer PD, Bouter LM. Vitamin D supplementation and fracture incidence in elderly persons. A randomized, placebo-controlled clinical trial. Ann Intern Med 1996 Feb 15;124(4):400-406

13 Buckley et al.Calcium and vitamin D3 supplementation prevents bone loss in the spine secondary to low-dose corticosteroids in patients with rheumatoid arthritis. A randomized, double-blind, placebo-controlled trial. Ann Intern Med 1996 Dec 15;125(12):961-968

14 Jama JW; Launer LJ; Witteman JC; den Breeijen JH; Breteler MM; Grobbee DE; Hofman A. Dietary antioxidants and cognitive function in a population-based sample of older persons. The Am J Epidemiol, 1996 Aug, 144:3, 275-80

15 Perrig WJ; Perrig P; Stähelin HB The relation between antioxidants and memory performance in the old and very old. J Am Geriatr Soc, 1997 Jun, 45:6, 718-24

16 Pfitzenmeyer P; Guilland JC; dAthis P. Vitamin B6 and vitamin C status in elderly patients with infections during hospitalization. Ann Nutr Metab, 1997, 41:6, 344-52

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19 Martin A; Foxall T; Blumberg JB; Meydani M. Vitamin E inhibits low-density lipoprotein-induced adhesion of monocytes to human aortic endothelial cells in vitro. Arterioscler Thromb Vasc Biol, 1997 Mar, 17:3, 429-36

20 Barton DL et al. Prospective evaluation of vitamin E for hot flashes in breast cancer survivors. J Clin Oncol, 1998 Feb, 16:2, 495-500

21 Nieves JW, Komar L, Cosman F, Lindsay R. Calcium potentiates the effect of estrogen and calcitonin on bone mass: review and analysis. Am J Clin Nutr 1998;67:5-6, 18-24

22 Corti MC; Guralnik JM; Salive ME; Ferrucci L; Pahor M; Wallace RB; Hennekens CH. Serum iron level, coronary artery disease, and all-cause mortality in older men and women. Am J Cardiol, 1997 Jan, 79:2, 120-7

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24 Graudal NA et al. Effects of Sodium Restriction on Blood Pressure, Renin, Aldosterone, Catecholamines, Cholesterols, and Triglyceride. JAMA. 1998;279:1383-1391