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British Geriatrics Society Best Practice Guide Healthy Eating for Older People January 2011 1. Executive Lay Summary The inextricable link between nutrition and health has been recognised for millennia: that the diet has to be sufficient but not excessive in energy for the body’s needs and contain essential minerals and vitamins. In rich nations the emphasis of public concern has shifted from under-nutrition to excess but it is important to remember that it is under-nutrition that has the worse outlook especially for older people. There is also an industry devoted to selling us health foods and supplements. Assessing the benefits of these for an older individual is often difficult. 2. Introduction The principles of a healthy diet, namely to provide sufficient energy and nutrients to prevent deficiency while also helping to optimise health and reduce the risks of disease [1], are no different in older age than they are at any other time of life but there are particular challenges in achieving them for some older people. The Food Standards Agency (FSA) website gives structured advice on healthy eating accessed through “The eatwell plate” link on its homepage [2]. This in turn links to a section dedicated to older people in “Ages and stages” that sets out principles under the following headings: What to eat, keeping healthy, eating less, keeping food safe, drinking enough, vitamins, cut down salt [3]. 3. What to eat A balanced diet, ideally freshly prepared, with fruit and vegetables as well as food containing starch and protein is the foundation for healthy eating. Some older people rely on reheated frozen meals and other convenience foods. Frozen and canned foods generally preserve the nutritional value of foods very well. Convenience foods from the supermarket often have high levels of salt, sugar and fat, which risks (inadvertent) excessive calorie intake for the obese. o Bread, rice, pasta, cereals and potatoes. Foods rich in starch and fibre, if whole grain, and which are low in fat while being good sources of protein, B vitamins and minerals such as calcium and iron. o Lean red meat, pulses (such as peas, beans and lentils), fish, (particularly oily fish such as sardines), eggs and nuts provide protein, iron, B vitamins, zinc, magnesium. Oily fish also provide vitamin D. o Fruit, especially citrus fruit, green vegetables, peppers, tomatoes and potatoes provide vitamin C, potassium and folate. Bread and breakfast cereals that have added vitamins, are also good sources of folate. o Milk, cheese and yoghurt, in low fat varieties, provide protein and calcium. Canned fish with bones, such as sardines also provide calcium, other sources of which include green leafy vegetables, such as broccoli and cabbage (though not spinach), soya beans and tofu. January 2011 4. Keeping healthy – healthy weight Underweight or overweight which is worse? Between 1993 and 2007 the prevalence of obesity (BMI >30) in adults (over 16 years old) in the Health Survey for England samples rose from 15% to 24% while the prevalence of overweight (BMI 25-30) and underweight (BMI < 18.5) stayed constant: overweight at around 38%, underweight < 2% [4]. The increase in obesity in adults was greatest in the age range 65-74 and especially in women and has been the focus of much political and media attention. Obesity – Witham and Avenell [5] have recently reviewed studies of interventions aimed at achieving weight loss for a minimum of a year in older obese subjects. Compared with younger people they found that there is very little research on the benefits of weight reduction in older obese people though intentional weight loss has been shown to reduce all-cause mortality in males aged 56-75 years. Significant though modest reductions in weight are achievable, more consistently so in trials where dietary advice was combined with increased physical activity. There seem to be no good quality studies of older people that have compared diet and exercise interventions with diet alone but the apparent greater benefits of combined diet and exercise regimes found in the review are consistent with studies using this design in younger subjects. Interventions in the studies reviewed by Witham and Avenell are highly heterogeneous ranging from “counselling to remove barriers to dietary change” and “social action theory” to specific 500-750 kcal/day reduction targets and specific targeted supervised exercise programmes. Not surprisingly studies with specific goals achieved greater weight reduction though no significant improvements in exercise capacity, physical function, quality of life or in cardiovascular events or risk factors emerged from the meta-analysis. For recommendations on exercise see BGS Best Practice Guide “Physical Activity in Old Age”. A previous systematic review [6] which included shorter duration studies of weight reduction, showed probable clinically beneficial outcomes in physical activity, osteoarthritis and hypertension and possibly also in type-II diabetes and coronary heart disease. This review excluded studies in which the weight loss achieved was less than 2 kg or 3% of baseline over 6 months. Witham and Avenell point out that this introduces potential bias which could affect the review’s conclusions but it may suggest that achieving greater weight loss is more likely to be of significant benefit. However the benefits shown in shorter duration studies may not be sustainable. Underweight – Despite the population statistics on overweight and obesity, eating less and unintentional weight loss are common in older people. Surveys of admissions to hospital and to care homes consistently find that underweight older people form a much higher proportion than those who are overweight. The incidence of under-nutrition among patients admitted to hospitals in UK is around 28% [7]. Because those with under-nutrition have longer lengths of stay the corresponding prevalence is nearer 40% [7] as found in the classic study by McWhirter and Pennington [8]. The prevalence is 25% greater in older subjects [7]. Comparable numbers have been found in a study in the Netherlands [9]. In UK care homes 28% of residents were found to be undernourished [7]. A number of studies have now shown that the relative risk of death is consistently highest in those underweight than those overweight and in older people this may be even higher than those who are obese [10,11]. The complex interactions between factors that lead many older people to have reduced energy intakes have been comprehensively reviewed by Roberts and Rosenberg [12]. January 2011 Sarcopenia – Age-related loss of muscle mass and strength is an important factor in frailty. Weakness is characteristically out of proportion to the loss of muscle mass. This has been termed loss of muscle quality and is a strong predictor of poor outcomes. Nutrition plays only a small part in the complex aetiology of the agerelated decline in muscle quality [13] but there is evidence that muscle protein synthesis in response to oral essential amino-acids is reduced in older men [14]. This may be particularly relevant after bed rest which has been shown to lead to greater levels of muscle weakness in older than younger people and which may be improved by essential amino acid supplementation [15]. Recent expert panel recommendations include raising the total protein intake in older people above the current US recommended daily allowance of 0.8 g/kg/day while recognising that up 40% of men and women over 50 years do not consume even this amount [16]. There is also interest in the possibility that vitamin D insufficiency may be a factor in the development of muscle weakness in older people [13]. Vitamin D levels should be measured in weak older people and supplements given if levels are low [16]. Sarcopenic obesity, severe muscle weakness which may be associated with obesity, is a predictor of particularly poor outcomes [17]. Resistance exercise is the only known treatment for this condition [16]. For recommendations on exercise see BGS Best Practice Guide “Physical Activity in Old Age”. Dental health deserves greater emphasis. The National Diet and Nutrition Survey made very detailed studies of the effects of being edentulous on nutritional status showing that intakes of non-starch polysaccharides, protein, calcium, iron, niacin and vitamin C were significantly lower in the edentulous [18]. Dietary counselling has been shown to be effective in improving fruit and vegetable intake in edentulous people [19]. The FSA point out that tinned or stewed fresh fruit and vegetables are still good sources of nutrients for those with difficulty chewing. Keeping food safe – the FSA emphasises the importance of food hygiene and gives the example of the increased risk from listeria with age especially those with impaired immune function [20]: Camembert, brie and other cheeses that have a similar rind, soft blue cheese, all types of pâté, including vegetable, can contain listeria. Drinking enough – older people should aim to drink about 6 to 8 glasses (1.2 litres or just over 2 pints) of water every day to avoid getting dehydrated due to reduced thirst, increasing this when the weather (and/or room temperature) is warm or with increase in activity. Other non-alcoholic fluids may obviously substitute for water though it is important to remember that fruit drinks may contain too much sugar. o It's fine to drink tea and coffee: strong tea and/or coffee should be balanced with drinks of water or other fluids each day that do not contain caffeine. Caffeine causes bladder overactivity which risks urinary incontinence. o What about alcohol? While there is evidence of a rising incidence of problem drinking in older people, there is strong evidence that light / moderate intake of alcohol has significant health benefits in old age. This J-shaped protective curve appears to have maximum protection with an intake of approximately 1-2 units/day [21] with studies confirming reduced overall [22] and cardiovascular mortality [23] across all age groups but particularly in older adults, the group most likely to gain benefit from risk reduction. Furthermore, light / moderate January 2011 o alcohol has been associated with reduced risk of substantial functional health decline, better cognition, psychological well being and improved quality of life in older populations [24]. This amount of alcohol is around 14 units per week, or 2 units per day – this is one pint of beer or 1.5 small glasses of wine a day. What are the safe limits for alcohol intake? Safe limits for older people are probably the same as for younger adults and are 21 units a week for men and 14 units a week for women. However, older people on multiple drugs should probably restrict intake to one unit a day. Those liable to falling similarly should restrict their intake, or indeed avoid alcohol completely. Even moderate alcohol intake in nonalcoholic older subjects has been associated with impaired nutritional status [25]. 5. Vitamins and Minerals Particular care should be paid to ensure sufficient intakes of the following nutrients: vitamin D, calcium, vitamin C, vitamin B12, folate, iron, zinc, magnesium and vitamin B6. With the probable exception of vitamin D, this can generally be achieved by an adequate and balanced diet, as outlined above. The FSA website has a link to a “Vitamins and minerals” section [26] and there is a comprehensively referenced American website [27]. These sites are useful in evaluating what might be the benefits of nutritional supplements which are estimated to be taken by a third of the UK population [1]. The levels of many vitamins and minerals tend to be lower in older people. Thus though not fulfilling the criteria for deficiency there may be insufficiency which it has been postulated could be clinically relevant in some circumstances. Examples only can be discussed here. o Vitamin D: There is debate about the optimum level of vitamin D and of the benefits of vitamin D supplementation. The best established benefit of vitamin D is on bone health. However it may also have important roles in muscle function and immune status and low levels have been associated with increased risks of cancer and vascular disease. The UK reference nutrient intake (RNI) is 10 micrograms (mcg) (400iu) per day which may be too low to achieve adequate vitamin D levels in some people. Insufficiency with associated secondary hyperparathyroidism may contribute to the development of osteoporosis [28]. There is evidence that supplements containing at least 800 iu daily are needed for the prevention of osteoporotic fractures [29]. o Folate: The potential benefits have been the subject of a recent Cochrane review [30]. Folate deficiency may result in megaloblastic anaemia but rarely neurological damage. Folate supplementation in the presence of vitamin B12 deficiency can cause irreversible neurological damage. Lesser levels of folate “insufficiency” are associated with increased blood homocysteine levels which have been associated with vascular disease and dementia. In one study in which healthy people with high homocysteine levels were specifically recruited and given three years folate supplementation, benefits in cognitive function were shown. However there is as yet no convincing evidence of improvement in cognition in unselected older people with either folate supplementation alone or given with vitamin B12. January 2011 o Vitamin B12: Absorption of food-bound B12 requires gastric acid for its release from protein. Gastric acid secretion tends to decrease with age and many older people are on drugs that diminish gastric acid. B12 supplements are not protein bound so are not affected by reduction in gastric acid. Mild pre-clinical deficiency of B12 may be associated with metabolic abnormalities and possibly neurological consequences though as with folate this requires further study [30,31] Cut down salt Most of the salt we eat is already in foods, and so it is important to be aware of the salt content of ready-prepared foods. Recommended average daily salt intake is less than 6g per day (about 2.4g of sodium). The FSA website advocates the avoidance of adding salt to food when cooking and at the table [3]. This is sound advice though may not be realistic as such meals tend to taste bland and this may even result in reduced overall intake. Potassium intake needs to balance the beneficial effect on blood pressure (fruits such as bananas, tomatoes and avocados) with the risk of hyperkalaemia. 6. Responsibilities / Role of the Geriatrician It is the responsibility of all geriatricians to include assessment of nutritional status as part of the comprehensive geriatric assessment and to be aware of the contributions that both under- and over-nutrition may make to health and functional problems in older people. It is also important to be aware of the important role dieticians play in the management of nutritional problems. Press coverage of nutrition stories tends to be enthusiastic but unbalanced. For example recent coverage of the possible link between calcium supplements and heart attacks on the one hand and of vitamin B “the revolutionary new weapon against Alzheimer’s” (Telegraph.co.uk) on the other. Geriatricians will be asked about these headline making stories and it is their responsibility to keep abreast of the medical literature in order to be able to give balanced advice. 7. Audit Audit of the effectiveness of nutritional assessment and of the management of nutritional problems especially under-nutrition should be regularly undertaken in departments of geriatric medicine (cf Best Practice Guide “Nutritional Advice in Common Clinical Situations”). 8. Training Departments of geriatric medicine should train their juniors who are working in acute, rehabilitation and intermediate care settings in the importance of nutritional assessment and optimising nutritional intake of their patients (cf Best Practice Guide “Nutritional Advice in Common Clinical Situations”). 9. References 1. Manual of Dietetic Practice 4th edition 2007, Thomas B, Bishop J (eds), Oxford, Blackwell Publishing 2. Food Standards Agency: http://www.eatwell.gov.uk/healthydiet/ 3. Food Standards Agency: http://www.eatwell.gov.uk/agesandstages/olderpeople/ 4. http://www.ic.nhs.uk/statistics-and-data-collections/health-and-lifestyles-relatedsurveys/health-survey-for-england/health-survey-for-england--2008-trend-tables 5. Witham MD & Avenell A Interventions to achieve long-term weight loss in January 2011 obese older people. A systematic review and meta-analysis. Age and Ageing 2010; 39: 176– 184 6. Bales CW & Buhr G Is Obesity Bad for Older Persons? A Systematic Review of the Pros and Cons of Weight Reduction in Later Life. J Am Med Dir Assoc 2008; 9: 302–312 7. Elia M, Jones B & Russell C (2008) Malnutrition in various care settings in the UK: the 2007 Nutrition Week survey. Clinical Medicine, 8, 364-5 8. McWhirter JP & Pennington CR (2004) Incidence and recognition of malnutrition in hospital. BMJ, 308, 945-8 9. Kruizenga HM, Wierdsma NJ, van Bokhorst MA et al (2003) Screening of nutritional status in the Netherlands. Clinical Nutrition, 22, 147-52 10. Flegal KM et al Excess Deaths Associated With Underweight, Overweight, and Obesity JAMA. 2005;293:1861-1867 11. Orpana HM et al. BMI and Mortality: Results From a National Longitudinal Study of Canadian Adults Obesity (2009) 18, 214–218 12. Roberts SB & Rosenberg I. Nutrition and aging: changes in the regulation of energy metabolism with aging. Physiol Rev. 2006; 86: 651-67 13. Narici MV & Maffulli N Sarcopenia: characteristics, mechanisms and functional significance British Medical Bulletin 2010; 1–21 14. Cuthbertson D et al 2005, FASEB, 19, 422-4 15. Ferrando AA et al EAA supplementation to increase nitrogen intake improves muscle function during bed rest in the elderly Clinical Nutrition 2009; 29: 18-23 16. Morley JE et al Nutritional Recommendations for the Management of Sarcopenia. J Am Med Dir Assoc 2010; 11: 391–396 17. Stenholm S et al Sarcopenic obesity - definition, etiology and consequences Curr Opin Clin Nutr Metab Care. 2008; 11: 693–700 18. Marcenes W et al The relationship between dental status, food selection, nutrient intake, nutritional status, and body mass index in older people Cad. Saúde Pública, Rio de Janeiro, 2003;19: 809-816 19. Bradbury J et al Nutrition Counseling Increases Fruit and Vegetable Intake in the Edentulous J Dent Res 2006; 85:463-468 20. Gillespie IA et al Disease Presentation in Relation to Infection Foci for Non-PregnancyAssociated Human Listeriosis in England and Wales, 2001 to 2007 Journal of Clinical Microbiology 2009; 47: 3301-7 21. Costanzo S et al. Alcohol Consumption and Mortality in Patients With Cardiovascular Disease. J Am Coll Cardiol 2010; 55: 1339–47 22. White IR et al. Alcohol consumption and mortality: modelling risks for men and women at different ages BMJ;2002: 325: 191 23. Hvidtfeldt UA et al. Alcohol intake and risk of coronary heart disease in younger, middleaged, and older adults. Circulation. 2010;121:1589-97 24. Chen LY & Hardy CL. Alcohol Consumption and Health Status in Older Adults: A Longitudinal Analysis. J Aging Health 2009; 21: 824-47 January 2011 25. Jacques PF et al. Moderate alcohol intake and nutritional status in nonalcoholic elderly subjects. Am J Clin Nutr. 1989; 50: 875-83. 26. http://www.eatwell.gov.uk/healthydiet/nutritionessentials/vitaminsandminerals/ 27. Linus Pauling Institute, Micronutrient Information Center, Oregon State University http://lpi.oregonstate.edu/infocenter/vitamins.html & http://lpi.oregonstate.edu/infocenter/minerals.html 28. Francis RM What do we currently know about nutrition and bone health in relation to United Kingdom public health policy with particular reference to calcium and vitamin D? British Journal of Nutrition 2008; 99: 155–159 29. Bischoff-Ferrari HA et al Prevention of Nonvertebral Fractures With Oral Vitamin D and Dose Dependency Arch Intern Med. 2009; 169: 551-561 30. Malouf R, Grimley Evans J www.cochrane.org/reviews/en/ab004514.html 31. Carmel R Anemia and aging: an overview of clinical, diagnostic and biological issues Blood Reviews 2001; 15: 9–18 Authors: Dr Ian Donald, Dr Stuart Bruce and Dr Julia Newton January 2011