Nestle Supplement 2

NUTRITION AND THE OLDER PERSON increased risk of morbidity and mortality in obese individuals, while overweight status is less clearly associated with excess deaths.25,34,35 Weight loss in middle-aged adults, as shown in numerous clinical trials, improves or completely normalizes the cluster of metabolic abnormalities linked to obesity.18 Even modest weight loss (5%–10%) can improve risk factors associated with coronary heart disease.19 Similar benefits appear to be achievable in obese older persons.36 Lifestyle intervention including diet and exercise therapy improved metabolic syndrome, lipid profile, and inflammatory markers in obese adults age 65 years and older.18 Two separate trials in overweight post-menopausal women (mean ages 57 and 60 years) improved coronary heart disease risk factors and glucose tolerance via weight loss mediated by hypocaloric diet and low-intensity exercise.37,38 Weight gain throughout life exacerbated risk of hypertension in predisposed women aged 40–70 years while weight loss significantly lowered the risk.39 Mechanical complications of obesity, such as osteoarthritis and respiratory problems, improve with weight loss even in the very old.40 The aforementioned benefits of weight loss pertain more to obese rather than overweight older adults18 and must be weighed against unintentional adverse consequences of calorie restriction and weight loss in the elderly.5,27 Suboptimal nutrient intake or even malnutrition is a very real risk in older people, decreasing already limited calories. Requirements for specific nutrients increase in the face of diminishing calorie needs with aging thereby necessitating nutrient dense diets.2 Protein intake, in particular, must be maintained and even increased in older individuals restricting calories. Dietary protein and amino acids represent one of the most effective means to slow or prevent muscle protein catabolism.20 Blunting of the anabolic response in elderly due to changes in digestion, gastric emptying, splanchnic uptake, and peripheral utilization can be overcome by strategically timing the ingestion of appropriate amounts of protein or amino acid supplements.12 Protein also protects against age-related loss of bone mineral density as do vitamin D and calcium. Decreased ability to synthesize vitamin D and potential issues with lactose intolerance often lead to compromised status of these nutrients.41 Animal protein intake often decreases with aging due to dentition issues, satiety induced by these foods, and issues related to cost and convenience.12 Consequently, nutrients at risk of suboptimal intake include iron, zinc, and vitamin B12. In many elderly individuals, vitamin B12 status is further compromised by food-bound malabsorption.42 Nutritional supplements may be the only means to meet nutritional needs in older adults restricting their calorie intake. Weight loss inevitably 20 • DECEMBER 2007 includes loss of muscle and bone mass, which appears to be proportionately similar in young and old but may have a more profound impact on body composition of older adults already experiencing loss of lean tissue. Newman43 reported on percentage changes in lean and fat compartments with weight loss and weight gain in 70–79-year-old adults. Lean mass compared to fat mass represented a significantly greater percentage of weight loss, whereas weight gain was predominantly represented by fat mass.The implications of this trade-off are serious, particularly if weight is cyclically lost and regained in the aging person. The key issue in determining the balance between potential beneficial effects as opposed to detrimental effects of weight loss in elderly revolves around maintenance of the muscle mass. The importance of muscle mass, strength, and metabolic function in the performance of exercise, as well as the activities of daily living (ADL), is obvious.44 Perhaps less well recognized, muscle plays a central role in whole-body protein metabolism that is particularly important in the response to stress.20 In the post-absorptive state, essential tissues and organs, such as brain, skin, and liver, rely on a steady supply of amino acids via the blood to serve as precursors for the synthesis of new proteins to balance the persistent rate of protein breakdown that occurs in all tissues. In the absence of nutrient intake (ie, between meals), muscle protein serves as the principal reservoir to replace blood amino acid taken up by other tissues.45 The stressed state, such as in sepsis, advanced cancer, and following traumatic injury, imposes greater demands for amino acids from muscle protein breakdown than fasting.46 Physiological responses necessary for recovery may include accelerated synthesis of acute phase proteins in the liver, proteins involved in immune function, and proteins involved in wound healing. Net breakdown of muscle protein is stimulated to provide abundant amino acids to meet these increased demands. This response is not readily reversed, even by aggressive nutritional support.46 Not surprisingly, individuals with limited reserves of muscle mass respond poorly to stress. For example, loss of muscle mass is known to be detrimental to survival from cancer.47 In addition to the physiological role of muscle in the response to serious illness and stress, abundant evidence points to a key role of altered muscle metabolism in the genesis and, therefore, prevention of many common pathological conditions and chronic diseases. Both cardiac failure and cancer are often associated with rapid and extensive loss of muscle mass, strength, and metabolic function (cachexia). In the case of both cardiac and cancer cachexia, the loss of muscle mass is an important determinant of

Table of Contents Feed for the Digital Edition of Nestle Supplement 2

Nestle Supplement Table of Contents Introduction to Weight Loss in Older Persons Diagnosis and Management of Oropharyngeal Dysphagia in the Elderly The Danger of Weight Loss in the Elderly Nutrients and Frailty

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.