1000 2000 3000 Survival time (days)

Figure 2 Probability of survival for participants from the SENECA study with and without weight change in the first 4years. (Reproduced from Thomas D (ed.) (2002) Undernutrition in older adults. Clinics in Geriatrics 18(4), with permission of WB Saunders.)

on Nutrition and the Elderly, a Concerted Action (SENECA). Weight loss (>5kg over 4years) seemed to be predictive for survival. It is even more important to be slightly overweight than underweight for people older than age 70 years. Therefore, except for those who are obese, elderly people should be encouraged to maintain an adequate energy intake. According to the SENECA study, 20-25% of the relatively healthy participants failed to do so: Approximately 8% lost and 16% gained at least 5 kg of body weight over a period of 4 years. When appetite is reduced, an increase in meal frequency may not only help to promote energy intakes but also prevent blood glucose levels from declining steeply.

Body Water, Dehydration, and Medication

Because lean tissue has a high water content, there is a decrease in total body water—especially extracellular water—with advancing age from 80% at birth to 60-70% after age 70 years. In addition, older people experience diminished sensation of thirst, and urinary concentrating ability declines as a function of age. Thus, older people have an increased risk of dehydration, particularly when diuretic or laxative medicines are used or in the presence of some diseases common in old age, such as diarrhea, renal disease, and infection with fever. Because water is essential to all biological functions, fluid intakes during old age should be at least 1700 ml per day. In the body, water acts as a dilutent for water-soluble drugs. Given the decrease in body water with age, older people may need lower dosages of water-soluble drugs than younger adults to achieve the desired therapeutic effect and to avoid drug toxicity.

Food Allergies

Food Allergies

Peanuts can leave you breathless. Cat dander can lead to itchy eyes, a stuffy nose, coughing and sneezing. And most of us have suffered through those seasonal allergies with horrible pollen counts. Learn more...

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