"Malnutrition" refers to undernutrition or overnutrition, either of which creates significant health risks in the elderly. A recent review of nutritional studies in Topics in Clinical Chiropractic covered the incidence and causes of malnourishment in seniors, and brought up the dangers of not eating right.
The review noted that a quarter of all men and half of all women over age 65 in America are considered overweight. Obesity is associated with adult-onset diabetes, high blood pressure, coronary artery disease and several forms of cancer (breast, colon, uterine). Body shape may be more important than a simple weight-height ratio when assessing overnutrition: fat concentrated around or above the waistline (e.g., a potbelly) is more closely associated with cardiovascular diseases, stroke, and diabetes than fat centralized around the hips.
Undernutrition, either from being too thin or lacking certain nutrients, occurs in 5-20% of seniors and is related to increased risk of death, infection, osteoporosis and degenerative diseases. Medical causes may be seen in 93% of undernutrition cases (due to medications seniors are taking); other causes include anorexia, cancer, depression and hypothyroidism. Protein and vitamin/mineral deficiencies are common in undernourished individuals. Although people require fewer calories as they age, they should not reduce nutrient intake.
Nutritional supplements containing vitamin C, B vitamins and zinc may lessen the effects of undernutrition. A diet packed with fruits, vegetables and adequate amounts of protein can provide the best form of absorbable nutrients. If you are overweight, try to shed some extra pounds by eating fewer calories and staying physically active.
Thomas DR, Morley JE. Nutritional considerations in older people. Topics in Clinical Chiropractic 2002:9(2), pp. 7-24.
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