DRAFT Australian Dietary Guidelines - Eat For Health

4.4.5 Older people
Older people should eat nutritious foods and keep physically active to help maintain muscle
strength and a healthy weight.
Daily energy expenditure declines throughout adult life, as does physical activity [44]. Energy
expenditure is dependent on fat-free mass, which decreases by about 15% between the third and
eighth decades of life, contributing to lowered metabolic rate in older people [840]. The decrease
in energy expenditure is generally accompanied by decreased appetite and diminished food intake,
so may account for the undernutrition seen in some older people [841]. While overweight and
obesity are still prevalent in older adults [842], consideration of overall morbidity and mortality
suggests that for obese older people a substantial reduction of the BMI may not provide the
healthiest long-term option [843]. Although weight loss achieved by following a nutrient-dense diet
and increasing physical activity may confer benefits, this is still to be tested in good quality trials
[842]. Lowering blood pressure and normalising blood lipids rather than reducing weight may be
more appropriate for elderly overweight people [844].
Older people commonly have a decrease in skeletal muscle mass and strength, which is the result
of a decline in the production of muscle tissue [844]. Height may also decrease with age as a result
of changing spinal shape and intervertebral thickness, making it difficult to determine height and
therefore BMI.
While most of the elderly population live independently, it has been estimated that 25–40% of
those over 80 years of age could be considered frail [845]. Malnutrition in the elderly is often
associated with one or more illnesses such as chronic obstructive lung disease and heart failure,
dementia, dysphagia, poor dentition, depression, social isolation, use of drugs, alcohol and other
substance abuse, poverty, and despair [845, 846]. In Australia 5–11% of people eligible for Home
and Community Care services are malnourished [847]. In acute care, 20–30% of people are
admitted with malnutrition, the prevalence increasing with age and the number of health problems
[847, 848]. Older people can develop sarcopenia, a form of muscle wasting, and some older
people also experience sarcopenic obesity, where there is a combination of reduced muscle mass
and/or strength and excessive body fat [842].
Recent studies suggest that, for an older person, being underweight may be more deleterious for
health than being overweight [716]. A BMI range of 23–28 is considered desirable for people over
70 years of age [709].
The decline in energy expenditure with ageing must be balanced by adjusting energy intake to
maintain body weight within the healthy range and to prevent an increase in body fat [9]. Dietary
patterns and quantities consistent with the Foundation and Total Diets are for older people who are
generally fit and well [10]. However low-fat diets are not appropriate for the frail elderly or those
with complex health conditions [35, 844].
DRAFT Australian Dietary Guidelines- December 2011 128