I'm sure everyone here knows this already, but it's good to see moar evidence.

Obesity Paradox during Aging

Abstract: 'Although obesity in young people is a risk factor for morbidity and mortality, the effect of obesity in
the elderly is much more complex. For example, the body weight associated with maximal survival
increases with increasing age. Even more striking is the ‘obesity paradox’ in the elderly, in which
overweight is associated with increased risk for cardiovascular disease but decreased mortality from
these diseases. Thus, although intentional weight loss by obese older people is probably safe, and
likely to be beneficial if they have obesity-related morbidities, caution should be exercised in recommending
weight loss to overweight older people on the basis of body weight alone. Methods of
achieving weight loss in older adults are the same as in younger adults. Weight loss diets should be
combined with an exercise program, if possible, to preserve muscle mass, as dieting results in loss of
muscle as well as fat, and older people have reduced skeletal muscle mass compared to younger
adults. Weight-loss drugs have not been extensively studied in older people and there is the potential
for drug side effects and interactions. Weight loss surgery appears to be safe and effective,
although it probably produces less weight loss than in younger adults. Little is yet known about the
outcomes of such surgery in people over 65 years.'

http://www.google.co.uk/url?sa=t&rct...74649129,d.d2s

From the main text:

'In young adults, obesity tends to be associated with increased skeletal muscle, acquired
to support the extra weight. In contrast, in older people, excess weight, to the point
of obesity, can co-exist with muscle loss and even sarcopenia. Hence, the existence of
sarcopenic obesity, or the ‘skinny fat’ elderly, who have high levels of body fat but do
not look overweight as they have lost much of their lean tissue. This combination in
people with sarcopenic obesity of an excess of (possibly) metabolically bad fat tissue
and a deficiency of beneficial muscle is associated with particularly adverse effects
[20]. In one prospective study of elderly people followed for up to 8 years, those with
sarcopenic obesity (skeletal muscle mass more than 2 SDs below young adult mean
AND percentage body fat above the 60th percentile) at baseline were 2–3 times more
likely to develop disabilities in activities of daily living than were lean sarcopaenic,
nonsarcopenic obese or normal body composition subjects [21]. The age-related
loss of skeletal muscle and its adverse effects probably helps explain the consistently
demonstrated benefits of exercise programs in elderly people, particularly those that
increase muscle mass and function.'

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