Mainly because metabolic function slows with age.
Because resting metabolism slows with age, decreasing by roughly 1-2 percent every 10 years. Even worse, at least for women, is a shift around menopause: excess fat begins to accumulate. Instead of thickening one's thighs and buttocks, this fat begins to pile up in a layer of swimming circles around the stomach. This phenomenon is of course more common in men.
This change isn't just about being aesthetically pleasing. A larger waist and hips signal an increased risk of heart disease, stroke, diabetes, metabolic syndrome and even some cancers, too, and for both men and women. The shift also helps explain why women's risk of cardiovascular disease begins to catch up with men's after menopause.
Bigger bellies can also be costly, and a 2008 Danish study found that every 1-inch (2.54 centimeters) increase in a healthy waist circumference increased annual health care costs by about 3 percent for women and 5 percent for men.
/iknow-pic.cdn.bcebos.com/4b90f603738da9778005f396be51f8198618e361 "target="_blank "title="" class="ikqb_img_alink">/iknow- pic.cdn.bcebos.com/4b90f603738da9778005f396be51f8198618e361?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1% 2Fquality%2Cq_85%2Fformat%2Cf_auto "esrc="/n1/2018/0626/c1010-30089175.html "target="_blank "title="Effective only when a link is selected for support">People's Daily Online - Why middle-aged people are getting fat.
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