The surprising reason people over age 65 should never eat rare meat

Everybody is looking for anti-aging secrets. Not surprisingly, a number of them involve the way you eat, because a poor diet can lead to a weakened immune system, nutritional deficiencies, and gastrointestinal problems like weight gain, gall stones, and inflammatory bowel disease. So make sure you know which foods are bad for your digestive health. However, now it looks like the way you cook your food can influence how healthy it is: New research from France suggests that for senior citizens, eating steak rare prevents them from absorbing all the protein they need.

Researchers from the Unit of Human Nutrition, at the French National Institute for Agricultural Research, and the Center for Research in Human Nutrition Auvergne at Clermont-Ferrand University Hospital, France, recruited 10 elderly volunteers aged 70 to 82 years for their clinical trial. On a couple of different occasions, the volunteers ate a steak that was cooked rare; on other days, they had a steak that was well-done.

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Blood tests done after the volunteers had eaten revealed that they absorbed far fewer key amino acids—building blocks for protein—when the meat was rare, compared to when they ate well-done steaks. “In view to preventing sarcopenia [the degenerative loss of muscle mass, quality, and strength that comes with age] elderly subjects should be advised to favor the consumption of well-cooked meat,” say the researchers.

Young people are able to digest rare and well done meat about the same, note the authors of the study, which was recently published in The American Journal of Clinical Nutrition. But the findings suggest that people over 65 should eat their beef well done to glean the most from a meal. Their digestive systems struggle to break down protein in rare meat—and protein is crucial for building, maintaining, and replacing muscle and organs, and to keep the heart and lungs healthy.

If you’re struggling with digestion, check out these four food rules for better gut health whatever age you are.

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