Obesity and its complications raise major challenges for US healthcare, so better understanding its pathophysiology may help a great many people. Traditional caloric restriction has poor long-term outcomes because very few people can stick to dietary limitations forever. Other approaches have similar problems.
This group from the University of Wisconsin took a new tactic with short-term restriction of a single nutrient. Methionine is an amino acid that has high levels in beans, nuts, beef, turkey, pork, fish, eggs, and dairy. The study started with 6-week-old mice fed a high-fat western diet for ten weeks to induce obesity, hepatosteatosis, and hyperglycemia. Some mice continued on this diet, while others received an isocaloric high fat diet without methionine for 5 weeks.
At the end of that time, mice with methionine restriction showed decreased body weight, decreased body fat, less fat in the liver, and improved blood sugars. They looked more like mice on standard chow than high-fat fed mice. Remarkable, considering they were still getting a high-fat diet!
Would this work in people? I don't know if I could do a stringent methionine restriction for a month; look at that food list in the second paragraph! Other strategies might be in order, like swearing off this amino acid one or two days each week or month.
As always, only more research will tell us what might work!