Nearly 80 million Americans are obese, putting them at an increased risk for a litany of metabolic conditions, including heart disease, stroke, and certain types of cancers. But a new study, published in the journal Cell Metabolism, reveals that obese patients who lose just 5 percent of their body weight can dramatically improve many obesity-related conditions.
"Our findings demonstrate that you get the biggest bang for your buck with 5 percent weight loss," said the study’s lead researcher Dr. Samuel Klein, the director of Washington University's Center for Human Nutrition, in a press release." The current guidelines for treating obesity recommend a 5 to 10 percent weight loss, but losing 5 percent of your body weight is much easier than losing 10 percent. So it may make sense for patients to aim at the easier target."
Klein and his research team at Washington University School of Medicine recruited 40 obese patients and assigned them to either maintain their weight or go on a diet to lose 5 percent, 10 percent, or 15 percent of their body weight. Each patient’s organs, body fat content, and hormones were measured before, during, and after the study.
"If you weigh 200 lbs., you will be doing yourself a favor if you can lose 10 pounds and keep it off," Klein concluded. "You don't have to lose 50 pounds to get important health benefits."
The 19 participants who lost only 5 percent of their weight experienced improvement in how their body stored and released insulin, which is key for regulating sugar levels in the blood, along with a decrease in total body fat and fat in the liver, which lowers the chance of becoming diabetic and developing non-alcoholic fatty liver disease. And compared to the nine patients who were assigned to lose 15 percent of their body weight, there wasn’t a big difference in benefits. Their bodies improved how they processed insulin in muscle tissue, helping the body to convert sugar to energy, however they were still unable to properly process sugar through the liver and did not lose any more liver fat.
"Continued weight loss is good, but not all organ systems respond the same way," Klein said. "Muscle tissue responds much more to continued weight loss, but liver and adipose tissue have pretty much achieved their maximum benefit at 5 percent weight loss."
However, losing 5 percent of body weight may not have the same benefits in all obese people. None of the patients were diabetic, despite obesity being the greatest risk factor for developing Type 2 diabetes. The bodies of people who are overweight and obese have trouble regulating insulin, which is a hormone that helps to control blood sugar levels, ultimately leading to dangerous spikes and lows in sugar levels. According to Klein, the study needs to expand to reach obese patients with Type 2 diabetes in order to have a thorough understanding of how weight loss improves the health of all obese patients.
"We don't know whether people with diabetes will have the same response to this type of progressive weight loss,” Klein said, “so it will be important in the future to repeat this type of study in people who have type 2 diabetes.”
Source: Klein S, Magokos F, and Fraterrigo G, et al. Effects of moderate and subsequent progressive weight loss on metabolic function and adipose tissue biology in humans with obesity. Cell Metabolism. 2016.