Being overweight isn’t linked only to heart risk (although it is that, too)–it’s connected to a constellation of factors that collectively increase a person’s risk for diabetes, cancer, stroke and even dementia. So losing weight is not by any stretch just about a single body system. Weight loss is important for almost every system–and a new study suggests that even for people who are obese, weight loss doesn’t have to be extreme to provide a person with some measurable health benefits. In fact, losing 5% of one’s body weight, the study finds, is linked to significant improvements in a number areas.
The new study assigned 40 obese participants to one of four weight loss conditions: They lost 5%, 10%, or 15% of their body weight by reducing their calorie intake. Participants in a control group were asked not to lose weight. The study period lasted for about three to 10 months, depending on the amount of weight lost. When the participants' weights were stable for three weeks after the weight loss, a number of metabolic, cardiac and inflammatory measures were logged.
At the beginning of the study, all participants had evidence of insulin resistance, a central feature of metabolic syndrome. After they lost the weight, people in the 5% group had improvements in the function of their pancreatic β cells, along with improvements in insulin sensitivity. They also had improvements in glucose levels, triglyceride (blood fat) levels, heart rate, systolic blood pressure and the hunger hormone leptin. The 5% weight loss did not affect cholesterol levels, either “good” or “bad” varieties.
"These results demonstrate you get a large bang for your buck with a 5% weight loss," said study author Samuel Klein. "Based on these findings, we should reconsider changing current obesity practice guidelines to stress a target goal of 5% weight loss, rather than 5% to 10% weight loss, which increases the perception of failure when patients do not achieve weight losses that are greater than 5%."
But with more weight loss came more improvements. And in a dose-depended manner: The more weight a person lost, the more their measurements improved. Losing 10% and 15% of body weight had increasing effects on all the measures mentioned above, with the addition of there being fewer markers of inflammation, including IL-6, the more weight the participants lost.
"Taken together, the findings show that 5% weight loss is sufficient to improve health outcomes, with additional weight loss further decreasing risk factors for metabolic and cardiovascular diseases," says Klein.
The team again suggests that the recommendation of losing 5-10% of one’s body weight, which certain health associations advise, may not be necessary. To start out, 5% may be enough. And to a 200-pound person who wants to lose weight, hearing that it’s okay to start with just 10 pounds, rather than 20, may make a big difference, psychologically.
Of course, losing more weight may be better. But just the idea that less is just fine, too, at least to start, may be just what we need to hear.