If you’re trying to keep excess weight at bay, you might wonder whether hitting the gym or improving your meals makes the bigger difference. According to new research, the answer is simpler than you might think: do both.
A comprehensive seven-year study tracking nearly 7,300 British adults reveals that combining improved nutrition with increased physical activity proves more effective than focusing on either strategy alone.
Why the Combination Matters
Dr. Shayan Aryannezhad, who led the study while working at the University of Cambridge’s Medical Research Council (MRC), explained the findings: “We found that combining a better diet with more physical activity is an effective way to improve not just weight, but how much and where fat is stored in the body.”
There’s an important additional benefit to this dual approach, according to Aryannezhad, who now works as a clinical research fellow at the University of Oxford: “It’s particularly effective at reducing the build-up of harmful fat around organs.”
Not All Fat Loss Is Equal
The research team designed their study to examine which types of body fat respond best to different weight management strategies—an often-overlooked aspect of weight loss.
Aryannezhad explained in a Cambridge news release: “When people talk about changes in body weight, they often refer to a single number on the scale. But not all weight loss or gain is the same. First of all, we need to focus on fat mass when considering the risk of metabolic diseases like diabetes and heart disease. Second, body fat is stored in different places, and some types are more harmful than others. So, when we gain or lose weight, it matters where these changes happen.”
The study authors highlighted that visceral fat—the type that accumulates around internal organs—poses particular health risks. This dangerous fat has strong connections to type 2 diabetes, fatty liver disease, and cardiovascular conditions.
Study Details and Findings
Published on November 21 in JAMA Network Open, the research followed approximately 7,300 British participants who were an average of 49 years old at the study’s beginning. Over seven years, researchers monitored their dietary habits, physical activity levels, and body fat distribution.
Participants who focused solely on one improvement—either following the heart-healthy Mediterranean Diet more closely or increasing their daily exercise—did experience some protection against weight gain, including reduced fat accumulation both under the skin and around organs. However, these benefits were relatively modest when either approach was used alone.
The real breakthrough came from those who enhanced both their eating habits and activity levels simultaneously. This combined strategy delivered substantially better results.
By the study’s conclusion, people who adopted both lifestyle changes gained approximately 4 pounds less on average over the seven-year period compared to those who maintained their usual habits. Even more importantly, they accumulated roughly 150 grams (about 5 ounces) less visceral fat—the particularly harmful type that surrounds organs.
When researchers conducted deeper analysis, they discovered that the diet-and-exercise combination proved especially powerful at preventing visceral fat accumulation.
The Bigger Picture for Healthy Aging
Study senior author Nita Forouhi, who leads programs at MRC Epidemiology, emphasized the broader health implications in the news release: “Our research shows that improvements in diet with more physical activity in middle-age don’t just result in weight loss, but can potentially help prevent disease and support healthier aging. Despite the challenges of living in environments that promote unhealthy eating and inactivity, there is benefit from making small, sustained changes that lead to both healthier diets and increased energy expenditure.”
The takeaway is encouraging: you don’t need to choose between exercise and healthy eating. Making gradual, sustainable improvements in both areas can deliver meaningful health benefits that extend well beyond the number on your scale.