For people who carry extra pounds, a healthy diet may help ease chronic aches and pain—even if the number on the bathroom scale doesn’t change, a recent study suggests.

It’s long been known that excess weight, particularly obesity, can put stress on the joints and contribute to chronic pain. Because of that, doctors routinely recommend weight loss for people who are obese or overweight and have painful conditions such as knee or hip osteoarthritis.

But the recent findings, published in the European Journal of Nutrition, suggest that a healthy diet, on its own, might bring pain relief to some people. That’s good news, considering how tough it can be to shed excess pounds and keep them off.

Healthier foods, less pain

For the study, researchers in Australia recruited 104 adults ages 25 to 65 who were in the overweight-to-obese range (none had severe levels of obesity). The participants followed a three-month diet aimed at helping them shed one or two pounds per week, with each individual receiving a personalized calorie-cutting goal. They also underwent health evaluations and kept a four-day record of their eating habits (which yielded a diet-quality score) at the beginning and end of the study period.

Overall, the participants did lose weight on the diet (about 14 pounds, on average). They also showed a substantial change in pain complaints: At the outset, half of them suffered from chronic pain—mostly affecting the neck, back, or lower limbs. By the three-month mark, that number had dropped by half, to 24 percent.

Interestingly, though, there was no correlation between weight loss and the likelihood of reporting pain relief; that is, weight loss didn’t explain the benefit some people felt. Instead, diet quality seemed to be key. On average, participants bumped up their diet-quality scores by 22 percent during the course of the study. And unlike weight loss, improved diet quality did correlate with higher likelihood of pain relief.

It’s not clear why a high-quality diet might ease bodily pain. One possibility, based on previous research, is that healthier eating helps reduce chronic low-level inflammation in the body. However, the investigators on this study did not analyze participants’ blood samples for changes in inflammatory markers (specific proteins that indicate ongoing inflammation). That might have given clues as to the “why.” 

Defining “quality”

As for what constitutes a higher-quality diet, the study used tried-and-true measures. Participants improved their diet scores by boosting their intake of fruits and vegetables, nuts, and fiber-rich whole grains, and choosing lean cuts of meat or meat alternatives (beans or bean products like tofu, for instance). Diet quality was also gauged by what people left out, whether partly or completely—including red and processed meats and packaged foods full of added sugar, fat, and salt.

The traditional Mediterranean diet, the DASH eating plan, and the Flexitarian Diet are good examples of high-quality eating. While some specifics differ, all of these diets encourage people to get plenty of plant-based foods and healthy fats from sources like nuts, olive oil, and oily fish, while limiting sugar, salt, and animal products high in saturated fat. The primary goal is not weight loss, but improving health by making sustainable diet changes for the better (though weight loss can happen, too).

The caveats

It’s important to stress that the study’s findings do not prove that healthy foods per se act as analgesia. The study only shows a correlation between improved diet quality and pain relief. The researchers point to one alternative explanation: Study participants might have felt empowered by revamping their diets, which changed their perceptions of their pain. However, even if that was the mechanism, the end result—less pain—is what matters.

There are other limitations to the study, one being the population included. Participants were 48 years old, on average, and they typically rated their pain as mild to moderate at the outset. It’s not clear whether the results would be the same for older adults or for people with more debilitating pain. In addition, the study period was short—only three months—so we do not know whether the pain reduction holds up over time. Finally, this study was a secondary analysis of a trial that was designed to test the effects of two reduced-calorie diets on weight loss; in other words, the trial was not set up to study pain relief specifically, which lessens the strength of its findings.

The takeaway: Despite the study’s shortcomings, it’s hard to argue against healthier eating. We know that diets like those described above are tied to lower risks of major medical conditions like type 2 diabetes, heart attack, stroke, certain cancers, and even possibly Alzheimer’s disease. The new findings suggest that, at least for some people, healthy eating might bring the more immediate benefit of ameliorating chronic aches and pains as well.