Can weight loss injections relieve back and joint pain?

Weight loss injections (like Wegovy and Zepbound) can help you to lose weight when used alongside a healthy diet and regular exercise. Wegovy contains the active ingredient semaglutide, which is a type of medication known as a GLP-1 receptor agonist. Zepbound uses a similar (but slightly different) active ingredient called tirzepatide, which works as a GIP receptor agonist as well as a GLP-1 receptor agonist.

This means the two injections work in really similar ways. The GLP-1 receptor agonist in both medications mimics the natural GLP-1 hormone your body produces after you eat. This hormone tells your body to release insulin when your blood sugar levels are high, and slows down how quickly food passes through your stomach after eating. It also affects signals in your brain to suppress your appetite, increase how satisfied you feel after eating, and reduce food cravings in between meals. This should help you to build healthier eating habits and lower your overall calorie intake to help you lose weight.

Zepbound also works as a GIP receptor agonist alongside a GLP-1 receptor agonist. GIP receptor agonists are thought to help with weight loss by increasing feelings of satiety, to help you eat less. This combination of a GLP-1 and GIP receptor agonists has been shown to be more effective for weight loss than GLP-1 receptor agonists alone – which makes Zepbound a more effective weight loss treatment than Wegovy. One study comparing semaglutide to tirzepatide for weight loss in people with type 2 diabetes found that, on average, tirzepatide helped people lose 17.8% of their body weight, compared with 12.4% for semaglutide.

But will losing weight with weight loss injections actually help reduce back and joint pain? When it comes to joint pain, the scientific evidence is really positive. One study found that, for women of average height, every 11 lbs of weight lost reduced the risk of developing knee osteoarthritis by more than half. The study also found that if men with obesity lost enough weight to move to overweight, and men in the overweight category lost enough weight that they were no longer living with overweight, the risk of knee osteoarthritis would decrease by around 21.5%.

There’s less evidence that losing weight will help with back pain when compared with joint pain, however. It’s thought that losing weight with diet and exercise could take pressure off your vertebrae, strengthen your core and back muscles to help support your spine, and improve your mobility to help with your quality of life. But the available evidence is currently very limited.

A review of relevant research identified eleven studies looking into the relationship between weight loss and back pain, only one of which was a randomized controlled trial. In this trial, 160 people were randomly assigned to either a 6-month telephone-based healthy lifestyle coaching service or a waiting list for 26 weeks. The study found that this lifestyle intervention did not help improve pain or quality of life in people with lower back pain and overweight or obesity. More high quality studies are needed to determine whether or not weight loss could improve pain and quality of life in people living with chronic back pain.