Wegovy in Men vs. Women: Study Shows How Weight Loss Differs

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Key Takeaways

• New research found that women with a certain type of heart failure lost more weight on Wegovy than men with the same condition.

• On average, the women in the study lost 2.5% more weight than the men.

• Experts said there are a few reasons why this may have happened, and it doesn’t mean that weight loss drugs aren’t as effective for men.

A new study showed that Wegovy (semaglutide) may be more effective for weight loss in women who have a type of heart failure known as heart failure with preserved ejection fraction (HFpEF) compared to their male counterparts.

The medication, a type of GLP-1 receptor agonist, was initially approved for chronic weight management in 2021. Earlier this year, the indication was extended to reduce the risk of heart attack, stroke, and other cardiovascular problems in adults with heart disease who have obesity or overweight.

Experts say there are a few reasons why this may have happened, and it doesn’t necessarily mean that this medication doesn’t work as well for men. In fact, men may just need a higher dose.

What Is Heart Failure?

Heart failure is a lifelong condition in which the heart muscle can’t pump enough blood to meet the body’s needs for blood and oxygen. The type of heart failure a person has is based on a measure called ejection fraction, which is the amount of blood pumped out of the left ventricle with each contraction of the heart.

Heart failure with preserved ejection fraction (HFpEF) is also called diastolic heart failure. Patients with HFpEF have a heart muscle that can pump normally but struggles to relax and fill with blood properly. Symptoms of HFpEF can include fatigue, weakness, shortness of breath, trouble exercising, weight gain, loss of appetite, or cough.

The study included data from 1,145 patients with HFpEF who were randomized to either get a weekly injection of semaglutide 2.4 mg (which is the higher dose of Wegovy) or a placebo for 52 weeks. Of the study participants, 570 were women.

The researchers also looked at some specific details about the participants. They noted that the women had higher body mass index (BMI) and worse heart failure symptoms at the start of the study compared to the men. While both men and women saw their symptoms get better when they were taking Wegovy during the study, the women lost more weight (about 9.6% of their original weight) than men (who lost about 7.2% of their body weight).

While the women lost about 2.4% more weight than men during the entire study, participants of both sexes noticed improvements in measures of heart health. Those findings align with other research that suggests the benefits of drugs like Wegovy may go beyond weight loss.

A Note on Gender and Sex Terminology

In research, terms like “men” and “women” usually refer to how the participants are grouped by sex, not necessarily gender identity. In this study, the authors noted that a limitation of their research was that their “analyses were confined to biologic sex and the impact of gender was not characterized.”

Why Women Lose More Weight Than Men

The study did not explore why women seemed to lose more weight than men. However, experts have a few theories, one of which relates to men and women having different distributions of body fat.

“The men had a greater amount of belly fat as seen with their greater waist circumference, and the women a greater amount of hip and thigh fat as manifest by their greater BMI despite smaller waists,” Richard Wright, MD, a cardiologist at Providence Saint John’s Health Center in Santa Monica, CA, told Verywell. The different distribution of fat is also involved in the various metabolic and endocrine changes that happen with obesity.

Another body composition element is that men tend to have more lean muscle mass than women. “If you’re preserving the muscle and just losing fat, women might lose a little bit more. They typically have more fat mass to lose,” Mir Ali, MD, medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, told Verywell.

The men were also much larger than the women—both in height and baseline weight.

“It is plausible that the men would have responded equivalently to women if only they were administered a higher dose of semaglutide,” said Wright.

Under normal circumstances (e.g., in the real world and not in a research setting), the medication’s dose would have been adjusted to help patients achieve a targeted amount of weight loss.

“Had that design been undertaken in this study, it is plausible that the achieved weight loss would have been similar between the sexes,” added Wright.

As the study’s authors pointed out, women have smaller hearts than men—even when their heights and weights are comparable. As a result, they usually have less circulating blood volume.

“The physiologic changes in heart failure may be subtly different between men and women, and doses of medications may differ by sex as well,” said Wright.

Related: Healthy at Every Size? Here's What Doctors Look for Beyond BMI

Is There a Better Weight Loss Drug for Men?

Weight loss medications aren’t one size fits all. Some people do better with one over another, Dina Peralta-Reich, MD, the director of New York Weight Wellness Medicine, told Verywell.

“The first thing is to address if the patient is on the right dosing,” said Peralta-Reich. “With semaglutide, you have the initiation dose that you keep increasing until you reach the optimum weight loss dose,” said Peralta-Reich. From there, providers will often look at what patients eat to make sure they’re including enough foods that provide protein and other key nutrients needed to support weight loss and help maintain muscle.

But sometimes, a medication just isn’t a good fit for a patient. “Some types of obesity are not going to respond well to semaglutide,” added Peralta-Reich.

If you have HFpEF and want to lose weight and are thinking about trying medication, Ali recommends talking to a provider about all your options. For example, another medication like Zepbound (tirzepatide) may be a better fit for you, or surgery might be an option.

What This Means For You

If you have HFpEF and are interested in losing weight, talk to your provider about your options. They may recommend trying a medication like Wegovy or an approach like bariatric surgery.

Read Next: GLP-1 Drugs Won't Fix the Flaws in Obesity Care

Read the original article on Verywell Health.