The risks and benefits of weight loss drugs

It seems like weight loss drugs are constantly making the news these days – with some of it positive and some not so much.

On the plus side, the injectable medications are helping people lose a significant amount of weight, which has resulted in health gains for some. And a recently released study even indicated that the drugs can benefit your heart, too. The Select Trial indicated that Wegovy, the version of semaglutide that is marketed for weight loss, lowered by 20 percent the risk of strokes, heart attacks and other cardiovascular problems among overweight people with a history of heart disease.

On the negative side, news stories point to egregious side effects including nausea, vomiting and other gastric distress that some people experience while taking the popular weight loss drugs like Mounjaro, Wegovy and Ozempic (the version of semaglutide prescribed for type 2 diabetes).

We asked Miguel Prieto, MD, and internist with Cape Cod Healthcare’s Bourne Primary Care to share his thoughts on the possible benefits and risks of these weight loss drugs. Dr. Prieto said he has several patients who are currently taking these medications with great success and very few side effects.

“I’ve seen between 5 and 10 percent of the patients get side effects that are mostly transient, particularly nausea,” he said. “Some people get abdominal pain as well and it tends to happen mainly within the first 48 hours after the first dose. That tends to go away. Most of my patients do very well with this and they don’t have side effects unless we start getting into the higher doses, but it still is not that prevalent.”

For patients who do experience side effects, Dr. Prieto lowers the dose and that usually helps.

Part of the reason for his patients’ success is that Dr. Prieto carefully screens patients before prescribing the medications because certain populations are at much higher risk of side effects. Those include patients who suffer from pancreatitis, which is an inflammation of the pancreas, and patients who have a history of heavy alcohol use. The medications would be inappropriate for those patients, he said.

Unexpected Benefits

Interestingly enough, some of the side effects patients see are actually positive ones. The medications work by slowing down the digestion of food, but they also shut down the craving pathway in the brain. They clearly shut down the craving for food, but cravings for alcohol, cigarettes, gambling, drugs and compulsive shopping also go down significantly. That opens the possibility of future treatments with tweaked versions of the medications, he said.

Dr. Prieto has one patient with a very high BMI for whom he prescribed Mounjaro. The patient said that before taking the medication, his mind always revolved around food. Now that he is taking it, he doesn’t even think about food. He was at a meeting at work where someone brought in lasagna – his favorite food. He didn’t even have one piece.

Long-term Use

“My main concern with the shots is that they’re supposed to be used long term,” Dr. Prieto said. “And we don’t have studies that talk about using these medications for long term. We have the studies about using the medication for about 18 months or so but we haven’t seen studies about five years or ten years and what effect it will have on your gastrointestinal system.”

When patients go off the medications, they gain back 75 percent of the weight they lost within the first year, he said. With that in mind, he sees the medications as an opportunity not to cause transient weight loss, but as a way to help people make changes in their lifestyle that will make keeping the weight off a sustainable goal.

He offers the medication to patients who are willing to make lifestyle changes, rather than to patients who just want to rely on the shot and then continue to eat unhealthy processed or ultra-processed foods. He recommends that patients starting the medications make 20 to 30 percent changes in their diet by substituting nutritionally dense food for highly processed foods. Nutritionally dense foods are mostly plants, but people can have fish or chicken without the skin.

“If you start with 20 to 30 percent, it means that two or three out of ten meals will have to be absolutely made of non-processed foods,” Dr. Prieto said. “That enhances the effects of the medications in terms of weight loss. People lose between 15 and 17 percent of their body weight with Wegovy. With Mounjaro they can lose up to 23 or 24 percent of their body weight. It’s pretty significant.”

The beauty of Dr. Prieto’s advice is that it’s easier to make these lifestyle changes because the medications make the cravings go away. That means patients don’t feel deprived and are more likely to succeed. It also allows him to prescribe a lower dose, which translates to fewer side effects. Plus, once eating healthier becomes their new habit, it’s easier for them to continue, even after they stop taking the medication.

Type 2 Diabetes Benefits

Some of the most dramatic results Dr. Prieto has seen have been with patients with type 2 diabetes. The weight loss from a combination of the medication, along with a healthier lifestyle, has made it possible for him to taper the dose or even eliminate many of the other medications they take for metabolic disorders like high blood pressure and diabetes. One patient with type 2 diabetes was able to lower his A1C levels from 8.9 to 5.2.

“I was able to take that person off many of his diabetic medication,” he said. “It is very popular with patients when they are able to put their diabetes in remission.”

Even though there aren’t any studies yet that combine cardiovascular risk reduction with a whole food, plant-based diet, he is looking forward to seeing those studies in the future. Meanwhile, his experience with patients has confirmed his hypothesis.

“A lot of patients have decided to go to a whole food, plant-based diet after a very scary event like a heart attack or a stroke,” Dr. Prieto said. “Fear can become a really strong motivator, but if you add these medications and they make the lifestyle changes, which I’ve seen in a couple of patients, the effects are pretty dramatic. These medications are absolutely game changers.”