Metformin cancels out the diabetic benefits of exercise

Medications for type 2 diabetes are intended to control the condition, not cure it. That doesn’t mean the condition can’t be managed, even reversed, without medication for many people…

Previous studies have shown that a very low-calorie diet for 8 weeks can reverse diabetes, and that losing 10% of body weight within five years of diagnosis can send it into remission.

Then there’s exercise…

According to the American Diabetes Association, simply walking after a meal has a powerful effect on lowering blood sugar levels. Ramp it up and, in one study I read, high-intensity exercise improved blood glucose levels for up to three days.

That’s why most doctors who prescribe the most popular drug for type 2 diabetes — metformin — also recommend that their patients exercise. Sounds like a perfect strategy, right?

Except for one problem…

Metformin appears to undo all the gains of exercise — and not just in terms of diabetes.

Exercise powers whole body health except when you take metformin

Although most doctors recommend metformin plus exercise as their most trusted strategy for preventing metabolic disease, Rutgers researchers say the math doesn’t add up.

“Most health care providers assume one plus one equals two,” said Steven Malin, a professor in the Department of Kinesiology and Health in the School of Arts and Sciences and the lead author of the study. “The problem is that most evidence shows metformin blunts exercise benefits.”

The Rutgers researchers decided to test the theory by monitoring 72 adults at risk for metabolic syndrome who engaged in both high-intensity and low-intensity exercise for 16 weeks, while also taking either metformin or a placebo.

The results were clear…

Exercise alone resulted in improvements in:

• Vascular insulin sensitivity – Blood vessels responded better to insulin, allowing more blood flow to muscles. Better blood flow helps shuttle glucose from the bloodstream into tissues, resulting in lower blood sugar levels after meals.
• Fasting glucose – Fasting glucose is your blood sugar level between meals, when it should be at its lowest. High levels can indicate insulin resistance and increase your risk of serious health issues
• Aerobic fitness – Fitness gains translate into energy for daily life. This includes activities such as climbing stairs and staying active with friends. If those improvements stall, your quality of life suffers.
• Inflammation – Because inflammation is now often termed ‘the root of all disease’, lowering inflammation levels is vital to improving your health for life.
• Blood vessel function – Improving blood vessel function through exercise is crucial for maintaining cardiovascular health, as it enhances blood flow, lowers blood pressure and reduces your risk of heart disease.

In other words, exercise works like a ‘super-pill’ for your health, improving your blood sugar and blood flow, fighting off disease-causing inflammation and leveling up your fitness to enhance your daily life.

But add metformin to the mix and those benefits may just go right down the drain…

Metformin: generating a long-term health risk

The research showed that taking metformin while exercising blocked improvements in all categories.

“Blood vessel function improved with exercise training, regardless of intensity,” Malin said. “Metformin blunted that observation, suggesting one type of exercise intensity is not better either with the drug for blood vessel health.”

This matters because exercise is intended to lower blood sugar and improve physical function, which are crucial goals of diabetes treatment. If metformin interferes with those benefits, patients may not get the protection they expect.

“If you exercise and take metformin and your blood glucose does not go down, that’s a problem,” Malin points out. “People taking metformin also didn’t gain fitness. That means their physical function isn’t getting better and that could have long-term health risk.”

Blood sugar management with exercise

If you’re living with type 2 diabetes, it might be time to talk to your doctor about whether taking metformin could be keeping you from experiencing the benefits exercise can deliver, not only for your blood sugar, but your whole body.

However, never stop taking any medication without having that discussion with your prescribing doctor.

Other options would work quite well with exercise, including the ‘diabetes spice’ that was shown to beat metformin by inducing anti-diabetic activity.

Specifically, it has been shown to reduce appetite, glucose absorption in the intestines, body weight, and lower blood glucose, cholesterol and triglyceride levels. It also helps stimulate the secretion of insulin from beta-cells in the pancreas.

Research has even found that it helps improve glucose tolerance as efficiently as metformin, while showing no significant adverse effects.

Along with the right diet that limits sugary foods and drinks, refined grains, processed meats and unhealthy fats, that’s a great setup.

I don’t think there is anything more counterintuitive than knowing that a medication can undo the benefits associated with a healthy lifestyle habit, such as exercise.

Sources:

Blood sugar regulation as a key focus for cardiovascular health promotion and prevention: an umbrella review — NIH

The extra life-saving benefits of exercise for diabetics — Easy Health Options

Metformin Side Effects — Drugs.com

Exercise and your arteries — Harvard Health

Why your daily walk might not work as well if you’re on metformin — EurekAlert!