For some people with type 2 diabetes who are overweight, losing weight through diet and exercise can lower their chance of having a heart attack or stroke—but for others, it might actually increase that risk.

Losing weight with diet and exercise doesn’t always help the heart in people with type 2 diabetes—sometimes it helps a lot, sometimes it doesn’t help at all, and sometimes it might even make things worse.

For people with type 2 diabetes, factors like age, weight, blood sugar levels, and past heart problems can tell us whether losing weight through diet and exercise will help or hurt their heart health.

If you’re overweight (BMI 23 or higher), having type 2 diabetes explains about a quarter of why you’re more likely to have heart problems — meaning diabetes is a big reason why extra weight hurts your heart.

Making lasting changes to how you eat and move can help stop prediabetes from turning into full-blown diabetes—but in real life, most people struggle to stick with these changes, so they don’t work as well as they do in fancy research studies.

People with type 2 diabetes who eat less healthy foods are more likely to be overweight or have high blood sugar than those who eat healthier.