People with higher insulin resistance—measured by a specific blood test—are much more likely to have heart problems or die from any cause, even if they’ve never had heart disease before.

Even if you exercise a lot and meet the recommended activity guidelines, having very bad insulin resistance can still make you more likely to die from any cause — meaning exercise alone isn’t enough to completely protect you from serious metabolic problems.

People with heart disease who have higher levels of both triglycerides and blood sugar are about 30% more likely to have a heart attack than those with lower levels, even after accounting for other health factors.

People with heart disease who have higher levels of triglycerides and blood sugar together are a bit more likely to have another serious heart problem, like a heart attack or stroke, than those with lower levels.

If someone with heart disease has their bad cholesterol (LDL) well controlled under 100, then their triglyceride and sugar levels (TyG) don’t seem to add much extra risk for heart problems.

Even if someone doesn’t have full metabolic syndrome, having high insulin resistance (a sign their body doesn’t respond well to insulin) still raises their risk of heart attacks and strokes by about 50%.