If you're an adult with high 'good' cholesterol (HDL), especially when your 'bad' cholesterol and triglycerides are low, you're about 40% less likely to have heart disease compared to people with low good cholesterol — it seems high good cholesterol helps protect your heart when the rest of your lipid profile is healthy.

What we've found so far suggests that higher levels of HDL cholesterol, often called "good" cholesterol, may be linked to a lower likelihood of heart disease when LDL cholesterol and triglycerides are low. Our analysis of the available evidence shows this pattern clearly in the data we’ve reviewed. We analyzed 53.0 studies or assertions that support the idea that high HDL cholesterol is protective against heart disease in adults who also have low LDL cholesterol and triglycerides [1]. In these cases, people with higher HDL levels were about 40% less likely to develop heart disease compared to those with lower HDL levels [1]. No studies in our review refuted this idea. The evidence we’ve reviewed leans toward the view that a healthy overall lipid profile — high HDL, low LDL, and low triglycerides — is associated with lower heart disease risk. However, we only reviewed one distinct assertion, even though it was supported by 53.0 studies. This means our current analysis is based on a narrow set of claims, and we cannot say whether other factors might change this picture. We don’t yet know if raising HDL cholesterol alone would lead to this same benefit, or if the protection comes from the combination of healthy lipid levels working together. Our current analysis does not include evidence on whether interventions to raise HDL would reduce heart disease risk, only that high HDL is linked to lower risk when other lipids are already in a healthy range. Practical takeaway: If your LDL and triglycerides are low, having high HDL might be a positive sign for heart health — but we don’t yet have enough evidence to say that boosting HDL alone will help.