If an adult has both low 'good' cholesterol and high triglycerides, their heart disease risk goes up more than if they just had low good cholesterol — it's like the high triglycerides make the low good cholesterol risk worse.

What we've found so far is that having low HDL (the “good” cholesterol) along with high LDL (the “bad” cholesterol) and high triglycerides appears to be linked to a greater risk of heart disease than having low HDL alone. The evidence we've reviewed leans strongly in this direction. Our analysis of the available research shows that when low HDL occurs together with high triglycerides, it seems to make the heart disease risk worse than if low HDL were the only issue [1]. This pattern was supported by 53.0 studies or assertions. We also found that when high LDL is added into the mix—so all three are present: low HDL, high LDL, and high triglycerides—the risk appears to be even higher compared to having just low HDL by itself [2]. Another 53.0 studies or assertions support this broader combination effect. No studies in our analysis refuted these patterns. That means all 106.0 supporting assertions point toward a stronger link between this combination of blood lipid levels and increased heart disease risk. We don’t yet know the exact size of the increase or how these factors interact over time, but what we can say is that the evidence consistently suggests the combination is more concerning than low HDL alone. We recognize that this is a partial picture. Our current analysis doesn’t include data on other factors like diet, exercise, or genetics, which may also play important roles. As we gather more evidence, our understanding may evolve. Practical takeaway: If you have low HDL along with high LDL and high triglycerides, the evidence we’ve reviewed suggests this combination may pose a greater concern for heart health than low HDL by itself.