Multiple observational studies show that lower triglycerides are associated with higher HDL, and that lifestyle adjustments have the greatest influence on this. The evidence comes from observational research, however, not from randomised trials testing specific interventions for raising HDL. Moreover, recent research indicates that the quality of HDL is at least as important as the number, which nuances the simple 'the higher, the better' narrative.
HDL stands for high-density lipoprotein, commonly referred to as 'good cholesterol'. Large population studies have shown for decades that lower blood HDL levels are strongly associated with a higher risk of atherosclerosis and cardiovascular disease. The reverse also holds: higher HDL has traditionally been seen as protective. Yet it is not as simple as 'the higher, the better'. Research shows that even people with very high HDL sometimes develop coronary artery disease. This suggests that not only the quantity of HDL matters, but also how well it does its job: its function, particularly the removal of cholesterol from artery walls, is at least as important as the number on the lab report.
How much HDL you have is largely determined by genetics. Variations in the enzymes that build up or break down HDL explain a large share of the differences between individuals. This means that not everyone can raise their HDL equally through lifestyle changes. A rare inherited variant (V19L in the protein apoA-I) raises HDL and lowers the risk of coronary artery disease, but this is an immutable exception found in a small group of Icelanders. Chronic kidney disease is another example of a medical condition that disrupts HDL function, regardless of lifestyle.
The strongest lifestyle lever for HDL lies with triglycerides, the fats in the blood. High triglycerides generally go hand in hand with lower HDL: as triglycerides increase within HDL particles, their cholesterol content falls, and with chronically elevated triglycerides this mechanism becomes structurally disrupted. Even triglyceride values that are still just within the normal range are already associated with a higher risk of type 2 diabetes and an unfavourable HDL profile. Actively lowering triglycerides through lifestyle changes is therefore probably the most direct way to improve HDL as well.
In people with type 2 diabetes, being over the age of 65 appears to be associated with a greater likelihood of a normal HDL level, while being overweight (BMI above 25) and being female in that group are conversely associated with lower HDL. This suggests that metabolic disturbances such as insulin resistance and excess weight negatively affect the HDL profile, including in women, who generally have naturally higher HDL.
In practical terms, this means the following: lowering triglycerides through lifestyle changes, think less sugar and refined carbohydrates, less alcohol, more physical activity, and weight loss in those who are overweight, is the best-supported approach for both reducing triglycerides and improving HDL. The source texts do not mention any specific HDL-raising supplements or medications with proven effect. Anyone who has a chronic condition such as kidney disease or diabetes would be wise to discuss this with a doctor, because HDL function may be impaired in ways that lifestyle alone cannot resolve.
The claims are based on multiple human observational studies and population research. No RCTs or meta-analyses testing specific HDL-raising interventions are included in the sources. The associations are predominantly observational; causal statements about lifestyle interventions are therefore limited.