High cholesterol affects a wide range of people, and the risk factors go well beyond diet. About 1 in 200 people carry a genetic condition that elevates cholesterol from birth, while others develop it through a combination of age, medical conditions, medications, and lifestyle. Understanding which risk factors apply to you helps explain why your numbers may be elevated and what you can realistically do about it.
Family History and Genetics
The strongest single risk factor for high cholesterol is inherited. Familial hypercholesterolemia (FH) affects roughly 1 in 200 to 500 people worldwide, making it one of the most common genetic disorders. If you have it, your liver can’t clear LDL cholesterol from your blood efficiently, and your levels stay dangerously high regardless of how well you eat or how much you exercise.
The condition is caused by mutations in genes that control the LDL receptor pathway. Over 80% of genetically confirmed cases involve a mutation in the LDL receptor gene itself. Others involve mutations in a protein that acts as a docking signal for LDL particles, or in a protein called PCSK9 that controls how quickly LDL receptors are broken down. When any of these systems malfunction, LDL builds up in the bloodstream.
Certain populations carry FH at higher rates: Christian Lebanese, French Canadians in Quebec, Afrikaners in South Africa, and Ashkenazi Jews all have elevated prevalence. If a parent or sibling had very high cholesterol or a heart attack before age 55 (men) or 65 (women), FH is worth investigating. People with LDL levels at or above 190 mg/dL are generally treated aggressively because the risk of cardiovascular disease is so high.
Age and Hormonal Changes
Cholesterol levels rise naturally with age in both men and women. But the sharpest jump happens in women around menopause. Cross-sectional data from large population studies show that LDL cholesterol increases by roughly 15 to 25% around the time of menopause. That increase is larger than the gradual rise seen in men over the same age span, and it closely mirrors what happens in women who have their ovaries surgically removed. The connection is estrogen: it helps the liver clear LDL from the bloodstream, and when estrogen drops, LDL accumulates.
This means women who had healthy cholesterol numbers throughout their 30s and 40s can find themselves in the borderline or high range by their mid-50s without any change in diet or activity level. Men tend to see cholesterol climb more gradually, starting in their 20s and 30s, which is why screening is recommended for all adults starting at age 20.
Type 2 Diabetes and Insulin Resistance
If you have type 2 diabetes or prediabetes, your cholesterol profile is likely affected even if your total cholesterol number looks normal. Insulin resistance disrupts fat metabolism in several ways at once. Normally, insulin tells the liver to slow down production of triglyceride-rich particles and signals fat cells to stop releasing fatty acids into the bloodstream. When your cells stop responding to insulin properly, both of those brakes fail.
The result is a characteristic pattern sometimes called diabetic dyslipidemia: high triglycerides, low HDL (“good”) cholesterol, and a shift toward small, dense LDL particles that are more harmful to blood vessel walls than normal-sized LDL. Your LDL number on a standard blood test might not look alarming, but the particles themselves are more dangerous. This is one reason people with diabetes face elevated heart disease risk even when their cholesterol appears borderline.
Chronic Kidney Disease
Kidney problems and cholesterol are tightly linked. Dyslipidemia appears at every stage of chronic kidney disease, and the relationship goes both directions: abnormal cholesterol accelerates kidney damage, while declining kidney function further disrupts how the body processes fats. The kidneys play a role in breaking down and clearing certain lipoproteins, so as kidney function drops, triglycerides tend to rise and the overall lipid profile worsens. If you’ve been told your kidney function is reduced, lipid testing should be part of your routine monitoring.
Medications That Raise Cholesterol
Several common medications can push your cholesterol numbers up as a side effect. The most well-documented culprits include:
- Corticosteroids: At high doses, these increase fatty acid production in the liver and stimulate the release of fat from fat tissue, raising both LDL and triglycerides by variable amounts. Low doses tend to have minimal effects.
- Thiazide diuretics: Often prescribed for blood pressure, high-dose thiazides can raise LDL by about 10% and triglycerides by 5 to 15%.
- Loop diuretics: Similar to thiazides, these can raise LDL and triglycerides by 5 to 10%.
- Atypical antipsychotics: These are known to worsen lipid profiles, particularly triglycerides.
- Certain anticonvulsants and immunosuppressants: Both categories can negatively shift cholesterol levels.
If you started a new medication and your next blood test shows higher cholesterol, the drug may be a factor. That doesn’t necessarily mean you should stop taking it, but it’s worth discussing with your doctor whether the dose can be adjusted or whether the lipid changes need to be managed separately.
Diet and Saturated Fat
The American Heart Association recommends keeping saturated fat below 6% of your daily calories. On a 2,000-calorie diet, that works out to about 13 grams per day, roughly the amount in two tablespoons of butter plus a serving of cheese. Many people consume well above this threshold without realizing it, because saturated fat is concentrated in red meat, full-fat dairy, baked goods, and fried foods.
Replacing saturated fat with unsaturated fats from sources like olive oil, canola oil, nuts, and fish consistently lowers LDL. The effect isn’t dramatic for everyone, but for people whose cholesterol is driven primarily by diet rather than genetics, these swaps can move the needle meaningfully.
Physical Inactivity
A sedentary lifestyle lowers HDL cholesterol, which is the type that helps remove LDL from your bloodstream. Exercise reverses this. In one 16-week study, participants who progressed from 30-minute sessions three times a week to 45-minute sessions four times a week saw their HDL rise from 1.4 to 1.8 mmol/L (roughly 54 to 70 mg/dL), a clinically meaningful increase. Even 30 minutes of moderate exercise daily has been shown to boost HDL in people with diabetes.
Current physical activity guidelines recommend 150 to 300 minutes per week of moderate-intensity aerobic exercise, or 75 to 150 minutes of vigorous activity. You don’t need to hit those targets immediately. The improvements in HDL appear to scale with consistency rather than intensity, so regular walking or cycling counts.
Smoking
Smoking doesn’t just damage your lungs. It makes your existing LDL cholesterol more dangerous. Cigarette smoke is a source of free radicals that promote oxidation of LDL particles. Oxidized LDL is far more likely to embed in artery walls and trigger the inflammatory process that leads to plaque buildup. Research shows that nicotine specifically destabilizes LDL particles and increases the formation of harmful oxidation byproducts. Smokers also tend to have lower HDL levels, compounding the problem. Quitting reverses much of this damage over time, with HDL levels beginning to recover within weeks.
Ethnicity and Population Differences
Cholesterol risk isn’t distributed evenly across racial and ethnic groups, though the reasons are a mix of genetics, diet, and socioeconomic factors. Data from the Northern Manhattan Study found that Hispanic participants had the lowest average HDL cholesterol (43.9 mg/dL) and the highest triglyceride levels (146.5 mg/dL) compared to non-Hispanic Black and white participants. Non-Hispanic Black participants had the highest average HDL (52.3 mg/dL) but still had significant rates of elevated LDL. Non-Hispanic white and Hispanic participants were more likely to have LDL above 130 mg/dL.
South Asian populations, while not included in that particular study, are widely recognized as having elevated cardiovascular risk at lower cholesterol thresholds, partly due to higher rates of insulin resistance and a tendency toward smaller, denser LDL particles. If you belong to a higher-risk ethnic group, earlier and more frequent screening makes sense.
How These Risks Stack Up
Most people with high cholesterol don’t have just one risk factor. A 55-year-old woman going through menopause who also has prediabetes and takes a thiazide diuretic is being hit from three directions at once. A young man with a family history of FH who smokes faces compounding genetic and lifestyle risks. The value of knowing your specific risk factors is that some are modifiable and some aren’t. You can’t change your genetics or reverse menopause, but you can adjust your diet, increase your activity, and work with your doctor to evaluate whether a medication is contributing to the problem. Cholesterol management works best when it targets the actual drivers rather than relying on a single strategy.