High cholesterol: what your numbers mean, and how to lower them with food

What is high cholesterol?

Cholesterol travels through the blood in particles called lipoproteins. LDL (low-density lipoprotein) carries cholesterol into artery walls, where it builds into plaque. Decades of genetic, population and clinical-trial evidence show that LDL is a cause of heart disease, not just a marker of it: the lower your LDL over your lifetime, the lower your risk. Triglycerides are the main fat in the blood; high levels usually travel with insulin resistance, excess weight, added sugar and alcohol. HDL is the "good" cholesterol; low HDL is one of the signs of metabolic syndrome.

High cholesterol has no symptoms. The only way to know is a blood test (a lipid panel).

What your numbers mean

Ranges from the National Cholesterol Education Program (ATP III). If you have heart disease, diabetes or other risk factors, your doctor may set lower targets.

Why "otherwise healthy" doesn’t cancel high LDL

A study of lean, metabolically fit people on very-low-carb diets whose LDL rose sharply found that those with the highest LDL still showed faster plaque progression. Good blood sugar, a healthy weight or a fit body don’t make high LDL safe.

How to lower LDL with nutrition

1. Swap saturated fat for unsaturated fat

Saturated fat (fatty meats, butter, cheese, full-fat dairy, coconut and palm oil) raises LDL by reducing how much the liver clears from the blood. Replacing it with unsaturated fat lowers LDL and cardiovascular events. In practice: cook with olive oil instead of butter, choose lean cuts and more fish, go easier on cheese, and lean on nuts, seeds and avocado. If you need to lower LDL, the American Heart Association suggests keeping saturated fat to 5–6% of calories (about 11–13 g on a 2,000-calorie day).

2. Add soluble fiber every day

Soluble fiber binds bile acids in the gut; the liver then pulls cholesterol out of the blood to make more. 5–10 g a day of soluble fiber lowers LDL by about 5%. Good sources: oats, barley, beans, lentils, apples, pears and Brussels sprouts. A psyllium husk supplement lowered LDL by about 11 mg/dL on average in trials, with 7–10 g a day used for cholesterol (see Psyllium Husk for Fat Loss).

3. Consider plant sterols and stanols

About 2 g a day of plant sterols or stanols, from fortified foods or supplements, lowers LDL by roughly 7–10%, and the effect adds to diet changes and to statins.

4. Lose excess weight, if you have it

Weight loss lowers LDL by roughly 1.3 mg/dL per kilogram lost, so about 13 mg/dL for 22 lb. That’s helpful but modest; it has a bigger effect on triglycerides, and it improves blood pressure, blood sugar and liver fat at the same time.

Lowering triglycerides

• Lose excess weight, especially abdominal fat.
• Cut back on added sugar and refined carbohydrates, sugary drinks first.
• Limit alcohol, which raises triglycerides directly.
• Eat fatty fish (salmon, sardines, mackerel) a couple of times a week.

When diet isn’t enough

Genetics play a large role in cholesterol. Familial hypercholesterolemia, for example, keeps LDL high regardless of diet and is often undiagnosed. If your LDL stays high despite real changes, medication such as a statin may be medically necessary. That’s not a failure: diet stays the foundation and makes medication work better. Never stop or change a medication without your doctor.