Heart health

Foods That Lower LDL Cholesterol: What the Research Actually Shows

LDL is the cholesterol number most people hear about at the doctor's office. It is the one that tends to be called "bad" cholesterol, and it is a main target when doctors talk about heart health.

If yours is higher than you would like, the internet will offer you a hundred miracle foods. The research is more modest, and more useful. Some foods do help. The size of the effect depends on which ones, and how many of them you eat together.

The biggest effect came from a team of foods

The Portfolio diet is a plant-based eating pattern built around four types of foods that are known to lower cholesterol:

• Nuts
• Plant protein (such as beans, lentils and soy foods)
• Viscous fiber, the kind that forms a gel (such as oats, barley and beans)
• Plant sterols, natural compounds found in plants and added to some fortified foods

A team of researchers pooled seven controlled trials of this pattern, with 439 adults who had high cholesterol. The people in those trials were already following a standard low-saturated-fat diet, and the Portfolio foods were added on top.

The result: LDL cholesterol dropped by about 17 percent (0.73 mmol/L, or roughly 28 mg/dL) compared with the standard diet alone. Total cholesterol, apolipoprotein B, triglycerides, blood pressure and C-reactive protein, a marker of inflammation, also improved. HDL cholesterol and body weight did not change. The researchers rated the certainty of the LDL result as high.

The lesson is not that you need to follow a strict plan. It is that stacking several cholesterol-friendly foods works better than relying on any one of them.

What nuts can do

A pooled analysis of 25 trials, with 583 adults, looked at nut consumption and blood fats. With an average of about 67 grams of nuts a day, which is roughly 2.4 ounces or a little more than two handfuls, people's LDL cholesterol fell by an average of 10.2 mg/dL, or 7.4 percent.

The effect rose with the amount of nuts, and different types of nuts worked about the same. People who started with higher LDL saw the biggest drops.

Nuts are calorie-dense. The easiest way to use them is to swap them in for a less helpful snack, not to add them on top of everything else you eat.

What oats and soluble fiber can do

Soluble fiber is the fiber that dissolves into a gel in your gut. It is found in oats, barley, beans, lentils, peas, nuts, seeds and some fruits and vegetables.

A meta-analysis of 67 controlled trials measured its effect. Every gram of soluble fiber, in the range of 2 to 10 grams a day, lowered LDL by about 0.057 mmol/L. That sounds like a lot until you do the math with real food:

That does not make oats a bad choice. It means oats are one piece of the puzzle, not the whole puzzle. They are a great place to start because they are cheap, easy and fit into breakfast.

The numbers side by side

These trials tested different groups of people and different amounts, so the rows are not a fair race. They show the size of the effect each time, not a ranking.

A simple day that uses all of it

You do not need the full Portfolio diet to use the idea. Here is one ordinary day that combines several of these foods:

• Breakfast: oatmeal with berries and a spoonful of chopped almonds.
• Lunch: a lentil or bean soup with a whole grain slice of bread.
• Snack: a small handful of walnuts or almonds instead of chips or cookies.
• Dinner: a stir fry with tofu or beans and plenty of vegetables.

Food labels can help too. The FDA lists saturated fat among the nutrients Americans should generally get less of, and the Daily Value for saturated fat is 20 grams a day based on a 2,000 calorie diet.

What to do with your doctor

Food is a good first step, and it is not the only one. Some people have cholesterol levels that are driven by genes, and diet alone may not be enough for them. If your doctor has recommended a medication, keep taking it as directed. Do not stop or change a medication because of something you read here.

A good conversation to have: ask your doctor what your LDL target is, and when to test again after you change your eating.

LDL cholesterol questions people ask

Sources

1. Chiavaroli L, Nishi SK, Khan TA, et al. Portfolio dietary pattern and cardiovascular disease: a systematic review and meta-analysis of controlled trials. Progress in Cardiovascular Diseases. 2018;61(1):43-53.
2. Sabate J, Oda K, Ros E. Nut consumption and blood lipid levels: a pooled analysis of 25 intervention trials. Archives of Internal Medicine. 2010;170(9):821-827.
3. Brown L, Rosner B, Willett WW, Sacks FM. Cholesterol-lowering effects of dietary fiber: a meta-analysis. American Journal of Clinical Nutrition. 1999;69(1):30-42.
4. MedlinePlus, National Library of Medicine. Fiber. Sources of soluble fiber.
5. U.S. Food and Drug Administration. Daily Value on the Nutrition and Supplement Facts Labels.

This guide is for general education. It is not medical advice and is not intended to diagnose, treat, cure or prevent any disease. Talk to your doctor or a registered dietitian before changing your diet, especially if you take medication or manage a health condition.