How to lower cholesterol
Dietary cholesterol may not be as bad for your health as was once thought, but prudent food choices are still advised — along with other lifestyle changes — to lower high blood cholesterol.
The jury is still out about the effects of different food groups — including saturated fats, high-fat dairy products, and omega-3 fatty acids — on your blood cholesterol. Back in the 1960s, scientists concluded that eating a lot of cholesterol clogs your arteries and increases your risk of heart disease. As a result of this hypothesis, the American Heart Association began adopting recommendations that people limit their dietary cholesterol to 300 mg a day. Eggs, meat, and dairy were demonized. However, beginning in 2015, the Dietary Guidelines for Americans dropped its recommendations for daily cholesterol limits. So, what happened? Shouldn’t we all try to eat less cholesterol? And are there any classes of foods that can help you lower your cholesterol? We will explore these and other questions.
What is cholesterol?
It turns out that lipoproteins — which carry cholesterol in the bloodstream — are what medical providers worry about when assessing your cholesterol profile. Low-density lipoprotein (LDL) cholesterol is sometimes called “bad cholesterol,” while high-density lipoprotein (HDL) cholesterol is called “good cholesterol.” If there is too much LDL cholesterol in your blood, it can attach to the walls of the blood vessels and form plaques that may reduce blood flow — increasing your risk of heart attacks and strokes. Furthermore, studies also show that your risk of heart disease increases as these lipoprotein particles get smaller and smaller.
Although cholesterol has gotten a bad reputation, we actually need cholesterol to function. It helps build healthy cell membranes and is essential for making vitamin D, hormones, and fat-dissolving bile acids. It’s only when cholesterol levels are too high that problems occur. Most cholesterol in your body is made by your liver; the rest comes from your diet. That’s one reason why traditional approaches to reduce cholesterol have been diet-based.
Is dietary cholesterol bad for you?
It might seem obvious that your blood cholesterol would get higher when you eat foods that are high in cholesterol, but as the conflicting studies around high cholesterol foods show, it doesn’t necessarily work like that. In fact, your body tends to maintain constant cholesterol levels regardless of what you eat.
There is a growing consensus that, for most people, the amount of dietary cholesterol does not affect blood cholesterol very much at all. Of course, there is a minority of people — about one-quarter of the population — who are more sensitive to dietary cholesterol, probably due to genetic reasons. So, what happens when these people eat foods that are high in cholesterol? Although LDL increases moderately in these individuals, their risk of heart disease actually remains unaffected.
It is also important to point out that a lot of food experts are beginning to move away from daily recommendations that are based on entire food groups. The view is starting to emerge that foods are just too complicated to classify in that manner. As a 2020 study stated, “The health effects of foods cannot be predicted by their content in any nutrient group without considering the overall macronutrient distribution.”
Putting aside this more nuanced medical view of the actual physiological impact of food consumption, there are still certain foods that are high in dietary cholesterol that could negatively affect blood cholesterol, and if they don’t confer any offsetting nutritional value, individuals might consider reducing their consumption of them, as we discuss in the next section.
What foods are high in cholesterol?
Dietary fats: Trans and saturated fats
It has long been recognized that “bad fats” — trans-fatty acids and saturated fatty acids — are detrimental, increasing your risk for heart disease — partly due to their effects on blood cholesterol. Trans-fatty acids are seen as particularly bad, regarded as the worst dietary fatty acid per gram because of their role in coronary heart disease. Studies have linked consumption of trans fats to heart disease, inflammation, higher LDL cholesterol, and lower HDL cholesterol. These fatty acids are found primarily in processed snacks, baked goods, partially hydrogenated vegetable oils and foods containing these oils, and in ruminant (animal) fats.
Saturated fatty acids (SFAs), which are found in animal-based foods (such as beef, pork, poultry, full-fat dairy products, and tropical oils), have also been vilified for causing high cholesterol and heart attacks. However, the narrative here, as well, has shifted over the past decade. Although guidelines from the American Heart Association still have a negative view of saturated fats and recommend that you limit their consumption to only 13 grams per day, recent literature reviews have a somewhat more positive view of SFAs:
- A 2020 review in the Journal of Cardiology reported that several foods relatively rich in SFAs — such as whole-fat dairy, eggs, dark chocolate, and unprocessed meat — are not associated with increased cardiovascular disease or diabetes risk, and the review authors even argued that SFAs may have protective effects against strokes.
- While saturated fats tend to increase your LDL (“bad”) cholesterol, this increase in LDL appears, with some foods, to be due to larger LDL particles that are not linked to cardiovascular disease.
Parenthetically, what has clearly come to the forefront of medical advice on fats is that there are healthy kinds — primarily monounsaturated (e.g., olive oil) and polyunsaturated (e.g., nuts and seeds) fats — that should be a part of any healthy diet — assuming they are consumed in moderation so as to avoid weight gain relating to their high-calorie profile.
The special case of high-fat dairy products
In the 1980s, many dietary guidelines warned against high-fat dairy products due to observations published in 1979 about the correlation between dairy fat consumption and coronary heart disease. But as in the case of certain types of non-dairy foods that contain saturated fats, the narrative around dairy appears to be shifting somewhat. Although guidelines still recommend that most full-fat dairy products be avoided and replaced with low-fat or no-fat versions, recent scientific research suggests they many full-fat dairy products might not be as bad for you as was suggested some 30+ years ago:
- A 2018 study concluded that whole milk might actually be good for you by increasing HDL. The same study found no impact of whole milk on total cholesterol, LDL cholesterol, insulin, or blood glucose concentrations. The authors suggest that whole milk might be even considered a part of a healthy diet among people with normal cholesterol levels.
- Researchers have also reported that dairy fatty acids might actually have a protective effect — albeit a small one — against type 2 diabetes, which researchers suggested is due to medium-chain unsaturated fatty acids.
- In the case of eggs, people with high cholesterol are still sometimes discouraged from eating too many of them each week because a single large egg can contain up to 190 mg of cholesterol. But while a 2020 meta-analysis did conclude that egg consumption is associated with higher LDL and LDL/HDL ratios, epidemiological studies have found only weak associations between the intake of eggs and cardiovascular disease. How is this possible? For one thing, only about 1.5 grams of the fat in a typical egg is saturated fat, whereas 3.5 grams are a combo of poly- and monounsaturated fats. Plus, it turns out that egg consumption shifts LDL particles toward larger sizes and often increases HDL. Eggs also contain important nutrients like high-quality proteins, vitamins, minerals, and phospholipids.
- Even leading medical institutions such as the Cleveland Clinic, while continuing to recommend diets favoring low-fat over high-fat dairy, question the long-held belief that whole milk is bad for you, citing its importance in preventing bone loss.
What foods help lower cholesterol?
Although the evidence remains inconsistent regarding foods formerly believed to increase cholesterol, studies do suggest that several foods can help lower cholesterol:
- Several studies have linked consumption of omega-3 fatty acids, found in fatty fish, and nuts, to decreased triglyceride levels and blood pressure. However, other studies have reported no benefits associated with omega-3 consumption, and some have even reported that they can decrease HDL.
- Various studies have suggested that avocados; legumes; nuts; soy foods; plant sterols and stanols; and fruits and vegetables are all helpful in lowering cholesterol.
- A 2016 review concluded that soluble fiber reduces LDL cholesterol. Soluble fiber is found in foods such as kidney beans, Brussels sprouts, apples, and pears. Another great source of soluble fiber is oatmeal, which is often recommended for people who struggle with high blood sugar.
The importance of healthier lifestyle choices
While fish, avocadoes, almonds, and oatmeal are worth a try, lifestyle changes may be a better way to reduce your cholesterol. The 2022 ACC/AHA Lipid Guidelines stress the importance of personalized care and lifestyle interventions. The guidelines highlight the consequences of unhealthy eating, cigarette smoking, sedentary habits, and obesity.
- Weight loss. Several studies show that modest weight loss (5 to 10%) can lower cholesterol and reduce your risk of heart disease. A 1992 review concluded that weight loss through caloric restriction is a good way to reduce cholesterol in people who are overweight. A 1999 study demonstrated a decline in circulating lipid concentrations in obese men who lost moderate amounts of weight. A 2011 review further documented that even modest weight loss is associated with increases in HDL (“good”) cholesterol in overweight people with type 2 diabetes.
- Exercise. Exercise appears to be another great strategy for lowering cholesterol. A 2016 study found that aerobic exercise improved the cholesterol profile of postmenopausal women. A 2013 study found that aerobic exercise led to decreases in total cholesterol and increases in HDL (“good”) cholesterol in women with metabolic abnormalities. A 2013 study on middle-aged overweight men further demonstrated that high-intensity circuit training had positive impacts on both LDL and HDL cholesterol levels.
- Tobacco avoidance. Major medical organizations, including the Cleveland Clinic, recommend that you quit any tobacco use. Among other adverse effects, cigarette smoking is thought to increase the oxidation of LDL cholesterol.
- Medication. There are several pharmacological options aimed at lowering blood cholesterol, such as statins, that your doctor might recommend for you. But statins can have side effects and may increase your risk for new-onset diabetes. Medications should only be taken under the guidance of your medical provider.
Key takeaways
There is a growing consensus among the scientific community that dietary cholesterol does not have as much of an effect on blood cholesterol as was previously thought. Nevertheless, most major medical organizations continue to advise avoiding or moderating your consumption of certain high-cholesterol foods, some of which can increase your risk of cardiometabolic disorders or other conditions. Fortunately, there are a number of foods that may help to lower your cholesterol. As or more importantly, medical providers advise that weight loss, exercise, and avoiding tobacco are great lifestyle approaches for reducing blood cholesterol, not to mention the myriad other health benefits these changes can confer. If you have a high cholesterol level, work with your medical provider to find an overall lifestyle plan (and, if needed, a medical management plan) that works best for you.