How do eggs affect cholesterol levels?

From the Guidelines

Eggs have a minimal impact on blood cholesterol levels for most people, and moderate consumption, up to one egg per day, is considered safe and nutritious as part of a balanced diet. While eggs do contain cholesterol, research shows that dietary cholesterol has less influence on blood cholesterol than previously thought, as the liver adjusts its cholesterol production when we consume cholesterol-rich foods, maintaining balance 1. Saturated and trans fats have a much stronger effect on blood cholesterol than dietary cholesterol itself. Eggs also contain beneficial nutrients like high-quality protein, vitamins, minerals, and antioxidants like lutein and zeaxanthin that support eye health.

Some key points to consider:

• The majority of the population, referred to as 'normal responders', experience a small increase in plasma cholesterol levels when consuming dietary cholesterol, with a daily intake of 300-600 mg (corresponding to three servings of two eggs per week) having a minimal effect 1.
• However, individuals with certain genetic conditions, diabetes, or established heart disease may need to be more cautious with egg consumption, as they may be 'hyper responders' with an impaired inhibition of endogenous cholesterol synthesis during a cholesterol-rich diet 1.
• A western dietary pattern rich in foods with a high content of saturated fatty acids (SFAs) may also amplify the plasma cholesterol response to a cholesterol-rich diet, making it wise not to exceed a weekly consumption of three eggs in such cases 1.

It is essential to note that the effects of dietary cholesterol on plasma LDL levels appear to be greater at low versus high levels of cholesterol intake 1. Nevertheless, the most recent and highest quality study suggests that moderate egg consumption is not significantly associated with fatal or non-fatal coronary heart disease (CHD) in the general population 1. If you have concerns about cholesterol or heart disease, consult with your healthcare provider for personalized advice regarding egg consumption.

From the Research

Effects of Eggs on Cholesterol Levels

• Eggs are a rich source of dietary cholesterol, with approximately 141-234 mg per egg 2.
• The relationship between egg consumption and cholesterol levels is complex, with some studies suggesting that eggs may increase low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels 3, 4.
• A meta-analysis of randomized controlled trials found that egg consumption increased total cholesterol, LDL-C, and HDL-C levels compared to a control group, but had no effect on LDL-C:HDL-C and TC:HDL-C ratios, and triglyceride concentrations 4.
• Another study found that higher egg consumption (more than 1 egg/day) was associated with a significantly decreased risk of coronary artery disease, but not with an increased risk of overall cardiovascular disease events 5.

Cholesterol and Cardiovascular Disease

• Cardiovascular disease is the leading cause of death in the United States, and reducing dietary cholesterol has been a part of the American Heart Association (AHA) and American College of Cardiology (ACC) guidelines on lifestyle management 2.
• However, the 2015-2020 Dietary Guidelines for Americans removed the recommendation of limiting cholesterol intake to no more than 300 mg per day, and instead advise individuals to eat as little dietary cholesterol as possible while consuming a healthy eating pattern 2.
• A systematic review and meta-analysis found that lowering LDL cholesterol decreases the risk of ischemic heart disease events and stroke, with an estimated 61% reduction in IHD events for a 1.8 mmol/l reduction in LDL cholesterol 6.

Egg Consumption and Health

• The association between egg consumption and serum cholesterol concentrations in healthy people has been discussed for a long time, with some studies suggesting that eggs may have a modest influence on serum lipid concentrations 3, 4.
• A review of the literature found that the current recommendations on egg consumption and cholesterol intake may not be warranted, and that dietary patterns that emphasize fruits, vegetables, whole grains, low-fat dairy products, poultry, fish, and nuts may be a more effective approach to favorably alter blood lipid levels 2.
• Further studies are needed to fully elucidate the health effects of egg consumption, particularly in relation to cardiovascular disease risk and cholesterol levels 2, 5, 3, 4.