Although eggs have gained acceptance as a food to include in a healthy diet, public health experts have been reluctant to recommend regular egg consumption due to the fear that the cholesterol they contain will cause heart disease.
With new evidence from a study from China showing that egg consumption is linked to lower risk of heart disease and stroke, experts and the general public can rest easier about regularly eating eggs is protective for health. This study was a massive investigation of nearly half a million people that was published in the well respected journal Heart, which is part of the British Medical Journal. Researchers followed 512,891 subjects aged 30 to 79 and interviewed them about their regular egg consumption, assessing cardiovascular health and death rates over a nine-year period.
At the start of the study period, 12 percent of participants ate eggs daily and 9.1 percent reported never or very rare consumption of eggs. Analysis of the results showed that compared with people not consuming eggs, daily egg consumption was associated with a lower risk of heart disease overall. Daily egg consumers had a 26 percent lower risk of stroke, a 28 percent lower risk of death from stroke, and an 18 percent lower risk of death from cardiovascular disease. Additionally, there was a 12 percent reduction in the risk of ischemic heart disease in people consuming eggs daily compared to those who never or rarely ate eggs.
The study authors note that although eggs are a major source of dietary cholesterol, it has no established causal effect on cardiovascular disease risk. Additionally, the authors theorize that eggs contain other components that have a favorable effect on cardiovascular health. The phospholipids in eggs increase the good HDL cholesterol and improve HDL function, slowing down the progression of atherosclerosis (hardening of the arteries). Eggs also provide a high-quality protein that increases satiety and moderates blood sugar and insulin release. Eggs are linked with lower food intake at subsequent meals, making them useful for weight management in normal and overweight individuals.
Finally, eggs provide two powerful antioxidants, lutein and zeaxanthin, which protect against oxidation, inflammation, and atherosclerosis. Interestingly, lutein and zeaxanthin, which are carotenoids, have higher bioavailability from eggs than carotenoids derived from vegetables or fruit, likely due to the fact that the fat provided in the egg improves absorption.
How Many Eggs?
The highest egg intake that this study looked at was one egg a day. Possible egg questionnaire answers for consumption were daily, 4 to 6 days per week, 1 to 3 days per week, 1 to 3 days per month, and never or rarely, so this study doesn’t give us any information as to the pros and cons of a higher egg consumption, which is important because if you are eating eggs as a meal, you will probably want to eat more than one at a time.
Fortunately, we have a couple of other studies showing benefits of three eggs a day for improving cholesterol levels (raising the good HDL and improving the HDL to LDL ratio) and lowering inflammation. It’s possible more could be beneficial, however, we know from stories of the overconsumption of other foods that more is not always better. Additionally, foods that are eaten chronically have a tendency to cause intolerances, which harms the gut, so it’s probably a good idea not to go overboard with eggs.
A few pieces of advice when incorporating eggs into your diet:
Eat eggs with whole foods: Poach them with sautéed greens and baked sweet potato bites. Eat them hardboiled with a salad. Make egg salad and roll it up in a big lettuce leaf. Avoid eating eggs with refined carbs (toast and jelly) or processed meat (sausage and bacon), which is not a particularly healthy combination.
When possible, opt for organic, free-range chickens or local eggs from small batch farmers because these eggs tend to have a healthier fatty acid profile and the hens have a more humane life. Salmonella risk is also lower in non-industrially produced eggs.
Cook your eggs in a variety of different ways. Eating eggs prepared in the same way every day makes it more likely you will develop a food intolerance. Diverse cooking methods denature the proteins differently, which can help reduce risk of a poor digestive response to frequent egg intake. If you do have an egg intolerance, eating well cooked eggs in small amounts as part of a meal with other foods has been shown to reduce the immune response and repair tolerance.
Ballestros, M., et al. One egg per day improves inflammation when compared to an oatmeal breakfast without increasing other cardiometabolic risk factors in diabetic patients. Nutrients. 2015. 7, 3449-3456.
Chenxi Qin, et al. Associations of egg consumption with cardiovascular disease in a cohort study of 0.5 million Chinese adults. 2018. Heart.
DiMarco, D., et al. Intake of up to 3 Eggs/Day Increases HDL Cholesterol and Plasma Choline While Plasma Trimethylamine-N-oxide is Unchanged in a Healthy Population. Lipids. 2017. Published Ahead of Print.
Ratliff, J., et al. Eggs modulate the inflammatory response to carbohydrate restricted diets in overweight men. Nutrition and Metabolism. 2008. 5(6).