One Major Side Effect of Eating Eggs, Says Science
This probably isn't news to you, but eggs just may be the most affordable, versatile, convenient form of protein. Not only are they loaded with antioxidants, essential minerals, and amino acids, they also boast fat-fighting choline, bone-strengthening vitamin D, and brain-boosting vitamin B12. Studies have shown that eggs can increase your energy, support your immune system, reduce inflammation, protect your eyes, and enhance the appearance of your skin and hair—and that's only a few of their many superpowers. Honestly, is there anything eggs can't do? But whether you enjoy them fried, scrambled, or hard-boiled, there's one major side effect of eating eggs that you should know about—and it has to do with your cholesterol profile. (Related: The 7 Healthiest Foods to Eat Right Now)
Research findings on eggs' impact on cholesterol is pretty confusing. Some studies have suggested that they may increase your risk of heart disease by raising your cholesterol levels. Other studies have indicated that eating half a dozen eggs a week has no negative effect on cholesterol whatsoever. So, which is it?
Here's the short answer: Eating eggs regularly can affect your cholesterol profile—but not necessarily in a negative way.
A 2019 JAMA study revealed that eating an average of just three to four eggs per week was associated with a higher risk of cardiovascular disease (CVD). For each additional half an egg consumed daily, the risk of CVD went up by 6%. But here's the caveat: As Harvard Health points out, not only was the effect observed quite modest, but this study was observational in nature, and therefore can not prove that eating more eggs actually caused the elevated risk of CVD. The Harvard Chan School of Public Health noted that multiple previous studies have demonstrated that low to moderate egg intake is not linked to a higher risk of CVD in generally healthy people.
As you may or may not know, there are both good kinds of cholesterol (HDL) and bad kinds (LDL). One large egg has 212 milligrams of total cholesterol. However, according to Harvard Health, eggs have been shown to raise the good kind. LDL cholesterol is considered bad because these particles have a tendency to block artery walls with their fat molecules (whereas HDL can actually get rid of the fat that clogs arteries). However, as Harvard Health reports, bigger LDL particles are less likely to raise your risk of heart disease than smaller ones. And remarkably, eggs can increase the size of LDL particles, thus shrinking your risk of cardiovascular problems.
Research has also shown that LDL cholesterol is far more inflammatory and generally harmful when it's oxidized, thus building dangerous plaque in your arteries. But as it turns out, not all eggs are created equal. A 2011 study published in the Journal of Agricultural and Food Chemistry found that when hens are fed with a diet that's low in omega-6 fatty acids—in other words, lower in soy, maize, sunflower, and safflower and higher in wheat, barley, and milo—they produce eggs that may cause less oxidative damage. Likewise, a 2008 study by the same lead researcher revealed that eggs high in omega-3 fatty acids caused 30% less cholesterol oxidation than eating eggs higher in omega-6s.
The consensus seems to be this: Choosing eggs that are high in omega-3s could help to minimize health risks from ingesting more cholesterol. And unless you already have high cholesterol or diabetes, have had a heart attack, or are otherwise at high risk of CVD, there's no reason why you shouldn't enjoy eggs on the reg. According to the Mayo Clinic, most healthy people can eat up to seven eggs a week without increasing their risk of heart disease. In fact, a 2018 study found that eating up to one egg per day can actually lead to a lower risk of heart disease. If you're really concerned about your cholesterol levels, you can also nix the yolks—egg whites still contain a notable amount of protein without any of the cholesterol.