Up to an Egg a Day Is Fine, Scientists Say

For decades, people have been confused about whether it is safe to eat eggs. Doctors warned that yolks contain a lot of cholesterol and worried that might translate into atherosclerosis for omelet lovers. Several years ago, a global study showed that people can safely eat as much as an egg a day. They don’t increase their likelihood of a heart attack with such a diet. Then US scientists published independent research that came to the same conclusion. Read on for that information. One reader has a different question about the safety of egg consumption: Do they need to be washed first?

Should You Wash Your Egg Before You Cook It?

Q. I have a question about washing eggs. Generally, just before I crack them open, I give them a quick rinse. However, I have read this practice could potentially drive any contaminants inside.

I have seen many people open a carton and handle the eggs prior to purchase to make sure none are broken. That’s why I worry about contamination.

Additionally, there is the question of bird flu. Since it is a respiratory virus, there is a possibility the handlers may carry it.

If one were to wash them, would that be advisable for farmer’s eggs that presumably have a protective coating on their shells? What about eggs that have been washed and sanitized by their packing companies?

A. Eggs that are commercially packaged should not be washed before you cook them. They have already been properly prepared, though we do advise washing your hands carefully after cracking raw eggs and disposing of the empty shells.

Eggshells are porous, so washing them could carry bacteria through the shell. If you are uncertain about those you buy at the farmers’ market, clean them with a dry towel before you crack them. Once again, wash your hands with soap and water afterwards.

The USDA recommends cooking eggs thoroughly (to a temperature of 160 F) before eating them. That’s always been a best practice for avoiding salmonella, but it is even more urgent with bird flu circulating.

Eating as Much as an Egg a Day Is Safe for the Heart:

Now on to the question of whether you can eat eggs without risking heart disease. One study concluding an egg a day is safe included data on more than 200,000 American health care professionals (The BMJ, March 4, 2020). The investigators collected dietary information on these nurses and male health care professionals every few years and followed them up for decades. With over 5.5 million person-years of observation, they feel very confident in their conclusions. The researchers found no link between egg consumption and cardiovascular disease.

In fact, the authors concluded:

“Results from the three cohorts and from the updated meta-analysis show that moderate egg consumption (up to one egg per day) is not associated with cardiovascular disease risk overall, and is associated with potentially lower cardiovascular disease risk in Asian populations.”

An accompanying editorial warns that such an observational study can’t establish cause and effect.

It observes instead that the overall diet is more important than whether you eat an egg a day:

“If frequent egg consumption is occurring in the context of an overall dietary pattern known to be cardioprotective, or eggs are being consumed for essential nutritional needs, then it is probably nothing to worry about. If frequent egg consumption is occurring in the context of a typical Western dietary pattern (high levels of refined grains, added sugars, red and processed meats, and ultraprocessed foods), the best evidence for cardioprotection supports shifting one’s overall dietary pattern to a Dietary Approaches to Stop Hypertension (DASH) or Mediterranean diet.”

Nonetheless, this is not the first study suggesting that it may be safe to eat an egg a day. Years ago, we received this question from an anxious wife:

Is It Really Safe to Eat Eggs Sometimes?

Q. My husband loves eggs and used to eat them several times a week. When he was told 25 years ago he had a cholesterol problem, he gave up eggs, butter and saturated fat.

Even with a good diet, his cholesterol stayed high. The doctor decided five years ago that my husband needed a cholesterol-lowering drug. He now takes Pravachol, which keeps his cholesterol around 180.

We just read that eggs are not a problem any more. This is hard to believe, but would it be all right for him to eat them once in a while?

Eating Up to an Egg a Day Is Fine:

A. As heretical as it may sound, eating up to an egg a day does not appear to increase most people’s risk of heart attack or stroke. In fact, the most recent meta-analysis of 16 studies including more than 1.2 million volunteers found that people who eat eggs lower their risk (Angiology, Jan. 31, 2020).

These investigators wrote:

“In conclusion, egg consumption is independently associated with low incidence/mortality of CAD [coronary artery disease], which may be derived from the comparisons of the fifth versus first quintile egg consumption.”

Learn More:

If you would like to learn more about how to follow a Mediterranean diet or a DASH diet, you might want to read our book, The People’s Pharmacy Quick & Handy Home Remedies. In it, we included details on both these dietary patterns along with many of our favorite healthy foods.