Bad News For Egg Lovers

A new study finds a link between a compound in egg yolks and heart disease.

Egg yolk

Egg yolk photo via Shutterstock

We already ruined tonight’s dinner by reporting on a link between red meat and heart disease, and now your breakfast is under attack, too. The same researchers behind the red meat study, a team of doctors at the Cleveland Clinic, are now saying egg yolks can increase your risk of heart disease as well.

Egg yolks contain a compound called lecithin that, when broken down during digestion, is made into a chemical called choline. When choline is metabolized by intestinal bacteria, it is converted into a chemical called TMAO, the same one that is produced when red meat is metabolized. The production of TMAO is the problem—when it’s found in the blood stream, it increases the odds of heart disease, heart attack, and stroke. Though more research needs to be done to conclusively prove that TMAO is what’s actually increasing heart disease risk, a New York Times article says the study’s author, Dr. Stanley Hazen, recommends people cut down on lecithin in their diets by eating fewer foods high in cholesterol and fat.

When taken together, these two studies raise the compelling question of just how much of an impact gut bacteria has on heart disease, and whether targeting TMAO with pharmaceuticals or probiotics is the best way to proceed when trying to prevent heart disease.

The study only shows one side of the story, though, when it comes to egg yolks. Egg yolks have been under attack for years for their high cholesterol and fat content (hence the rise of the egg white omelette), but they do have health benefits, too. Eggs, yolks included, are relatively low in calories and contain more than a dozen vitamins and minerals, protein, unsaturated fats, and antioxidants. Further, research has shown that the amount of cholesterol you consume from eating approximately an egg a day poses no serious threat to healthy individuals. All things considered, we’re inclined to think the good old “everything in moderation” mantra still applies.