You've tried so hard to be healthy. You watch your calories, exercise regularly and always toss out the yolks when you make your veggie omelet. Well, it may be time to reconsider! (At least when it comes to your eggs.) Whole eggs don't raise your risk of heart disease -- in fact, according to nutrition coach Liz Wolfe, NTP, author of Eat The Yolks, it may be worse for your health to not eat them.
The Scrambled Facts
Egg yolks, along with other sources of saturated fat and cholesterol, came under fire in the wake of research by Nikolai Anichkov at the turn of the 20th century. Anichkov fed rabbits pure cholesterol and noted that their arteries clogged up with plaque, leading to a hypothesis that cholesterol promotes heart disease. But since then, there have been questions raised about how closely the two are related. Wolfe counters: “Rabbits have nothing in common with human bodies ... and cholesterol isn't part of their diet anyway.”
Nevertheless, the findings gave rise to a witch hunt that demonized foods high in fat and cholesterol. Researcher Ancel Keys made headlines in the 1950s with his Seven Countries' Study, which almost single-handedly set the line of thinking on saturated fat that prevails today. Keys claimed that after looking at the average diets of populations in seven different countries, he was able to determine that those who ate the most animal fat had the highest rates of heart disease. But his analysis was flawed. Although Keys' data did show a connection between fat and heart disease, he couldn't demonstrate that the relationship was causal. Furthermore, while mortality rates for heart disease were higher in the countries that consumed the most animal fat, deaths from nearly ever other cause were lower -- and overall life expectancy was higher.
The Sunny Side Of Things
Thankfully, more concrete findings have come to light in the years since. In 2010, The American Journal of Clinical Nutrition published a meta-analysis -- the collected findings of 21 different studies -- which stated that "saturated fat was not associated with an increased risk of coronary heart disease, stroke or coronary vascular disease."
Earlier this year, Time magazine reversed the argument it made in a 1984 cover story claiming eggs and other high-fat foods were dangerous, and even encouraged readers to eat butter over margarine.
So what is the real cause of heart disease? Wolfe suggests it lies in the inflammation caused by "chronic stress levels, and the overconsumption of vegetable oils and processed carbohydrates." In other words: "Limit foods that come in boxes and bags."
The Hard-Boiled Truth
Meanwhile, if you've been avoiding egg yolks, you've been missing out on a world of good nutrition. According to Wolfe, "They're a great source of vitamin A, which is good for skin, B vitamins for energy and choline, which supports brain health, muscles and is necessary for a healthy pregnancy." The saturated fat in yolks is also necessary for hormone production and the body's absorption of vitamins and minerals.
As long as you control your overall calories, whole egg consumption won't cause weight gain, despite its fat content. However, if you're trying to hit certain macronutrient numbers for a diet, or just want to restrict calories, having a few white-only eggs can be appropriate. When in doubt, check in with a nutritionist to see how well your current food choices stack up against your health and fitness goals.
Correction: A previous version of this story stated that egg whites block biotin absorption. This is only true of raw egg whites.