Yes, Egg Yolks Raise Cholesterol (and Mortality), But the Egg Industry is Hiding It
It’s a common back-and-forth debate: do egg yolks raise cholesterol? Research feels like a metronome, swinging from one opinion to its opposite every few years. Let’s take a deeper look as to why.
This topic can be broken down into two parts:
- Do egg yolks raise cholesterol?
- Do they impact our disease risk?
Do Eggs Raise Cholesterol?
From my few years as a dietitian and intern, I have seen my fair share of blood work from my in-patient hospital rotations. When I checked their labs before seeing them and noted high cholesterol levels, I would then ask them if they eat egg yolks. Very often I would hear a “yes.” I’ve coached clients as well who have high cholesterol and egg yolks are always part of the equation. Removing them always lowers cholesterol. Even when adding in olive oil and avocados, which are excellent for cholesterol control, if the egg yolks remain the results are hampered. From seeing such a consistent pattern, I find it hard to believe egg yolks are totally unrelated to cholesterol. But let’s take a look at the research.
I’ll get straight to the point: the confusion is the result of research abuse. The egg industry funds research that is set up to produce the result they want: that you can eat as many eggs as you want! Go egg wild!
Let’s take an example. This 2018 study suggests that egg consumption does not affect cholesterol at all. Of course, it’s an acute feeding. Of course it isn’t going to.
Of course, they still conveniently concluded that “These findings provide a mechanism to help explain why dietary cholesterol intake may not affect long-term plasma total cholesterol control.” Yeah, sure dude. You can torture the lab until it sings all you want. I almost never actually observe this in the real world, lab work and all.
Now if you scroll down and check out their funding, I doubt you’ll be surprised:
Let’s check out this American Egg Board about page:
The American Egg Board (AEB) was created by an Act of Congress in 1976 at the request of America’s egg farmers, who desired to pool resources for national category-level egg marketing.
Home to The Incredible Egg and Egg Nutrition Center, AEB is dedicated to increasing demand for all U.S. eggs and egg products. For more than 40 years, America’s egg farmers have supported this mission by funding the AEB. The AEB is 100 percent farmer-funded, and those funds directly support the research, education and promotion necessary to market eggs.
We are honored to serve America’s egg farmers.
This egg is indeed incredible. It’s a good thing that they’re honest, though!
History doesn’t repeat itself, but it does rhyme. This rhyme is a common theme on the topic. They’ll claim there is “no conflict of interest” and then thank the AEB for their funding. Deceptive nonsense. Whenever you read an egg study, do yourself a favor and check the funding sources.
Meanwhile this 2017 analysis of 28 studies found that egg consumption increased LDL by 5.55 mg/dL and total cholesterol by 5.60 mg/dL. Granted, how many of these studies were also funded by the egg industry? And how many eggs were they eating per week? Do industry-funded studies conclude that eggs are harmless whereas real research says otherwise?
Thankfully, someone already did the research on this question. This 2019 study investigated and found that “the percentage of industry-funded studies increased from 0% in the 1950s to 60% for 2010 to 2019.”
For example, in one study they asked college students to eat two eggs a day, five days a week, for 14 weeks. By the end of the study, their LDL cholesterol went up on average 15 mg/dL. Your LDL should be under 100 mg/dL, so that’s quite significant. Imagine if they did this for a full year, would the numbers rise even higher?
But the researchers of this study said it didn’t reach statistical significance, meaning there was more than a 5% chance that the increase could have occurred by chance. So they concluded that an “additional 400 mg/day of dietary cholesterol did not negatively impact blood lipids.” The skeptics in this meta-analysis said that it “would have been appropriate for the investigators to report that the cholesterol increases associated with eggs could have been due to chance. Instead, they wrote that the increases did not happen at all. Similar conclusions were reported in more than half of industry funded studies.” They went on saying that “it is important to differentiate between the absence of a statistically significant difference and the absence of a difference.”
This is quite disturbing given the CDC’s cholesterol facts in the United States:
- In 2015–2016, more than 12% of adults age 20 and older had total cholesterol higher than 240 mg/dL, and more than 18% had high-density lipoprotein (HDL, or “good”) cholesterol levels less than 40 mg/dL.
- Slightly more than half of the U.S. adults (55%, or 43 million) who could benefit from cholesterol medicine are currently taking it.
- 95 million U.S. adults age 20 or older have total cholesterol levels higher than 200 mg/dL. Nearly 29 million adult Americans have total cholesterol levels higher than 240 mg/dL.
- 7% of U.S. children and adolescents ages 6 to 19 have high total cholesterol.
- High cholesterol has no symptoms, so many people don’t know that their cholesterol is too high. A simple blood test can check cholesterol levels.
- Having high blood cholesterol raises the risk for heart disease, the leading cause of death, and for stroke, the fifth leading cause of death.
So it’s worrisome that this biased research has the power to influence our government policies. The 2015 Dietary Guidelines, for example, stated that “available evidence shows no appreciable relationship between consumption of dietary cholesterol and serum cholesterol.” As we’ve seen, this is nonsense. Their advice was updated to follow suite: “The Key Recommendation from the 2010 Dietary Guidelines to limit consumption of dietary cholesterol to 300 mg per day is not included in the 2015 edition.” But then they advised to eat “as little dietary cholesterol as possible,” because, they say, high cholesterol foods are often high in saturated fat. They pretty blatantly threw a bone to the egg industry, at the cost of America’s health. But money speaks louder than integrity.
Eggs and Dietary Cholesterol Raise Disease Risk
A new 2019 study in the JAMA took results from six studies including almost 30,000 people. In some of these they followed people for 10–30 years. The results show that egg yolk and general dietary cholesterol consumption increase risk of cardiovascular disease mortality and all-cause mortality. Even eating just half an egg per day resulted in a 6%-8% increased relative risk of having a heart attack, stroke, or early death compared to eating no eggs. When that number went up to one full egg per day the heart-related event risk went up to 12%. Two eggs per day on average yielded a 24% increased risk.
Now these numbers are relative risk, not absolute risk, which are what really matter in making a health decision. People who eat eggs could, for example, be eating generally less healthy diets, and vice versa. Absolute risk accounts for eggs being incorporated into an overall healthy diet. Thankfully, the researchers also included absolute risk.
The absolute risk for each half-egg consumed per day was 1.11% higher for cardiovascular disease and 1.93% higher for all-cause mortality. This is still significant. If you eat 3 eggs per day, even as part of an overall healthy diet, your absolute risk of all-cause mortality still goes up almost 6%. The numbers increase for every 300 mg of dietary cholesterol consumed, where CVD goes up 3.24% and all-cause mortality 4.43%.
It’s clear that eggs indeed raise cholesterol as well as disease risk. The misconceptions are not due to conflicting research, but meddling from the egg industry, conflicts of interest, and dishonest science. This in turn affects our government policies and negatively influences millions of American’s dietary intake through deception.