Eggs have long been placed on the “Do Not Eat” list by cardiologists and primary care doctors alike who are counseling their patients on heart healthy diets. In fact, even in the face of new research supporting the health benefits of eggs, many still think that their dietary cholesterol intake has a direct impact on heart disease risk. Let’s see what the research says!
First, of all, what is cholesterol?
Cholesterol is a waxy like substance found in every cell in your body that is needed to make hormones as well as Vitamin D. The liver is responsible for making much of your body’s cholesterol (around 70%). When we eat less dietary cholesterol, our liver compensates by making more. When we eat more, our liver makes less. We also know that saturated fat has more of an impact on raising total cholesterol levels than actual dietary cholesterol. Research also seems to be pointing less and less to saturated fats increasing your risk for heart disease. The real fat to watch out for seems to be trans fats and those high in Omega 6s (processed and chemically refined vegetable and seed oils) that promote inflammation and cellular damage.
What’s the Research Say About Eggs?
Previous recommendations by the American Heart Association stated that intake of cholesterol should not exceed 300 mg daily. One egg contains over 200 mg of cholesterol, meaning that they are generally considered to be a high cholesterol food. However, many recent studies have shown that eating eggs may actually lower the risk of heart disease, and one such (opens in a new tab) found no association with dietary cholesterol or saturated fat intake and heart disease risk. In fact, the USDA 2015-2020 dietary guidelines removed their previous recommendation to limit dietary cholesterol to 300 mg daily and noted it is no longer a nutrient of concern in relation to heart disease.
(opens in a new tab) study found that whole egg consumption as part of a moderately low carbohydrate diet (25-30% of total intake) improved lipid profiles (decreased triglycerides, increased HDL and increased large, harmless LDL particles) more so than an egg white consumption. And if you want more evidence that eggs have been unjustly condemned, this (opens in a new tab) found that eating three eggs daily for 12 weeks did not increase risk of CVD in those with Metabolic Syndrome, and consuming egg whites in their place did not decrease risk of CVD either.
Nutrition in Eggs
The egg white is where most of the protein in the egg is found, but the egg yolk contains the nutrient choline as well as essential vitamins and minerals like vitamin B12, biotin, selenium, vitamin D, vitamin A, calcium, zinc and phosphorus. The egg yolk also contains heart healthy Omega 3s. One egg contains 6 grams of protein and 5 grams of fat (including close to 2 grams of saturated fat).
Just like humans, animals store excess toxins in their fat cells. For this reason, it’s best to choose eggs that are organic and pastured. The animals are treated more humanely and eat a much healthier diet free from GMO and pesticide laden grains. Unfortunately, labels like “cage free” and “free range” sound great but are not regulated and can really mean a lot of things, so look for certifications like “USDA Organic” or “Certified Humane”. Chickens that are free to roam, are not fed toxic feed laced with antibiotics and are fed Omega 3 enriched flaxseeds are the gold standard for eggs. At the very least we recommend consuming organic eggs, and if you can get them from a local farm, that’s even better!
What are the benefits of eating eggs?
Eggs contain nutrients that are especially important to both brain and heart health. They contain betaine which has been shown to lower risk of heart disease by reducing levels of homocysteine, a byproduct of amino acid metabolism that can increase risk for heart disease by damaging the walls of our blood vessels. Increased homocysteine has also been linked to increased risk of cancer and Alzheimer’s Disease.
Eggs are also a great source of choline. Choline is a key nutrient in cellular membrane integrity. Two important molecules in the brain that make up much of the brain’s total mass (phosphatidylcholine and sphingomyelin) also include choline making it essential for brain function and cognition. Cholesterol is also important for brain health, joint health and for making sex hormones and Vitamin D.
A note about recent headlines…
While many rigorous studies showed that eggs are benign when it comes to heart disease risk, a recent study published in 2019 in JAMA found that eating around 2 eggs a day increased risk of CVD and death by 17% and 18%, respectively. So, what are we to think? Well, consider these points: the study followed nearly 30,000 people over the course of many years (on average 17 years) and the participants were asked about their dietary intake just once at the beginning of the study. We also don’t know if these people had other unhealthy habits that may have contributed to the increase in heart disease. The other flaw is that epidemiological nutrition studies like this one cannot draw cause and effect conclusions, but rather they find a correlation. Correlation does not equal causation, meaning that this study cannot say that eggs cause heart disease. The inflammatory headlines in the media that claimed that eating eggs causes heart disease are misleading. I always recommend reading the study itself or asking a trained professional to interpret the results rather than relying on media headlines. Nutritional research will always be challenging because these studies are often observational (think correlation again, not causation) and rely on participants being honest and accurate about their dietary intake. Check out Dr. Mark Hyman’s explanation (opens in a new tab) if you want to know more about why this study wasn’t what it was “cracked” up to be (pardon the pun).
We promote egg intake as part of a healthy diet for most people. However, everyone has unique needs and dietary preferences that we always take into account when giving nutritional advice to our clients!