Cholesterol Confusion

I believe that sometimes there can be too much of a good thing. People have been given so much nutrition information in the past 20 years that they no longer know what is good or bad. Are carbohydrates important for energy or will they make you obese and diabetic? Are fats bad for your heart or good for your brain? Should I eat fish because it's good for me, or will the mercury kill me? Part of the problem is that these questions are not simple yes or no issues, but the other part is that everyone now has a lot of information about food and diet, much of it conflicting, and for the average consumer the unending and rather confusing stream of messages can make every day diet decisions a serious challenge. I recently read a great book about decision making, that discusses the role of information overload in hampering our ability to chose. The book is called How We Decide, by Jonah Lehrer. It's a great read and I hope some of you choose to pick it up.

So I have received several questions along the lines of "what is really true about this food?" I can't answer them all in one post, so I am going to take this one:

Egg yolks- I am very confused. You hear that they raise cholesterol, but I also know much of the nutrition in the egg is in the yolk.

A lot of people are confused about eggs and cholesterol. I am going to try to keep this answer as simple as possible. For most healthy people, the amount of cholesterol they get in diet doesn't really have much to do with the cholesterol in your blood. Most of the cholesterol your doctor finds and measures on your blood test is manufactured by your liver from fats that you eat. A diet high in saturated fat or trans fats will do much more to elevate cholesterol in your blood than the amount of cholesterol you consume. Genetics, and conditions like insulin resistance also contribute. So, generally speaking if you are pretty healthy and have never had high cholesterol on a blood test, you should not get terribly concerned about consuming high cholesterol foods like egg yolks.

The story is a bit different if you have high cholesterol. If you have had high cholesterol on a blood test, studies have shown some benefit in keeping your dietary intake of cholesterol below 300 mg per day. Since a large egg with the yolk has about 200 mg of cholesterol, that still means that people with high cholesterol can enjoy eggs - but they should probably limit themselves to one per day, and try not to consume other high cholesterol foods like shrimp on the same day. If you have high cholesterol and you want to consume a big fluffy omelette, use one whole egg and one or two egg whites. This way you get all the great nutrition in the yolk. Just so you know I am not making this up, the data from the largest US population study of heart disease ever done (the Framingham Heart Study) has shown no correlation between egg eating, serum cholesterol and heart disease (click here to read).

As the questioner notes, while the white of the egg has the protein, the real nutrition is in the yolk. Egg yolk contains all the fat-soluble vitamins (A, D, E and K), lecithin, B1, B2, B5, folic acid, calcium, iron and zinc - I mean WOW!

Now I know once I post this there will be other questions, so here are a few of the answers:

1. Be careful of egg substitutes. If you are vegan and you have baking needs, there are some good products from companies like Ener-G, but if you are considering commercial liquid egg replacers, be careful. They are mostly egg white anyway, so just separating your eggs and using the whites is less expensive and healthier.
2. You can buy eggs now that are fortified with omega-3 fatty acids. I think this is great.
3. Buy organic. I am in general a fan of organic foods. But I think some foods are more important that others and eggs are one. Commercial non-organic eggs are produced with a lot of antibiotics and hormones. If you are going to enjoy the goodness of eggs, no need to spoil it with hormone and antibiotic residue. And truly - try for yourself if you need to - organic eggs taste a lot better than commercial eggs.

So I hope that clears up someone's confusion today! I will eventually try to tackle similar questions about sweeteners, fats, and more, so stay tuned.

In Health,

Dr. Jacques