Two eggs at breakfast, and a little voice reminding you about cholesterol. For decades, eggs were filed among the foods to watch because of their yolk. Many women learned to eat only the whites, or to count their eggs by the week. The research has moved a long way since then, and it does not say quite what we were told.
One point before we start. I am not giving any advice here on lowering cholesterol. If yours is high, that is something to look at and decide with your doctor.
Cholesterol on your plate is not cholesterol in your blood
Your body needs cholesterol, for its cell membranes and to make its hormones. It produces most of it itself, mainly in the liver. What you eat adds to that production, and the body adjusts.
The response varies enormously from one person to the next. According to a review from the University of Connecticut, about two people in three barely react to the cholesterol in eggs. In the others, LDL goes up, the one called bad cholesterol, but HDL, the good one, goes up as well, and the ratio between the two usually stays the same (Blesso and Fernandez, 2018).
What the trials show
A meta-analysis published in 2015 pooled the trials that added cholesterol to people's diets, often in the form of eggs. On average, total cholesterol rose by 0.29 mmol/L, LDL by 0.17 mmol/L and HDL by 0.08 mmol/L. The LDL to HDL ratio rose slightly. In the follow-up studies, the authors found no statistically significant link between cholesterol eaten and coronary heart disease, and they judged the data too inconsistent to draw a conclusion either way (Berger et al., 2015).
In Sydney, 140 people with excess weight and prediabetes or type 2 diabetes were randomly assigned for three months. One group ate two eggs a day, six days a week. The other ate fewer than two eggs a week. At the end, there was no difference between the groups in total cholesterol, LDL, HDL, triglycerides or blood sugar. Both groups, guided by the team on what they ate, had also increased their unsaturated fats. The egg group, however, felt less hungry after breakfast (Fuller et al., 2015).
And the heart
In 2013, a meta-analysis of large follow-up studies found no link between eating eggs, up to one a day, and the risk of coronary heart disease or stroke. In the subgroup of people with diabetes, though, those who ate the most had more coronary heart disease (Rong et al., 2013).
In 2020, Harvard researchers followed more than 215,000 nurses and health professionals for up to 32 years. Eating at least one egg a day was not linked to more cardiovascular disease. Their updated meta-analysis, covering more than 1.7 million people, reached the same conclusion (Drouin-Chartier et al., 2020).
Not every study points this way. In 2019, an analysis of six American cohorts, nearly 30,000 people, linked each extra half egg a day to a slightly higher cardiovascular risk, by 6% (Zhong et al., 2019). These are observational studies. They spot links, they do not prove that eggs are the cause, and people who eat a lot of eggs often have other habits that count too.
The American Heart Association reviewed the question in 2020. Observational studies generally show no significant link between dietary cholesterol and cardiovascular disease. Trials, for their part, most often link intakes above the average to slightly higher LDL. Recent guidelines have also dropped the numerical daily limit on cholesterol (Carson et al., 2020).
Judge the whole food
We learned to judge a food by a single component, cholesterol for eggs, saturated fat for meat. Yet a doughnut contains more saturated fat than minced beef at 15% fat. I prefer to look at the whole food. An egg, a piece of meat or a full-fat yoghurt are quality foods. Natural saturated fats have not shown a solid link with cardiovascular disease in the large recent analyses. Replacing them with refined carbohydrates and vegetable oils rich in omega-6 is no improvement.
If your cholesterol shifted around fifty, eggs are not necessarily the reason. About eight women in ten see their cholesterol change during the menopause transition, without changing anything in their lifestyle. LDL goes up, HDL goes down.
Why the number rises as you lose weight
One last point surprises a lot of people. In 1991, an American team followed six women with obesity through a major weight loss, about 30 kg in five to seven months. Their total cholesterol first fell from 5.49 to 3.62 mmol/L within one or two months. Then it climbed back to 5.95 mmol/L while they kept losing weight. Once their weight was stable, it came down to 4.92 mmol/L. The authors think cholesterol stored in fat tissue goes back into the blood as that tissue melts away (Phinney et al., 1991).
It is also what I see in coaching. During weight loss, total cholesterol often rises for a while, as it does for everyone, then settles once the loss is over. In the people I coach who follow the Totem protocol, HDL is high and LDL is low, or going down.
If you have a blood test in the middle of losing weight, tell your doctor, they will read the numbers differently. A full lipid panel, before and then a few months after you change how you eat, shows what is really going on, especially if you are eating more natural fats than before. Do it with your doctor, particularly if you have a cardiovascular or metabolic history.
Egg yolk never deserved its reputation. Your test results deserve to be read with someone who knows your story.
This article is for information only and does not replace medical advice.