This was in my email today “WSJ News Alert: Study Links Eggs to Higher Cholesterol and Risk of Heart Disease”1. I find it amazing we have to keep dealing with these types of stories.
This is the study in question: “Associations of Dietary Cholesterol or Egg Consumption With Incident Cardiovascular Disease and Mortality”2
I disagree. This post is not meant to be a complete analysis, just an initial review for context as the terrible headlines are circulating.
This is one of those massive surveys where they track 30,000 people and work backward to various nutrient makeups of the diet. Even the study admits this as a limitation. How accurately would you fill out a form periodically on what you ate?
I typically start with funding, because it helps determine if there is a potential desired outcome.
“This study was supported by a postdoctoral fellowship to Dr Zhong from the American Heart Association Strategically Focused Research Networks (14SFRN20480260; principal investigator, Greenland)”
The good ‘
“These findings are consistent with the evidence that a reduction of dietary cholesterol intake, in addition to isocaloric replacement of saturated fat by unsaturated fat, was significantly associated with reduced total cholesterol (primarily LDL cholesterol) concentration.”
Replacing saturated fat with unsaturated fat in junk oils such as canola is the message – and if followed, health will decline.
Then you have the conflicts, you will see many of these companies in another AHA discussion on salt restriction advocacy.
“Conflict of Interest Disclosures:
First Read Data Anomalies
The assertion was that dietary cholesterol from eggs leads to heart attack and all-cause mortality. I am not a statistician, even though I took a class in college, but having a representative data set would be a great place to start.
The study had blacks composing 31% of the data set, despite the census showing 13%. The problem here is that blacks have a higher death rate 3and a higher risk for cardiovascular disease.
“But even after adjustment for factors related to socioeconomic differences, disparities in rates of heart disease and its risk factors persist, Dr.
Women are 50.8% according to the census yet were 55.1% of this study. The authors declared that the association between dietary cholesterol and all-cause mortality was stronger in women. Hmm, more of the stronger association of your theory included.
These two demographic details alone skew the applicability to a broader population.
From the article directly: “This study has several limitations. First, appropriate interpretation of the study findings requires consideration of measurement error for self-reported diet data. Further, this study relied on
Reading through this paper was like an uncomfortable trip down memory lane to my stats class. I learned a few tricks in there, but basically, if you try hard enough you can massage data any way you want.
“Facts are stubborn things, but statistics are pliable.”
― Mark Twain
“There are three types of lies — lies, damn lies, and statistics.”
― Benjamin Disraeli
There were multiple models, Energy-adjusted Pearson correlations, 6 cohorts, regressions, absolute risk, hazard ratios, and more. I think there were potentially more statistical terms in this paper than my entire college textbook.
“If your experiment needs a statistician, you need a better experiment.”
― Ernest Rutherford
This is just another in the long line of advocacy studies. Pasture raised, organically fed egg yokes are among the most nutritious foods on the planet (and not mentioned here versus caged and feed laced with arsenic). Eat them often. The reason they are picked on here is that the cholesterol content is high. The high cholesterol myth leads people away from real foods to Big Processed Food Alternatives. They have debunked the whole dietary cholesterol theory anyhow5. There is a regulatory mechanism in place to keep cholesterol levels adequate. If you don’t consume cholesterol, your body makes it, if you do it makes less.
Eggs are nutritious, enjoy them and other whole single ingredient foods (ie, this package contains steak) and your health will improve. The longer the ingredient list, as found in the foods that get recommended in cholesterol avoidance scams, the more problematic health consequences.