Today's Topic in Focus: [00:51]
In this episode Danny and Alan discuss the debate over the impact of dietary cholesterol on LDL-C levels and heart disease risk. Are eggs & cholesterol-rich foods a problem? Let's dive into the research to find out!
Referenced Material:
- Dietary Guidelines for Americans 2020 - 2025
- Hegsted et al., 1993 - Dietary fat and serum lipids: an evaluation of the experimental data
- Human Atherosclerosis and the Diet - Ancel Keys
- Keys et al., 1965 - Serum cholesterol response to changes in the diet: II. The effect of cholesterol in the diet
- Nakamura et al., 2013 - Serum leptin and total dietary energy intake: the INTERLIPID Study
- Schonfeld et al., 1982 - Effects of dietary cholesterol and fatty acids on plasma lipoproteins
- Fielding et al., 1995 - Effects of dietary cholesterol and fat saturation on plasma lipoproteins in an ethnically diverse population of healthy young men
- Ginsberg et al., 1995 - Increases in dietary cholesterol are associated with modest increases in both LDL and HDL cholesterol in healthy young women
- Episode #317: Understanding Diet & Heart Disease Risk
- Sigma Statement: The Impact of Diet on Blood Lipids
"I Have a Question!" [62:32]
Today's questions:
- Carlos Garcia: "Are the effects of plant sterols (on lowering LDL levels) in foods such as Danacol backed by evidence? How much of it is pure marketing?"
- Papers referenced in answer:
Nick Hiebert: "It is my understanding that the relationship between dietary cholesterol and blood lipids is hyperbolic in nature. When higher intakes are compared to zero intake, an increase in LDL cholesterol can be reliably observed, and the effect seems to plateau at 300mg/day. In epidemiology, low to high intakes almost never capture the range wherein the effect can actually be seen (0mg/day to 300mg/day). This has led to a prevailing paradigm that suggests that dietary cholesterol has little or no impact on the incidence of cardiovascular disease. But I'm not certain we can say this with confidence. I'd like to know your thoughts on this."
Quack Asylum [72:55]
Dismissal of the work of Ancel Keys, in favor of promoting high saturated fat intakes and high red meat intakes as not problematic.
Random Recommendations [75:28]
Alan's Recommendation: Twilight of Democracy - Anne Applebaum
Danny's Recommendation: Very Bad Wizards podcast (with a special mention of episode 181 discussing David Foster Wallace’s Good Old Neon)
Comments
I hope you also do a separate sigma statement on this topic. I would love to read that one. Thanks alan and danny for doing this podcast
Thank you. Some of the dietary cholesterol research is discussed in this Sigma Statement on blood lipids: https://sigmanutrition.com/diet-on-lipids/
Just started listening to the podcast! At the very beginning of this episode you mentioned that there have been previous episodes on dietary fats and how they influence blood lipids and cardiovascular disease in the show notes. Where can I find these show notes? I would love to listen to these previous episodes and read the Sigma Statements. Thanks!
Hi Trever,
You can find the podcast episode here: https://sigmanutrition.com/episode317/
And then there are three Sigma Statements…
Part 1: https://sigmanutrition.com/lipids/
Part 2: https://sigmanutrition.com/diet-on-lipids/
Part 3: https://sigmanutrition.com/diet-cvd/
Awesome podcast! I share episodes to my friends and clients regularly! Keep up the great work!
Thanks John!
Can you explain the Sydney heart study and the Minnesota heart study , replacing saturated fat with polyunsaturated fats saw mortality go up ?
Hi Steve,
“A number of studies in the 1960’s-1970’s purported to find a negative effect of omega-6 PUFA on heart disease. The first, the Sydney Diet-Heart Study, was a small RCT in which in the intervention group were provided with a margarine spread to replace SFA with PUFA; there was a significant increase in CVD mortality in the intervention group. However, the margarine in the intervention contained high levels of trans-fatty acids [TFA], which we know now have a pronounced negative effect on health, to the point where they have been largely removed from the food supply. At the time, however, foods labelled as ‘high in omega-6’ often contained high levels of TFA. Much of the hyperbole surrounding margarines, and surrounding a negative effect of replacing SFA with PUFA, were generated by studies like the Sydney DIet Heart Study.
The other study which warrants mentioning here is the Minnesota Coronary Experiment, in which in-patients at psychiatric hospitals in Minnesota were randomised to an intervention replacing SFA with PUFA. Decreasing blood cholesterol levels was associated with a significant increase in all-cause mortality in participants over 65yrs, irrespective of diet group. The age group here is critical, as arguments made that lowering blood lipids increases risk for adverse health outcomes are uniformly made from data in the >65yrs age group, however, it is often that low cholesterol reflects poor health – or in the case of cancer, onset disease – in these populations.”
From: https://sigmanutrition.com/omega6-inflammation/
We also have a 3-part series going into more detail: https://sigmanutrition.com/diet-cvd/
Or a longer podcast on CVD and diet, as well as one on inflammation. We discusss this in both episodes.
I have read a lot of information that eggs are unhealthy due to other factors than just cholesterol. What are your thoughts on the consumption of eggs in your diet? Thanks.
Hey Melissa,
As always, I think it’s important to put any food into the context of your overall dietary intake and the amount of that food being consumed. With an overall healthy dietary pattern, from a health perspective, there would be no need to avoid consuming eggs. They contain various micronutrients, and can be a useful source of protein. As long as someone isn’t consuming so many eggs that it replaces the intake of beneficial food groups, then I find it hard to make a case that they are unhealthy.