Cholesterol, epistemology and diet

Hi Docs,

My cholesterol levels has been elevated since I started lifting about 2 years ago. My family doctor is a bit concerned. My guess is because I’ve been more liberal in meat and milk (2% fat) consumption. Except in the initial few months in LP, my body weight has been very stable. So, my calories intake has been “at maintenance”.

Sex: M
Age: 47
Height: 172cm (5’8")
Weight: 71kg (156lbs)
Waist: 34" (Asian)
Body fat: ~20% (readings from bathroom scale & caliper; and visual)

Training history: LP for 3 months, then fooling around with TM and (non-BBM) HLM. TM failed badly. HLM gave me progress but slow progress. Recently on Bridge 1. Will start Bridge 3 soon.

Fasted Lipid Studies:

Total Chol: 6.6 mmol/L (255 mg/dL) → Recommended level 5.5 mmol/L (213 mg/dL)
HDL: 2.1 mmol/L (81 mg/dL)
LDL: 3.9 mmol/L (151 mg/dL) → Recommended level 2.5 mmol/L (97 mg/dL)
non-HDL: 4.5 mmol/L (174 mg/dL)
Triglyceride: 1.2 mmol/L (106 mg/dL)

LDL/HDL ratio: 1.9
Chol/HDL ratio: 3.1

All my other readings (e.g. blood pressure, glucose level, etc) are well within the normal range.

Questions:

  1. The general guideline from my family doctor is to reduce saturated fat (and, by extension, fast food) consumption. Will this be your recommendation too?

  2. However, some recent researches [1, 2, 3], particularly by Kummerow (of trans fat fame and credibility [4]), indicate the culprit of heart disease is oxysterols (oxidised cholesterol?), not cholesterol, and it is unsaturated fats more susceptible to oxidisation, not satuarted fat. Kummerow recommends consuming saturated fats and avoiding unsaturated fats.

When you face minority views like this which disagree with or even contradict the general consensus and official guideline, how do you approach them? Do you side with the consensus until the consensus changes? However, from the history of trans fat, we can see the official guideline can fall far behind the actual science. Will there be objective factors which make you switch your view before the majority does?

  1. I’ve started altering my diet to lower my fat intake. One thing I’ve done: switching out peanut butter toasts and switching in oatmeal for breakfast. To my surprise, this gives my constipation. I’m already consuming plenty of water. The symptom has persisted for a week. I’m pretty sure oatmeal is the culprit. When I stopped eating it, the constipation went away in 1-2 days. On the net, there are sporadic “reports” that oatmeal caused constipation to some people. What gives? Is it just because of a change of diet? Will my digestive system adapt and will the constipation go away?

[1] Interaction between sphingomyelin and oxysterols contributes to atherosclerosis and sudden death - PMC
[2] The relationship of oxidized lipids to coronary artery stenosis - PubMed
[3] https://annals.org/aim/article-abstract/1846638/association-dietary-circulating-supplement-fatty-acids-coronary-risk-systematic-review
[4] https://www.washingtonpost.com/news/to-your-health/wp/2015/06/16/the-100-year-old-scientist-who-pushed-the-fda-to-ban-artificial-trans-fat/

I would agree that these blood lipids are moderately elevated. The one to pay attention to is the non-HDL-C, where the target should be < 130 mg/dL.

  1. It depends on how much saturated fat you tend to consume. It appears that there are some benefits to be had by reducing consumption down to about 10-11% of calories, but you don’t get much additional benefit beyond that (and this latter point tends to generate a lot of confusion when people look at the conflicting scientific evidence on the matter) Reduction in saturated fat intake for cardiovascular disease - PubMed . It also depends what you choose to replace those calories with Saturated Fats Compared With Unsaturated Fats and Sources of Carbohydrates in Relation to Risk of Coronary Heart Disease: A Prospective Cohort Study - PubMed and Dietary lipids and blood cholesterol: quantitative meta-analysis of metabolic ward studies. - ORA - Oxford University Research Archive

  2. Low-density lipoproteins are the cause of atherosclerotic cardiovascular disease. Low-density lipoproteins cause atherosclerotic cardiovascular disease. 1. Evidence from genetic, epidemiologic, and clinical studies. A consensus statement from the European Atherosclerosis Society Consensus Panel - PubMed and Impact of Lipids on Cardiovascular Health: JACC Health Promotion Series - PubMed . We have evidence of risk reduction when replacing saturated fat sources with unsaturated sources; although this benefit appears to be modest, we do not have evidence suggesting benefit to going in the other direction. We do not side with the “consensus” as a matter of fact, but rather try to evaluate the overall weight of the evidence. This is why it is foolish to radically change one’s opinion based on one paper, for example. If and when the overall weight of the evidence shifts, we will likely have to shift our opinion at that time as well. This would require a large body of prospective evidence showing decreases in cardiovascular risk / mortality from consuming increased amounts of dietary saturated fat above current estimates of risk thresholds, and increases in cardiovascular risk / mortality from consumption of unsaturated sources.

  3. I don’t know, maybe.