Why Saturated Fat Is Not The Problem

The thought of writing a paper has always intimidated me. Perhaps I’m just not thinking about it the right way, since I’ve typed e-mails that resemble editorials many times. This is a slightly post-edited e-mail to a friend whose cardiologist advised limiting saturated fats, while admitting that a high-carb diet may have lead to angina.

Why natural (minimally processed) fats are not likely to be a problem (when carbs are restricted, which by themselves can cause plenty of problems).

  • The fat in arterial plaque depends on what one eats, especially if one eats seed oils, so-called vegetable oils, which are high in omega-6 fatty acids. Here’s a quote from analysis of fat tissue and plaque fatty acid composition: “[strong correlation] between adipose tissue and plaque omega-6 polyunsaturated fatty acids (r = 0.89)” and no association between stored saturated fat and saturated fat in plaques. “These findings imply a direct influence of dietary polyunsaturated fatty acids on aortic plaque formation and suggest that current trends favouring increased intake of polyunsaturated fatty acids should be reconsidered.” (1)
    Take-away message:  might be best to minimize corn/soy/canola oils.
  • Basic biochemistry of fat metabolism (simplified): when insulin and blood sugar levels are low, fat is burned for energy. Both dietary fat, or fat released from fat cells gets converted to acetyl-COA in liver and other cells. Mitochondria then convert that acetyl-COA to energy, releasing water and CO2. When a lot of fat is liberated, there becomes a surplus of acetyl-COA in the liver. This surplus of acetyl-COA drives the production of ketone molecules, particularly beta-hydroxybutyrate. Ketones can cross the blood-brain barrier, providing an additional source of energy for the brain. This fills in gaps in glucose supply, suppressing hunger for long stretches between meals. Suppressing hunger is the often overlooked factor in weight maintenance.
  • Low levels of omega-3 (EPA and DHA) are associated with the formation of arterial plaques.
    “Patients with acute coronary syndrome had significantly lower levels of ω3 PUFAs (especially of EPA and DPA) than those without it.”  (2)
  1. Felton CV, Crook D, Davies MJ, Oliver MF. Dietary polyunsaturated fatty acids and composition of human aortic plaques. Lancet. 1994 Oct. http://www.ncbi.nlm.nih.gov/pubmed/7934543
  2. Amano T, Matsubara T, Uetani T, Kato M, Kato B, Yoshida T, Harada K, Kumagai S, Kunimura A, Shinbo Y, Kitagawa K, Ishii H, Murohara T. Impact of omega-3 polyunsaturated fatty acids on coronary plaque instability: an integrated backscatter intravascular ultrasound study. Atherosclerosis. 2011 Sep. http://www.ncbi.nlm.nih.gov/pubmed/21684546
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Backing into low-carb

In February 2014 I started limiting starchy foods and incorporating more savory foods: butter, eggs, cheese (esp. as snack food while at work), bacon, bacon grease to cook eggs with, etc.

I’ve never felt better.
In June, my blood test had triglyceride/HDL at .92

I have collected several journal articles, but I think lectures are a nice way to get started.  Mine first =)

So, as of January 2010, I was avoiding desserts except for special occasions, and not snacking after dinner.  My main motivation was to avoid going down the path of type 2 diabetes.

In February, I was lucky to catch an Alton Brown show called Live and Let Diet. He advocated certain vegetables be consumed daily and some weekly, included green tea, and avoidance of anything diet, and limiting pasta to once per week max.  By March I had given up diet soda (IBS went away), and in general was incorporating some of his advice. (Thank-you, Mr. Brown.)

In 2012-ish I heard an episode of People’s Pharmacy on NPR where they interviewed Gary Taubes about his book ‘Why We Get Fat’. He argued for sugar and starch being the cause of weight gain and that eating whole foods like chicken with the skin was better for us. I think I was thrown off by his accent. In hindsight, I should have checked out the book.

Late 2013, I was challenging the necessity of hunger while trying to maintain weight. Portion control vs. hunger.

Jan 2014, my boss told me of her nurse practitioner’s tip to watch these lectures:

Dr Robert Lustig’s “Sugar: The Bitter Truth”

(Taking on processed foods and high consumption of fructose — it’s a good educational piece about our recent food history and the biochemistry of fructose metabolism.)

and

Gary Taubes: ‘Why We Get Fat’
(at Santa Cruz)

I hunted down other Dr. Lustig talks and at the one in Oslo, he mentioned being at a low-carb forum. I remembered talk of low-carb a few years back, but it seemed to have gone quiet.

Here are the lectures I found next that helped build my LCHF perspective.
Dr Eric Westman –

Prof. Grant Schofield and Dr. Caryn Zinn –

Dr Peter Brukner, 2013 Low Carb Downunder – https://youtu.be/JMuD4Z-Oxys

Prof. Tim Noakes, Nov 2013 Paleo Runner podcast – https://youtu.be/iFxz7YFjycg

Postscript:  One of the Dr. Lustig talks I found was at AHS12.  He commented that there was another talk given at the same time and he was bummed out that he had to miss it.  I later tracked that talk down:  Insulin Signaling: Science and  Policy.  At about 42:45, moderator Eric Daniels concluded with the statement that `Take the moral high ground.  Back freedom of food choice.’