Peter Dobromylskyj is a UK-based veterinary anaesthetist and nutrition blogger whose blog Hyperlipid is amongst the longest-running and most highly respected in the low-carb and ancestral health communities. Peter has been writing about the biochemistry of nutrition since 2006, and has authored over 800 posts aimed at reviewing, analysing, and interpreting nutrition literature. Given his outside-the-box thinking and unconventional approach to metabolism and health, Peter’s work has amassed a large and devoted following.

Today, NBT Scientific Director Megan Hall interviews Peter to talk about insulin resistance, including the factors that cause it and why the condition is actually physiologically adaptive. Peter compares dietary saturated fats to polyunsaturated fatty acids (PUFAs), and explains why the scientific literature can be misleading when determining which truly promotes health. He gives specific science-based recommendations for how much PUFA to include in your diet, and also offers advice on what to feed your pets.

For additional resources on insulin resistance and the influence of dietary fat sources, be sure to see the outline Megan wrote to prepare for this podcast.

Here’s the outline of this interview with Peter Dobromylskyj:

[00:01:52] Insulin resistance is physiologically adaptive.

[00:02:23] Reactive Oxygen Species (ROS) as signaling molecules.

[00:04:52] Dr. David Speijer, Researcher at the University of Amsterdam.

[00:05:31] Dr. Nick Lane, Professor of Evolutionary Biochemistry.

[00:11:29] Protons thread on the Hyperlipid blog.

[00:22:58] When insulin sensitivity becomes insulin resistance.

[00:30:37] How long it takes to become insulin resistant.

[00:34:55] Acipimox reduces free fatty acid circulation and temporarily reverses insulin resistance; 1. Santomauro, A. T., et al. "Overnight lowering of free fatty acids with Acipimox improves insulin resistance and glucose tolerance in obese diabetic and nondiabetic subjects." Diabetes 48.9 (1999): 1836-1841; 2. Aday, Aaron W., et al. "Impact of Acipimox Therapy on Free Fatty Acid Efflux and Endothelial Function in the Metabolic Syndrome: A Randomized Trial." Obesity 27.11 (2019): 1812-1819.

[00:36:19] Effects of caffeine on insulin resistance.

[00:37:34] Phil Maffetone.

[00:38:25] In mice, stearic acid reduces visceral adipose tissue; Study: Shen, Ming-Che, et al. "Dietary stearic acid leads to a reduction of visceral adipose tissue in athymic nude mice." PLoS one 9.9 (2014): e104083.

[00:38:34] Overfeeding studies in humans: 1. Rosqvist, Fredrik, et al. "Overfeeding polyunsaturated and saturated fat causes distinct effects on liver and visceral fat accumulation in humans." Diabetes 63.7 (2014): 2356-2368; 2. Iggman, David, et al. "Association of adipose tissue fatty acids with cardiovascular and all-cause mortality in elderly men." JAMA cardiology 1.7 (2016): 745-753.

[00:44:10] Raphael Sirtoli’s Podcast: Carnivore Cast.

[00:45:02] Butter fat → higher postprandial levels of FFAs and triglycerides; Study: López, Sergio, et al. "Distinctive postprandial modulation of β cell function and insulin sensitivity by dietary fats: monounsaturated compared with saturated fatty acids." The American journal of clinical nutrition 88.3 (2008): 638-644.

[00:46:50] Tucker Goodrich.

[00:47:38] How much polyunsaturated fat is needed to cause metabolic dysfunction?

[00:48:27] Leptin-deficient mouse study: Reeves, Valerie Lynn. "A diet enriched in stearic acid protects against the progression of type 2 diabetes in leptin receptor deficient mice (DB/DB)." (2012).

[00:49:57] Aim for 2-4% of calories from linoleic acid (over 8% is obesogenic).

[00:51:26] Efforts to lose weight with unsaturated vs. saturated fat stores.

[00:53:29] Animal based keto with 15% polyunsaturates; Study: Hall, Kevin D., et al. "Effect of a plant-based, low-fat diet versus an animal-based, ketogenic diet on ad libitum energy intake." Nature Medicine 27.2 (2021): 344-353.

[00:58:46] Electron transport chain (see this figure) and mitochondria.

[00:58:57] Summary so far.

[01:01:33] What dogs/pets should be eating.

[01:09:05] Labradors may have problems with leptin signaling; Book: Raw Meaty Bones Promote Health, by Tom Lonsdale.