THIS IS NOT MEDICAL ADVICE
Over the past couple years, I 've talked (and argued) with a number of vegans on social media, and while I’ve found their arguments lacking, there was one thing I could not explain: Why aren’t vegans fat?
I ran that question by a number of well informed people and didn’t get a satisfactory answer. By our theories of insulin driven obesity, it would seem that these high carb vegans should be fat, or at least chubby, but they aren’t. Some claimed it was because vegans were so malnourished they were digesting their own bodies, others that it had to do with the Randle Cycle (competition between carbs and fatty acids) because, they claimed, vegans eat a very low fat, low to moderate protein, high carb diet.
Neither of these seems to hold water. There are plenty of examples, for instance, of vegan gym rats who eat a whole foods vegan diet with copious supplementation of vegetable based protein powders who maintain a body composition similar to their keto or paleo counterparts. The Randle Cycle briefly satisfied my question until I found many examples of low BMI vegans who eat moderate fat diets. Many get a lot of fat in the form of nut butters as a primary protein source for instance. This latter example really interested me because Americans, in the 60s, 70’s and into the 80’s, could eat a large amount of fast food combining fat & carbs and didn’t tend to get obese until something started to change in the later 1980s / early 1990s.
So, I started doing a little observational research on what and how vegans eat.
Q: How do you starve a vegan?
A: You take away the blender.
The joke is funny because it’s true. If you pull up any number of vegan “what I eat in a day” videos, they almost all start with the morning smoothie made from a variety of fresh, raw vegetables (or alternatively freeze dried vegetable powders), mostly with a base of leafy greens and the addition of some fresh fruit, soy milk or fruit juice and occasionally some seeds or nut butters.
Notably here, these are FRESH vegetables, not cooked. That means these vegans are taking in HUGE amounts of Nitric Oxide (NO) along with some very key micronutrients, in particular beta carotene, C, D3 (fortified fake milks), K1, Mg, Zn, etc…) Dietary nitrates in the leafy greens tends to be destroyed by cooking apparently & while the nutritional content of our foods tends to have been reduced via soil depletion, it seems these vegans may be making up for that by sheer volume, takin in fresh vegies from a fire hose, along with the dietary nitrates.
Why is this important? There are ample studies out there linking Insulin Resistance (IR) to any number of micronutrient deficiencies. Most people eating SAD are fat and deficient in multiple of these micros. That didn’t explain the slender high carb vegans however, because if it were only the micros, then anyone eating SAD that takes a multi-vitamin would get similar improvements in IR and drop body fat, which obviously is not the case. Most of the micros do, however have a supporting role with respect to Nitric Oxide (NO)!
NO is a signaling molecule in the body involved in a lot of processes and doesn’t seem to be particularly well understood. It is known to be a vascular dilator and to have a role in IR however.
NO is produced in one of four ways:
- eNOS (conversion of L-Arginine, to NO and L-Citrulline by endothelial cells)
- Dietary Nitrates.
- Sun exposure.
- Exercise.
I did find some rat studies which indicate heated and reheated refined vegetable oils disrupt eNOS and result in heart disease! NOTE: while I tend to be skeptical of rat and mouse studies with a ketogenic diet since rats and mice are difficult to keep in ketosis, I’m less skeptical about studies with such oils.
This made me raise an eyebrow because around the time people in the USA began getting REALLY REALLY FAT, fast food chains also made the switch from frying in beef tallow to refined vegetable oils! A little more research told me that high blood glucose also tends to attack and damage endothelial cells, further reducing the amount of available NO. Also, inflammation response (veg oils & sugar) robs the body of available NO as well.
Low NO results, in part, in a back-up of insulin in the body. Since endothelial cells can’t produce enough NO, insulin can’t move as effectively into interstitial space and supply cells. Higher long term insulin levels => IR. NO is also involved in mitochondrial biogenesis (along with our old friend Magnesium). Mitochondrial dysfunction is part of IR. Healthy & plentiful mitochondria are part of a healthy metabolism and metabolic flexibility.
Dietary nitrates from vegetable sources, as it turns out, can easily make up for MORE THAN the total amount of NO made via eNOS in a single day.
On sun exposure, notice also that starting around the same time that obesity started to climb in the USA, the fear of sun related skin cancers resulted in use of sunscreen or sun avoidance. This removed a supplemental source of NO. Correlation does not equal causation, but it’s interesting.
A lot of these other micronutrients perform a supporting part in NO production, and keeping it from breaking down quite so quickly, but Beta Carotene appears to perform a very specific independent role in IR. It supports the clearance of insulin from our bloodstream! It does not appear that Retinol preforms the same function or can be substituted for Beta Carotene in this case. Clearing insulin from the blood is likely just as important as reducing insulin production in the first place.
What does this all mean to me? Our understanding of IR is incomplete and perhaps, minimizing carbs & oxalates in the diet at the expense of raw vegetables rich in nitrates and micronutrients (such as spinach, arugula, kale, cabbage, broccoli, carrot…) and certain lower carb fruits like strawberries, is wrongheaded and even somewhat counterproductive if our goal is to improve/optimize metabolic health.
P.S. There’s a vegetable called “red spinach” which is really a form of amaranth that is VERY HIGH in dietary nitrates and is said to have ZERO oxalates. I have no idea if it has an appealing flavor but it’s out there.
P.S.S. Nitric Oxide has been shown to inhibit viral replication of Covid-19.
P.S.S.S. I have been away from the forum for a while due to completing a Masters degree in Engineering. I’ll try not to be such a stranger.
I would do LCHF veganism, obviously. If I would do veganism what I won’t. As a HCLF vegan? I would die of hunger in a few months if I wouldn’t kill myself before. Low-fat is something I never tried and never will.
