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Plant-based diets are associated with a lower risk of cardiovascular disease, mortality, and dying from all causes put together. This study of a diverse sample of 12,000 Americans found that “progressively increasing the intake of plant foods by reducing the intake of animal foods may be associated with beneﬁts on cardiovascular health and mortality…”, but when it comes to plant-based diets for cardiovascular disease prevention, all plant foods are not created equal. Were the vegetarians in the British study that found the higher stroke risk just eating a lot of vegan junk food?
Any diet devoid of certain animal food sources can be claimed to be a vegetarian or vegan diet; so, it’s important to see what they’re actually eating. One of the first things I look at when I’m trying to see how serious a population is about healthy eating is look at something undeniably, uncontroversially bad: soda, liquid candy. Anyone drinking straight sugar water obviously doesn’t have health, top of mind. In the big study of plant-based eaters in America, where people tend to cut down on meat for health reasons far more than ethics… flexitarians drink fewer sugary beverages than regular meat-eaters, as do pescatarians, vegetarians, and vegans.
In the UK study, though, where the increased stroke risk was found, where folks are more likely to go veg or vegan for ethical reasons, the pescatarians are drinking less soda, but the vegetarians and vegans are drinking more. I’m not saying that’s why they had more strokes; it just might give us an idea of how healthy the people were eating. In the UK study, the vegetarian and vegan men and women were eating about the same amount of desserts, cookies and chocolate, and about the same total sugar. In the U.S. study, the average nonvegetarian is nearly obese, even the vegetarians are a little overweight, and the vegans were the only ideal weight group. In this analysis of the UK study, though, everyone was about the same weight—in fact the meat-eaters were skinnier than the vegans. The EPIC-oxford study seems to have attracted a particularly health conscious group of meat-eaters weighing substantially less than the general population.
Let’s look at some particular stroke-related nutrients. Dietary fiber appears beneficial for the prevention of cardiovascular disease including stroke, and it appears the more the better. Based on studies of nearly a half a million men and women there doesn’t seem to be any upper threshold of benefit; so, the more, the better. More than 25 grams of soluble fiber, 47 grams of insoluble dietary fiber and you can really start seeing a significant drop in associated stroke risk; so, one could consider these as the minimal recommendable daily intakes to prevent stroke at a population level. That’s what you see in people eating diets centered around minimally processed plant foods. Dean Ornish got up around there with his whole food plant-based diet. Maybe not as much as we were designed to eat, based on the analyses of fossilized feces, but that’s the kind of neighborhood where we might expect significantly lower stroke risk. How much were the UK vegetarians getting? 22.1. Now, in the UK they measure fiber a little differently; so, that may actually be closer to 30 grams, but not the optimal level for stroke prevention. So little fiber that the vegetarians and vegans only beat out the meat-eaters by about 1 or 2 bowel movements a week, suggesting they were eating lots of processed foods.
The vegetarians were only eating about a half serving more of fruits and vegetables, thought to reduce stroke risk in part because of their potassium content, yet the UK vegetarians at higher stroke risk were evidently eating so few greens and beans they couldn’t even match the meat-eaters, not even reaching the recommended minimum daily potassium intake of 4700 mg a day.
And what about sodium? The vast majority of the available evidence indicates that elevated salt intake is associated with higher stroke risk. There’s like a straight-line increase in the risk of dying from a stroke the more salt you eat. Even just lowering sodium intake by a tiny fraction every year could prevent tens of thousands of fatal strokes. Reducing sodium intake to prevent stroke: time for action, not hesitation, but the UK vegetarians and vegans appeared to be hesitating, as did the other dietary groups. All groups exceeded the advised less than 2400 mg daily sodium intake—and that doesn’t even account for salt added at the table, and the American Heart Association recommends under just 1500 a day; so, they were all eating lots of processed foods. So, no wonder the vegetarian blood pressures were only 1 or 2 points lower; high blood pressure is perhaps the single most important modifiable risk factor for stroke.
What evidence do I have that if the vegetarians and vegans ate better their stroke risk would go down? Well, in rural Africa where they were able to nail the fiber intake that our bodies were designed to get by eating so many whole healthy plant foods— fruits, vegetables, grains, greens and beans, their protein almost entirely from plant sources, not only was heart disease, our #1 killer, almost non-existent, so apparently, was stroke, surging up from out of nowhere with the introduction of salt and refined foods to their diet.
Stroke also appears to be virtually absent in Kitava, a quasi-vegan island culture near Australia whose diet was very low in salt and very rich in potassium, because it was a vegetable-based diet. They ate fish a few times a week, but the other 95% or so of their diet was lots of vegetables, fruits, corn and beans, and they had an apparent absence of stroke, even despite their ridiculous rates of smoking. After all, we evolved eating as little as like less than an 8th of a teaspoon a day of salt and our daily potassium consumption is thought to have been as high as like 10,000 mg. We went from an unsalted, whole-food diet to salty processed foods depleted of potassium whether we eat meat or not.
Caldwell Esselstyn at the Cleveland Clinic tried putting about 200 patients with established cardiovascular disease on a whole food plant-based diet. Of the 177 that stuck with the diet only one went on to have a stroke in the subsequent few years compared to a hundred-fold greater rate of adverse events—including multiple strokes and deaths in those that strayed from the diet. “This is not vegetarianism,” Esselstyn explains. Vegetarians can eat a lot of less-than-ideal foods. This new paradigm is exclusively whole food, plant-based nutrition.
Now this entire train of thought, that the reason typical vegetarians don’t have better stroke statistics is because they’re not eating particularly stellar diets, may explain why they don’t have significantly lower strokes rates, but that still doesn’t explain why they may have higher stroke rates. Even if they’re eating similarly crappy, salty, processed diets at least they’re not eating meat, which we know increases stroke risk; so, there must be something about vegetarian diets that so increases stroke risk that it offsets their inherent advantages? We’ll continue our hunt, next.
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