"What to Eat to Prevent a Stroke"
Strokes are one of the leading causes of death and disability in the world,
the most common cause of seizures in the elderly, and the second most
common cause of dementia, and a frequent cause of major depression.
In short, stroke is a burdensome, but preventable brain disorder.
According to the Global Burden of Disease Study, the largest study of risk factors
for human disease in history—funded by the Bill and Melinda Gates Foundation—
more than 90% of the stroke burden is attributable to modifiable risk factors,
though some are easier to modify than others. For example, about 10%
of all healthy years of life lost due to stroke may be due to ambient
air pollution. So yeah, I mean technically
that's a modifiable risk factor.
You could just move out of the city to some place with cleaner air,
but perhaps easier to just quit smoking, which accounts for 18%
of the stroke death and disability, about as much as diets high in sodium.
Diets high in salt are as bad as smoking when it comes to stroke burden,
but not as bad as inadequate fruit and vegetable consumption.
Yes, there's also other things like sedentary lifestyles,
which is not as bad as not eating enough whole grains,
but of the 89% of the stroke death and disability that's attributable
to modifiable risk factors, fully half appears to be due
to just not eating enough fruits and veggies.
Fruit and vegetable consumption is associated with lower risk
of about a dozen different diseases, and stroke is way up there.
There appears to be a linear dose-response relationship,
a straight-line relationship between more fruits and vegetables
and lower stroke risk, suggesting that the risk of stroke decreases
by 32% for every 200-gram increase in fruits—that's just like one apple a day—
and 11% lower risk for each equivalent amount of vegetables.
Particularly potent: citrus fruits, apples and pears,
and dark green leafy vegetables, one of which you can drink:
the green leaves of green tea.
Drinking three cups of green tea a day is associated with an 18% lower stroke risk.
But association doesn't necessarily mean causation. Have there ever been
any vegetables put to the test in randomized controlled trials?
Yes. Garlic is so potent you can stuff garlic powder into a capsule or compress
it into a tablet, so you can put it head to head against a sugar pill.
And garlic beat out placebo for the prevention of CIMT progression,
meaning the thickening of the major artery walls to the neck
going up to the brain, a key predictor of stroke risk—
continuing to worsen in the placebo group, but not the garlic group
that had been taking just a quarter teaspoon of garlic powder a day.
That would cost about a penny a day and just make your food yummier anyway.
OK, but has there ever been an interventional trial that's
actually followed people out to prove that a certain food reduced strokes?
Yes, nuts. The PREDIMED study showed that an ounce a day of nuts,
which is what I recommend in my daily dozen, cut stroke risk nearly in half.
But wait, PREDIMED? Wait a second, wasn't that the study that was retracted?
The PREDIMED trial is one of the most influential randomized trials ever, yet
in 2018 it was retracted only to be later republished, after making the necessary
corrections due to irregularities in their randomization procedures.
The original paper was withdrawn,
but in their re-analysis, they found the same results. The same 46% fall
in stroke risk in the added nuts group, dropping the 10-year risk of stroke
from about 6% down to 3%.
The good news is that stroke risk can be reduced substantially
by an active lifestyle, cessation of smoking and a healthy diet.
All we have to do now is educate and convince people
on the benefits that can be expected from a healthy lifestyle and nutrition.