"Benefits of Beans for Peripheral Vascular Disease"
Legumes, by which they mean all kinds of
beans, chickpeas, split peas, and lentils,
are an excellent source of many essential
nutrients—vitamins, minerals, fibers,
antioxidants, and not just an excellent source,
perhaps the single cheapest source.
In terms of nutrition density per penny,
the four that really pull off
from the pack are pinto beans,
lentils, black beans, and kidney beans.
And, all that nutritional quality
may have beneficial effects on
excess body weight, insulin resistance,
high cholesterol, inflammation,
and oxidative stress—
all major cardiovascular risk factors.
So, do men and women who eat more
beans tend to have less heart disease?
Yes, suggesting that increasing
legume intake may be an important part
of a dietary approach to the primary
prevention of coronary heart disease
in the general population,
meaning prevention of heart disease
in the first place.
But, maybe those eating more
bean burritos are just eating
less beef burritos?
They took that into account,
controlling for meat intake,
fruits, and vegetables and smoking and exercise,
and still, the bean eaters
appeared to be protected.
Note the highest category here was eating
legumes 4 or more times a week.
In my Daily Dozen, I recommend people
eat legumes three times—a day!
In Costa Rica, they were able to find
enough people eating beans every day,
and so, even after controlling for
many of the same things,
like intake of saturated fat and cholesterol,
one bean serving a day was
associated with a 38% reduction
in the risk of heart attack.
Yeah, but do you actually
get to live longer too?
Yes, apparently so, an 8% lower all-cause mortality,
again after adjusting for other dietary factors.
You can’t control for everything, though.
You can’t really prove cause and effect until you…
put it to the test.
Randomized controlled interventional trials
have found that dietary bean intake
does significantly reduce
bad cholesterol levels,
dating back a half century to 1962.
Measure cholesterol levels at baseline,
and then add beans to their diet,
and then remove beans from their diet.
And, look, beans have a low glycemic index
and saturated fat content,
and are high in fiber,
potassium, and plant protein,
each of which independently confers
blood pressure-lowering effects.
But, whether there’s sufficient evidence
to emphasize beans alone to lower BP is unclear.
Therefore, what we need is a
systematic review and meta-analysis
of controlled feeding trials and...
here it is.
And, what they found is that beans
do indeed lower blood pressure
no matter where you start out.
OK. So, beans may be able
to prevent artery disease,
but what about reversing it?
Can the daily consumption of beans—
other than soy,
reverse vascular impairment
due to peripheral artery disease?
Peripheral artery disease results
from a decrease in blood flow
to the legs due to a buildup
of atherosclerotic plaque higher up.
Yeah, soybeans may help,
but what about other beans?
So, they had twenty-six individuals
with peripheral artery disease
consume one serving a day of a combination of beans,
split peas, lentils, and chickpeas for 8 weeks.
Basically, how you diagnose and follow-up the disease
is with the ankle-brachial index,
which is just the ratio of
blood pressure at your ankle
compared to your arm.
Once it dips below point nine,
that means you must have some kind
of clogs in blood flow to your lower body,
but eat some beans,
and you may get a significant increase,
enough to push four of 26 participants
up into the normal range
after just 8 weeks, eating some beans!
Now, there was no control group,
but people tend to get worse, not better.
The researchers conclude
a legume-rich diet can elicit major
improvements in arterial function.