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.