Some of the best sources of catechins are tea, beans, berries, and apples.

In July, I wrote about a new study that found eating apples, drinking tea (black or green), or consuming other foods that contain epicatechin could reduce the risk of heart disease, stroke, and other vascular-related deaths. The authors of that study said something interesting:

In a double-blind crossover randomized control trial (RCT), we showed that pure epicatechin improved insulin resistance.

Here’s the study they were referring to:
Effects Of The Pure Flavonoids Epicatechin And Quercetin On Vascular Function And Cardiometabolic Health: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial, American Journal of Clinical Nutrition, February 2015

That first study about epicatechin and heart disease was a population study. This one was an intervention. Smaller but in a way more telling. Is it really the epicatechin? Or some other health-promoting behavior? What if you extracted epicatechin and gave it to people as a supplement? That’s what they did, and found:

Epicatechin supplementation improved fasting plasma insulin and insulin resistance.

They gave a 100 mg pill. That’s a lot of epicatechin. But if all your food had a little bit, you could easily surpass 100 mg in a day.

I’m not big on supplements, even though I just wrote that everyone over 50 should be taking vitamin B12. Eating the food that contains the chemical is, for reasons I’ve detailed over the years, more effective and cheaper than taking a pill. There are additional benefits in food, like fiber. In this case, since epicatechin is a flavonoid, and flavonoids are only found in plants, eating a diet that contains a lot of plants might improve symptoms and complications of diabetes, if not prevent them altogether (depending on what other foods a person ate). This may be one reason why vegetarians have a “nearly one-half reduction in risk of type 2 diabetes” compared with nonvegetarians.

A few more excerpts from the study:

[There is a] short elimination half-life of epicatechin (2 hours).

So, eating a little bit every 2 hours is probably better than taking a once-a-day pill. Also, we absorb more of a small dose than we do a large dose.

The response to epicatechin may be stronger in subjects with impaired fasting glucose concentrations and higher levels of insulin resistance.

Speaks for itself.

By studying pure flavonoids, we excluded potential interactions with other flavonoids and compounds in cocoa/tea. It is possible that such interactions play a role in the effects of cocoa and tea.

Another reason why it’s better to get epicatechin from food instead of a pill. This is true for many isolated, concentrated compounds.