The Other Thing Coffee Does To Your Blood Sugars

When it comes to coffee and blood sugars, let’s first mention that we’re talking about unsweetened black coffee today.

There is a difference between that and a double-chocolate arianne grande mocha frappuccino with an extra shot of caramel.

For how different ways of taking it affect blood sugars differently, see: Coffee, From A Blood Sugar Management Perspective

But for today, our coffee with be tall, dark, and handsome. Or small and bitter but also hot. Or however you like it, provided it’s black and unsweetened.

So, with that in mind…

Coffee’s multiple antidiabetic effects

It has previously been established that coffee improves insulin resistance for women (not for men!).

A large (n=7,453) study of people aged 19–64 examined coffee-drinking habits and insulin sensitivity, looking at markers including the homeostasis model assessment of insulin resistance (HOMA-IR).

For the women in the study:

• One cup of black coffee daily reduced HOMA-IR and fasting insulin by 26% and 21%, respectively.
• Two cups of black coffee daily were linked to a 23% lower risk of elevated fasting insulin or HOMA-IR.
• Two or more cups of black coffee yielded a 27% and 36% reduction in HOMA-IR and fasting insulin, respectively.

For the men in the study:

• In men, no significant associations with glucose metabolism markers were observed. Sorry.

For those enjoying cream/sugar in their coffee:

• In those consuming coffee with sugar and/or cream, no significant associations with glucose metabolism markers were observed.

You can read that paper here: Association Between Coffee Consumption and Glucose Metabolism Markers in Korean Adults

Now, the new news!

Researchers (Dr. Chenxi Quan et al.) identified six previously unknown diterpene esters in roasted coffee that strongly inhibit α-glucosidase, an enzyme central to post-meal blood sugar spikes.

In other words, inhibiting α-glucosidase can slow down carbohydrate digestion and thus slow down glucose absorption and thus slow down blood sugar spikes (making them not spikes at all, but rather flattened curves).

As for how effective this is, in numbers: three of the newly-named (but, we must admit, not very creatively-named) molecules, caffaldehydes A, B, and C, had IC₅₀ values* of 45.07, 24.40, and 17.50 μM, making them more potent in lab tests than popular diabetes drugs.

*Some quick notes so that the above isn’t useless technobabble:

An “IC₅₀ value” refers to the half maximal inhibitory concentration, which is a standardized way scientists measure how potent a substance is at blocking a biological process.

• How it works: the concentration of a compound needed to inhibit 50% of a specific biological activity, such as an enzyme’s action, under defined laboratory conditions.
• How to understand it: a lower IC₅₀ means stronger inhibition because less of the compound is required to achieve the same effect.

Now everyone can understand it, here’s the paper: Bioactive oriented discovery of diterpenoids in Coffea arabica basing on 1D NMR and LC-MS/MS molecular network

Another reason to enjoy a cup or three of coffee!

Want to learn more?

Check out:

The Bitter Truth About Coffee (or is it?) ← for a more general overview of coffee and health

Enjoy!