Glycemic response to fava beans

Open broad bean pods.

The glycemic response to fava beans at first glance is surprisingly high.

High GI foods cause a rapid rise in blood glucose, with a corresponding squirt of insulin from the pancreas required to contain and avert this threat to the linings of blood vessels. Should we be unable to produce the hormone (type 1 diabetes) or have become resistant to it (T2DM) then our capillaries will be damaged and become inflamed; that is why diabetics lose toes, go blind and suffer from heart attacks and strokes.

Clearly if we value our lives we need to avoid highly glycemic foods; are fava beans among them?

The answer is a yes and a no. Like most other foods it all depends on how you refine, prepare and cook them. Whole grain wheat and rice are not highly glycemic, but most of that bought from the supermarkets today is downright dangerous for our health.

I find it very interesting that neither my chickens or dogs, nor the creepy crawlies in my worm farms will touch white bread; nor will you find weevils in refined flour. Only humans will eat it.

Generally speaking legumes have a very low glycemic index; the carbohydrate in them is released very slowly into the blood stream, making them an ideal source of starch for energy. Also, the protein found coupled with the carbs in them lowers the GI even further. So why do broad beans have such a high GI?

Do broad beans have a high GI?

No, they do not, if you enjoy them the way nature prepares them. The problem is that they go soft very quickly after reaping so, if you can get them at all, you will find that farmers let them grow old and then the cook is expected to do a double podding.

First you must remove the outer shell, as shown above, then you must cook them and by gently squeezing the bean squirt the inner core out of its little sheath; then what remains is certainly highly glycemic. 

The only solution is to grow broad beans yourself, reap them young and tender and cook immediately with the outer shell and inner pod, just like you would a pole or bush bean.

So why eat them then if it is so much trouble? Because firstly, they have the greatest amount of vegetable protein of all the legumes, and secondly because they are the only significant source of L-Dopa. That is a very important resource for the body to synthesise an essential neurotransmitter called dopamine. Have you heard of Parkinson's disease? Grow and enjoy broad beans.

Young whole broad beans in their pods are also very delicious. Those that are double-podded are highly glycemic; they have lost most of their fibre and much of the L-dopa.

Three forms of broad beans.

Top: Whole broad beans

Shelled broad beans

Double podded broad beans - this is the way modern cooks would have you eat them.

Bottom: Empty pods

Broad bean bruschetta.

Broad beans on toast is a great favourite and takes at most ten minutes to put together; add five more if you know how to plant broad beans.

Glycemic response to fava beans

Glycemic response to fava beans is warped because tests are done after the fruit is first podded and then popped out of its skin; most of the fibre is removed.

Allowing the beans to grow old so that you have to remove the tough outer skin is just a bad practice. Like all veggies they are much nicer when young and freshly picked.

And it is bad nutrition too; having popped the old beans out of their skins they now create havoc with your blood glucose; in scientific jargon they have a really quite large glycemic response.

So perhaps you just love them and so enjoy dishes like these, but if you are interested in going into the subject more deeply then this fava beans nutrition link will inspire you. Just don't double-pod them.

When to pod fava beans

Stringing fava beans.

As stated above much of the important nutrient of fava beans is to be found in the pod; also the fibre without which the glycemic index rises. However they do reach a point where the skin can become unpleasantly tough and fibrous.

I have simple rule of thumb. String each bean and, if it produces a string, then pod it, removing the beans and discarding the pod. If however it produces no string, then I slice the whole bean and include the pod in the dish that I am cooking.


Our newsletter is entitled "create a cyan zone" at your home, preserving both yourself, your family and friends, and Mother Earth for future generations. We promise not to spam you with daily emails promoting various products. You may get an occasional nudge to buy one of my books!

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  • Mill your own flour
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  • Microplastics from our water
  • Alternative types of water storage
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  • What can go in compost?
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