Healthy carbs for DM patients

[Guest guest]

Here is an article from Diabetes Self Management directing readers to opt for

starches that reach the distal ileum to stimulate GLP-1 which triggers the beta

cells to produce insulin.

Best choices: corn kernels, oats, berries, broccoli and collard greens. Note:

whole wheat and standard fruits and veggies do not routinely reach the ileum and

are therefore not recommended according to this article.

Any RDs teaching this concept to DM patients?

http://www.diabetesselfmanagement.com/blog/david-spero/are-there-any-good-carbs/\

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Are There Any Good Carbs?

Spero

July 20, 2011

Refined carbs, bad; whole carbs, good. Diabetes educators and nutritionists have

repeated that saying for years. Low-carb advocates say they’re wrong, that

almost all carbohydrates are bad. Who’s right? Are whole carbohydrates really

good for us, and how whole do they have to be?

To answer this, we have to know more about carbohydrates and more about

diabetes. In particular, we have to learn about insulin signaling. As we know,

people with diabetes have trouble dealing with sugars and foods that break down

into sugar. Some people can’t produce enough insulin, as in Type 1, LADA,

often called Type 1.5, and MODY. For others, their insulin signaling systems are

not working, which is usually called Type 2. This could mean that the beta cells

are not receiving signals to produce insulin, or that the muscle cells and liver

are not getting signals to cooperate with the insulin.

This failure of muscle and liver cells to cooperate is called insulin resistance

(IR). We used to think that the beta cells wore themselves out trying to

overcome IR. Then they would fall behind, start to die, or fail to produce, and

you would be left with Type 2 diabetes.

But now it appears that beta cells are not “wearing out.†They are either

being damaged, or they are not receiving the signals they need to grow and to

start producing insulin.

Like all other cells in our body, beta cells only know what to do because

chemical messengers, produced by other cells, tell them. There are thousands of

these messengers, and many are still undiscovered. One key messenger is GLP-1 or

glucagon-like peptide-1. As I explained last month — please reread that blog

entry if you’ve forgotten — GLP-1 is produced by glands at the far end of

the small intestine, in the distal ileum. These glands produce GLP-1 mainly when

stimulated by the presence of carbohydrates.

The problem is that modern carbohydrates never reach the distal ileum. They are

absorbed before they get there, so the gut glands don’t produce GLP-1. Without

this messenger, beta cells don’t know to produce insulin. They also don’t

reproduce as fast. GLP-1 also slows the rate at which glucose (and other

nutrients) is absorbed from the gut, so without it, you will get big spikes in

your blood glucose level as all the carbs come in at once.

GLP-1 is so valuable that a new class of expensive drugs, the incretin mimetics,

are being prescribed to make up for it. The main ones are exenatide (brand name

Byetta) and liraglutide (Victoza). They act like GLP-1, stimulating insulin

production (but only in the presence of glucose), slowing glucose absorption,

stimulating beta-cell reproduction, and keeping the liver from releasing glucose

into the blood.

Good stuff. But there are side effects, considerable expense, and they’re

still not as good as the real thing. What people with Type 2, and probably other

types, can do is limit carbohydrate intake to mostly carbohydrates that will

actually reach the distal ileum and stimulate GLP-1 (and related chemical

messengers that we might not know about yet.)

What Carbs Can Stimulate the Distal Ileum?

So now that we know what we’re trying to do, what foods could do it? Are whole

grains the answer? Our beloved nutritionist Amy said about whole grains

in 2008: “Whole grains contain three layers: bran, endosperm, and germ…

Refined grains (think white flour and white rice) have the bran and germ layers

removed.â€

It certainly sounds like whole grains would stay in the gut longer. But even

whole-grain flours get into your bloodstream much faster than the old, natural

roots, fruits, and leaves. They often get absorbed as fast as the refined ones.

That’s because they’re ground up, so it’s easier for digestive juices to

get to them, break them down, and absorb them.

As a result, the only really whole grains are probably those you eat right off

the plant, or close to it, like corn on the cob or brown rice. Any grains that

are ground into flour or blended into processed food likely won’t reach the

distal ileum.

If grains and sugars don’t reach the distal ileum, don’t trigger GLP-1, and

therefore can’t be well used by our bodies, what about vegetables and fruits?

Well, big chunks of starch in the form of starchy vegetables (like carrots or

squash), probably won’t reach the distal ileum either. Green vegetables,

especially fibrous ones, like broccoli, kale, collard greens, and cabbage, are

the vegetables most likely to make it to the distal ileum. (Although, see a big

list of nonstarchy vegetables here .)

Likewise with fruits. Modern fruits like humongous commercial apples, pears, and

peaches also get into the bloodstream far too fast to stimulate GLP-1. Berries

are better (and I’m not talking about these quarter-pound strawberries you see

now. Smaller ones are best.) You can see a big list of nonstarchy fruits here.

Bottom line — if you have Type 2 (and this probably applies to some people

with other types), I think these slow-absorbing, high-fiber carbohydrates can be

part of your diet, and might even be healing to your insulin-signaling system.

But be aware that many foods that call themselves “whole†or

“whole-grain†are not that whole. They’re just slightly less processed.

The real whole grains are the ones you can see — the kernels of corn or rice,

or oats. Note that these three grains are also gluten-free.

But even those “good†whole grains should be eaten in moderation. And

please, don’t forget the plusses of vinegar, which appears to have some of the

same benefits as GLP-1.

**

If you want an inspirational read, see my blog entry on the art of “Helping

without Helpingâ€.

Osowski MS, RD, LD

Registered Dietitian