Take Care of Your Beta Cells and Perhaps Live Longer
Posted Apr 20 2009 12:36am
By Barbara Berkeley
The body is an incredibly complex mechanism. Just when we think we understand how one part works, another layer of signaling, hormones and pathways reveals itself. Like a child playing with a Matruschka doll, we open up one of the bodys’ mysteries only to find another one within. I say this because I am about to talk about insulin and I want everyone reading this to know that I fully realize that there are many other underlying layers to the story I am about to tell. Nevertheless, the hormone insulin – made by the Beta cells of the pancreas – continues to be implicated in an astonishing number of modern disease states. Take a look at any of our current health problems and likely as not you’ll find insulin lurking around acting suspicious.
For most of us, insulin comes to mind as the substance that diabetics lack, the stuff they need to inject. One of the easiest ways to make the connection between insulin and our recent health deterioration is to take note of the number of TV commercials that have suddenly appeared touting bright new “toys” for diabetics. We have a glut of these ads because developing diabetes is becoming so common that it’s almost a part of pop culture. These commercials make it seem like becoming a diabetic and testing blood sugar is actually fun. Your meter can be blue, purple or pink. It can even match your clothes. It’s easy! Painless!
Let’s start with a basic diabetes primer and the primer begins with this statement: diabetes is a destroyer and a killer. There’s not a thing that’s good about it.
Diabetes comes in two major forms: juvenile onset diabetes and adult onset diabetes. These also carry the names Type 1 and Type 2. Doctors have substituted the numbers for the old names because adult onset diabetes is no longer the province of adults. Thanks to all the starches and sugars we eat, it’s become common in kids too. So it’s more accurate to call it Type 2. The two forms of diabetes each come from a problem with insulin, but the source of the problem is different.
Normally, insulin is released by Beta cells when the brain senses that sugar levels are about to rise in the blood. Why would sugar levels go up? Usually because of something we’ve eaten. When we eat either starches or sugar, they are broken down into simple sugar molecules that enter the bloodstream. Insulin’s job is to keep sugar in the blood within a small, acceptable range. To do this, insulin takes sugar out of the blood and directs it into cells that can use sugar as fuel. But insulin has a second major job. It is also the body’s primary fat storage hormone. In a well-functioning body, insulin will decide how much sugar to send to the cells and how much to send into fat storage. The body will stay at normal weight because the insulin system is on auto-pilot.
So what happens to insulin in the two forms of diabetes? In Type 1 (more common in kids), something happens that destroys the Beta cells of the pancreas. This is usually an auto-immune process. For some reason, the body attacks its own Beta cells and destroys them. Type 1 diabetics have a total or almost total lack of insulin and must inject it to live. No one can survive without insulin because it controls the breakdown and storage of food.
Type 2 diabetics (more commonly adults, but increasingly kids as well) don’t have a problem making insulin…at least at first. Their problem is that some of the cells of their body have stopped listening to insulin. As a result, insulin can’t move sugar into the cells that would dispose of it. The unfortunate consequence is that the sugar is shunted into fat cells instead. There, it is transformed into fat and the person with the problem grows larger and larger. The brain recognizes that insulin is not working properly and asks the Beta cells to make excessive amounts in the hopes that the large volume of insulin will overwhelm the problem. This continual stress on the pancreas leads to Beta cell burn out. Over time, type 2 diabetics start looking more like type 1 diabetics. They lose a significant number of Beta cells and need medication or insulin injection to keep up.
Because Beta cell destruction is so common and so important, I have a real problem with the diagnosis of “Pre-Diabetes.” Patients who are told that they are “Pre” diabetic or simply have “abnormal” blood sugar need to know that we doctors don’t have a good handle on when diabetes begins. There is no “pre.” It’s all a continuum. What we do know, is that once blood sugar has started to become abnormal, a marked loss of Beta cells has already occurred and that these Beta cells can’t be resurrected. How much of a loss are we talking about? Read the following from a diabetes text book:
“A study of pancreatic tissue obtained from autopsies demonstrated that obese humans with impaired fasting glucose (110-125 mg/dl) had a 40% decrease in relative beta cell volume, and obese humans with type 2 diabetes had a 63% decrease in relative beta cell volume.” ( Clinical Diabetes, Fonseca )
This simply means that those people we call Pre-Diabetic are already well on the road to losing almost half of their vital Beta cells. What’s “pre” about that??
When we talk about taking care of ourselves, we always mention eating less fat, exercising more, stressing less. What about taking care of a vital and unappreciated asset? Our Beta cells. Forget about the stress on us! Let’s try taking the stress off them! This is easily accomplished when we eat fewer foods that turn into sugar in the bloodstream.
Apart from staving off diabetes, there may be another reason to be awfully nice to our Beta cells. As it turns out, insulin appears to be a kind of super-hormone with vast areas of responsibility that go beyond simply controlling sugar and fat. The April 9th issue of Nature features an article on life extension through caloric restriction. As I’ve written previously, animals who are fed calorie restricted diets live longer and appear younger than controls. Accumulating evidence points to beneficial effects in humans as well. Now it appears that insulin plays a role in this process. In rodents who have been implanted with human tumor cells, cancer growth has been stopped by dietary restriction. It appears that the tumors continue to grow when insulin is around, but stop growing when insulin stops signaling them. It has also been noted that certain tumors that do not respond to restricting calories. When these particularly cell lines were investigated, researchers found that the tumor itself had developed a mutation that continued to signal cells just as if insulin were still present. Thus, the tumor continued to grow. Anne Brunet of Stanford University writes in Nature:
“Dietary restriction can prolong life and delay the onset of cancer. Suppressing the signaling pathway that is mediated by the hormone insulin might be crucial for the anticancer effects of reduced caloric intake….Moreover, involvement of the insulin-mediated pathway indicates that drugs that ameliorate insulin resistance in type 2 diabetes might be beneficial in preventing cancer, even in non-diabetic patients.”
The study of insulin and its role in life extension and tumor growth is still in its early stages, but once again, what is known seems consistent with my personal belief that diets that stimulate less insulin production are healthier. I believe that this is of particular importance for those who are overweight or who have been so. Many of these people are insulin resistant, meaning that their bodies are making inappropriately large doses of insulin to compensate for the problem. As we have seen, Big Insulin is not a good thing.
I know your self-care list is a long one, but I’d like to put in a plug for kindness to your Beta cells. They are the underappreciated workhorses of your body and are central to your health. When they start dying or overproducing insulin, you are in trouble. To quickly and simply cut your risk, lose belly fat so that your muscle cells are not resistant and insulin works better. This will cut the amount of insulin you make. Then, eat minimally from the starch and sugar group so that insulin gets the rest it deserves. Who knows, the vacation you give these mysterious cells may even lead to fewer worries about cancer and a longer life!