Saturday, April 25, 2020

Insulin Sensitivity in the Brain

We all know people who go on a diet, lose weight, and manage to keep it off. Others go on a similar diet, lose a little weight, and then regain it all, often ending up heavier than when they started.

Many people would say the latter group probably didn't follow the diet carefully and gradually ate more and more of the things they shouldn't eat.

But now there's some evidence that insulin resistance in the brain can predict weight-loss and weight-gain patterns. A German research group showed that people with insulin resistance in the brain lost less weight than people who were insulin sensitive and then regained the weight, whereas the insulin-sensitive ones were able to keep the weight off.

Apparently, the insulin sensitivity in the brain also determines where fat will be deposited. Those with brain insulin resistance deposited more fat in the visceral area, and this fat is supposed to be more detrimental than subcutaneous fat.

So what can we do with this information? At this time, not much. I don't know about you, but I'm not keen on injecting insulin into my brain.

However, knowing about this effect may help if you're one of the people who doesn't lose much weight even though you're following a diet strictly. When that happens, many health people probably blame you, assuming you're cheating on the diet even though you say you're not.

I know that kind of disbelief by medical people. My endo put me on an ACE inhibitor, which is usually used to lower blood pressure, because she said it would protect the kidneys, and people with diabetes are at risk of kidney disease. When other medical people see I'm on an ACE inhibitor, they ask how long I've had high blood pressure. I say I don't have high blood pressure, and they give me a patronizing look. At that point, I probably do have high blood pressure because I don't like not being believed.

Determining whether or not you have insulin resistance in the brain is not simple. The researchers used magnetoencephalography and functional MRI, techniques not available at your doctor's office.

Presumably, anything that reduces insulin resistance elsewhere in the body should also reduce it in the brain, and that would include exercising and losing weight, things we mostly likely already know we should do.

But if you're still having trouble losing weight, it could be it's not a lack of willpower. It could be insulin resistance in your brain.

Sunday, April 12, 2020

Comments

I tried to reply to a Comment yesterday, and it wouldn't post.

After trying this and that and searching the internet for help, I concluded that the problem is Firefox, which is my standard browser. With Chrome, I was able to post.

Computers can be very helpful, but they can also be very time-consuming when things don't go well. I sometimes wonder about returning to paper and pencil. No, I'll be more up to date than that. How about paper and ballpoint pen.

I still remember the time my father, a lawyer, came home with an amazing device to show us all. He had a client who was developing a special pen that wasn't yet for sale, but he had one. It was called a ballpoint. We were awed.

But I digress. I just wanted to give a heads up if anyone else is having problems posting. Try another browser.

I do moderate the Comments. If it's clear that the point of the Comment is to provide a link to someone's website, I don't approve it. So if you've sent such a Comment and it didn't appear, it's the moderation not the browser that is the cause.

Saturday, April 11, 2020

"Pumping" with Regular Insulin

When you use a pump, you fill it with fast-acting insulin like Humalog or Novolog. All day and night, the pump dispenses small amounts of the fast insulin, called basal insulin, and allows you to dispense larger amounts with meals, called bolus insulin.

Now a nonelectronic simple type of insulin pump can be used with regular insulin (R). Because the device is simpler than a regular pump and because R insulin is cheaper than newer insulins, the overall cost could be lower, especially for someone with no insurance.

The basal insulins use chemistry to modify R insulin so it forms depots in the fat that then release slowly. This device uses mechanics to release the R insulin slowly.

The device is called V-Go. It is designed for people with type 2 diabetes who still produce some insulin and thus don't need such exact amounts to be injected.

You fill a reservoir with R insulin and the device releases 20, 30, or 40 units a day as a steady infusion and can also release bolus insulin in increments of 2 units, up to 36 units a day when you press a button. The device has to be filled and placed on the body once a day and then is removed and thrown out after 24 hours. You can see detailed instructions here.

The V-Go had been approved for fast-acting insulins some time ago. But recently the device was shown to be effective with R.

The V-Go is nowhere as sophisticated as a regular pump. For example, it can release insulin at only one rate, whereas pumps can be programmed to release insulin at different rates at different times of day. And if you need less than 20 units or more than 40 a day, it wouldn't work. However, it's also much less expensive.

The device costs about $75 a month if you have no insurance. This would give you enough to use one a day. And you also have to buy insulin: 2 vials for 20 units a month and 3 vials for 30 or 40 units a month. You can get R insulin at Walmart for about $25, so the total cost would be about $125 a month for the 20 and $150 for the 30 or 40. Insurance could bring the price down.

The V-Go requires a prescription; Walmart insulin does not.

And someone with good insurance might find a regular pump at a lower out-of-pocket cost, although insurance, including Medicare, won't usually cover regular pumps for type 2 patients.

If you use only basal insulin, for example, Lantus, Levemir, or Tresiba, and inject only once a day, it might not be worth the extra trouble to set up the V-Go, but if you're doing basal/bolus multiple daily injections, it could be handy, especially if you wanted to bolus at work without hauling out a pen or syringe.

If you're on a low-carbohydrate diet, R insulin actually matches the increases in blood glucose after a meal better than the faster bolus insulins because it starts slowly and lasts longer. When you're eating protein and fat and fiber, your blood glucose also goes up slowly and but stays higher for a longer time, as the fat slows gastric emptying. When you're eating mostly carbohydrate, you get spikes in blood glucose that go up quickly and come down quickly, so the faster bolus insulins are a better match for that type of diet.

Because the insulin release from the V-Go is preset (20, 30, or 40 units for the basal and multiples of 2 for the bolus), you don't have as much flexibility as you do with a regular pump. You might need a bolus of 5 units but you could get only 4 or 6. You might need 25 units a day for the basal but you could use only 20 or 30. For a type 1 patient who produces no insulin of their own, this could be a big drawback. But type 2 patients have a bit of a buffer with their own insulin production.

One caveat: the studies I found had researchers with connections to or stock in Valeritas, Inc., the maker of the device, and some of their press releases are linked to reports on the value of their stock. This doesn't mean the studies are flawed, but it's sometimes a red flag.

Nevertheless, this is an interesting addition to the armamentarium we have to control type 2 diabetes.



Saturday, April 4, 2020

Support Groups, Good or Bad?

This article recently appeared on Eurekalert. The title, "Patients with type 2 diabetes belonging to online support groups have poorer health" makes it sound as if belonging to an online support group causes you to have poorer health, which doesn't make sense.

It also contradicts other studies like this one, titled "Joining a Support Group Improves Diabetes Treatment." The authors of this study wrote that "men and women who were enrolled in an online support program were nearly twice as likely to take their medication as prescribed and less likely to discontinue it."

So what's going on here? To try to figure it out, I read the full text of the article, "Participation of Patients With Type 2 Diabetes in Online Support Groups is Correlated to Lower Levels of Diabetes Self-Managemen."

In this study, 307 patients were recruited through an online survey. Then they were asked about their diabetes self-care management (glucose management, healthcare, dietary restrictions, and physical activity) and complications related to the disease, as well as their participation in online social groups and forums (duration, time, and intensity).

The researchers found that type 2 participants involved in online support groups had lower scores in "healthcare and self-management of diabetes." They also reported more diabetes complications.

I can think of several reasons for these results.

First, we know that correlation doesn't mean causation. A patient who follows medical advice and has wonderful control would be less apt to scour the internet looking for information about diabetes. But a patient who follows medical advice and is having problems controlling blood glucose might go online seeking more information. So the online support groups wouldn't be causing the lower scores for diabetes control, but the lower scores for diabetes control would be causing the people to join online support groups.

The authors also mention this, saying, "We cannot predict the direction of effects between using online support groups and the disease’s self-management, that is, we do not know whether the self-management complications are the cause or the consequence of such a type of online support group."

But many readers would just read the headline and conclude that participation in a support group caused the poor control.

Second, the study relied on self-reports, which may not be accurate. I might think my self-management was wonderful when it wasn't or vice versa.

Throughout the article, it's clear that the authors think patients need to have medical professionals in charge of information. For example, "it is likely that intervention or assistance is required for those patients to select and critically analyze the information they encounter in online support groups,"  "Hence, misinformation about diabetes, including its “cure”, has been found" [in the online support groups], and "information shared and consumed in online support groups may not be 100% rigorous and veracious."

It is true that online support groups can contain misinformation. But so can professional advice. The members of various groups must decide which information is credible and which is snake oil. When I was diagnosed almost 25 years ago, the professional view (with a few exceptions like Dr Richard Bernstein) was that low-carb diets are dangerous and one should follow a Food Pyramid that prescribed a lot of white bread and rice. Since then, the tide has turned, and now many, if not most, professionals are supporting low-carb diets.

But the point of this blog is not to criticize medical professionals. Rather, the point is that the headlines describing diabetes research, written by journalists trained to find interesting stories, not physicians, may be misleading.

So if you see a headline that sounds too good to be true ("Eating food X will cure your diabetes") or unlikely ("Just 30 minutes of exercise a day will make your diabetes go away"), make sure you read as much of the article as you have access to and decided if the headline is really supported by the evidence.

Monday, March 9, 2020

Coronavirus

Diabetes Daily has a blogpost on coronavirus as it relates to people with diabetes.

There's no reason to panic. But this is a good time to be extra careful with your blood glucose levels, as high levels increase the risk of various infections.

One benefit of having diabetes is that it almost forces you to eat a healthy diet. I'm sure that someone who eats a whole-foods diet for diabetes is in better shape to fight off infections than a nondiabetic who lives off fast food and boxed dinners.






Friday, March 6, 2020

More Reasons to Eat Low Carb

Several recent studies have supported the consumption of low-carbohydrate diets, especially, of course for people with diabetes but also for people without the disease.

The first study showed that although artificial sweeteners by themselves don't affect metabolism or the brain's sensing of a sweet taste, when these sweeteners are eaten along with carbs, they do, causing insulin resistance and a decrease in the brain's response to a sweet taste. These changes increase the risk of obesity.

In other words, it's OK to drink a diet soda with some steak, but not with french fries.

The mechanism of this effect is not clear, but it could explain seemingly contradictory results of studies of artificial sweeteners. Some studies may have given the sweeteners along with carbs, say adding them to yogurt, whereas others did not.

The full text of the study is available. I found it a bit confusing. For example, they say, ". . . in healthy human adults we observed reduced insulin sensitivity and blunted brain response to sucrose following consumption of seven 355 mL beverages over 2 weeks," but they don't say what the beverages contained.

Nevertheless, the overall conclusions are interesting: "consuming sucralose with, but not without, a carbohydrate rapidly impairs glucose metabolism." Of course, if you're on a low-carb diet, you're less apt to be using a sweetener with significant amounts of carbohydrate.

Another study suggests that low-carb diets may help prevent age-related changes in the brain. The authors say that communication between brain regions destabilizes with age, starting in the late 40s, and destabilization correlates with poorer cognition and accelerates with insulin resistance.

The researchers found that glucose decreases, and ketones (which are formed when glucose ingestion is low) increase, the stability of brain networks. 

The authors say that as people get older, "their brains start to lose the ability to metabolize glucose efficiently, causing neurons to slowly starve, and brain networks to destabilize." Hence a ketone-producing low-carb diet could provide the energy the brains need.

They used functional MRI to image the brains of 1000 people aged 18 to 88 and found that destabilization was associated with impaired cognition and was accelerated with type 2 diabetes, which affects the neurons' ability to metabolize glucose. They found that either a low-carb diet or a ketone-rich drink stabilized the networks.

The last study found that mice fed a ketogenic diet were better able to fight off the influenza virus than mice on high-carbohydrate diet. The authors said that the diet enhances the production of a certain type of T cell that produces mucus in the lungs that helps to trap the virus.

This study was done with the flu virus, and there is no evidence that a ketogenic diet would protect against coronavirus. But perhaps it could. We know that high blood glucose levels weaken your immune system, and people on low-carb diets tend to have lower glucose levels, so it could help in that way as well as possibly triggering lung changes.

Not everyone is happy on a low-carb diet long term, but it's certainly worth trying.


Sunday, February 23, 2020

More Misleading Headlines

A recent article in Eurekalert says in the headline, "University of Minnesota researchers discover Mediterranean diet ingredient may extend life." This illustrates two problems with popular science articles.

First, the authors emphasize the university where the research was done more than the research itself. Of course, this is the job of the PR people who write press releases, as sites like Eurekalert and Science Daily simply print the press releases as they come in, without editing them.

Second, and more important, the headline mentions "Mediterranean diet ingredient," which turns out to be olive oil. If they mean olive oil, why don't they say olive oil. People on a lot of different diets use olive oil. But seeing something in a headline tends to make people remember it. So many will see this headline and think, "Oh yes. If I follow a Mediterranean diet, I'll live longer."

That might be true if they're currently on a fast-food diet or a diet with lots of processed foods. For someone without diabetes, I think the so-called Mediterranean diet is healthy, even though it doesn't represent what many people in that part of the world actually eat. But the diet emphasizes whole grains, which make blood glucose (BG) go up in people with diabetes. Of course, whole grains are better than highly processed grains, but better doesn't mean best. And many people don't really understand what a whole grain is.

Corn and rice are whole grains, but in people with diabetes they'll make BG levels soar.

Health writers, and even some researchers, tend to get on the Diet du Jour bandwagon. You're more apt to get funding if you're researching the popular Mediterranean diet, looking at it from some new angle, than if you're researching the Blubber and Kale diet, which no one eats.

I'm all for informing nonscientists about research results. But not if the publicity is misleading. In this case, the original article was titled "Lipid Droplet-Derived Monounsaturated Fatty Acids Traffic via PLIN5 to Allosterically Activate SIRT1," and although it mentioned that the Mediterranean diet is high in monounsaturated fats (olive oil is monounsaturated), the focus of the research was on how olive oil helps, not on any life extension of that diet.

They write, "While undoubtedly a plethora of components in the Mediterranean Diet contribute to its positive effects on health, the data presented herein provide at least one feasible biological mechanism that may underlie these well-established benefits."

Almost any whole-food diet will show benefits when compared to the Standard American Diet. Maybe the mechanism of the benefits of the Mediterranean diet is simply eliminating chicken nuggets, cheeseburgers, french fries, and doughnuts rather than using more olive oil.