Thursday, December 13, 2018

Evesdropping Viruses

This has absolutely nothing to do with type 2 diabetes. At least not yet. But it's fascinating.

https://www.npr.org/sections/goatsandsoda/2018/12/13/676389858/a-virus-can-eavesdrop-on-bacterial-communication

Apparently, viruses can intercept molecules bacteria use to communicate with themselves and use that information to time their attack on the bacteria.

Are bacteria and viruses intercepting molecules human organs use to communicate? Or are various organs hijacking molecules other organs use to communicate with their kind?

It opens up a whole world of new ways of thinking about physiology.

TMAO

A recent press release reported on a link between high blood levels of a compound called TMAO (trimethylamine N-oxide) and heart disease. Then they said high TMAO levels are linked to a diet rich in red meat, and such people have TMAO levels three times as high as those who eat mostly white meat or no meat.

The authors defined "rich in red meat" as about 8 ounces of steak daily.

Horrors! Sounds as if we should all avoid red meat and try to lower TMAO levels.

But wait! Another recent press release says we should all eat more vegetables and fish because these foods increase our TMAO levels, and "low-dose treatment with TMAO reduced heart thickening (cardiac fibrosis) and markers of heart failure in an animal model of hypertension."


The authors of the second study write, "It was previously thought that TMAO blood plasma levels--and heart disease risk--rise after the consumption of red meat and eggs. However, "it seems that a fish-rich and vegetarian diet, which is beneficial or at least neutral for cardiovascular risk, is associated with a significantly higher plasma TMAO than red meat- and egg-rich diets, which are considered to increase the cardiovascular risk."


Is it any wonder that people are confused about which diet is best to follow in order to reduce the risk of heart disease?

The effects of diets are complex. For one thing, different people may react differently to the same thing, and rodents may also react in a different way. For another, it's not usually just one component of a diet that is important; it's the diet as a whole. A red-meat and chocolate cake diet is different from a red-meat, vegetable, and salad diet. A 16-ounce steak has a different effect from 4 ounces of steak.

And TMAO could have a U-shaped effect so that small increases were beneficial but large increases were not, or vice versa.

Rat experiments don't always translate into effects on humans, but they're suggestive. Also, the second study was done in an animal model of hypertension.

Today, certain memes are popular, including "eat more fruits and vegetables" and "avoid red meat." But most fruits raise blood glucose levels in people with diabetes, and also to some degree in those without the disease. Sometimes it seems as if research is designed to prove these memes rather than to learn something new. It's easier to get research grant money if you are supporting the current dogma. Not long ago, that was low-fat, and people who didn't support that concept had trouble getting research grants. The South African scientist Tim Noakes, was accused of "unprofessional conduct" for advising a mother to wean her infant onto a low-carbohydrate diet. He was eventually found not guilty of any wrongdoing.

So we don't yet know if TMAO is beneficial or detrimental. As most research papers say, "More research is needed."


Wednesday, December 12, 2018

Offering Hope

Charles Mattocks is passionate about diabetes. Controlling diabetes, that is.

He understands that because it's difficult to live with diabetes, some people just give up and don't try to help themselves.

Mattocks understands how difficult it is to live with diabetes because this celebrity chef, author, and TV producer has type 2 diabetes himself. He was diagnosed in 2011 at the age of 38 and was determined not to let the diabetes ruin his life. At first he controlled with diet and exersise, but then when his dietary vigilance relaxed a bit too much, he went on medication. A year after getting back on the wagon, he was able to come off the medication.

"Diabetes could kill me, but being diagnosed has saved my life and put my health at the forefront," he said." But Mattocks is concerned with more than just his own health. He wants to help other people deal with their diabetes, and especially to help people not yet diagnosed with diabetes avoid ever getting that diagnosis.

He realizes that most people don't know much about diabetes and feels that if he'd known when he was a kid what he knows now about diabetes, he never would have gotten it. For that reason, he's written a children's book titled "Diabetes and Healthy Eating." He's also involved with an RVcalled "Diabetic You RV" that travels around the country and offers information and free blood glucose and foot checks for anyone interested. In addition to calling attention to diabetes with its colorful decorations, the RV is staffed with medical people who can offer help to those interested.

Currently being worked on, the RV should be back on the road in a few months.

But Mattocks' primary focus is a TV reality show that takes a small number of people with diabetes to a resort in Jamaica, where he was born, and has various diabetes experts work with them for a week. His goal is to give hope to people who are struggling, and to give the viewers of the reality show hope as well. He feels that showing real people, not actors, with type 2 struggling but eventually succeeding in taking control will inspire others to do the same.

Some episodes from the first season, produced in 2017, can be seen here. He is currently working on a second season.

Mattocks has done many things in his life so far. He's traveled around the world to see how diabetes is affecting people in other nations. India is especially hard hit. He's also been involved with cooking and had a TV show called "The Poor Chef." Before his diagnosis he published a cookbook called Eat Cheap, but Eat Well, and in 2014 the American Diabetes Association published his The Budget-Friendly Fresh and Local Diabetes Cookbook.

Like Mattocks, because I know how very inconvenient, not to mention expensive, it is to have type 2 diabetes, I would also like to do what I can to prevent others from following in my path. But it's difficult. Most people simply aren't interested. When I suggested to a sister that she test members of her family once a year so that if they had the genetic predisposition, the disease would be caught early, when it's easier to control.

Her answer: "Why worry about a disease you may never get?"

If someone in a family in which the disease has occurred several times isn't interested, what is the likelihood that the average person would be? Most people assume it will never happen to them, even when it runs in the family and even when they're overweight. So I got discouraged at trying to help people prevent the disease and have focused instead on reading about research and trying to communicate the most interesting research results through this blog.

Hence it's good that people like Mattocks, who has a lot of energy and the ability to communicate well through talks and TV shows, are still in there fighting for people who might not be able to fight on their own.

There's a vast difference in how people with type 2 diabetes are learning. At one end of the spectrum are people who get all kinds of expensive gadgets like continuous glucose monitors and fancy software, document everything they eat in a nutrition program, join online Facebook groups and exchange information with others with the same interests. At the other end are the people who get a diagnosis, get medications, and expect the medications to control their disease while they continue to eat the same unhealthy food they've always eaten and continue to avoid exercise whenever possible. Sometimes, because of the cost, they don't even take the medications. Then they get complications like having a leg amputated or losing most of their sight. Of course, most people are somewhere in the middle of these extremes, but sadly, I think most patients are closer to the latter group than to the former.

Perhaps a reality show on TV will reach some of these people. I do hope so.

Anyone wishing to learn more about Mattocks and his show can go here.




 

Tuesday, November 6, 2018

Protein and Kidneys

When I was diagnosed with type 2 diabetes in 1996, a nurse handed me the American Diabetes Association 1500-calorie diet, which said I should eat 179 grams of carbohydrate a day. That made no sense to me. So when I saw my doctor, I asked, "If diabetes is a disease in which you can't deal with carbohydrates, why did the nurse tell me to eat all this starch?"

The doctor looked surprised at the question and then thought and answered, "Well, protein damages kidneys, and as a diabetic, you're at increased risk of kidney damage. Fat causes heart disease, and as a diabetic, you're at increased risk of heart disease. The only thing left is carbohydrate."

Many of us have questioned the assumption that protein damages healthy kidneys, so it's nice to see some research supporting that idea. True, this study is a meta-analysis, in which researchers do statistical analyses of previously published research, and meta-analyses can have problems. For instance, the populations studied by each group may not be very similar. The end points may vary. Nevertheless, such studies give suggestions about the issue at hand.

This study says nothing about protein consumption by people who already have damaged kidneys. In such cases, some people think plant proteins are better than animal proteins.

My doctor's statement about fat causing heart disease has also mostly been disproven, but I won't get into that here.

Monday, November 5, 2018

Weight and Nuts

Sometimes people do research and then write it up in a way that reveals that they had preconceived notions about the results. An example of this is a recent report suggesting that eating nuts may help you to lose weight. The report was presented at the American Heart Association's November meeting.

OK, that makes sense. Most nuts contain a lot of fat, and fat slows down gastric emptying, so you feel full longer.

The study involved a food-frequency questionnaire, which can be fairly inaccurate. Who remembers everything they ate last week, or even yesterday? But that's not the problem I'm concerned with.

The researchers said the nuts were eaten "in place of foods generally considered low in nutritional value." So it's not just eating nuts but eating nuts in place of junky foods. One assumes they mean empty calories in sugary drinks or starchy highly processed foods.

But wait! They said "Substituting one serving a day of any type of nuts in place of one serving of red meat, processed meat, French fries, desserts or potato chips was associated with less weight gain over the four-year intervals."

Red meat is low in nutritional value? Since when?

According to P. G. Williams at the University of Wollongong, Australia,

"Lean red meats are:

"• An excellent source of high biological value protein, vitamin B12, niacin, vitamin B6, iron, zinc and phosphorus 
"• A source of long-chain omega-3 polyunsaturated fats, riboflavin, pantothenic acid, selenium and possibly also vitamin D
"• Mostly low in fat and sodium [this analysis refers to meat with fat trimmed]
"• Sources of a range of endogenous antioxidants and other bioactive substances including taurine, carnitine, carnosine, ubiquinone, glutathione and creatine."


This study was done in the lab of Walter Willett, who has long opposed eating red meat, and I suspect that because the researchers consider red meat to be unhealthy, they just lumped it in with foods considered low in nutritional value. This is not good science.

Even perfectly done nutritional studies can be confusing because so many factors are involved. Eating more of X usually means eating less of Y, so if the results are different, which was the crucial factor? Most people, including professional dieticians, make errors when reporting what they ate. And of course there are interactions between foods. Maybe food A has one effect when eaten with Food B but not when eaten with food C. And so forth.

So to see a misleading statement like the above in a report from Harvard is discouraging.

Will we ever know what the healthiest diet is? Probably not, because what works for one person may not work for another. What makes blood glucose go up for one person may not for another. And a diet that person A can stick to for years might be different from a diet person B could tolerate long term.

Our best approach is to try different diets and see how they affect our daily blood glucose levels and less frequent lab results and then choose one that works for us.

And it's probably also a good idea to try to ignore popular press articles about diet, which are often slanted to favor some marketing group. The nut study was funded in part by the California Walnut Commission.


Thursday, October 25, 2018

Glucose in Tears

About 20 years ago, shortly after I was diagnosed with type 2 diabetes, I read an article that described measuring blood glucose (BG) levels in tears. I thought that was wonderful, as it would avoid what popular press articles like to call "painful finger pricks" but which are actually not-very-painful but annoying tests one has to do multiple times a day if one wants good control.

So I mentioned the article to an endocrinologist who was in charge of a clinical study I was in. She laughed and said so many novel ways of measuring BG had been proposed, but none of them had ever made it to the market. "I'll be interested when it becomes commercially available," she said.

Well now, 20 years later, a company based in The Netherlands has proposed measuring BG levels in tears. This version involves putting a tiny sensor under the lower eyelid. The sensor measures BG levels continuously and broadcasts them to a smartphone.

The company has published the results of studies in six patients and says the device is accurate, with no adverse events reported. They are planning a study in 24 people with type 1 diabetes.

Well, it does sound nice, but I'll be interested when it becomes commercially available.

Friday, October 19, 2018

Beta Cell Rest

For many years, some people have been saying that if you can rest your beta cells by decreasing their workload, they can recover some function.

Richard Bernstein, the author of Dr Bernstein's Diabetes Solution, who promotes low-carbohydrate diets for people with diabetes, is one of them. He cites experiments with the Biostator, developed in the 1970s, a machine that kept blood glucose (BG) levels close to normal levels. After only 2 weeks on the machine, he said some people had normal BG levels for up to 2 years, despite eating a standard American diet. [I can't locate a reference for this study.]

The Biostator is large and bulky, and the patients had to be admitted to a research lab for the study, so it's not yet a practical solution, although so-called closed-loop insulin pumps are being developed. But it illustrates the concept. Keeping BG levels normal is good for your beta cells.

A similar effect is often seen in type 1 patients who have a "honeymoon period" shortly after they are started on insulin. However, that effect doesn't last.

There hasn't been much experimental evidence on this topic, although there is some, see here and here. So it was nice to see a recent study that supports the concept. Although, like so many studies, it was done in mice, the results are interesting.

The authors say that improving glucose levels with various diabetes drugs not only increased the insulin content of the beta cells, but restored normal biphasic insulin secretion.

Normally, beta cell secretion of insulin occurs in two phases. After eating carbohydrate, the first phase is very rapid, and it doesn't last long. But it keeps BG from going very high, in part by stopping the liver from releasing glucose. The second phase occurs later and persists until no more carbohydrate is coming into the intestine, and it is able to keep the BG down for a long time.

People with type 2 diabetes almost always lose the first-phase insulin response. This means the BG goes very high after a carbohydrate load, and because it's so high, if they're still able to secrete insulin, the beta cells secrete a lot of it. This is often so much that the person later goes low. In fact, going low about 4 hours after a carbohydrate-rich meal is one of the warning signs of future diabetes. I had this about 5 or 10 years before I was diagnosed with type 2.

So the fact that the first-phase insulin response was restored is promising. I also learned that my first-phase insulin response was restored to about 70% of normal when I was in a study of high-dose aspirin at Joslin. I assume I lost it again when the study was over, although I had no way of testing that.

These authors conclude, "Thus, this study provides evidence that alleviation of metabolic demand on the beta cell, rather than targeting the beta cell itself, could be effective to delay the progression of T2D."

And how can people alleviate the metabolic demand on the beta cell? By eating less carbohydrate, of course. In fact, the "normal" BG levels reported for the Biostator  are not as good as those reported by type 1 patients on the Type1Grit Facebook page. (If you're not on Facebook, you can see results here.) The Biostator was set for BG levels of 90, but they actually fluctuated a lot.

 Low-carb diets have been anathema among some diabetes organizations like the American Diabetes Association, but they are slowly gaining acceptance even by these groups.

Another way to reduce the load on the beta cell is to inject insulin. The standard treatment of type 2 used to be to tell people to lose weight and exercise and come back in three months. Now some say it's better to start right out on insulin. This will reduce the workload on your beta cells and let them recover somewhat at a time when you still probably have a lot of them. Here is an example of that. Then when they have recovered a bit, you can phase out the insulin.

Waiting for three months, especially if given a high-carb low-fat diet, will just burn out more of these precious cells. And most overweight patients have been trying unsuccessively to lose weight for decades, so telling them to lose weight isn't very helpful.

One problem is that some people don't like needles, and they see using insulin as a sign of failure. It's not. It's taking charge of your health. And if you use it from the get-go so your beta cells recover and you then stick to a sensible diet, you may be able to go off all drugs in the future.

Rest your beta cells, and your beta cells will thank  you.



Saturday, September 1, 2018

Sucralose revisited

Does sucralose (Splenda) have effects that were not reported when it was approved by the FDA in 1998? This research suggests that it does. A summary can be found here.

The developers originally claimed that most of the sucralose was not absorbed from the intestine but was secreted unchanged in the feces. And they said the small amount that was absorbed was secreted unchanged in the urine.

But this research shows that, at least in rats, some of the sucralose is metabolized to produce two new products that haven't been described before. They also show that some of the sucralose accumulates in fatty tissue.

The researcher say that the reason their findings differ from those used to gain FDA approval because they used more sensitive methods.

No one knows what the effect of having sucralose or its metabolites in fatty tissue is, so the researchers suggest that sucralose should be reexamined by the FDA. This is a long process, so in the meantime what should consumers do?

One commenter said that the amount of sucralose given to the rats is the equivalent of a 150-lb person drinking about 90 Diet Cokes in one day, suggesting that this research is irrelevant to real life. However accumulating a tiny amount in the fat tissue every day could build up over time in a person consuming a lot of sucralose.

Sucralose seems to be passed into breast milk, and because growing infants are more susceptible than adults to the effects of any toxins, it would be prudent to find alternative sweeteners during pregnancy and nursing.

Today, as I pointed out recently, we have a choice of many sweeteners. We really don't know the long-term effects of consuming a lot of any of them, even those extracted from the stevia plant. So one approach would be to give up sweet things altogether. Most people wouldn't want to do that.

Another approach would be to eat small amounts of different sweeteners, rather than choosing only one. And downing huge amounts of diet sodas is not a great idea regardless of how they are sweetened.

We should remember that this is only one study, done in rats, and it needs to be replicated before the results are certain. In the meantime, we should be aware of the possible detrimental results from yet-another sweetener.

Friday, August 31, 2018

Are low-carb diets dangerous?

The popular press is having a field day with this studywith headlines like "Is your low-carb diet killing you?"

Well, my exhaustive analysis is as follows:

HOGWASH!

If you want more details, Zoe Harcomb has done a thorough review.
 

Tuesday, August 28, 2018

Sugars


When I was diagnosed with type 2 diabetes in 1996, the number of artificial sweeteners was limited. There was saccharin, of course, which had been discovered in 1878 and offered for sale in the 1880s. But studies in rodents showed that it could cause bladder cancer when used in huge amounts, so some people were wary of it.

Cyclamate, aspartame, and sucralose became popular in the 1960s and 1970s. Then it was discovered that huge amounts of cyclamate produced bladder cancer in rodents, and in 1970 it was banned in the United States. It is still sold in Canada. Both aspartame and sucralose are still on the market in the United States.

Aspartame was controversial, with internet groups claiming all sorts of horrid side effects, although the FDA said it was safe. In 2002 a related sweetener, neotame, was approved.

Another sweetener, acesulfame K, had a slightly bitter taste and was primarily used mixed with other sweeteners.

Today there are a myriad of artificial sweeteners. Stevia, which comes from a South American plant, has been used there for more than 1500 years. One can use the whole leaves, and one summer summer I grew stevia and used some of the leaves, but some people complain of a licorice flavor. The whole or ground leaves have not been certified by the FDA as GRAS (generally recognized as safe) for food products, although they approved it as a supplement..

However, companies have also isolated the sweet compounds from the stevia leaf, mostly one called rebA, or rebaudioside A. These purified compounds have been FDA approved for use in food. RebA can have a bitter taste if one uses too much.

All of these sweeteners are vastly sweeter than table sugar, or sucrose. For example, saccharin is 200 times sweeter, and neotame is more than 7000 times sweeter than sucrose. This means one has to use tiny amount, difficult to measure. And for this reason many companies cut the sweetness of the compounds with substances like maltodextrin. Some even use glucose. When one is on a low-carb diet, the addition of these bulking agents is problematic.

Another problem with these compounds is that because you need so little of them, they won't reduce the freezing point of frozen desserts as sucrose does. So if you try to make ice cream with saccharin or stevia, it will become rock hard when you put it in the freezer. Fran McCullough in her excellent book The Low Carb Cookbook, published in 1997, has several pages devoted too making ice cream that won't turn into icebergs. None of the suggestions like using alcohol or gelatin worked for me,

But today we have more options, with granular sweeteners that are measured just like table sugar. A popular combination is erythritol combined with a sweeter compound.

Erythritol is a sugar alcohol, but unlike sorbitol and similar sugar alcohols, it doesn't cause gas. This is because it is absorbed into the bloodstream and excreted in the urine rather than going down the intestinal tract to be fermented in the colon to produce gas. It's not quite as sweet as sucrose, so most products combine it with one of the supersweet substance mentioned above.

One popular granular sweetener is Truvia, which consists of erythritol and stevia. Another one combines erythritol and lo han guo, which comes from a southeast Asian plant. Like RebA, the extract has been clasified GRAS. A third, Swerve, combines erythritol and "oligosaccharides." They all seem to contain "natural flavorings," without saying what they are.

All three of these products are now available at my local supermarket.

Two new granular sugars have also come on the market. These are allulose and tagatose. Both are isomers of fructose. An isomer is a compound with the same chemical formula but with a slightly different arrangement of atoms so the enzymes that process them may not recognize them.

Allulose is now available at my supermarket, but you can also get it and tagatose online. These product are not cheap. A pound of sucrose costs about 50 cents. A pound of allulose is about $12.

Despite the price, I decided to try the allulose and tagatose. First I tested the effect on BG, using tiny amounts (1 teaspoon) so I wouldn't spike too high with the control (sucrose). Just 1 teaspoon of sucrose made me go up 20 points on an empty stomach first thing in the morning, and I was back to 80 in an hour. One teaspoon of tagatose made me go up 6 points, as did allulose. As my BG usually goes up after I get up even if I don't eat, it's not clear if this is meter variation, effect of getting up, or the allulose/tagatose, but it doesn't look as if these sugars have a big effect. I don't want to test larger amounts.

I didn't test Truvia or Swerve.

Then I made some ice cream. Eureka! The ice cream was delicious and didn't get rock hard in the freezer. Then I made some crustless cheesecake. Same thing. At last, despite the price, we can occasionally have a traditional dessert with very little effect on blood glucose levels.

Today liquid sweeteners are also more easily available. I didn't use to buy sucralose at the grocery store because of the carby bulking agents it contained. A liquid version was available online, but not at my grocery store. Now the local grocery store carries both liquid sucralose (Splenda Zero) and a stevia version (also Splenda Zero but in a green bottle). Sweet Leaf has offered liquid stevia for some time. Of course the liquids contain preservatives, so if you're sensitive to those, this wouldn't be an answer.

Who knows what new products will emerge in the future or what horrendous side effects will be attributed to the existing sweeteners. Ideally, it would be good to not eat anything sweet so one would lose the taste for sugars. But this isn't an ideal world, and I do like whole-milk yogurt with some flavoring and some sweetener. At least we now have more choice.

Odd Logic about Milk

A study presented at ESC Congress 2018 in Munich has concluded that current dietary guidelines are wrong. With the exception of milk, they said there's no relation between dairy consumption and heart disease, and in fact dairy protects against both total mortality and mortality from cerebrovascular causes.

But what is really odd is the final sentence of the press release (the results of the meta-analysis haven't been published yet).

"And given the evidence that milk increases the risk of CHD, it is advisable to drink fat-free or low-fat milk." Huh? A complex food increases the risk of CHD and the authors assume it's the fat in the milk that is causing the problem?

This is an example of researchers having a preconceived notion and then interpreting their results accordingly. They're assuming fat is bad, and thus if milk has deleterious results, it must be because of the fat. This is despite the fact that cheese, which has more fat and less lactose than milk, is protective.

It's faulty logic like this, as well as reliance on inaccurate Food Frequency Questionnaires,  that has made me ignore most nutritional studies.




Monday, August 6, 2018

Self-Monitoring Saves Money in Finland

"Physicians continue to recommend routine self-monitoring of blood glucose for patients with non-insulin treated type 2 diabetes, in spite of its lack of effectiveness (italics added), because they believe it drives the lifestyle changes needed to improve glycemic control." This is from a recent press release from the American Academy of Family Physicians.

This suggests that the "lack of effectiveness" is a fact, not their opinion, despite the fact that they go on to say that there are both proponents and opponents of self-monitoring of blood glucose (SMBG).

I've discussed this before here  and here. Basically, SMBG does little good if patients are given a meter and told to test once a day, usually fasting or if they're told to test more often, usually before meals but not after eating but they're not told what to do with the results.

 Motivated patients have used their meters to determine which foods make their blood glucose (BG) levels increase the most, and they then eliminate these foods or greatly reduce their consumption. When they do, they find great improvement in their measures of control such as the hemoglobin A1c test. However, such success stories are annecdotal, not formal studies.

One common criticism of SMBG is the cost. Thus it is encouraging to see a Finnish study showing that SMBG along with an electronic feedback system reduced total costs by almost 60%. The study was done in a rural area, and the researchers said that reducing travel costs contributed about 20% to the total savings. So the combination of SMBG and electronic feedback reduced total costs about 40%.

The travel costs are the focus of this article, so there's no discusion of the SMBG or the electronic feedback. Nevertheless, it's encouraging to see that some health care systems recognize the importance of SMBG in treating people with type 2 diabetes.

Thursday, July 26, 2018

Nondiabetic blood glucose levels

The internet is buzzing with articles saying that nondiabetics can have high blood glucose (BG) levels after meals but they don't know it. Big news. Most people with diabetes already know that, because most have tested "nondiabetic" friends and relations and have seen some readings that are higher than is considered normal.

I found that some friends would go up to over 160 mg/dL after meals. But unlike most people with diabetes, they'd then return to baseline in a couple of hours. I confess I didn't do exhaustive testing because most people I know don't especially like to have their fingers pricked.

One friend seemed to get diabetes complications without having been diagnosed; for example he had frozen shoulder and trigger finger, both more common in people with diabetes. So I tested him. His fasting number was 71. An hour after a breakfast of white bread, jam, and honey,  his BG was 101, hardly a diabetic number. As it took him about 5 minutes to get up the courage to prick his finger, I didn't do more testing.

But of course all this is annecdotal. Some researchers have also tested people who are considered nondiabetic. Some time ago (2006) a Swedish researcher named Christiansen hooked a bunch of people up with continuous glucose monitors (CGMs) and looked at what their BG levels did over the course of a day. After a high-carbohydrate breakfast, the BG levels of some of them went quite high, although the average was only about 120. There was a lot of variation, some people's BG  hardly budging and others going high. I hope you can see this here (click on thumbnails). The one that looks like tangled shoelaces shows the individual variation. I can't get the lecture to play anymore, or get the URL of single slides.

Here's a German study of nondiabetics.

But the recent research that is causing so much comment was done by Michael Snyder's group at Stanford. Snyder is the geneticist who had his own DNA studied and in the process discovered that an infection had triggered a sharp rise in his BG levels, leading to a diagnosis of type 2 diabetes. Because he was diagnosed at such an early stage, he was able to reverse the condition with diet and exercise, although it took six months for his BG levels to return to normal.

This new research hooked people, mostly nondiabetic according to standard tests, up to CGMs and studied what happened with their BG levels for 2.5 hours in their normal environment. They found that people tended to fall into three clusters, which they named glucotypes. Some had relatively flat curves, which they called L, some had "severe" curves (S), and some had in-between or moderate ones (M), as shown here.









 From Hall et al., PLOS Biology  https://doi.org/10.1371/journal.pbio.2005143  

They said that recent evidence suggests that glucose variability, more than fasting BG or hemoglobin A1c, predicts the development of cardiovascular disease. And they found that more than 25% of the "normoglycemic" individuals were in the S category.

 Then they studied how a smaller group of people would react to standard meals: cornflakes and milk, a peanut butter sandwich, or a PROBAR protein bar (an odd choice in my opinion; why not use real food?). Oddly, the "protein bar" had less protein than the other meals. They discovered what most people with diabetes already know: a breakfast of cereal and milk will make your BG soar. In this study that happened even with many of the people who were not supposed to be diabetic. Christiansen showed the same thing.

This study produced a lot of data. How much can be used in the real world is unclear. For example, they suggest that using CGMs in people before they're diagnosed with full-blown diabetes would help identify those at the highest risk, so they could make changes before it was too late. This is true. But insurance often won't pay for CGMs even for people with diabetes. Are they apt to pay for them in people without a diagnosis? Maybe some day, but probably not now.

And how many people warned that they were on the path to diabetes would actually do something about it? We all know that overeating tends to make people put on weight. But when offered the choice of cheesecake or an apple, how many people choose the apple?

The data do show clearly how different people vary in their insulin resistance and BG control. An earlier study showed how different people vary in their BG responses to different carbohydrate foods, sometimes showing opposite responses to rice vs bread, for example.

Insulin release is biphasic, and most people with type 2 diabetes lack the rapid phase 1 response that knocks down the BG before it gets too high, but they still have the phase 2 response that kicks in later and lasts as long as the food is being digested. This study did not differentiate (which would not be easy to do).

If you want to slog through the full text, it's available. But I warn you, it's slow going. There is lots of complex statistics, much of the supporting information is in supplementary material, and the figure legends are sometimes on different pages from the relevant text, so you have to go back and forth. But I suppose going from page to page is a lot easier than doing this exhaustive research, so I shouldn't whine.

One interesting sentence in the article is ". . .  American Diabetes Association dietary recommendations are based mainly on reduction of carbohydrate content." When I was diagnosed in 1996 we were told to increase our intake of carbohydrates, and a standard ADA breakfast if you were hospitalized was orange juice, toast and jam, cereal, and skim milk. A friend was told to add raisins to her oatmeal "to get the carb count up." Luckily, I never listened to the ADA and went on a low-carb diet about 6 months after diagnosis.

The essence of this research is that type 2 diabetes is complex, there are different manifestations of the disease, and it would be nice if we could all have the tools to decipher them. Someday we will, but likely not in the near future.