Tag Archives: type 2 diabetes

Metformin: More Effective in Blacks Than Whites

Diabetes Self-Management has some of the details.

The implication is that the genetically determined physiology of black diabetics is different from whites. There could be other explanations, admittedly.

 

Here’s why I bring this to your attention. You don’t see me review many scientific articles involving mice, rats, pigs, or rabbits. In fact, I hardly ever read them. I take care of human patients. I suspect there are too many genetic differences between us and them that clinically pertinent studies are rare.

If you read my blogs carefully, you’ll also note I often hesitate to generalize clinical study results from one ethnic group to others. The different black/white responses to metformin validates my approach.

Type 2 diabetes in whites and blacks may not be the same disease, and it could be different in Asians, Australian aborigines, and North American Native Americans. For that matter, Ethiopian black diabetes may not be the South Africa black diabetes.

You may also be starting to understand why there’s so much confusion about which diabetic drugs are the best. We have 12 different classes of drugs now; what’s best for me may not be best for you.

Steve Parker, M.D.

PS: Type 1 diabetes, on the other hand, is probably more homogenous across ethnic and national boundaries.

Dr. Richard Feinman Doubts Red Meat Causes T2 Diabetes

This looks healthful to me, despite the red meat

This looks healthful to me, despite the red meat

At least one recent study implicated red meat consumption as a cause of type 2 diabetes. Dr. Richard Feinman at his blog takes a close look at the 2013 study and points out the great difficulty in making the leap from red meat to diabetes. I think Dr. Feinman’s point is best made by his graph about half way through the post, showing steadily decreasing red meat consumption as T2 diabetes takes off over the last four decades. (I assume all the figures are based on U.S. data.)

For the opposing viewpoint, read the original study (linked at Dr. F’s blog) or search at Fanatic Cook.

Do I worry that red meat causes diabetes? Not much. I await definitive research.

Steve Parker, M.D.

Type 2 Diabetics Better Exercise as They Age

Steve Parker MD

Strength training (aka resistance training) is the way to build muscle mass and strength. Jogging’s more for cardiovascular endurance.

Compared to others, elderly type 2 diabetics are more afflicted with diminished leg muscle mass, leg strength, and functional capacity. Click for details.

The right exercise program can counteract these problems, improve quality of life, and prevent falls.

Steve Parker, M.D.

h/t Bill Lagakos

Eat Nuts to Reduce Cardiovascular Risk and Improve Type 2 Diabetic Blood Sugars

Paleobetic diet

Macadamia nuts on the tree

Most of the diets I recommend to my patients include nuts because they’re so often linked to improved cardiovascular health in scientific studies. Walnuts are associated with reduced risk of type 2 diabetes in women, and established type 2 diabetics see improved blood sugar control and lower cholesterols when adding nuts to their diets.

paleobetic diet, diabetic diet, low-carb diet

Apples, pecans, and blueberries: So simple even a redneck can make it (I are a redneck)

Nut consumption lowers total and LDL cholesterol levels, and if triglycerides are elevated, nuts lower them, too. Those changes would tend to reduce heart disease.

Conner Middelmann-Whitney has a good nutty article at Psychology Today.

Steve Parker, M.D.

Reference: Joan Sabaté, MD, DrPH; Keiji Oda, MA, MPH; Emilio Ros, MD, PhD. Nut Consumption and Blood Lipid Levels: A Pooled Analysis of 25 Intervention Trials. Archives of Internal Medicine, 2010, Vol. 170 No. 9, pp 821-827. Abstract:

Background  Epidemiological studies have consistently associated nut consumption with reduced risk for coronary heart disease. Subsequently, many dietary intervention trials investigated the effects of nut consumption on blood lipid levels. The objectives of this study were to estimate the effects of nut consumption on blood lipid levels and to examine whether different factors modify the effects.

Methods:  We pooled individual primary data from 25 nut consumption trials conducted in 7 countries among 583 men and women with normolipidemia and hypercholesterolemia who were not taking lipid-lowering medications. In a pooled analysis, we used mixed linear models to assess the effects of nut consumption and the potential interactions.

Results:  With a mean daily consumption of 67 g of nuts [about 2 ounces or 2 palms-ful], the following estimated mean reductions were achieved: total cholesterol concentration (10.9 mg/dL [5.1% change]), low-density lipoprotein cholesterol concentration (LDL-C) (10.2 mg/dL [7.4% change]), ratio of LDL-C to high-density lipoprotein cholesterol concentration (HDL-C) (0.22 [8.3% change]), and ratio of total cholesterol concentration to HDL-C (0.24 [5.6% change]) (P < .001 for all) (to convert all cholesterol concentrations to millimoles per liter, multiply by 0.0259). Triglyceride levels were reduced by 20.6 mg/dL (10.2%) in subjects with blood triglyceride levels of at least 150 mg/dL (P < .05) but not in those with lower levels (to convert triglyceride level to millimoles per liter, multiply by 0.0113). The effects of nut consumption were dose related, and different types of nuts had similar effects on blood lipid levels. The effects of nut consumption were significantly modified by LDL-C, body mass index, and diet type: the lipid-lowering effects of nut consumption were greatest among subjects with high baseline LDL-C and with low body mass index and among those consuming Western diets.

Conclusion:  Nut consumption improves blood lipid levels in a dose-related manner, particularly among subjects with higher LDL-C or with lower BMI.

Just What You Always Wanted: A Second SGLT2 Inhibitor (dapagliflozin or Farxiga)

Open wide!

Open wide!

Where do they get these names?!

The trade name in the U.S. is Farxiga. (How do you pronounce that?) In Europe and Australia they call it Forxiga. Go figure.

MedPageToday has the details. Here’s the FDA press release, which misspells dapagliflozin. Here’s the Australian package insert for full prescribing information. Here’s my summary of both drugs in the class at one of my other blogs.

We how have 12 classes of drugs for treating diabetes.

If you’re eating the typical high-carb diabetic diet—200 or 300 grams of carbohydrate daily—you quite likely can reduce your drug requirement by cutting back on the carbs.

Steve Parker, M.D.

 

Low-Carb Diet Works in Japanese With Type 2 Diabetes

Mt. Fuji in Japan

Mt. Fuji in Japan

I don’t know much about Japanese T2 diabetes. I’ve never studied it. Their underlying physiology may or may not be the same as in North American white diabetics, with whom I am much more familiar. Physiologic differences are suggested by the fact that Japanese develop type 2 diabetes at lower BMIs (body mass index) than do Western caucasians.

For what it’s worth, a small study recently found improvement of blood sugar control and triglycerides in those on a carbohydrate restricted diet versus a standard calorie-restricted diet.

Only 24 patients were involved. Half were assigned to eat low-carb without calorie restriction; the other half ate the control diet. The carbohydrate-restricted group aimed for 70-130 grams of carb daily, while eating more fat and protein than the control group. The calorie-restricted guys were taught how to get 50-60% of calories from carbohydrate and keep fat under 25% of calories. At the end of the six-month study, the low-carbers were averaging 125 g of carb daily, compare to 200 g for the other group. By six months, both groups were eating about the same amount of calories.

Average age was 63. Body mass index was 24.5 in the low-carb group and 27 in the controls. All were taking one or more diabetes drugs.

The calorie-restricted group didn’t change their hemoglobin A1c (a standard measure of glucose control) from 7.7%. The low-carb group dropped their hemoglobin A1c from 7.6 to 7.0% (statistically significant). The low-carb group also cut their triglycerides by 40%. Average weights didn’t change in either group.

Bottom Line

This small study suggests that mild to moderate carbohydrate restriction helps control diabetes in Japanese with type 2 diabetes. The improvement in hemoglobin A1c is equivalent to that seen with initiation of many diabetes drugs. I think further improvements in multiple measures would have been seen if carbohydrates had been restricted even further.

Steve Parker, M.D.

Link to reference.

h/t Dr Michael Eades

Which T2 Diabetes Drugs Are Popular in the U.S.?

Better living through chemistry

You may be able to avoid some of these through diet and exercise

Diabetes Care recently published results of a survey covering 1997 to 2012. The focus was on T2 diabetics age 35 or older:

“Between 1997 and 2012 biguanide [metformin] use increased, from 23% … to 53% … of treatment visits. Glitazone use grew from 6% in 1997 to 41% of all visits in 2005, but declined to 16% by 2012. Since 2005, DPP-4 inhibitor [e.g., Januvia] use increased steadily, representing 21% of treatment visits by 2012. GLP-1 agonists [e.g., Byetta] accounted for 4% of treatment visits in 2012. Visits where two or more drug compounds were used increased nearly 40% from 1997 to 2012. Between 2008 and 2012, drug expenditures increased 61%, driven primarily by use of insulin glargine [e.g., Lantus] and DPP-4 inhibitors.”

We have 12 classes of drugs for the treatment of T2 diabetes now. It’s not entirely clear which ones are the best. Since the long-term side effects of many drugs are unknown, if I had T2 diabetes I’d try to limit my need for drugs by restricting my carbohydrate consumption, maintaining a reasonable weigh, and exercising. And, no, they don’t always work.

Steve Parker, M.D.

Dr. Roy Taylor on the Cause of Type 2 Diabetes and What To Do About It

diabetic diet, low-carb Mediterranean Diet, low-carb, Conquer Diabetes and Prediabetes

Warning: this is a sciencey post

According to Roy Taylor, M.D., “type 2 diabetes is a potentially reversible metabolic state precipitated by the single cause of chronic excess intraorgan fat.” The organs accumulating fat are the pancreas and liver. He is certain “…that the disease process can be halted with restoration of normal carbohydrate and fat metabolism.” I read Taylor’s article published last year in Diabetes Care.

(Do you remember that report in 2011 touting cure of T2 diabetes with a very low calorie diet? Taylor was the leader. The study involved only 11 patients, eating 600 calories a day for eight weeks.)

Dr. Taylor says that severe calorie restriction is similar to the effect of bariatric surgery in curing or controlling diabetes. Within a week of either intervention, liver fat content is greatly reduced, liver insulin sensitivity returns, and fasting blood sugar levels can return to normal. During the first eight weeks after intervention, pancreatic fat content falls, with associated steadily increasing rates of insulin secretion by the pancreas beta cells.

bariatric surgery, Steve Parker MD

Band Gastric Bypass Surgery (not the only type of gastric bypass): very successful at “curing” T2 diabetes if you survive the operation

Taylor’s ideas, by the way, dovetail with Roger Unger’s 2008 lipocentric theory of diabetes. Click for more ideas on the cause of T2 diabetes.

Here are some scattered points from Taylors article. He backs up most of them with references:

  • In T2 diabetes, improvement in fasting blood sugar reflects improved liver insulin sensitivity more than muscle insulin sensitivity.
  • The more fat accumulation in the liver, the less it is sensitive to insulin. If a T2 is treated with insulin, the required insulin dose is positively linked to how much fat is in the liver.
  • In a T2 who starts insulin injections, liver fat stores tend to decrease. That’s because of suppression of the body’s own insulin delivery from the pancreas to the liver via the portal vein.
  • Whether obese or not, those with higher circulating insulin levels “…have markedly increased rates of hepatic de novo lipogenesis.” That means their livers are making fat. That fat (triglycerides or triacylglycerol) will be either burned in the liver for energy (oxidized), pushed into the blood stream for use elsewhere, or stored in the liver. Fatty acids are components of triglycerides. Excessive fatty acid intermediaries in liver cells—diglycerides and ceramide—are thought to interfere with insulin’s action, i.e., contribute to insulin resistance in the liver.
  • “Fasting plasma glucose concentration depends entirely on the fasting rate of hepatic [liver] glucose production and, hence, on its sensitivity to suppression by insulin.”
  • Physical activity, low-calorie diets, and thiazolidinediones reduce the pancreas’ insulin output and reduce liver fat levels.
  • Most T2 diabetics have above-average liver fat content. MRI scans are more accurate than ultrasound for finding it.
  • T2 diabetics have on average only half of the pancreas beta cell mass of non-diabetics. As the years pass, more beta cells are lost. Is the a way to preserve these insulin-producing cells, or to increase their numbers? “…it is conceivable that removal of adverse factors could result in restoration of normal beta cell number, even late in the disease.”
  • “Chronic exposure of [pancreatic] beta cells to triacylglycerol [triglycerides] or fatty acids…decreases beta cell capacity to respond to an acute increase in glucose levels.” In test tubes, fatty acids inhibit formation of new beta cells, an effect enhanced by increased glucose concentration.
  • There’s a fair amount of overlap in pancreas fat content comparing T2 diabetics and non-diabetics. It may be that people with T2 diabetes are somehow more susceptible to adverse effects of the fat via genetic and epigenetic factors.
  • “If a person has type 2 diabetes, there is more fat in the liver and pancreas than he or she can cope with.”
  • Here’s Dr. Taylor’s Twin Cycle Hypothesis of Etiology of Type 2 Diabetes: “The accumulation of fat in liver and secondarily in the pancreas will lead to self-reinforcing cycles that interact to bring about type 2 diabetes. Fatty liver leads to impaired fasting glucose metabolism and increases export of VLDL triacylglcerol [triglycerides], which increases fat delivery to all tissues, including the [pancreas] islets. The liver and pancreas cycles drive onward after diagnosis with steadily decreasing beta cell function. However, of note, observations of the reversal of type 2 diabetes confirm that if the primary influence of positive calorie balance is removed, the the processes are reversible.”
diabetic diet, etiology of type 2 diabetes, Roy Taylor, type 2 diabetes reversal

Figure 6 from the article: Dr. Taylor’s Twin Cycle Hypothesis of Etiology of Type 2 Diabetes

  • The caption with Figure 6 states: “During long-term intake of more calories than are expended each day, any excess carbohydrate must undergo de novo lipogenesis [creation of fat], which particularly promotes fat accumulation in the liver.”
  • “The extent of weight gloss required to reverse type 2 diabetes is much greater than conventionally advised.” We’re looking at around 15 kg (33 lb) or 20% of body weight, assuming the patient is obese to start.  “The initial major loss of body weight demands a substantial reduction in energy intake. After weight loss, steady weight is most effectively achieved by a combination of dietary restriction and physical activity.”

Dr. Taylor doesn’t specify how much calorie restriction he recommends, but reading between the lines, I think he likes his 600 cals/day for eight weeks program. That will have a have a high drop-out rate. I suspect a variety of existing ketogenic diets may be just as successful and more realistic, even if it takes more than eight weeks. I wonder how many of the 11 “cures” from the 2011 study have persisted.

Steve Parker, M.D.

Reference: Taylor, Roy. Type 2 diabetes: Etiology and reversibility. Diabetes Care, April 2013, vol. 36, no. 4, pp:1047-1055.

Update: Some wild and crazy guys tried the Taylor method at home. Click for results.

What’s the Single Best Diet for T2 Diabetics?

Thinking about it...

Thinking about it…

DietDoctor has some ideas based on a recent scientific study:

new exciting Swedish study provides us with strong clues on how a person with diabetes should eat (and how to eat to maximize fat burning). It’s the first study to examine in detail how various blood markers change throughout the day depending on what a diabetic person eats.

The study examined the effects of three different diets in 19 subjects with diabetes type 2. They consumed breakfast and lunch under supervision in a diabetes ward. The caloric intake in the three diets examined was the same, but the diets differed in the following manner:

  1. A conventional low-fat diet (45-56% carbs)
  2. A Mediterranean diet with coffee only for breakfast (= similar to 16:8 intermittent fasting) and a big lunch (32-35% carbs)
  3. A moderate low-carbohydrate diet (16-24% carbs)

All participants tested all three diets, one diet each day in randomized order.

Click through for results. Hint: Carbohydrate restriction works.

Steve Parker, M.D.

Low Magnesium Intake Linked to Type 2 Diabetes

…according to an article at Diabetes Care.

Visit the Linus Pauling Institute for dietary sources of magnesium. It remains to be seen, however, whether purposefully increasing your magnesium consumption via food or supplements will prevent diabetes.