Is Estrogen Poisoning the Cause of the Obesity Epidemic?

Eating too much tofu?

Too much tofu?

James P. Grantham and Maciej Henneberg of the School of Medical Sciences (University of Adelaide, Adelaide, Australia) suggest that estrogen-like compounds in the environment are causing obesity. Read about their hypothesis in PLOS One. I don’t know if they’re right, but their idea deserves consideration.

A couple estrogen-like substances they mention are in soy and polyvinyl chloride (PVC). We ingest these xenoestrogens. I had not been aware that soy consumption is positively linked to obesity.

The authors don’t instill confidence by using weak references such as #22.

I didn’t see the trendy “endocrine disruptors” moniker in the article.

Read the whole enchilada.

Steve Parker, M.D.

Family Physician Robert Oh Attacked His Prediabetes With Low-Carb Paleo Diet

Robb Wolf’s version of the paleo diet plus stopping his statin drug was just the ticket for Robert Oh, M.D., to cure his prediabetes, or at least put it into remission. Dr. Oh couldn’t blame genetics, physical inactivity, or obesity for his prediabetes. He was very active with CrossFit and had a healthy BMI of 23 at the time of his diagnosis. everydayHEALTH has the story. A quote by Dr. Oh:

Since I was already doing everything in terms of fitness, I began to experiment with my nutrition. Being a CrossFit fanatic, I heard about the low-carb Paleo diet, which is popular in the CrossFit community. Based on gut instinct alone, I took the 30-day challenge described in Robb Wolf’s book The Paleo Solution. Even though I started at 150 lbs. on my 5’7” frame, at the end of 30 days, I had lost eight pounds of body fat and felt great. Most importantly, my hemoglobin A1C, a marker of glucose control, dropped back to normal.

We’ve known for a few years that statin drugs are linked to type 2 diabetes in some way. Is it possible that Dr. Oh’s prediabetes cure stems simply from his discontinuation of the statin? Yes. I’ve not seen any studies to tell us whether statin-associated diabetes is reversible, nor how quickly.

Steve Parker, M.D.

Why Do Diabetics Resist the Paleo Diet?

Dr. Ernie Garcia (MD) posted a passionate essay about his difficulty getting his patients with diabetes to follow a carbohydrate-restricted Paleolithic diet. He makes a good case for carbohydrate addiction. A few quotes:

Today I saw a lady at my office. Fairly typical middle-aged, over weight female with poorly controlled diabetes. She recently started on an insulin pump but her glucose control is no better at all. I had a suspicion why, and again started to question the details of what she eats. Of course, she eats carb after carb after carb. Whole wheat this, and low fat that. She has tried to cut the carbs in the past, and actually had pretty decent success, but quickly falls back into your carbilicious ways. Why? Why go back when a change in diet shows clear improvement in her sugars?

*   *   *

What do addicts do? They generally know what they do is bad for them, and they have periods of clarity where they do better. Eventually though, the pull of their drug of choice draws them back in. Or, they slip up and use just a little and BAM…right back to square one. They feel shame for their addiction, people look down upon them for it, and they wish so badly they could make a permanent change, but they always fall back into old habits. Now, imagine a heroin addict who is advised to control the addition by sticking with “moderation” because of course, everything is good in moderation right?

Another issue that type 2 diabetics have is that they’ve been eating copious carbohydrates for over 40 years. It’s hard to break any habit with that type of longevity. It doesn’t help that they’re immersed in a carb-centric culture.

RTWT.

Steve Parker, M.D.

 

Ever Heard “No Carbs, No Cavities”?

I didn’t think so. None of my dentists ever uttered those words. Conflict of interests, maybe? And the worst carbohydrates for your teeth seem to be sugars.

173 Years of U.S. Sugar Consumption

(Thanks to Dr. Stephan Guyenet and Jeremy Landen for this sugar consumption graph.)

MNT on September 16, 2014, published an article about the very prominent role of sugars as a cause of cavities, aka dental caries. This idea deserves much wider dissemination.

I’ve written before about the carbohydrate connection to dental health and chronic systemic disease. Furthermore, sugar-sweetened beverages are linked to 200,000 yearly worldwide deaths

Investigators at University College London and the London School of Hygiene & Tropical Medicine think the World Health Organization’s recommendation of a maximum of 10% total daily calories from “free sugar” should be reduced to 3%, with 5% (25 grams) as a fall-back position.

Six teaspoons of granulated table sugar (sucrose) is 25 grams. That should be enough daily sugar for anyone, right? But it’s incredibly easy to exceed that limit due to subtly hidden sugars in multiple foods, especially commercially prepared foods that you wouldn’t expect contain sugar. Chances are, for instance, that you have in your house store-bought sausage, salad dressings, and various condiments with added sugars such as high fructose corn syrup. Sugar’s a flavor enhancer.

tooth structure, paleo diet, caries, enamel

Cross-section of a tooth

The aforementioned “free sugar” are defined as any monosaccharides and disaccharides that a consumer, cook, or food manufacturer adds to foods. In the U.S., we just call these “added sugars” instead of free sugars. From the MNT article, “Sugars that are naturally present in honey, syrup, and fruit juices are also classed as free sugars.” Sugar in the whole fruit you eat is not counted as free or added sugar.

The London researchers found that—in children at least—moving from consuming almost no sugar to 5% of total daily calories doubled the rate of tooth decay. This rose with every incremental increase in sugar intake.

From the MNT article:

“Tooth decay is a serious problem worldwide and reducing sugar intake makes a huge difference,” says study author Aubrey Sheiham, of the Department of Epidemiology & Public Health at University College London. “Data from Japan were particularly revealing, as the population had no access to sugar during or shortly after the Second World War. We found that decay was hugely reduced during this time, but then increased as they began to import sugar again.”

I’m convinced. How about you?

Steve Parker, M.D.

What About Vegetarian Diets for Diabetes?

low-carb diet, spaghetti squash, paleobetic diet, diabetic diet

The spaghetti squash at top is related to pumpkins and zucchini

I was surprised to learn that well-known diabetes writer David Mendosa (Type 2 DM) has switched from a very low-carb diet to a low-carb vegetarian diet, eating no more than 50 grams/day of carbohydrate. Why?

For me the issue is that I don’t want to be responsible for harming sentient beings as much as I can avoid it while still following a healthy diet.

I can respect that. I’m sure he’s monitoring the effects of the diet on his blood sugars and weight. Probably his blood lipids, too.

It sounds like all David had to do was drop fish from his prior diet. He still eats eggs (whites only?), cheese, and full-fat yogurt, so I’d call him a lacto-ovo-vegetarian.

If you’re already convinced that the Paleolithic diet is the best one for people with diabetes, read no further.

What Is a Vegetarian Diet?

From UpToDate.com:

Vegetarian diets vary considerably depending on the degree of dietary restrictions. According to the strictest definition, a vegetarian diet consists primarily of cereals, fruits, vegetables, legumes, and nuts; animal foods, including milk, dairy products, and eggs generally are excluded. Several less restrictive vegetarian diets may include eggs and dairy products. Some vegetarian diets may be grouped as follows:

●Macrobiotic — Vegetables, fruits, legumes, and seaweeds are included in the diet, while whole grains, especially brown rice, are also emphasized. Locally-grown fruits are recommended. Animal foods limited to white meat or white-meat fish may be included in the diet once or twice a week.
●Semi-vegetarian — Meat occasionally is included in the diet. Some people who follow such a diet may not eat red meat but may eat fish and perhaps chicken.
●Lacto-ovovegetarian — Eggs, milk, and milk products (lacto = dairy; ovo = eggs) are included, but no meat is consumed.
●Lactovegetarian — Milk and milk products are included in the diet, but no eggs or meat are consumed.
●Vegan — All animal products, including eggs, milk, and milk products, are excluded from the diet. Some vegans do not use honey and may refrain from using animal products such as leather or wool. They also may avoid foods that are processed or not organically grown.

A 2012 poll in the U.S. estimated that 7% of adults eat at least one meal a week that does not include meat, fish or poultry, 4% do not eat meat, fish, or poultry, and 1–2% do not eat meat, fish, poultry, dairy products, or eggs. Roughly 5% of individuals in the UK, Germany, and Australia describe themselves as vegetarian.

Switching to the paleo diet often leads to increased vegetable and fruit consumption

A low-carb diet can still have plenty of vegetables

Are Vegetarian Diets Safe?

Vegetarians need to be careful to get enough high-quality protein, iron, vitamin B12, vitamin D, and perhaps calcium. B12 comes only from animal products, as far as I know. You can make vitamin D by exposing your skin to sufficient sunlight. Some vegetarians will need to consult a dietitian to ensure adequate nutrition. (BTW, all my comment about vegetarian diets apply to adults only—I don’t treat children, so I’m not up-to-date on their nutritional needs.)

I’ve written about vegetarian diets for diabetes before: here and here. Dr. Michael Greger couldn’t convince Dr. Harriet Hall (or me) that we should avoid eating all animal products.

The Grashow Question

Someone claiming to be Charles Grashow left a comment on one of my blogs recently:

As I’ve posted before, this [vegetarian macrobiotic diet] took Insulin Dependent T2D [patients] OFF MEDS within 21 days!

Seems much better – but then again this diet is vegan not paleo!

http://www.hoajonline.com/internalmedicine/2052-6954/2/3
Ma-Pi 2 macrobiotic diet intervention during 21 days in adults with type 2 diabetes mellitus, Ghana 2011

http://www.nutritionandmetabolism.com/content/11/1/39
The effect of the macrobiotic Ma-Pi 2 diet vs. the recommended diet in the management of type 2 diabetes: the randomized controlled MADIAB trial

http://www.hindawi.com/journals/jnme/2012/856342/
Medium- and Short-Term Interventions with Ma-Pi 2 Macrobiotic Diet in Type 2 Diabetic Adults of Bauta, Havana

SO – my question is this. Why do you not recommend this type of diet instead? Or does it not fit into your paradigm?

I responded:

Charles, that macrobiotic Ma-Pi 2 diet looks like it has significant potential. I quickly scanned your first link only. For those not familiar with the diet, here’s a description form your first link:

“Vegetarian Ma-Pi 2 macrobiotic diet, designed especially by Mario Pianesi for treating diabetic patients. Total volume of the Ma-Pi 2 diet consisted of 40-50% whole grains (rice, millet and barley), 35-40% vegetables (carrots, savoy cabbage, cabbage, chicory, onions, red radish, parsley), and 8% legumes (adzuki beans, chickpeas, lentils, black beans). As a complement we used gomasio (roasted ground sesame seeds with unrefined sea salt), fermented products (miso, tamari, umeboshi) and seaweeds (kombu, wakame, nori). Bancha tea (theine-free green tea) was the main liquid diet.”

“The assayed Ma-Pi 2 diet is lower in energy than the traditional one recommended for diabetic patients, but safe, with adequate satiating effect due to the high fiber content, adequate in protein (12% of the total energy), with an acceptable amino acid score, low in fat (15% of the total energy), and high in complex carbohydrates (73%). The diet has a high antioxidant capacity and a high content of bioactive compounds with recognized functional properties (Table 2). Foods were elaborated by culinary macrobiotic specialists from UPM, Italy, and offered at the hospital during breakfast, lunch, dinner and snacks. Unfortunately, the variety of vegetables was restricted because of limited availability.”

I wonder if that would be deficient in vitamin B12.

It looks like it would be worth a try for a type 2 diabetic under medical supervision (risk of hypoglycemia). I’d like to try a few meals with those ingredients, some of which I’ve never heard of, prepared by someone who knows what they’re doing. Unless I missed it in the link, it might be hard for the average person to replicate that study diet. If I understood correctly, the study participants stayed in a hospital for three weeks and meals were prepared for them.

I don’t have time to hit the other links right now.

-Steve

My Current Stance on Vegetarian Diets For Diabetes

I say “current stance” because I’ll change my mind based on scientific evidence as it becomes available.

I’m not convinced that any of the vegetarian diets is clearly superior to the other available “diabetic diets” in terms of quality of life, longevity, and avoidance of diabetes complications.

We have some evidence that some vegetarian diets may help control diabetic blood sugars and help reduce the need for diabetes medications, at least short-term.

If my diabetic patients want to try a vegetarian diet, I have no objections as long as these criteria are met:

  • it’s a well-designed diet that provides adequate nutrition (which may require a dietitian consultation)
  • blood sugars, hemoglobin A1c, body weight, and blood lipids are monitored periodically
  • the patient is able and willing to self-monitor blood sugars fairly frequently
  • physician oversight, especially for those taking diabetes drugs

Vegetarian diets can be very high in carbohydrate content, which potentially could wreck blood sugar control. If that happens, consider a vegetarian diet with fewer starches and sugars.

Steve Parker, M.D.

Do Sugar Substitutes Cause Overweight and T2 Diabetes?

We don’t know with certainty yet. But a recent study suggests that non-caloric artificial sweeteners do indeed cause overweight and type 2 diabetes in at least some folks. The study at hand is very small, so I wouldn’t bet the farm on it. I’m not changing any of my recommendations at this point.

exercise for weight loss and management, dumbbells

Too many diet sodas?

 

The proposed mechanism for adverse metabolic effects of sugar substitutes is that they alter the mix of germs that live in our intestines. That alteration in turn causes  the overweight and obesity. See MedPageToday for the complicated details. The first part of the article is about mice; humans are at the end.

Some quotes:

“Our results from short- and long-term human non-caloric sweetener consumer cohorts suggest that human individuals feature a personalized response to non-caloric sweeteners, possibly stemming from differences in their microbiota composition and function,” the researchers wrote.

The researchers further suggested that these individualized nutritional responses may be driven by personalized functional differences in the micro biome [intestinal germs or bacteria].

***

Diabetes researcher Robert Rizza, MD, of the Mayo Clinic in Rochester, Minn., who was not involved with the research, called the findings “fascinating.”

He noted that earlier research suggests people who eat large amounts of artificial sweeteners have higher incidences of obesity and diabetes. The new research, he said, suggests there may be a causal link.

“This was a very thorough and carefully done study, and I think the message to people who use artificial sweeteners is they need to use them in moderation,” he said. “Drinking 17 diet sodas a day is probably a bad idea, but one or two may be OK.”

I won’t argue with that last sentence! (Unless you have phenylketonuria and want to use aspartame.)

Finally, be aware that several clinical studies show no linkage between human consumption of non-caloric artificial sweeteners and overweight, obesity, and T2 diabetes.

Steve Parker, M.D.

Are Low-Carb Diets Lethal?

Adult life is a battle against gravity. Eventually we all lose.

Adult life is a battle against gravity.

Japanese researchers say low-carb diets are causing premature death. I’m skeptical.

It’s a critically important issue because many folks with diabetes restrict their carbohydrate consumption to keep their blood sugars under control. Maybe it’s crazy, but they think they’ll live longer and have fewer diabetes complications if their glucose readings are under 200 mg/dl (11.1 mmol/l) most of the time.

The potentially healthful side effects linked to low-carb eating include reduced weight, higher HDL cholesterol, and lower triglycerides and blood pressure. The aforementioned Japanese investigators wondered if the improved cardiovascular risk factors seen with low-carb diets actually translate into less heart disease and death.

How Was the Study At Hand Done?

The best way to test long-term health effects of a low-carb diet (or any diet) is to do a randomized controlled trial. You take 20,000 healthy and very similar people—not rodents—and randomize half of them to follow a specific low-carb diet while the other half all eat a standard or control diet. Teach them how to eat, make damn sure they do it, and monitor their health for five, 10, or 20 years. This has never been, and never will be, done in humans. In the old days, we could do this study on inmates of insane asylums or prisons.

What we have instead are observational studies in which people voluntarily choose what they’re eating, and we assume they keep eating that way for five or 10+ years. You also assume that folks who choose low-carb diets are very similar to other people at the outset. You depend on regular people to accurately report what and how much they’re eating. You can then estimate how much of their diet is derived from carbohydrate and other macronutrients (protein and fat), then compare health outcomes of those who were in the top 10% of carb eaters with those in the bottom 10%. (We’ve made a lot of assumptions, perhaps too many.)

Of the observational studies the authors reviewed, the majority of the study participants were from the U.S. or Sweden. So any true conclusions may not apply to you if you’re not in those countries. In looking for articles, they found no randomized controlled trials.

The observational studies estimated carb consumption at the outset, but few ever re-checked to see if participants changed their diets. That alone is a problem. I don’t know about you, but I’ve had significant changes in my diet depending on when I was in college and med school, when I was a bachelor versus married, when my income was higher or lower, and when I had young children versus teenagers. But maybe that’s just me.

The researchers looked at all-cause mortality, deaths from cardiovascular disease, and incidence of cardiovascular disease. They don’t bother to define cardiovascular disease. I assume heart attack, strokes, and peripheral vascular disease. (But aren’t aneurysms, deep vein thrombosis, and pulmonary embolism vascular diseases, too?) Wouldn’t you think they’d carefully define their end-points? I would. Since they were going to all this trouble, why not look at cancer deaths, too?

What Did the Investigators Conclude?

Very low-carbohydrate dieters had a 30% higher risk of death from any cause (aka all-cause mortality) compared to very high-carb eaters. The risk of cardiovascular disease incidence or death were not linked with low-carb diets. Nor did they find protection against cardiovascular disease.

Finally, “Given the facts that low-carbohydrate diets are likely unsafe and that calorie restriction has been demonstrated to be effective in weight loss regardless of nutritional composition, it would be prudent not to recommend low-carbohydrate diets for the time being.”

If Low-Carb Dieters Die Prematurely, What Are They Dying From?

The top four causes of death in the U.S. in 2011, in order, are:

  1. heart attacks
  2. cancer
  3. chronic lower respiratory tract disease
  4. stroke

You’ll note that two of those are cardiovascular disease (heart attacks and stroke). So if low-carb diets promote premature death, it’s from cancer, chronic lung disease, or myriad other possibilities. Seventy-five percent of Americans die from one of the top 10 causes. Causes five through 10 are:

  • accidents
  • Alzheimer disease
  • diabetes
  • flu and pneumonia
  • kidney disease
  • suicide

Problem is, no one has ever linked low-carb diets to higher risk of death from any specific disease, whether or not in the top ten. Our researchers don’t mention that. That’s one reason I’m very skeptical about their conclusion. If you’re telling me low-carb diets cause premature death, tell me the cause of death.

Another major frustration of mine with this report is that they never specify how many carbohydrates are in this lethal low-carb diet. Is it 20 grams, 100, 150? The typical American eats 250-300 grams of carb a day. If you’re going to sound the alarm against low-carb diets, you need to specify the lowest safe daily carb intake.

For most of my career—like most physicians—I’ve been wary of low-carb diets causing cardiovascular disease. That’s because they can be relatively high in total fat and saturated fat. In 2009, however, I did my own review of the scientific literature and found little evidence of fats causing cardiovascular disease.

If you’re looking for a reason to avoid carbohydrate-restricted diets, you can cite this study and its finding of premature death. I’m not convinced. I’ll turn it around on you and note this study found no evidence that low-carb diets cause cardiovascular disease. The risk of cardiovascular disease had been the traditional reason for physicians to recommend against low-carb diets.

Steve Parker, M.D.

Reference: Noto, Hiroshi et al. Low-Carbohydrate diets and all-cause mortality: A systematic review and meta-analysis of observational studies. PLoS One, 2013; 8(1): e55050

This Just In! Obesity Reduces Lifespan

I'm worried about the kid's future health

I’m worried about the kid’s future health, too

MedPageToday has the details. A quote:

In a computer modeling study, very obese men lost just over 8 years of life compared with normal-weight men, and very obese women lost as many as 6 years, Steven Grover, PhD, of McGill University, and colleagues reported online in the Lancet Diabetes and Endocrinology.

They also found that very obese men and women (defined as a body mass index [BMI] of 35 and higher) lost about 19 years of healthy life, defined as living free of chronic disease such as diabetes and cardiovascular disease.

Note that “very obese” in this context has a specific definition: body mass index 35 or higher. Calculate yours.

The number of life years lost to obesity and disease were highest for those who were very obese in young adulthood and presumably stayed obese for years. In other words, becoming very obese at age 25 is more threatening than onset 60.

I first got interested in weight loss in the 1990s when I had an office-based primary care medical practice. It was obvious that many of the medical problems I was treating were related to years of obesity. Believe me, you’re much better off preventing those problems via diet and exercise.

Click for The Lancet study abstract.

Steve Parker, M.D.

Paleo Diet Ranks Dead Last

…in U.S. News & World Report’s yearly ranking of common diets.

I have nothing to add to Tom Naughton’s excellent critique of the listicle.

FWIW, Woman’s World magazine ranked the paleo diet as America’s Best in 2013.

-Steve

Would You Believe Four in Ten U.S. Adults Will Develop Diabetes?

Like type 1 diabetics, many type 2's need insulin shots

Like type 1 diabetics, many type 2’s need insulin shots

Researchers affiliated with the U.S. Centers for Disease Control estimate that 40% of American adults will develop diabetes, mostly type 2. The CDC’s prior estimate was the one of every three Americans born in 2000 would develop diabetes. Some snippets from the article abstract:

On the basis of 2000—11 data, lifetime risk of diagnosed diabetes from age 20 years was 40·2% for men and 39·6% for women, representing increases of 20 percentage points and 13 percentage points, respectively, since 1985—89.

The number of life-years lost to diabetes when diagnosed at age 40 years decreased from 7·7 years in 1990—99 to 5·8 years in 2000—11 in men, and from 8·7 years to 6·8 years in women over the same period.

Years spent with diabetes increased by 156% in men and 70% in women.

The good news is that you can decrease your odds of type 2 diabetes via diet and exercise. The single most important issue in preventing type 2 diabetes is avoiding obesity.

Steve Parker, M.D.