Advanced Mediterranean Diet

The American Diabetes Association has just unveiled an online calculator that estimates your risk of developing type 2 diabetes, heart disease, or stroke over the next 30 years.  It’s at My Health Advisor.  Anyone can use it.

You use the calculator anonymously, although I assume they will capture the IP address of your computer.  You don’t have to know the following data about yourself, but the ADA says the results will be more accurate if you provide more information [certainly makes sense]:

• cholesterol levels: total, HDL, LDL
• most recent fasting plasma glucose level
• recent blood pressure
• results of oral glucose tolerance test
• hemoglobin A1c result
• estimate of average glucose levels

I have no idea of the accuracy of this calculator.  But I rather doubt the ADA would offer it without substantial validation.

I’m always trying to figure out how to motivate people to take better care of themselves.  This calculator could help.  The print-out of your results suggests ways you might reduce your risk. 

Remember that the Mediterranean diet is demonstrated to reduce risk of type 2 diabetes, heart attack, and stroke.

Steve Parker, M.D.

A low-carb, high-protein diet is associated with worse atherosclerosis,  at least in lab mice genetically predisposed to atherosclerosis.  It’s entirely unclear whether these findings apply to humans.

Researchers used a strain of lab mice that can develop atherosclerosis within months rather than the 20-30 years necessary for development in humans.  If the mouse model of atherosclerosis were identical to the human model, research with applicability to humans would be so much easier.  Investigators compared mice fed either a “Western” type diet or a low-carb, high-protein diet.  Both diets had about 43% of calories derived from fat.

One persistent criticism of Atkins-style diets is that they may contribute to human atherosclerosis via the saturated fats in animal sources of protein.  We don’t have a definite answer to that issue.  Even if the Diet-Heart Hypothesis is wrong, an Atkins-style diet could still cause or prevent atherosclerosis - or other illnesses for that matter - through mechanisms as yet unknown. 

After seriously questioning the Diet-Heart Hypothesis, I’m seeing very low-carb eating in a much more favorable light, at least for overweight people. 

HeartWire has a balanced article on the recent research, with quotes from Drs. Eric Westman and Jeff Volick, low-carb advocates.

Steve Parker, M.D.

Reference:  Busko, Marlene.  Atherosclerosis heightened in mice fed low-carb, high-protein diet.  HeartWire, August 26, 2009.

How do you live a long life? 

“Take a two-mile walk every morning before breakfast.”

                                                                -Harry S. Truman

Older adults in low- to middle-income countries seem to have a lower risk of dementia if they regularly eat fish, according to a new study in the American Journal of Clinical Nutrition.

This comes on the heels of another recent study questioning the anti-dementia protective effect of fish consumption.

Almost 15,000 people were surveyed in China, India, Cuba, Domincan Republic, Mexico, Peru, and Venezuela.  As fish intake increased - from never, to some days of the week, to most or all days of the week - dementia prevalence dropped by 19% for each increase of intake.  Data for the effect were less convincing for Indian populations. 

The prevalence of dementia also tended to rise with meat consumption.

Steve Parker, M.D.

Reference:  Albanese, Emiliano, et al.  Dietary fish and meat intake and dementia in Latin America, China, and India: a 10/66 Dementia Research Group population-based study.  American Journal of Clinical Nutrition, 90 (2009): 392-400.

Let me tell you the secret that has led me to my goal.  My strength lies solely in my tenacity.

                                                    -Louis Pasteur (1822-1895)

Major media outlets have been reporting in the last 24 hours two new scientific studies regarding dementia, exercise, and the Mediterranean diet.  The story has been covered by the Wall Street Journal, U.S. News and World Report, and Bloomberg. 

Regarding dementia prevention and the Mediterranean diet, the two studies are contradictory, as so often happens in science.  One study suggests that regular exercise coupled with Mediterranean diet reduces the rate of dementia better than either measure alone.

The French study involved 1,410 adults 65 and older followed for at least five years.  Ninety-nine cases of dementia developed.  Adherence to a Mediterranean diet was computed from a food-frequency questionnaire [how accurate is that in demented people?].  Mediterranean diet adherence was not associated with the risk for developing dementia, although the authors note that statistical power to detect a difference was limited.  In other words, with only 1,410 study subjects, there would have to be a fairly large difference in outcomes, for it to be detectable.

In New York, New York, investigators studied the combination of exercise and a Mediterranean-type diet as protection against developing Alzheimer Disease, the most common cause of dementia.  Both exercise and the Mediterranean diet previously had been associated individually with lower rates of dementia.  They studied 1,880 seniors over five years.

They found that high adherence to the Mediterranean diet - not middle-of-the-road adherence - was associated with a 40% lower risk of developing Alzheimer Disease.  MOR got you nowhere.

The higher the degree of exercise, the lower the risk - up to 33% lower - of Alzheimer’s, in a dose-response fashion.

Folks who were sedentary and didn’t adhere to the diet had a 19% risk of developing Alzheimer’s.  Those with high diet adherence and high physical activity had a 12% risk of Alzheimer’s.  So, about a 60% lowered risk if you did everything right.

I covered recently two studies indicating that omega-3 fatty acids and fish consumption may not have the dementia-prevention properties many of us hope for.

Other studies suggest that your risk of dementia can be reduced by:

• ongoing social engagement as you age 
• ongoing intellectual stimulation as you age
• avoidance of overweight and obesity in middle age

Clearly, diet and exercise prescriptions are no panacea for dementia.  We still need better preventative measures and cures.

Steve Parker, M.D.

References: 

Porter, Carrie.  Dementia studies find diet, exercise matter.  Wall Street Journal online, August 12, 2009.

Feart, Catherine, et al.  Adherence to a Mediterranean diet, cognitive decline, and risk of dementia.  Journal of the American Medical Association, 302 (2009): 638-648.

Scarmeas, Nikolaos, et al.  Physical activity, diet, and risk of Alzheimer Disease.  Journal of the American Medical Association, 302 (2009): 627-637.

In July, 2008, I wrote that eating slowly can increase meal satisfaction and reduce caloric intake (in normal-weight women, anyway).

Monica Reinagel in her Nutrition Data Blog brought to my attention a recent scientific article examining the effect of bite size and “oral processing time” on food intake.  ”Oral processing time” must refer to how long food is in your mouth. 

Twenty-two healthy people were given chocolate custard in various amounts:  small bite size (5 gram), large bite size (15 gram), or ad lib (subject’s choice).  They were directed how long to keep it in their mouths - three or nine seconds - before swallowing.

The researchers found that using smaller bite size and keeping food in the mouth longer lead to significantly less custard intake.  Nine to 18% less. 

I don’t think we’ll ever have a good study testing these ideas as weight-control measures in overweight people over three months.  How do you force people to take smaller bites and chew more or longer before swallowing?  How would you monitor compliance? 

But every overweight person could easily conduct the experiment on himself.  Why not give it a try?

Steve Parker, M.D. 

Reference:  Zijlstra, Nicolein, et al.  Effect of bit size and oral processing time of a semisolid food on satiation.  American Journal of Clinical Nutrition, 90 (2009): 269-275.

Dentists are considering a return to an old theory that dietary carbohydrates first cause dental diseases, then certain systemic chronic diseases, according to a review in the June 1, 2009, Journal of Dental Research. 

We’ve known for years that some dental and systemic diseases are associated with each other, both for individuals and populations.  For example, gingivitis and periodontal disease are associated with type 2 diabetes and coronary heart disease.  The exact nature of that association is not clear.  In the 1990s it seemed that infections - chlamydia, for example - might be the unifying link, but this has not been supported by subsequent research.     

The article is written by Dr. Philippe P. Hujoel, who has been active in dental research for decades and is affiliated with the University of Washington (Seattle).  He is no bomb-throwing, crazed, radical. 

The “old theory” to which I referred is the Cleave-Yudkin idea from the 1960s and ’70s that excessive intake of fermentable carbohydrates, in the absence of good dental care, leads both to certain dental diseases - caries (cavities), periodontal disease, certain oral cancers, and leukoplakia - and to some common systemic chronic non-communicable diseases such as coronary heart disease, type 2 diabetes, some cancers, and dementia.  In other words, dietary carbohydrates cause both dental and systemic diseases - not all cases of those diseases, of course, but some.   

Dr. Hujoel does not define “fermentable” carbohydrates in the article.  My American Heritage Dictionary defines fermentation as:

1. the anaerobic conversion of sugar to carbon dioxide and alcohol by yeast
2. any of a group of chemical reactions induced by living or nonliving ferments that split complex organic compunds into relatively simple substances

As reported in David Mendosa’s blog at MyDiabetesCentral.com, Dr. Hujoel said, “Non-fermentable carbohydrates are fibers.”  Dr. Hujoel also shared some personal tidbits there. 

In the context of excessive carbohydrate intake, the article frequently mentions sugar, refined carbs, and high-glycemic-index carbs.  Dental effects of excessive carb intake can appear within weeks or months, whereas the sysemtic effects may take decades. 

Hujoel compares and contrasts Ancel Keys’ Diet-Heart/Lipid Hypothesis with the Cleave-Yudkin Carbohydrate Theory.  In Dr. Hujoel’s view, the latest research data favor the Carbohydrate Theory as an explanation of many cases of the aforementioned dental and systemic chronic diseases.  If correct, the theory has important implications for prevention of dental and systemic diseases: namely, dietary carbohydrate restriction.

Adherents of the paleo diet and low-carb diets will love this article; it supports their choices.

I agree with Dr. Hujoel that we need a long-term prospective trial of serious low-carb eating versus the standard American high-carb diet.  Take 20,000 people, randomize them to one of the two diets, follow their dental and systemic health over 15-30 years, then compare the two groups.  Problem is, I’m not sure it can be done.  It’s hard enough for most people to follow a low-carb diet for four months.  And I’m asking for 30 years?!   

Dr. Hujoel writes:

Possibly, when it comes to fermentable carbohydrates, teeth would then become to the medical and dental professionals what they have always been for paleoanthropologists: “extremely informative about age, sex, diet, health.”

Dr. Hujoel mentioned a review of six studies that showed a 30% reduction in gingivitis score by following a diet moderately reduced in carbs.  He mentions the aphorism: “no carbohydrates, no caries.”  Anyone prone to dental caries or ongoing periodontal disease should do further research to see if switching to low-carb eating might improve the situation. 

Don’t be surprised if your dentist isn’t very familiar with the concept.  Has he ever mentioned it to you?

Steve Parker, M.D.,

author of The Advanced Mediterranean Diet and the Diabetic Mediterranean Diet blog

Reference:  Hujoel, P.  Dietary carbohydrates and dental-systemic diseases.  Journal of Dental Research, 88 (2009): 490-502.

Mendosa, David.  Our dental alarm bell.  MyDiabetesCentral.com, July 12, 2009.

A report released last week found that obese individuals in the U.S. spend an extra $1,429 yearly on healthcare compared to normal-weight people.  Furthermore, total U.S. cost of treating obesity-related conditions was $147 billion in 2008.

Unsure if you’re overweight or obese?  Find out with one of the body mass index calculators available on the Internet.

Are you obese and fed up with the extra expense?  Are you already suffering from overweight-related medical conditions?  If so, read my document on how to prepare for weight loss, then get started soon. 

Well-begun is half done.

Steve Parker, M.D.

Author of The Advanced Mediterranean Diet and the Diabetic Mediterranean Diet Blog

Reference:  Finkelstein, E.A., et al.  Annual medical spending attributable to obesity: Payer and service-specific estimates.  Health Affairs, 28 (2009): w822-w831.

From a certain point onward there is no longer any turning back.  That is the point that must be reached.

                                                                 -Franz Kafka