Advanced Mediterranean Diet

You have to stay in shape.  My grandmother, she started walking five miles a day when she was 60.  She’s 97 today and we don’t know where the hell she is.

-Ellen Degeneris

Researchers at Harvard and the University of Athens (Greece) report that the following specific components of the Mediterranean diet are associated with lower rates of death:

• moderate ethanol (alcohol) consumption
• low meat and meat product intake
• high vegetable consumption
• high fruit and nut consumption
• high ratio of monounsaturated fat to saturated fat
• high legume intake

Minimal, if any, contribution to mortality was noted with high cereal, low dairy, or high fish and seafood consumption. 

The researchers examined diet and mortality data from over 23,000 adult participants in the Greek portion of the European Prospective Investigation into Cancer and nutrition.  You’ll be hearing more about the EPIC study for many years.  Over an average follow-up of 8.5 years, 1,075 of participants died.  652 of these deaths were of participants in the lower half of Mediterranean diet adherence; 423 were in the upper half.

Alcohol intake in Greece is usually in the form of wine at mealtimes. 

The beneficial “high ratio of monounsaturated fat to saturated fat” stems from high consumption of olive oil and low intake of meat. 

It’s not clear if these findings apply to other nationalities or ethnic groups.  Other research papers have documented the health benefits of the Mediterranean diet in at least eight other countries over three continents. 

The researchers don’t reveal in this report the specific causes of death.  I expect those data, along with numbers on diabetes, stroke, and dementia, to be published in future articles, if not published already.  Prior Mediterranean diet studies indicate lower death rates from cardiovascular disease and cancer.   

Steve Parker, M.D.

Reference:  Trichopoulou, Antonia, et al.  Anatomy of health effects of the Mediterranean diet: Greek EPIC prospective cohort study.  British Medical Journal, 338 (2009): b2337.  DOI: 10.1136/bmj.b2337.

Additional Information:  Childs, Dan.  Take it or leave it?  The truth about 8 mediterranean diet staples.  ABC News online, June 24, 2009.  Accessed June 25, 2009.

Update June 26, 2009:

Here’s a direct quote from the study at hand:

Among the presumed beneficial components of the Mediterranean diet score, high consumption of all but fish and seafood was inversely associated with mortality, although none of these associations was statistically significant.

“. . . none of these associations was statistically significant.”  So I can understand some skepticism about this journal article. The researchers had to use some very sophisticated statistical manipulation to come up with the “healthy components” list. I’m not saying that’s wrong. I will admit that the statistical analysis is beyond my comprehension, so I’m trusting the authors and peer-review process to be honest and effective. My college statistics course was too many years ago.

The take-home point for me is that the health benefits of the Mediterranean diet probably stem from an overall combination of multiple foods rather than any single component.

Steve Parker, M.D.

And remember to exercise regularly, maintain a healthy weight (BMI 18.5-25), keep your blood pressure under 140/90, and don’t smoke.

-Steve

Two recent studies refute the notion that fish and omega-3 fatty acid consumption help prevent dementia.

Most dementias, such as Alzheimer disease, are progressive and incurable.  Observational studies over the last 10 years have suggested that adequate fish intake - possibly related to the omega-3 fatty acids in fish - would prevent at least some cases of dementia.  Fish are the main dietary source of omega-3 fatty acids. 

The Canadian study was relatively small, with 663 participants.  They looked mainly at blood levels of omega-3s, and found no association between blood levels of omega-3s and dementia.  APOE4 status didn’t matter.  For those of you worried about mercury contamination of fish: they found that people with the most mercury in the bloodstream had a lower rate of dementia.  Go figure.

Researchers in Rotterdam studied 5395 subjects over almost 10 years.  They found no association between dementia and total fish intake, type of fish eaten, and intake of omega-3s.

These results are clearly disappointing for those of us who deal with dementia patients and their families.  We’ll see even more dementia as the average age of Western populations creeps higher.  Looking at people over 90, about half of them have dementia, and 70% of those are Alzheimer disease that started years earlier.  

On the bright side, several studied have associated the Mediterranean diet with lower rates of dementia.  It’s looking like that benefit is not related to fish consumption. 

Steve Parker, M.D.

References:

Kroger, Edeltraut, et al.  Omega-3 fatty acids and risk of dementia: the Canadian Study of Health and Aging.  American Journal of Clinical Nutrition, 90 (2009): 184-192.

Devore, Elizabeth, et al.  Dietary intake of fish and omega-3 fatty acids in relation to long-term dementia risk.  American Journal of Clinical Nutrition, 90 (2009): 170-176.

Eubie Blake was a ragtime musician (piano), composer, and lyricist.  Upon reaching the age of 100, he said,

 ”If I’d known I was gonna live this long, I’d have taken better care of myself.”

Steve Parker, M.D.

The Institute of Medicine is widely expected to recommend higher intake levels of vitamin D in 2010.  I’m not waiting - I’m starting now. 

I have great respect for Monica Reinagel at NutritionData.com.  I decided to review the issue when I read that vitamin D is one of only three supplements she takes - the others are fish oil and calcium.  Like me, she relies on a variety of natural, whole foods for the myriad vitamins and other nutrients we need. 

It’s not easy to miss all the medical journal articles on the effects and benefits of vitamin D published over the last 10 years.  Many of you know the time-honored role of vitamin D: bone health, including prevention of osteoporosis.  The major new developments in the vitamin D story are its potential benefits in terms of lower risk of type 2 diabetes, cardiovascular disease, dementia, some cancers, autoimmune diseases, infections, deaths, and falls in the elderly.  [Diabetes prevention may also require calcium supplementation.]  And we need higher blood levels of vitamin D for those benefits. 

The Institute of Medicine currently recommends 200 IU (international units) per day for people under 50, 400 IU for people 50-70, with an upper intake level of 2,000 IU per day.  I assume those amounts refer to a combination of food (or supplements) and the vitamin D your skin makes (but how do we know that?). 

The new recommendation is expected to be around 1,000-2,000 IU per day.  It’s quite difficult to get close to that just with food.  With adequate sun exposure, we can make some vitamin D.  But the dermatologists have scared us out of the sun with horror stories of skin cancer.  I’ve seen some tragic cases in my own patients.  Skin covered with sunscreen doesn’t make vitamin D.  It can be difficult to get enough sun exposure, especially at higher latitudes in winter. 

I’ll even admit I’m a little concerned about sunlight accelerating the changes of aging on my face,neck, and hands.  I grew up in the South (U.S.) and saw plenty of sun-worshipping young women who at age 35 looked closer to 50. 

I’m picking up a vitamin D supplement next time I’m at the supermarket - 1000 IU/day.

Steve Parker, M.D.

References:

Monica Reinagel.  Vitamin D: Now I’m a Believer.  Nutrition Data Blog, May 1, 2008.

Internal Medicine News, vol. 42, No. 8, April 15, 2009, pages 1 and 7.

American Medical News, April 27, 2009, pages 21-22.

Doc Note: I dissent. A fast never prevents a fatness. I diet on cod

Go hang a salami; I’m a lasagna hog

Some men interpret nine memos

Campus Motto: Bottoms up, Mac

Do geese see God

Dennis sinned

Don’t nod

Do you have any favorites?

Yo-yo dieting isn’t so bad after all.

Ten years ago there was lots of hand-wringing in the medical community about the potential dire physical consequences of “weight cycling” - also known as yo-yo dieting.  You know, lose a bunch of weight, gain it back, lose it again, gain it back, etc.

Then you didn’t hear so much about it.  It was a bit of a fad.  Like “detoxing,” although certainly more legitimate. 

A recent study in the Archives of Internal Medicine reported on the cardiovascular and mortality effects of yo-yo dieting in women in the massive Nurses’ Health Study.  One in four of these women could be classified as weight cyclers.  The worst ones were defined as those who lost at least 9.1 kg ( 20 pounds) at least three times.

It turns out the weight cyclers had the same rates of death from cardiovascular disease or any cause as the women who didn’t cycle.  They did eventually gain more overall weight as they aged, compared to the non-cyclers. 

Note that this study investigated death rates only.  So there may have been effects on rates of high blood pressure, diabetes, gout, stroke, etc, that we wouldn’t know about. 

Steve Parker, M.D.

Field, Alison, et al.  Weight cycling and mortality among middle-aged or older women.  Archives of Internal Medicine, 169 (2009): 881-886.

“Walking is the best possible exercise.  Habituate yourself to walk very far.” 

“A strong body makes the mind strong.  As to the species of exercise, I advise the gun.  While this gives moderate exercise to the body, it gives boldness, enterprise and independence to the mind . . . Let your gun therefore be your constant companion of your walks.”

Thomas Jefferson, 1743-1826

[Source of second quote: American Rifleman magazine, p.14, April 2009]