Category Archives: Stroke

Fat or Fit: Which Is Healthier?

Men live longer if they improve or maintain their fitness level over time, according to research out of the Cooper Clinic in Dallas, Texas. Part of that improved longevity stems from reduced risk of death from cardiovascular disease such as heart attack and stroke.

Compared with men who lose fitness with aging, those who maintained their fitness had a 30% lower risk of death; those who improved their fitness had a 40% lower risk of death. Fitness was judged by performance on a maximal treadmill exercise stress test.

Body mass index over time didn’t have any effect on all-cause mortality but was linked to higher risk of cardiovascular death. The researchers, however, figured that losses in fitness were the more likely explanation for higher cardiovascular deaths. In other words, as men age, it’s more important to maintain or improve fitness than to lose excess body fat or avoid overweight.

Steve Parker, M.D.

Reference: Lee, Duck-chul, et al. Long-term effects of changes in cardiorespiratory fitness and bodly mass index on all-cause and cardiovascular disease mortality in men. Circulation, 124 (2011): 2,483-2,490

Tuna Preserves Brain Blood Flow In People Over 65

Among people over 65, consumption of tuna/other fish is associated with preserved blood flow to the brain, according to a 2008 research report in the journal Neurology.

“Silent” brain infarcts – tiny strokes that are not obvious – are very common with advancing age. If a group of people 65 and older is MRI scanned and found to have no strokes, MRI scans performed five years later will show tiny strokes in 20% of them. Almost 90% of these new strokes are simply incidental findings without clinically evident stroke or transient ischemic attack.

As the authors point out:

Subclinical infarcts and white matter abnormalities are considered to be of vascular origin, presumably resulting from occlusion of small arteries in the brain and subsequent ischemia.

These subclinical strokes, along with brain white matter abnormalities, are not benign. They are associated eventually with impairment in thinking and behavior, and with higher risk of future obvious stroke.

Eating tuna or other broiled or baked fish tends to raise plasma omega-3 fatty acid levels and is associated with lower stroke risk and dementia and Alzheimer disease. Researchers wondered if fish consumption affected the risk of subclinical brain infarcts or other subclinical brain abnormalities.

Methodology

Scientists studied 3,660 participants over 65 years old in the Cardiovascular Health Study, by MRI scanning, lab testing, physical exam, and food frequency questionnaire. Five years later, 2,313 were rescanned. Hospital and clinic records were reviewed. Participants were men and women in four U.S. communities. Fish intake was classified as to whether tuna, other broiled or baked fish, and fried fish or fish sandwiches (fish burgers). In a subset of participants, blood levels of omega-3 fatty acids were measured.

Conclusions of the Scientists

Among older adults, modest consumption of tuna/other fish, but not fried fish, was associated with lower prevalence of subclinical infarcts and white matter abnormalities on MRI examinations. Our results add to prior evidence that suggest that dietary intake of fish with higher eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA] content, and not fried fish intake, may have clinically important health benefits.

…the results of the present article support the growing evidence that the type of fish meal consumed is important for obtaining the health benefits of fish consumption.

Discussion

The fish with higher omega-3 fatty acids, such as EPA and DHA, are the cold-water fatty fish such as albacore tuna, salmon, trout, sardines, anchovies, herring, halibut, sea bass, swordfish, and mackerel. These are sometimes referred to as dark meat fish or oily fish. These are the same types of fish most closely associated with lower rates of coronary artery disease and sudden cardiac death.

The types of fish used in fish sticks, fish burgers, and other fried fish meals are typically low in omega-3 fatty acids.

If you choose to eat fish for the health benefits, aim for two servings per week of cold-water fatty fish. The Friday night all-U-can-eat fried catfish buffet doesn’t cut it.

Steve Parker, M.D.

Reference: Virtanen, J.K., et al. Fish consumption and risk of subclinical brain abnormalities on MRI in older [U.S.] adults. Neurology, 71 (2008): 439-446.

It’s Not Too Late to Get Healthier, Even if Middle-Aged

Are your eventual health problems a matter of fate by the time you reach middle age?

A study from the Medical University of South Carolina asked whether middle-aged folks could improve their health and longevity by making healthful changes in lifestyle.  15,708 study participants, ages 45-64, were surveyed with regards to four “healthy lifestyle” components, namely:

  • five or more fruits and vegetables daily
  • regular exercise
  • healthy weight range (BMI 18.5-29.9)
  • no current smoking

When first surveyed, 8.5% of the participants had all four of the healthy lifestyle components.  When surveyed six years later, 8.4% of the remainder had adopted these four healthy lifestyle features.  Overall death rate and cardiovascular disease events were monitored over the next four years.  Compared to the study participants who did not adopt a healthy lifestyle, the new adopters had a 40% lower incidence of death from all causes and 35% less cardiovascular disease events.

So middle-aged people can improve their longevity and avoid cardiovascular disease by making healthy lifestyle changes.  These improvements are very significant in degree and comparable to, if not better than, results seen with many expensive medications and invasive medical procedures.

Why not make some changes today?

Steve Parker, M.D.

References: King, Dana E., et al.  Turning Back the Clock: Adopting a Healthy Lifestyle in Middle Age.  American Journal of Medicine, 120(2007): 598-603.

Eye-Popping Statistics

I often talk to people interested in improving their health or losing weight via lifestyle modification, mostly changes in diet and exercise.  Many of them are motivated by health-related facts.  Here is a smattering of facts I compiled in 2008 (so some are outdated), starting out worrisome and ending hopeful: 

  • 65% of U.S. adults are overweight or obese.  Half are overweight, half are obese. 

  • 12% of deaths in the U.S. are due to lack of regular physical activity – 250,000 deaths yearly.

  • 11% of U.S. adults have diabetes mellitus.

  • 24 million in the U.S. have diabetes.  Another 57 million have pre-diabetes, a condition that increases your risk for diabetes.

  • 23% of U.S. adults over 60 have diabetes. 

  • 85% of people with type 2 diabetes are overweight.

  • 200,000 yearly deaths in the U.S. are due to obesity.

  • Excess body fat causes 14 to 20% of all cancer-related deaths in the U.S.

  • 550,000 people die yearly of cancer in the U.S. 

  • Obesity-related cancers in men: prostate and colorectal.  Obesity-related cancers in women: endometrial (uterine), cervix, ovary, breast.  Both sexes: kidney, esophageal adenocarcinoma.

  • 20% of us in the U.S. will die of cancer.

  • Lifetime risk of developing invasive cancer in the U.S. is four in 10 (a little higher in men, a little lower in women).

  • At least one-half of high blood pressure cases are caused by excess body fat.  Every 20 pounds of excess fat increases blood pressure by two to three points.

  • Peak aerobic power (a measure of physical fitness) decreases by 50% between age 20 and 65.

  • Middle-aged and older people through regular exercise can increase their aerobic power by 15 to 20%, equivalent to a 10 or 20-year reduction in biological age. 

  • Regular aerobic exercise reduces blood pressure by 8 to 11 points.  

  • Have you already had a heart attack?  If so, regular exercise reduces the odds of fatal recurrence by 25% and adds two to three years to life.

  • The Mediterranean diet is associated with lower incidence of cancer (colon, breast, prostate, uterus), cardiovascular disease (e.g., heart attacks), and dementia (both Alzheimers and vascular types). 

  • High fruit and vegetable consumption protects against cancer of the lung, stomach, colon, rectum, oral cavity, and esophagus.  The protective “dose” is five servings a day.

  • Coronary artery disease is the cause of heart attacks and many cases of sudden cardiac death.  Legume consumption lowers the risk of coronary artery disease.  The protective dose is four servings of legumes a week. 

  • Whole grain consumption is associated with reduced risk of coronary artery disease (e.g., heart attacks), lower risk of death, lower incidence of type 2 diabetes and several cancers.  The protective dose is three servings a day. 

The good news is that we can significantly reduce our risk of premature death and common illnesses such as high blood pressure, cancer, diabetes, coronary artery disease, and dementia.  How?  Weight management, diet modification, and physical activity.     

Steve Parker, M.D.

Evidence In Favor of Healthfulness of Whole Grains

I bought a sack of potatoes the other day.  The advertising on the sack proclaimed   these potatoes as “Gluten-Free!”.  As if other potatoes have gluten (they don’t).

In these days of gluten-free this and gluten-free that, the health benefits of grains—especially wheat—are being questioned.

A 2008 review article in a scientific journal confirmed the association between high whole grain intake and reduced incidence of cardiovascular disease.  Heart disease and strokes (subsets of cardiovascular disease) are the first and fourth leading causes of death, respectively, in the U.S.

The article authors, Philip Mellen, Thomas Walsh, and David Herrington, reviewed the scientific literature on the subject and found seven pertinent published observational studies.  Study participants were divided into those with high average whole grain intake (2.5 servings per day) and those with low average intake (0.2 servings a day, or 1 serving every 5 days).  Compared with low intake, participants with high intake had 21% lower risk of cardiovascular disease events, such as heart disease, stroke, and death from cardiovascular disease.

Refined grain intake, such as standard white bread, was not associated with cardiovascular disease one way or the other.

The authors conclude, “There is a consistent, inverse association between dietary whole grains and incident cardiovascular disease…and clinicians should redouble efforts to incorporate clear messages on the beneficial effects of whole grains into public health and clinical practice endeavors.”

I’ll be the first to admit that observational studies don’t prove that whole grains reduce the risk of cardiovascular disease.  They identify an association that should lead to additional testing of the hypothesis.  I don’t see any proof on the foreseeable horizon.

If heart attacks and strokes ran in my blood lines (genes), I’d try to incorporate two or three daily servings of whole grain into my diet, assuming I had no good reasons to avoid grains.

That being said, I’m also convinced that many can live long health lives without grains.

Steve Parker, M.D.

References and resources:

Mellen, Philip, et al.  Whole grain intake and cardiovascular disease: A meta-analysis.  Nutrition, Metabolism & Cardiovascular Diseases, 18, (2008): 283-290.

The Whole Grains Council.  Learn more about the benefits of various whole grains and how to find whole grain products.  Many recipes here, plus links to hundreds of recipes at other websites.

Alcohol Habit (Especially Wine) Starting in Middle-Age Reduces Heart Attack and Stroke

Jesus turned water into wine at a wedding.  His mother asked him to do it.  Of all the miracles he performed and could have performed, I wonder why this is the first one recorded in the Holy Bible.

We have known for years that low or moderate alcohol consumption tends to lower the risk of cardiovascular disease such as heart attack and stroke, and prolongs life span.  Physicians have been hesitant to suggest that nondrinkers take up the habit.  We don’t want to be responsible for, or even accused of, turning someone into an alcoholic.  We don’t want to be held accountable for someone else’s drunken acts.  Every well-trained physician is quite aware of the ravages of alcohol use and abuse.  We see them up close and personal in our patients.

A scientific study from a few years ago, however, lends support to a middle-aged individual’s decision to start consuming moderate amounts of alcohol on a regular basis.  It even provides a positive defense if a doctor recommends it to carefully selected patients.

This research, by the way, was supported by a grant from the National Heart, Lung, and Blood Institute, not the wine/alcohol industry.

Methodology

Researchers at the Medical University of South Carolina examined data on 15,637 participants in the Atherosclerosis Risk in Communities (ARIC) study over a 10-year period.  These men and women were 45 to 64 years old at the time of enrollment, living in four communities across the U.S.  Of the participants, 27% were black, 73% nonblack, 28% were smokers, and 80% of them had high blood pressure, high cholesterol, or diabetes.

Out of 15,637 participants at the time of enrollment, 7,359 indicated that they didn’t drink alcohol.  At baseline, these 7,359 had no cardiovascular disease except for some with high blood pressure.    Subsequent interviews with them found that six percent of the nondrinkers – 442 people – decided independently to become moderate alcohol drinkers.  Or at least they identified themselves as such.

“Moderate” intake was defined as 1-14 drinks per week for men, and 1-7 drinks a week for women.  Incidentally, 0.4% of the initial non-drinking cohort – 21 people – became self-identified heavy drinkers.

93.6% of the 7,359 non-drinkers said that they continued to be non-drinkers.  These 6,917 people are the “persistent nondrinkers.”

Type of alcohol consumed was also surveyed and broken down into 1) wine-only drinkers, or 2) mixed drinkers: beer, liquor, wine.

Researchers then monitored health outcomes for an average of 4 years, comparing the “new moderate drinkers” with the “persistent nondrinkers.”

Results

  •  Over 4 years, 6.9% of the new moderate drinkers suffered a cardiovascular event, defined as a heart attack, stroke, a coronary heart disease procedure (e.g, angioplasty), or death from cardiovascular disease.
  • Over 4 years, 10% of the persistent nondrinkers suffered a cardiovascular event.
  • The new moderate drinkers were 38% less likely than persistent nondrinkers to suffer a new cardiovascular event (P = 0.008, which is a very strong association).  The difference persisted even after adjustment for demographic and cardiovascular risk factors.
  • There was no difference in all-cause mortality (death rate) between the new moderate drinkers and the persistent nondrinkers.
  • New  drinkers had modest but statistically significant improvements in HDL and LDL cholesterol and mean blood pressure compared with persistent nondrinkers.
  • 133 new moderate drinkers consumed only wine
  • 234 new moderate drinkers consumed mixed types of alcohol
  • Wine-only drinkers were 68% less likely than nondrinkers to suffer a cardiovascular event.
  • “Consumers of moderate amounts of beer/liquor/mixed (which includes some wine) tended to also be less likely to have had a subsequent cardiovascular event than nondrinkers…but the difference was not significant.”

A Few Study Limitations

  • Four years is a relatively brief follow-up, especially for cancer outcomes.  Alcohol consumption is associated with certain types of cancer.
  • If moderate alcohol consumption indeed lowers death rates as suggested by several other studies, this study may not have lasted long enough to see it.
  • The alcohol data depended on self-reports.

Take-Home Points

The study authors cite four other studies that support a slight advantage to wine over other alcohol types.  It’s a mystery to me why they fail to stress the apparent superiority of wine in the current study.  Several other studies that found improved longevity or cardiovascular outcomes in low-to-moderate drinkers suggest that the type of alcohol does not matter.  Perhaps “the jury is still out.”  In the study at hand, however, it is clear that the reduced cardiovascular disease rate in new moderate drinkers is associated with wine.

In all fairness, other studies show no beneficial health or longevity benefit to alcohol consumption.  But at this point, the majority of published studies support a beneficial effect.

Wine is a component of the traditional healthy Mediterranean diet.  The Mediterranean diet is associated with prolonged life span and reduced cardiovascular disease.  This study strongly suggests that wine is one of the causative healthy components of the Mediterranean diet.

Starting a judicious wine habit in middle age is relatively safe for selected people and may, in fact, improve cardiovascular health, if not longevity.

Now the question is, red or white.  Or grape juice?

Steve Parker, M.D.

Reference:  King, Dana E., et al.  Adopting Moderate Alchohol Consumption in Middle Age: Subsequent Cardiovascular Events.  American Journal of Medicine, 121 (2008): 201-206.

Mediterranean Diet Cuts Stroke Risk In Women

The journal Circulation in 2009 reported that the Mediterranean diet reduces risk of stroke in women by 13%. This supplements our prior knowledge that the healthy diet is associated with lower risk of coronary heart disease in both men and women.

Researchers in Boston analyzed the records of 74,886 middle-aged women in the Nurses’ Health Study to deteremine how closely they followed a Mediterranean diet pattern. They followed participants’ health status for 20 years, noting how many women developed stroke, coronary heart disease, and “cardiovascular death” (fatalities from strokes and coronary heart disease combined).

Compared with the women who adhered minimally to the Mediterranean diet pattern, the women with highest compliance had 13% fewer strokes. Consistent with earlier studies, the Mediterranean dieters had 39% lower risk of cardiovascular death and 29% lower risk for coronary heart disease (again, comparing the women with highest and lowest compliance).

Take-Home Points

To gain the health benefits of the Mediterranean diet, consider making changes to the way you eat.

Here are the characteristics of the traditional Mediterranean diet:

  • It maximizes natural whole foods and minimizes highly processed ones
  • Small amounts of red meat
  • Less than four eggs per week
  • Low to moderate amounts of poultry and fish
  • Daily fresh fruit
  • Seasonal locally grown foods with minimal processing
  • Concentrated sugars only a few times per week
  • Wine in low to moderate amounts, and usually taken at mealtimes
  • Milk products (mainly cheese and yogurt) in low to moderate amounts
  • Olive oil as the predominant fat
  • Abundance of foods from plants: vegetables, fruits, beans, potatoes, nuts, seeds, breads and other whole grain products

Steve Parker, M.D.

Reference: Fung, Teresa, et al. Mediterranean diet and incidence of and mortality from coronary heart disease and stroke in women. Circulation, 119 (2009): 1,093-1,100.

Documented Health Benefits of the Mediterranean Diet

The enduring popularity of the Mediterranean diet is attributable to three things:

1.Taste

2.Variety

3.Health benefits

For our purposes today, I use “diet” to refer to the usual food and drink of a person, not a weight-loss program.

 

The scientist most responsible for the popularity of the diet, Ancel Keys, thought the heart-healthy aspects of the diet related to low saturated fat consumption.He also thought the lower blood cholesterol levels in Mediterranean populations (at least Italy and Greece) had something to do with it, too.Dietary saturated fat does tend to raise cholesterol levels.

 

Even if Keys was wrong about saturated fat and cholesterol levels being positively associated with heart disease, numerous studies (involving eight countries on three continents) strongly suggest that the Mediterranean diet is one of the healthiest around.See References below for the most recent studies.

 

Relatively strong evidence supports the Mediterranean diet’s association with:

increased lifespan

lower rates of cardiovascular disease such as heart attacks and strokes

lower rates of cancer (prostate, breast, uterus, colon)

lower rates of dementia

lower incidence of type 2 diabetes

 

 

Weaker supporting evidence links the Mediterranean diet with:

slowed progression of dementia

prevention of cutaneous melanoma

lower severity of type 2 diabetes, as judged by diabetic drug usage and fasting blood sugars

less risk of developing obesity

better blood pressure control in the elderly

improved weight loss and weight control in type 2 diabetics

improved control of asthma

reduced risk of developing diabetes after a heart attack

reduced risk of mild cognitive impairment

prolonged life of Alzheimer disease patients

lower rates and severity of chronic obstructive pulmonary disease

lower risk of gastric (stomach) cancer

less risk of macular degeneration

less Parkinsons disease

increased chance of pregnancy in women undergoing fertility treatment

reduced prevalence of metabolic syndrome (when supplemented with nuts)

lower incidence of asthma and allergy-like symptoms in children of women who followed the Mediterranean diet while pregnant

Did you notice that I used the word “association” in relating the Mediterranean diet to health outcomes?Association, of course, is not causation.

 

The way to prove that a particular diet is healthier is to take 20,000 similar young adults, randomize the individualsin an interventional study to eat one of two test diets for the next 60 years, monitoring them for the development of various diseases and death.Make sure they stay on the assigned test diet.Then you’d have an answer for that population and those two diets.Then you have to compare the winning diet to yet other diets.And a study done in Caucasians would not necessarily apply to Asians, Native Americans, Blacks, or Hispanics.

 

Now you begin to see why scientists tend to rely on observationalrather than interventional diet studies.

 

I became quite interested in nutrition around the turn of the century as my patients asked me for dietary advice to help them lose weight and control or prevent various diseases.At that time, the Atkins diet, Mediterranean diet, and Dr. Dean Ornish’s vegetarian program for heart patients were all prevalent.And you couldn’t pick three programs with more differences!So I had my work cut out for me.

 

After much scientific literature review, I find the Mediterranean diet to be the healthiest for the general population.People with particular medical problems or ethnicities may do better on another diet. People with diabetes or prediabetes are probably better off with a carbohydrate-restricted diet, such as the Low-Carb Mediterranean Diet.

 

Dan Buettner makes a good argument for plant-based diets in his longevity book, The Blue Zones.The Mediterranean diet qualifies as plant-based.

 

Steve Parker, M.D.

 

     Sofi, Francesco, et al. Accruing evidence about benefits of adherence to the Mediterranean diet on health: an updated systematic review and meta-analysis. American Journal of Clinical Nutrition, ePub ahead of print, September 1, 2010. doi: 10.3945/ajcn.2010.29673

     Buckland, Genevieve, et al. Adherence to a Mediterranean diet and risk of gastric adenocarcinoma within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study. American Journal of Clinical Nutrition, December 9, 2009, epub ahead of print. doi: 10.3945/ajcn.2009.28209

     Fortes, C., et al. A protective effect of the Mediterraenan diet for cutaneous melanoma. International Journal of Epidmiology, 37 (2008): 1,018-1,029.

Sofi, Francesco, et al. Adherence to Mediterranean diet and health status: Meta-analysis. British Medical Journal, 337; a1344. Published online September 11, 2008. doi:10.1136/bmj.a1344

     Benetou, V., et al. Conformity to traditional Mediterranean diet and cancer incidence: the Greek EPIC cohort. British Journal of Cancer, 99 (2008): 191-195.

Mitrou, Panagiota N., et al. Mediterranean Dietary Pattern and Prediction of All-Cause Mortality in a US Population, Archives of Internal Medicine, 167 (2007): 2461-2468.

     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.

     Scarmeas, Nikolaos, et al. Mediterranean Diet and Mild Cognitive Impairment. Archives of Neurology, 66 (2009): 216-225.

Scarmeas, N., et al. Mediterranean diet and Alzheimer disease mortality. Neurology, 69 (2007):1,084-1,093.

     Fung, Teresa, et al. Mediterranean diet and incidence of and mortality from coronary heart disease and stroke in women. Circulation, 119 (2009): 1,093-1,100.

Mente, Andrew, et al. A Systematic Review of the Evidence Supporting a Causal Link Between Dietary Factors and Coronary Heart Disease. Archives of Internal Medicine, 169 (2009): 659-669.

     Salas-Salvado, Jordi, et al. Effect of a Mediterranean Diet Supplemented With Nuts on Metabolic Syndrome Status: One-Year Results of the PREDIMED Randomized Trial. Archives of Internal Medicine, 168 (2008): 2,449-2,458.

     Mozaffarian, Dariush, et al. Incidence of new-onset diabetes and impaired fasting glucose in patients with recent myocardial infarction and the effect of clinical and lifestyle risk factors. Lancet, 370 (2007) 667-675.

     Esposito, Katherine, et al. Effects of a Mediterranean-style diet on the need for antihyperglycemic drug therapy in patients with newly diagnosed type 2 diabetes. Annals of Internal Medicine, 151 (2009): 306-314.

     Shai, Iris, et al. Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet. New England Journal of Medicine, 359 (2008): 229-241.

     Martinez-Gonzalez, M.A., et al. Adherence to Mediterranean diet and risk of developing diabetes: prospective cohort study. British Medical Journal, BMJ,doi:10.1136/bmj.39561.501007.BE (published online May 29, 2008).

     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.

     Barros, R., et al. Adherence to the Mediterranean diet and fresh fruit intake are associated with improved asthma control. Allergy, vol. 63 (2008): 917-923.

     Varraso, Raphaelle, et al. Prospective study of dietary patterns and chronic obstructive pulmonary disease among US men. Thorax, vol. 62, (2007): 786-791.

DASH Diet Reduces Risk of Heart Disease and Stroke in Women

U.S News and World Report recently ranked the DASH diet as the No.1 Healthiest Diet.  Today I partly explain why.

The Dietary Approaches to Stop Hypertension (DASH) diet has been shown to lower blood pressure.  Another study associated a DASH-style diet with lower incidence of heart attack and stroke.

The DASH diet is low in total and saturated fats and cholesterol, moderate in low-fat dairy products, high in fruits and vegetables, low in salt, low in sweetened beverages, moderate in whole grains, and low in animal protein but has substantial amounts of plant protein from nuts and legumes.

The DASH diet was designed as a healthy way of eating, not a weight-loss diet.  It is promoted by the National Heart, Lung, and Blood Institute for the prevention and treatment of high blood pressure.  It is also included as an example of a healthy diet in the 2005 Dietary Guidelines for Americans.  Yet many people still have never heard of it.

Researchers affiliated with multiple Boston and Atlanta institutions looked at the participants in the massive Nurses Health Study.  88,517 middle-aged women free of stroke, diabetes, and coronary heart disease were followed between 1980 to 2004.  They filled out food frequency questionnaires designed to assess average food intake over the preceding year.  The researchers constructed a DASH diet score and graded all the study participants in terms of adherence or conformity to the ideal DASH diet.

Over the course of the study, there were 2129 cases of nonfatal heart attack, 976 deaths from coronary heart disease, and 2317 strokes.  (If you read the original study, please note that some numerical errors were corrected in a later journal issue.)

Women with the highest adherence to the DASH Diet had 24% lower risk for coronary heart disease, compared with the women who had the lowest conformity.  Again comparing the same two groups for stroke, the high-adherence women had 18% less incidence of stroke.  There were clear trends for less coronary heart disease and stroke as adherence to the DASH diet increased.

Blood samples were analyzed for a subset of participants.  Higher DASH compliance was significantly associated with lower plasma levels of interleukin-6 and C-reactive protein.  These are markers for the inflammation felt to underlie atherosclerosis and cardiovascular disease.  You want to avoid high inflammatory markers.  The DASH diet scores in this study were not associated with serum lipid changes, although other DASH studies found lower LDL cholesterol and an undesirable reduction in HDL cholesterol.

The researchers examined causes of death in participants, yet did not report any association – positive, negative, or neutral – with DASH score.  I wonder why?  It’s possible that higher DASH scores were associated with higher overall death rates even though they had fewer heart attacks and strokes.  I imagine they also had access to cancer death statistics.  Why no mention?  Academicians are under pressure to publish research reports.  Are they saving the mortality and cancer data for future articles?  Abscence of all-cause mortality numbers is a major weakness of this study.

The DASH diet is similar in composition to the traditional Mediterranean diet.  The main differences are that the Mediterranean diet ignores salt intake, allows wine and other alcohol, and places more emphasis on olive oil and whole grains.  The Mediterranean diet has numerous supportive studies showing prolonged lifespan and less chronic disease: fewer heart attacks and strokes, less cancer, less dementia.  And very recently the Mediterranean diet was associated with a lower incidence of type 2 diabetes mellitus.

Steve Parker, M.D.

References:

Fung, Teresa, et al.  Adherence to a DASH-Style Diet and Risk of Coronary Heart Disease and Stroke in Women.  Archives of Internal Medicine, 168 (2008): 713-720.

Your Guide to Lowering Your Blood Pressure with DASH, from the National Heart, Lung, and Blood Institute

Mediterranean Diet Linked to Fewer Strokes

The Mediterranean diet reduces the risk of strokes seen on brain MRI scans, according to a study last year in Annals of Neurology.

Brain researchers at various U.S. institutions studied a multi-ethnic population in upper Manhattan (the WHICAP cohort). Average age of the 707 study participants was 80. Baseline diet was determined by a questionairre. A Mediterranean diet score was calculated to quantify adherence—or lack thereof—to the Mediterranean diet. Participants without dementia at baseline underwent MRI scanning initially, then again an average of six years later.

What Did They Find?

One third of participants had MRI evidence for a stroke. Higher adherence to the Mediterranean diet was linked to significantly lower odds of stroke. Compared to those eating least like the Mediterranean diet, those with the highest adherence had 37% lower odds of an stroke being found on MRI scan. Those with medium adherence had 20% lower odds.

So What?

This is the first study to show such an association between strokes on an MRI scan and the Mediterranean diet. Be aware that you can find a stroke on an MRI scan in someone who thought they were perfectly healthy; in other words a clinically silent stroke. The authors note only one previous report finding lower risk of clinically obvious stroke with the Mediterranean diet, in women—I thought there were more.

This same group of researchers had previously demonstrated that higher compliance with the Mediterranean diet is linked to lower risk of Alzheimers disease and mild cognitive impairment.

If I wanted to protect my brain from stroke, I’d be sure follow a Mediterranean-style diet, keep my blood pressure under 140/90 mmHg, stay physically active, keep my weight under control, and not smoke. The Advanced Mediterranean Diet combines weight management, exercise, and the Mediterranean diet.

Steve Parker, M.D.

Reference: Scarmeas, N., Luchsinger, J., Stern, Y., Gu, Y., He, J., DeCarli, C., Brown, T., & Brickman, A. (2011). Mediterranean diet and magnetic resonance imaging-assessed cerebrovascular disease Annals of Neurology, 69 (2), 257-268 DOI: 10.1002/ana.22317