Tag Archives: hearthealth

Extra-Virgin Olive Oil and Nuts for Prevention of Cardiovascular Disease

In our third and final post in recognition of National Olive Oil Month, today’s article will review research on primary prevention of cardiovascular disease using a Mediterranean-style diet.

The Mediterranean Diet loosely defined is inspired by the eating habits of those countries who surround the Mediterranean Sea, including Spain, Italy and Greece. This diet emphasizes high consumption of fruits and vegetables, as well as olive oil. There is more emphasis on fresh fish and less emphasis on red meats. Moderate wine consumption is also considered to be a component.

A group of researchers affiliated with the PREDIMED Study in Spain designed a study to examine the effects of a Mediterranean-style diet on the primary prevention of cardiovascular disease in a group considered to be at high cardiovascular risk.

Enrollees did not have a history of cardiovascular disease at the time of enrollment. The enrollees did have either type 2 diabetes, or at least 3 of the major risk factors of family history of premature coronary heart disease, high LDL, hypertension, low HDL, obese or overweight, or smoking.

Participants were randomly assigned to one of three groups- a Mediterranean diet supplemented with extra-virgin olive oil, a second group which followed a Mediterranean diet supplemented by nuts, or a third control group which was instructed to follow a low fat diet. Those in the extra-virgin oil group were instructed to consume at least four tablespoons of oil each day. Those in the nut-supplemented group received 30 grams of mixed nuts each day (almonds, hazelnuts, walnuts). Participants adherence to each assigned diet was assessed by a food questionnaire. Subjects were followed on average for nearly 5 years. Primary end point was death from cardiovascular causes, heart attack, or stroke.

The researchers discovered that the Mediterranean-style diet, when either supplemented with extra-virgin olive oil or nuts, was associated with a lower risk of major cardiovascular events over a period of 5 years, then was the low-fat control diet. In addition, among those who more closely adhered to the Mediterranean diet the cardiovascular benefit was greater.

Important points to consider regarding this study include- enrolled high risk subjects without a history of cardiovascular disease, and examined primary (not secondary) prevention. Also, these diets were not calorie restricted. Primary prevention is especially important, as that is what a lot of folks are concerned about.

This study leads to the veritable mountain of research showing that a proper diet can help or in this case prevent significant health issues. Perhaps give this some thought with the next trip to the grocery store or fast-food drive through window.

“Knowledge is the food of the soul.”–  Plato

(Source- New England Journal of Medicine 2018; 378)

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

 

 

Olive Oil Decreases Blood Pressure in Young Women

August is designated as National Olive Oil Month, and today’s post is the second in recognition of this healthy food. Today we examine the effect of a polyphenol-rich olive oil on blood pressure and the markers of inflammation in young women.

A group of researchers from Spain performed a double blind, randomized dietary intervention trial, to examine the effects of a polyphenol-rich olive oil diet on blood pressure, as well as markers of endothelial function and oxidative stress. The subject group was young women (average age 26 years) who had recently been diagnosed with either high-normal blood pressure, or Stage 1 hypertension.

The subjects began with a four month run-in period, during which a set Mediterranean-style diet was provided to all the participants to follow. After the four month run-in, the women were randomized to either a polyphenol-rich olive oil diet, or a polyphenol-poor olive oil diet, which was then followed for two months. After two months there was a 4 week wash out period, after which the groups were reversed and followed for an additional two months. While in the polyphenol-rich group, participants consumed about 30 mg/day of polyphenols from olive oil. 24 women completed the study.

The researchers discovered that the polyphenol-rich diet let to a significant decrease in both systolic (7.91 mm Hg) and diastolic (6.65 mm Hg) blood pressures. In addition, markers of oxidative stress (ADMA, ox-LDL) and inflammation (CRP) were significantly reduced.

The drop in blood pressure seen with the polyphenol-rich diet is profound, in that it is comparable to the drops in blood pressure one might see with some of the first line anti-hypertensive medications.

This study is important in that it studies a dietary intervention in women, a group that is often underrepresented in medical research. Also, this was a group with high-normal or the earliest stages of hypertension, not a group with more significant disease. It’s possible that in a population with much worse hypertension there may be even more profound improvement in blood pressure.

Incorporating olive oil into your daily diet appears to be a low-risk way to help lower blood pressure and improve vascular health.

“People with high blood pressure, diabetes- those are conditions brought about by lifestyle. If you change the life style, the conditions will leave.”–  Dick Gregory

(Source- American Journal of Hypertension, Volume 25 Number 12, December 2012)

This blog is a review of published and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone.

 

Blueberry Juice May Lower Blood Pressure

July 8th is National Blueberry Day, and out of respect for this tasty fruit today’s post will review a study which examined the effects of wild blueberry juice in a group of adult women at high risk for diabetes mellitus type 2.

Both wild and cultivated blueberries are native to North America. Depending on altitude, latitude and weather the peak of the blueberry crop can vary from May to August. In the US there are many blueberry festivals which celebrate this delicious fruit. In places like Bethlehem PA, Burgaw NC and South Haven MI, among many others, blueberry lovers gather to celebrate.

The skins of the blueberries contain anthocyanins, which have anti-oxidant properties. Wild blueberries have one of the highest levels of anti-oxidants among fruits and vegetables. In the U.S., Maine is the largest producer of lowbush or wild blueberries, and produces over 100 million pounds annually.

A group from Canada and the U.S. performed a study examining the effects of wild blueberry juice on various cardiometabolic markers. The study population had at least two risk factors for type 2 diabetes, and thus were higher risk.

The study design was a randomized trial, with a placebo control. The subjects drank 240 ml of juice made from lowbush (wild) blueberries, while the control group drank a placebo beverage which was color and flavor matched to the blueberry juice. The blueberries were harvested from Prince Edward Island, Canada. Participants drank the blueberry juice daily for a week, followed by an eight day washout period. Following that workout period, the study group became the control group and vice versa.

Several cardiometabolic markers were monitored during the course of the study, such as serum cholesterol, HDL, LDL, triglycerides, glucose, endothelial function, c-reactive protein, serum amyloid, among others. Vital signs included blood pressure were also monitored.

19 participants, all women, completed the study. The researchers discovered that while the wild blueberry juice did not significantly change cardiometabolic markers, it did lower systolic blood pressure 4.8 mm Hg (4%) compared to the placebo group. While a 4.8 mm Hg reduction in systolic blood pressure may not sound substantial, it is estimated that a reduction of only 3 mm Hg may reduce mortality from heart disease and stroke by 5-8%. 

Drinking the blueberry juice for only 7 days was probably not long enough to effect any significant change on metabolic markers. A longer study seems reasonable given the promising results of this study. This does appear to be a low-risk way to improve one’s health. 

“The smallest seed of faith is better than the largest fruit of happiness.”– Henry David Thoreau

(Source- BMC Nutrition 2017 3:45)

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

 

 

 

Blueberries and Metabolic Syndrome

July 8th is designated National Blueberry Day, and in recognition of this delicious fruit today’s post will examine a study just published in June on the effect of blueberry consumption on cardiovascular risk factors.

The US is the world’s largest producer of blueberries, producing more that twice the tonnage of blueberries annually than the 2nd largest producer, Canada. The largest blueberry producing state is Washington, followed by Georgia, Michigan and Oregon. Low bush or wild blueberries, and high bush or cultivated blueberries, are all native to North America. Many of the beneficial properties of blueberries are thought to be due to their anthocyanins. Anthocyanins are water-soluble pigments which may appear black, blue, purple or red. Plants rich in anthocyanins include black rice, blueberries and raspberries. Anthocyanins have anti-oxidant properties.

A research group from the UK and Harvard looked at the relationship between blueberry consumption and its effect if any on insulin resistance and markers of cardiometabolic function. A random controlled double blind study was performed, with 138 enrollees, randomly assigned to one of three groups- a group which consumed the dietary equivalent of one cup of fresh blueberries each day, a second group which consumed a dietary equivalent of 1/2 cup of fresh blueberries each day, while the third group consumed a placebo. It is important to note that the study subjects had all been diagnosed with metabolic syndrome and were overweight or obese. The study enrolled both men and women, ages 50-75.

The study lasted six months. The researchers discovered that while metabolic syndrome markers were not significantly changed by blueberry consumption, the group that consumed one cup of blueberries per day did show improvements in HDL (“good cholesterol”), endothelial function, and systemic arterial stiffness. It was estimated that a 13% reduction in future cardiovascular events was possible in the one cup per day group.

This is an important study, with one of the longer study periods (six months) completed to date. The study population had significant health issues, including metabolic syndrome and was older. Although the intervention did not change the insulin resistance numbers, it is possible that the study intervention was simply not long enough.

Metabolic syndrome is a cluster of conditions including elevated blood pressure, excessive fat around the waist, elevated triglyceride levels, and decreased HDL. Individuals with metabolic syndrome are at higher risk for heart attack and stroke, and metabolic syndrome is thought to be a precursor for Diabetes Mellitus Type 2.

Here is a well-designed study showing the benefits of a simple dietary intervention on metabolic syndrome. Next time you are considering something for dessert or a snack, put the cake, cookies and ice cream away and reach for blueberries instead. And buy local if possible, and support our farmers and propagators.

“There are eyes, to be sure, that give no more admission into the man than blueberries.”-    Ralph Waldo Emerson

(Source- American Journal of Clinical Nutrition 2019; 109)

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

 

Not Even One

May 31st is World No Tobacco Day, and today’s post will examine a study on the effects of cigarette smoking and risks of coronary heart disease and stroke.

Most folks are well aware of the adverse risks of smoking to health. The first Surgeon General’s Advisory Committee on Smoking and Health report was released in January of 1964. The committee had reviewed more than 7,000 articles related to smoking and disease, available in the medical literature at that time. The committee concluded that cigarette smoking was a cause of lung and laryngeal cancer in men, and a likely cause of lung cancer in women.

The percentage of American’s who smoke has dropped from roughly 42% of the population in 1964, to about 14% today. While these statistics are encouraging, tobacco use still accounts for about half a million deaths in the U.S. each year, and about five million death worldwide.

While most people agree on the health risks of cigarettes, what would be the risk of just one cigarette a day? Certainly the risk couldn’t be too high?

A research group from the UK set out to answer this same question. They performed a meta-analysis and systematic review of published studies from 1946 to 2015, eventually including 141 cohort studies. The researchers looked specifically at the risks of smoking on coronary heart disease and stroke.

When their analysis was completed, the results were astounding. For men, the relative risk of smoking a pack a day (20 cigarettes) on coronary heart disease was 2.04, while smoking only one cigarette a day still carried a 1.48 relative risk. So men who smoked only one cigarette a day still had 46% of the excess risk of those who smoked a full pack per day. The data for stroke was not much better, the relative risk for smoking 20 cigarettes daily was 1.64, while smoking only one cigarette a day still carried a 1.25 relative risk, which was 41% of the excess relative risk of those who smoked a pack a day.

The data for women is equally as grim. The relative risk for coronary heart disease in women who smoke a pack per day is 2.84, while one cigarette per day still has a relative risk of 1.57. So even just one cigarette has 31% of the excess risk of a full pack per day.

The data for women smokers relative to stroke are equally poor. For women who smoke a pack per day, the relative risk for stroke is 2.16, while one cigarette per day still yields a 1.31 relative risk. This means that the one cigarette per day female smoker still carries 34% of the excess risk of a full pack per day smoker, for stroke.

The 141 cohort studies included literally millions of subjects, a broad cross-section of the US population, and would seem applicable to the US population in general. It is crystal clear from these results that even one cigarette per day carries substantial risks, in this case increased risk of coronary heart disease and stroke, in both men and women.

“There is no safe dose of a carcinogen.”–  Rachel Carson

(Source- BMJ 2018:360:j3984)

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

 

 

 

Lose Weight and Eat More Fiber to Lower Blood Pressure

May is designated as National High Blood Pressure Education Month, and so today’s post focuses on blood pressure, and how it may be improved via two different lifestyle and dietary modifications.

According to statistics from the CDC, about 75 million Americans have hypertension, which is about one in three adults. Only about have of those with hypertension have it under control. The costs associated with high blood pressure are estimated at $50 billion each year. African-Americans are particularly at risk for hypertension, with about 46% afflicted.

First of all a meta-analysis from researchers in the Netherlands looked at 25 different random controlled trials including over 4800 subjects, examining the effect of weight loss on blood pressure. After pooling the data from these 25 studies, it was determined that a 5 kg weight loss (= 11 pounds) yielded an average 4.4 mm Hg drop in systolic blood pressure, and a 3.6 mm Hg drop in diastolic blood pressure. Weight loss was achieved by physical exercise, calorie restriction, or a combination of both. Larger blood pressure decreases were noted in those subjects who were already taking medicine for high blood pressure.

In addition to weight loss having a beneficial effect on blood pressure, it appears dietary fiber also has benefit. Researchers from Tulane University pooled data from 25 different studies, to examine the effects of dietary fiber on blood pressure. Nearly 1500 subjects were evaluated, with trials from the U.S., Canada, Europe, Australia and India included. The overall effect of dietary fiber on blood pressure was a 1.15 mm Hg drop in systolic blood pressure, and a 1.65 mm Hg drop in diastolic blood pressure. The drops in blood pressure were more significant in those patients with hypertension, with trials greater than or equal to eight weeks in duration, and in trials with fiber intake of 7.2-18.9 gm/day.

Therefore weight reduction and increased dietary fiber intake may be effective ways to help lower blood pressure, particularly in those who are currently diagnosed and being treated for hypertension. While certainly not a replacement for traditional hypertension therapy, losing weight and increasing fiber intake seem like simple lifestyle changes that could yield important benefits.

“One way to get high blood pressure is to go mountain climbing over molehills.”–  Earl Wilson

(Source- Journal of Hypertension, 2005, Vol 23 No. 3.  Hypertension, November 2003)

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

Physical Activity Lowers Women’s Heart RIsks

This week is National Women’s Health Week, and in recognition of this important week today’s post will look at a study in older women, examining the effect of physical activity on coronary heart disease.

A research group performed a prospective cohort study from subjects participating in the Women’s Health Initiative. Nearly 6000 women with an average age of 78 1/2 were enrolled, and were followed for up to five years. These were women without a history of heart attack or stroke.

The activity level of the women was measured by the use of a accelerometer that was worn on the right hip. This device is designed to capture measures of subject activity and mobility. Researchers found that light physical activity was associated with a dose-responsive reduced risk of cardiovascular disease and coronary heart disease in this cohort of older women. The results were considered to be statistically significant.

The group with the highest quartile of light physical activity was associated with a 42% reduced risk of heart attack or coronary death, compared to the group with the lowest quartile of light physical activity. Similarly, there was a 22% reduced risk of cardiovascular events in the highest quartile of light physical activity, compared to the lowest quartile of light physical activity group.

This was a well-designed study among a group of older women, a group that is often neglected in medical research. This was also a diverse population, including substantial numbers of black (33.5%) and Hispanic (17.6%) women. It is impressive that encouraging more activity, even of the “light” variety, yielded some very substantial results.

“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.”– Hippocrates

(Source- JAMA Network Open, 2019, 2(3))

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

Mediterranean Diet Good for Women’s Heart Health

May 12-18 is celebrated as National Women’s Health Week, and in recognition of this important week today’s post will examine research studying the effects of a Mediterranean-style diet on cardiovascular risk factors in women.

For those who are unfamiliar with the Mediterranean Diet, it is loosely based on the traditional cooking styles of those countries that border the Mediterranean Sea. Some of the important tenants of the diet include eating lots of vegetables and whole grains, using olive oil as a substitute for butter and margarine, eating more fish and less red meat, and choosing nuts as a healthy snack.

In a recently published paper, researchers affiliated with Harvard Medical School examined the effects of a Mediterranean-style diet upon cardiovascular risk factors in a group of women participants. This particular study involved nearly 26,000 women. To assess the women’s dietary habits, a food-frequency questionnaire which included 131 items was administered at enrollment in the study. The researchers then calculated what they termed the “Med Score” for each participant. The Med Score ranged in scale from 0 to 9, with a higher score indicating better adherence to the Mediterranean Diet. The subjects were then placed into three different categories (Low, Medium, High) based on their Med Score. Multiple lab markers were taken as well, including LDL, HDL, CRP, fibrinogen, and lipoprotein (a).

This group of women was then followed for about 12 years. They were monitored for cardiovascular events such as heart attack and stroke. The researchers discovered that the subjects in both the Medium Med Score group and the High Med Score group had significant cardiovascular risk reduction, compared to the Low Med Score group. The risk reduction was 28% in the High Med Score group, and 23% reduction in the Medium Med Score group, compared to the Low Med Score Group.

This is a very well done study, which adds to previous research on the benefits of the Mediterranean Diet. This is a large group of women, who were considered healthy at baseline, which is important to note. Here we have a relatively simple dietary modification that had a profound positive impact on women’s cardiovascular health. The Mediterranean Diet seems to be a low-risk diet, that is worthy of consideration by women, and men as well.

“No disease that can be treated by diet should be treated with any other means.”– Moses Maimonides

(Source- JAMA Network Open, 2018:1(8))

This bog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

 

 

Enjoy a Cup of Tea Today (or three)

April 21st is National Tea Day in the UK, and in recognition of this today’s post will examine research regarding tea consumption and cardiovascular outcomes.

Tea is one of the most widely consumed beverages in the world. Tea is derived from Carmellia sinesis leaves, and leaf buds. Carmellia sinesis is an evergreen shrub or small tree, which grows at elevation in warmer weather climates. Approximately 40% of the global tea production comes from China, with India producing about 22%. Other leading producers include Kenya, Sri Lanka, and Turkey. Turkey is the largest per capita consumer of tea, at 5 1/2 pounds per person per year. According to statistics from the Tea Association of the USA, Americans consumed over 84 billion servings of tea last year. Over 84% of that was black tea, with about 15% being green tea.

Tea is purported to have a range of health benefits, from cardiovascular benefits, to lowering risks of certain cancers, to improvement in cognitive health. Tea is composed of hundreds of bioactive compounds, including flavonoids. Flavonoids are thought to have antioxidant properties, and may be the source of some of the beneficial properties of tea.

Researchers in China performed a meta-analysis of published prospective observational studies to examine the relationship between tea consumption and various cardiovascular outcomes. Twenty-two different studies were included in the analysis, including participants from the US, Europe, and Asia. More than 850,000 subjects were enrolled in these various trials.

Researchers discovered that increased tea consumption was associated with a reduction in cardiac death, cerebral infarction, heart disease, intracerebral hemorrhage and stroke. More importantly, tea consumption was associated with a reduction in total mortality. These results were with a serving of three cups of tea per day.

This was a robust meta-analysis, with a large number of study participants, spanning the globe. Given these results, consider tea as a healthy beverage choice, and salute National Tea Day!

“There are few hours in life more agreeable than the hour dedicated to the ceremony known as afternoon tea.”  Henry James

(Source- European Journal of Epidemiology (2015) 30)

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.

Increasing Glucose Leads to Heart Attacks and Strokes

Today is Diabetes Alert Day, and in recognition our post will review a recently published study on change in fasting glucose levels and subsequent risk of heart attack, stroke and all-cause mortality.

A reasearch group in Korea analyzed data from over 260,000 Korean adults enrolled in the Korean Health Insurance Service. These were adults over 40 years old, and with no diagnosis of diabetes or cardiovascular disease at time of enrollment in the study. The study included both men and women.

At initial enrollment, subjects were divided into two groups- a normal fasting glucose group (glucose <100 mg/dL) and an impaired fasting glucose group (glucose 100-125.9 mg/dL). Data such as smoking status, body mass index, blood pressure, physical activity level, total cholesterol, and alcohol consumption was also collected.

The subjects had a second examination in two years. At this second visit, any changes in fasting glucose between the two visits was noted. On average, these participants were then followed for up to eight years. Data on the number of heart attacks, strokes, and all-cause mortality were collected.

Researchers discovered that those participants who shifted from the normal fasting glucose group into diabetes (glucose >126 mg/dL) were associated with a much higher risk of stroke and all-cause mortality, compared to the participants who remained in the normal glucose group. In addition, those participants initially diagnosed with impaired fasting glucose who later moved into diabetes had a much higher risk of heart attack and all-cause mortality.

The statistics for diabetes are a cause for alarm- it is estimated that the total cost for diabetes in 2017 was $327 billion. About 84 million Americans are currently in the pre-diabetic category, with one of three adults age twenty and older now being pre-diabetic. Given the results of this very robust study, with over two million person-years of follow-up, serious consideration should be given to those interventions which help those who currently have normal or impaired glucose levels from progressing into diabetes.

“No one had ever told me junk food was bad for me. Four years of medical school, and four years of internship and residency, and I never thought anything was wrong with eating sweet rolls and doughnuts, and potatoes, and breads, and sweets.”– Robert Atkins

(Source- Cardiovascular Diabetology (2018) 17:51)

This blog is a review of published medical and scientific literature, and should only be used for informational purposes. It does not constitute medical or health advice, nor does it create a physician-patient relationship with anyone. Discuss any health concerns with your personal physician.