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Category: cardiovascular health

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Published on 1 Comment on Some More Benefits of Eating Chocolate

Image result for dark chocolate Great news for chocolate lovers! A review of 19 good studies (studies with people randomly assigned to different conditions) found that chocolate (whether from cocoa products, chocolate, or cocoa beverages), overall had beneficial effects on cardiometabolic health, and that it may improve lipid metabolism, and reduce inflammation and insulin resistance. This held for both men and women. The main assumption is that it is the flavanols in chocolate that has the beneficial effects on health.

From Medical Xpress: Cocoa compound linked to some cardiovascular biomarker improvements

To the tantalizing delight of chocolate lovers everywhere, a number of recent studies employing various methods have suggested that compounds in cocoa called flavanols could benefit cardiovascular health. Now a systematic review and meta-analysis of 19 randomized controlled trials (RCTs) of cocoa consumption reveals some further pieces of supporting evidence..... "We found that cocoa flavanol intake may reduce dyslipidemia (elevated triglycerides), insulin resistance and systemic inflammation, which are all major subclinical risk factors for cardiometabolic diseases."

Liu noted some limitations in the trials. All studies were small and of short duration, not all of the biomarkers tracked in these studies changed for the better, and none of the studies were designed to test directly whether cocoa flavanol consumption leads to reduced cases of heart attacks or type 2 diabetes. But taking into account some of these heterogeneities across studies, the team's meta-analysis summarizing data from 19 trials found potential beneficial effects of flavanol-rich cocoa on cardiometabolic health. There were small-to-modest but statistically significant improvements among those who ate flavanol-rich cocoa product vs. those who did not.

The greatest effects were seen among trial volunteers who ate between 200 and 600 milligrams of flavanols a day (based on their cocoa consumption). They saw significant declines in blood glucose and insulin, as well as another indicator of insulin resistance called HOMA-IR. They also saw an increase in HDL, or "good," cholesterol. Those consuming higher doses saw some of the insulin resistance benefits and a drop in triglycerides, but not a significant increase in HDL. Those with lower doses of flavanols only saw a significant HDL benefit. 

In general, Lin said, where there were benefits they were evident for both women and men and didn't depend on what physical form the flavanol-rich cocoa product was consumed in —dark chocolate vs. a beverage, for example.

Published on Leave a comment on Eat Calcium Rich Foods, Not A Supplement

Image result for calcium rich foods, wikipedia Once again, research shows that a supplement is not beneficial and may have some health harms, while eating foods rich in the mineral or vitamin being measured has health benefits. A ten year study found that calcium supplements are not beneficial and linked to health harm - they raised the risk of atherosclerosis, as measured by "coronary artery calcification" or plaque buildup in arteries, while a diet high in calcium rich foods was linked with health benefits (a protective effect). Other studies have found a higher risk for other health problems with calcium supplements (heart attacks, kidney stones, death),

Currently an estimated 43 percent of American adults take a supplement that includes calcium. Instead, for health benefits, focus on eating calcium rich foods. Some calcium rich foods are: dairy products (milk, cheese, yogurt, kefir), sardines, salmon, broccoli, collard greens, kale, edamame, figs, oranges, white beans, okra, tofu, and almonds. From Science Daily:

Calcium supplements may damage the heart

After analyzing 10 years of medical tests on more than 2,700 people in a federally funded heart disease study, researchers at Johns Hopkins Medicine and elsewhere conclude that taking calcium in the form of supplements may raise the risk of plaque buildup in arteries and heart damage, although a diet high in calcium-rich foods appears be protective.

In a report on the research....the researchers caution that their work only documents an association between calcium supplements and atherosclerosis, and does not prove cause and effect. But they say the results add to growing scientific concerns about the potential harms of supplements....But our study adds to the body of evidence that excess calcium in the form of supplements may harm the heart and vascular system.

"The researchers were motivated to look at the effects of calcium on the heart and vascular system because studies already showed that "ingested calcium supplements -- particularly in older people -- don't make it to the skeleton or get completely excreted in the urine, so they must be accumulating in the body's soft tissues," says nutritionist John Anderson, Ph.D., professor emeritus of nutrition at the University of North Carolina at Chapel Hill's Gillings School of Global Public Health and a co-author of the report. Scientists also knew that as a person ages, calcium-based plaque builds up in the body's main blood vessel, the aorta and other arteries, impeding blood flow and increasing the risk of heart attack.

Their study focused on 2,742 of these participants who completed dietary questionnaires and two CT scans spanning 10 years apart. The participants chosen for this study ranged in age from 45 to 84, and 51 percent were female. Forty-one percent were white, 26 percent were African-American, 22 percent were Hispanic and 12 percent were Chinese. At the study's onset in 2000, all participants answered a 120-part questionnaire about their dietary habits to determine how much calcium they took in by eating dairy products; leafy greens; calcium-enriched foods, like cereals; and other calcium-rich foods....The coronary artery calcium tests were repeated 10 years later to assess newly developing or worsening coronary heart disease.

Next, the investigators focused on the differences among those taking in only dietary calcium and those using calcium supplements. Forty-six percent of their study population used calcium supplements. The researchers.....found that supplement users showed a 22 percent increased likelihood of having their coronary artery calcium scores rise higher than zero over the decade, indicating development of heart disease....Among participants with highest dietary intake of calcium -- over 1,022 milligrams per day -- there was no increase in relative risk of developing heart disease over the 10-year study period.

Excerpts from the original study (Please note:  CVD = cardiovascular disease, CAC = coronary artery calcification) in the  Journal of the American Heart Association:  Calcium Intake From Diet and Supplements and the Risk of Coronary Artery Calcification and its Progression Among Older Adults: 10‐Year Follow‐up of the Multi‐Ethnic Study of Atherosclerosis (MESA)

Recent evidence derived from randomized, controlled trials, including the Women's Health Initiative, have raised a concern for an association between calcium supplement use and increased risk for CVD events.12, 13, 14 Among calcium supplement users, a high intake of calcium greater than 1400 mg/day has been reported to be associated with higher death rates from all causes, including from CVD.15

The purported CVD risk associated with total calcium intake may depend on the source of calcium intake.3 Intake of calcium from food sources has not been shown to increase CVD risk, whereas a signal for increased risk of myocardial infarction (MI) among calcium supplement users has been reported.7 In a similar fashion, dietary calcium intake may decrease risk of kidney stones, whereas calcium supplementation may increase risk.16 One explanation for this apparent paradox may be that large boluses of calcium intake through supplements may transiently elevate serum calcium concentrations,17, 18 which, in turn, may lead to vascular calcification and other adverse health effects.

In summary, results from this long‐term study of 10 years showed a protective relationship between total calcium intake and incident coronary atherosclerosis, particularly among nonsupplement users. Even though mean total calcium intake in quintile 5 was greater than the upper limits of current recommendations, no increased risk of CAC progression was found, and the highest quintile of calcium intake actually had decreased risk of incident CAC among those without prevalent CAC at baseline. However, we found evidence that calcium supplement use was independently associated with incident CAC, whether or not we adjusted for total calcium intake.

Published on Leave a comment on Time For Doctors To Prescribe Exercise

We all know that exercise is beneficial for health. Research suggests that exercising out in nature is best for several varied reasons -  including that it lowers markers of inflammation, and that it's good for our gut microbiome (community of gut microbes). The following excerpts are written by Dr. John La Puma encouraging other doctors to prescribe exercise for their patients and why.

An important message of his is that exercise is more important than a drug prescription for a number of conditions, including diabetes prevention, reducing the risk of recurrence of several cancers (he mentions breast cancer, but it also holds for prostate cancer). While exercising and walking out in nature may be best, any exercise anywhere is better than no exercise. (Other posts on exercise as prescription medicine are here and here; and check the category exercise for all exercise research posts).

From Medscape: Rx: Exercise Daily -- Outdoors. Doctor's Orders

With dazzling Olympic feats on display all summer, too many of my patients are still literally immobilized. Medically, sitting too long shuts off the enzyme lipoprotein lipase. In people who are sedentary, the enzyme doesn't break down fat to create energy, like it should. But medical prescription for exercise has lagged even the slowest runner. Why? Some reasons are time, training, and money. Time especially is a scarce commodity: The average clinician visit lasts just 20 minutes. Fitness is a shamefully small part of medical training. And as doctors, we don't get paid for discussing exercise, let alone monitoring a prescription and assessing the response. 

Finally, there are practical reasons. Clinicians find it difficult to persuade patients that exercise is more effective than medication for any number of conditions, including stroke recovery, diabetes prevention, and treatment of low back pain. Regular exercise reduces the risk for recurrent breast cancer by approximately 50%. Given all these reasons, it's easy to see why fitness prescriptions are seldom more than an afterthought. Yet even without formally prescribing the frequency, intensity, time, and type of exercise, clinicians can speak with patients and families about fitness in inspiring, life-changing ways.

Because clinicians have a secret weapon to use that most people don't even know about—location. Exercising in nature (in sight of and preferably near water or greenery, whether a deserted beach or an urban park) is better. Walking city streets and the office itself can be harder on your health than you think. In both environments, your attention is demanded and directed—sometimes by digital interruptions, sometimes by vehicles, toxins, or duties. In nature, your attention is drawn, not pushed, to a variety of often unexpected but not unpleasant sounds, colors, aromas, textures, and forms.

A recent Stanford study of nature therapy showed significantly reduced rumination after a 90-minute walk in nature, compared with a 90-minute walk through an urban environment. On MRI, "nature walkers" showed lower activity in an area of the brain linked to risk for mental illness, the subgenual prefrontal cortex, compared with "urban walkers." In other words, nature offers a sense of something bigger than ourselves on which to focus. MRIs show the way the brain changes when that sense occurs to us.

Exercising in nature may improve a person's immune system by enriching the diversity in the microbiota. Microbiota buffer the immune system against chronic stress-related disease. They appear to act as a hormone-producing organ, not simply a collection of beneficial bacteria. Microbiota are sensitive and responsive to physical environmental changes as well as dietary ones. So, exercise in nature may favorably boost microbiota.

And finally, exercise in nature is clinically preferred and calming. A Norwegian study showed that exercise in nature and in view of nature improves both mood and diastolic blood pressure vs exercise without nature. A Chinese study showed higher energy levels, and lower levels of interleukin-6 and tumor necrosis factor (both markers of inflammation), in a forest walking group compared with an urban exercising group. A British study showed significantly improved mood and self-esteem with "green" exercise, with the largest benefits from 5-minute engagements. Five minutes!

Of course, there are areas in our country and world in which it is dangerous to walk, never mind exercise. It may not be as easy to generate sweat and intensity with outdoor exercise as it is with indoor exercise. It may be stormy, or baking hot, or otherwise harsh outside, and the cool recesses of one's own bedroom or the gym may be just perfect for you today. And with the 2013 total cost of inactivity estimated at $24.7 billion for the United States, and with the public sector bearing almost one half of that expense, any exercise anywhere is better than none.  Yet physicians have a therapeutic tool few others in our culture wield—a prescription pad—and we have every patient's attention, at least for a few minutes. Patients try harder when doctors advise them about fitness. 

Published on Leave a comment on Exercise Can Lead To Misdiagnosis of Heart Disease

 The last post pointed out that the importance of high levels of physical activity or exercise in reducing the risk of 5 diseases. Now a study points out that all this exercise (starting at about 3 to 5 hours of exercise per week) can result in the heart becoming enlarged from all this exercise ("athlete's heart"), and that this is totally normal and healthy. The researchers also stressed that doctors should be aware that athlete's heart or "exercise-related cardiac remodeling" can occur not only in professional athletes, but also in those engaging in moderate levels of exercise, and that it not be misdiagnosed as heart disease. From Science Daily:

Regular exercise can lead to heart disease misdiagnosis

Scientists have shown that people who exercise for even a few hours each week can enlarge their hearts. This is a normal and beneficial response to exercise, but until now has only been recognised in athletes. The researchers say that doctors should now consider an individual's activity level before diagnosing common heart conditions.

"It's well known that the hearts of endurance athletes adapt in response to exercise, a phenomenon called 'athlete's heart'. This study is the first to show that healthy adults who do regular exercise may also develop enlarged hearts. As a result, there's a risk that some active adults could be misdiagnosed with heart disease," says Declan O'Regan, of the MRC Clinical Sciences Centre, based at Imperial College London, and one of the lead scientists on the research. The findings were published today in Circulation: Cardiovascular Imaging.

Scientists have not previously known the extent to which the hearts of healthy people adapt to the demands of moderate exercise. Over 1000 people took part in this study, making it one of the largest of its kind. Participants selected one of four possible categories that best represented their activity level over the past year, according to how many hours of exercise they did each week. Around one third of participants reported doing three to five hours of exercise, and the scientists found that one in five of these people had developed an enlarged heart as a result. Similar adaptations were seen in almost half of those who reported doing more than five hours of exercise.

The findings suggest that above a threshold of three hours, the more exercise you do, the more your heart is likely to adapt, and the more the exercise, the more pronounced the changes. "Going to the gym frequently increases the thickness of your heart muscle and the volume of your heart chambers, particularly the right ventricle. It's a completely normal, healthy response. It shouldn't be misdiagnosed as being heart disease," says O'Regan. These adaptations allow the heart to pump more blood, which helps to supply exercising muscles with the oxygen and nutrients they need. Changes to the heart's thickness and volume happen in tandem, and this distinguishes them from the changes seen in disease, which occur in isolation.

Today, doctors across the world use a standard of set values to see if the thickness and volume of a person's heart fall into the healthy or abnormal range. This helps to ensure consistency between different hospitals. According to O'Regan, the data that underpins these ranges comes from a relatively small study with people who were mainly sedentary. He says, "In this latest study, we looked at a much larger and broader group of people. We found that more people reported being active than had done in previous studies. Our recommendations reflect this growing participation in exercise.".....And this interesting research shows that even moderate physical activity is associated with changes in the heart's size and shape, which are visible on a cardiac MRI.

Published on Leave a comment on Really Increase Activity Level to Reduce Risk of 5 Diseases

Get active, really active, to reduce your risk for 5 diseases: breast cancer, colon cancer, heart disease, and ischemic stroke. Instead of the 150 minutes of brisk walking or 75 minutes per week of running (which is equal to the 600 metabolic equivalent (MET) minutes now recommended by the World Health Organization), this study found that much more exercise is needed for best health results.

This study (which was a review and analysis of 174 studies) found that there is a dose-response effect, with the most reduction in the risk of the 5 conditions by getting 3000 to 4000 MET minutes per week. This sounds like a lot, but the researchers  point out that this can be achieved by incorporating exercise into your daily routines. The researchers write: "A person can achieve 3000 MET minutes/week by incorporating different types of physical activity into the daily routine—for example, climbing stairs 10 minutes, vacuuming 15 minutes, gardening 20 minutes, running 20 minutes, and walking or cycling for transportation 25 minutes on a daily basis would together achieve about 3000 MET minutes a week."

So start thinking creatively about how to increase exercise or activity into your daily life, especially moderate or vigorous intensity activity. For example, park your car far from the store door, or better yet, bicycle or walk to the store from home. From Medscape:

Get Moving: High Physical-Activity Level Reduces Risk of 5 Diseases

High levels of physical activity can reduce the risk for five major diseases, including type 2 diabetes, new research shows. Findings from the systematic review and meta-analysis were published online ....The data, from a total 174 studies comprising 149,184,285 total person-years of follow-up, suggest that the more total regular daily physical activity one engages in — including recreation, transportation, occupational activity, and/or daily chores — the lower the risks for breast cancer, colon cancer, diabetes, ischemic heart disease, and ischemic stroke.

However, significant reductions in those conditions were seen only with total activity levels considerably higher than the minimum 600 metabolic equivalent (MET) minutes per week recommended by the World Health Organization for health benefits. That 600 METs equates to about 150 minutes/week of brisk walking or 75 minutes/week of running. (A MET is defined as the ratio of the metabolic rate during that activity to the metabolic rate when resting.) Risks of the five conditions dropped significantly with an increase in MET minutes per week from 600 to 3000 to 4000, with less additive benefit seen above that level.

For reference, the authors say, "a person can achieve 3000 MET minutes/week by incorporating different types of physical activity into the daily routine — for example, climbing stairs 10 minutes, vacuuming 15 minutes, gardening 20 minutes, running 20 minutes, and walking or cycling for transportation 25 minutes on a daily basis would together achieve about 3000 MET minutes a week." "This amount might seem a bit large, but this is about total activity across all domains of life.…For people who currently don't exercise, clinicians could encourage them to incorporate physical activity into their daily routines, [such as] turning household chores into exercise. 

Another recent meta-analysis of trials involving more than one million individuals indicated that an hour of moderate-intensity activity, such as brisk walking or cycling, offsets the health risks of 8 hours of sitting. The message that physical inactivity is a killer — leading to 5.3 million premature deaths annually worldwide, which is as many as caused by smoking and twice as many as associated with obesity, has been emerging over the past few years, with warnings that "sitting is the new smoking."

This new research is the first meta-analysis to quantify the dose-response association between total physical activity across all domains and the risk of five chronic diseases. The 174 prospective cohort studies included 35 for breast cancer, 19 for colon cancer, 55 for diabetes, 43 for ischemic heart disease, and 26 for ischemic stroke. (Some included more than one end point.)....Higher levels of total physical activity were associated with lower risks of all five outcomes.

With the development of diabetes, for example, compared with no physical activity, those with 600 MET minutes per week (the minimum recommended level of activity) had a 2% lower risk. That risk reduction jumped by an additional 19% with an increase from 600 to 3600 METs/week. Gains were smaller above that, with the increase of total activity from 9000 to 12,000 MET minutes/week yielding only an additional 0.6% diabetes reduction.

Overall, compared with insufficiently active individuals (total activity < 600 MET minutes/week), the risk reduction for those in the highly active category (≥ 8000 MET minutes/week) was 14% for breast cancer; 21% for colon cancer; 28% for diabetes; 25% for ischemic heart disease; and 26% for ischemic stroke. 

Credit: Medscape

Published on Leave a comment on Twin Study Finds Being Overweight Not Linked To Early Death or Heart Attack

Another interesting study looking at whether being overweight is linked to premature death, heart attacks, and diabetes. This study looked at sets of twins, in which one is heavier than the other, and followed them long-term (average 12.4 years) and found that NO - being overweight or obese (as measured by Body Mass Index or BMI) is NOT associated with premature death or heart attack (myocardial infarction), but it is associated with higher rates of type 2 diabetes. These results are in contrast with what a large study recently found. From Science Daily:

Higher BMI not associated with increased risk of heart attack or early death, twin study shows

A study of 4,046 genetically identical twin pairs with different amounts of body fat shows that twin siblings with a higher Body Mass Index, as a measure of obesity, do not have an increased risk of heart attack or mortality. The study, conducted by researchers at Umeå University in Sweden, also shows that a higher BMI is associated with an increased risk of type 2 diabetes...."The results suggest that lifestyle changes that reduce levels of obesity do not have an effect on the risk of death and heart attack, which contradicts conventional understandings of obesity-related health risks," says Peter Nordström, researcher at the Department of Community Medicine and Rehabilitation at Umeå University.

In the cohort study, Peter Nordström and research colleagues at Umeå University compared health data from 4,046 monozygotic twin pairs. All twins in the study had different levels of body fat, as measured in BMI....During a follow-up period of on average 12.4 years, differences between the twins were compared when it comes to incidents of mortality, heart attack and type 2 diabetes. The results clearly showed that twin siblings with a higher BMI did not have an increased risk of mortality or heart attack compared to their thinner counterparts. However, twins with a higher BMI did have an increased risk of developing type 2 diabetes.

The results showed that: - Among twin siblings with a higher BMI (mean value 25.1), there were 203 heart attacks (5 %) and 550 deaths (13.6 %) during the follow-up period. - Among twin siblings with a lower BMI (mean value 23.9), there were 209 heart attacks (5.2 %) and 633 deaths (15.6 %) during the same period. - Among the 65 twin pairs in the study who had a BMI difference of 7 or higher, and where the larger twin siblings had a BMI of 30 or higher, there were still no noticeably increased risk of mortality or heart attack associated with a higher BMI.

The study, described in the article Risks of Myocardinal Infarction, Death, and Diabetes in Identical Twin Pairs With Different Body Mass Index, is based on the Swedish Twin Registry, the largest of its kind in the world. The median age of the twins in the study was 57.5 and participants' ages ranged from 42-92. The cohort study was conducted between 1998 and 2003, with follow-ups regarding incident of mortality, heart attack and diabetes during a 10 year period until 2013. One study limitation was that weight and length (used to calculate BMI) was self-reported.

Published on Leave a comment on Frequent Nut Consumption Has Health Benefits

Studies have found that increased nut consumption has been associated with reduced risk of cardiovascular disease and type 2 diabetes. A newly published study looked at large groups of people to see if this was due to nuts reducing systemic inflammation throughout the body - which can be measured by inflammatory biomarkers such as C-reactive protein (CRP) and  interleukin 6 (IL6).

The researchers found that nut consumption was inversely associated with concentrations of biomarkers CRP and IL-6 - that is, the more nuts eaten weekly, the lower the inflammatory biomarkers. They also found that substituting nuts for red meat, processed meat, eggs, refined grains, potatoes, or potato chips was associated with a healthier inflammatory biomarker profile. In the study, one serving of nuts was equivalent to 28 g (1 oz) of peanuts or other nuts. What's in nuts? Unsaturated fatty acids, high quality plant protein, fiber, minerals, vitamins, bioactive compounds such as phytosterols, antioxidants, magnesium, etc. Bottom line: eat a serving of nuts at least several times a week. From Science Daily:

Frequent nut consumption associated with less inflammation

In a study of more than 5,000 people, investigators from Brigham and Women's Hospital have found that greater intake of nuts was associated with lower levels of biomarkers of inflammation, a finding that may help explain the health benefits of nuts. The results of the study appear July 27 in the American Journal of Clinical Nutrition.

"Population studies have consistently supported a protective role of nuts against cardiometabolic disorders such as cardiovascular disease and type 2 diabetes, and we know that inflammation is a key process in the development of these diseases," said corresponding author Ying Bao, MD, ScD, an epidemiologist in BWH's Channing Division of Network Medicine. "Our new work suggests that nuts may exert their beneficial effects in part by reducing systemic inflammation."

Previously Bao and her colleagues observed an association between increased nut consumption and reduced risk of major chronic diseases and even death, but few prospective cohort studies had examined the link between nut intake and inflammation. In the current study, the research team performed a cross-sectional analysis of data from the Nurses' Health Study, which includes more than 120,000 female registered nurses, and from the Health Professionals Follow-Up Study, which includes more than 50,000 male health professionals.... looked at the levels of certain telltale proteins known as biomarkers in blood samples collected from the study participants. They measured three well-established biomarkers of inflammation: C-reactive protein (CRP), interleukin 6 (IL6) and tumor necrosis factor receptor 2 (TNFR2).

After adjusting for age, medical history, lifestyle and other variables, they found that participants who had consumed five or more servings of nuts per week had lower levels of CRP and IL6 than those who never or almost never ate nuts. In addition, people who substituted three servings per week of nuts in place of red meat, processed meat, eggs or refined grains had significantly lower levels of CRP and IL6.

Peanuts and tree nuts contain a number of healthful components including magnesium, fiber, L-arginine, antioxidants and unsaturated fatty acids such as α-linolenic acid. Researchers have not yet determined which of these components, or if the combination of all of them, may offer protection against inflammation, but Bao and her colleagues are interested in exploring this further through clinical trials that would regulate and monitor diet.

Published on

Yup, according to a new mega-study, being overweight or obese is linked to higher risk of dying prematurely than being normal weight.  And the more you weigh, the greater the risk. This mega-study that looked at data from many studies and countries, also found that being underweight is linked to a higher risk of premature death. What's the best weight to be? A BMI of 22.5-<25 kg/m2 is considered a healthy weight range, and had the lowest mortality risk in the study. Being overweight was linked to higher rates of death from "all causes", and also from 4 major causes: coronary heart disease, stroke, respiratory disease, and cancer.

However, note that while other studies also agree that being underweight or obese increases the rate of dying prematurely, there is still some debate over whether being just overweight with BMI 25–<30 kg/m2 , really has a higher risk of dying prematurely. This was pointed out in the accompanying editorial in the journal Lancet (but not mentioned below). From Science Daily:

As overweight and obesity increase, so does risk of dying prematurely: Major study

Being overweight or obese is associated with a higher risk of dying prematurely than being normal weight -- and the risk increases with additional pounds, according to a large international collaborative study led by researchers at the Harvard T.H. Chan School of Public Health and the University of Cambridge, UK. The findings contradict recent reports that suggest a survival advantage to being overweight -- the so-called "obesity paradox."

The deleterious effects of excess body weight on chronic disease have been well documented. Recent studies suggesting otherwise have resulted in confusion among the public about what is a healthy weight. According to the authors of the new study, those prior studies had serious methodological limitations. One common problem is called reverse causation, in which a low body weight is the result of underlying or preclinical illness rather than the cause. Another problem is confounding by smoking because smokers tend to weigh less than nonsmokers but have much higher mortality rates.....Hu stressed that doctors should continue to counsel patients regarding the deleterious effects of excess body weight, which include a higher risk of diabetes, cardiovascular disease, and cancer.

For the new study, consortium researchers looked at data from more than 10.6 million participants from 239 large studies, conducted between 1970 and 2015, in 32 countries. A combined 1.6 million deaths were recorded across these studies, in which participants were followed for an average of 14 years. For the primary analyses, to address potential biases caused by smoking and preexisting diseases, the researchers excluded participants who were current or former smokers, those who had chronic diseases at the beginning of the study, and any who died in the first five years of follow-up, so that the group they analyzed included 4 million adults. They looked at participants' body mass index (BMI) -- an indicator of body fat calculated by dividing a person's weight in kilograms by their height in meters squared (kg/m2).

The results showed that participants with BMI of 22.5-<25 kg/m2 (considered a healthy weight range) had the lowest mortality risk during the time they were followed. The risk of mortality increased significantly throughout the overweight range: a BMI of 25-<27.5 kg/m2 was associated with a 7% higher risk of mortality; a BMI of 27.5-<30 kg/m2 was associated with a 20% higher risk; a BMI of 30.0-<35.0 kg/m2 was associated with a 45% higher risk; a BMI of 35.0-<40.0 kg/m2 was associated with a 94% higher risk; and a BMI of 40.0-<60.0 kg/m2 was associated with a nearly three-fold risk. Every 5 units higher BMI above 25 kg/m2 was associated with about 31% higher risk of premature death. Participants who were underweight also had a higher mortality risk.

Looking at specific causes of death, the study found that, for each 5-unit increase in BMI above 25 kg/m2, the corresponding increases in risk were 49% for cardiovascular mortality, 38% for respiratory disease mortality, and 19% for cancer mortality. Researchers also found that the hazards of excess body weight were greater in younger than in older people and in men than in women.

Published on Leave a comment on Omega-3s and Heart Disease

Previous research on the health benefits of eating fish, fish oil supplements, and other sources of omega-3 fatty acids has shown mixed results, with some studies revealing cardiac health benefits and others finding no benefit. However, when looking at recent studies separating eating foods rich in omega-3 fatty acids versus taking supplements, it appears that eating foods has various beneficial health effects, while taking a supplement may not find health benefits (here and here).

The latest research (reported in the journal JAMA Internal Medicine) looked at heart disease events (heart attack, cardiac related death) and actually measured the actual levels of omega-3 fatty acids in the participants' blood, as opposed to relying on questionnaires in which people report what they eat. The new study could not assess the usefulness of taking fish oil supplements, as opposed to eating fish, because so few people in the study took supplements. Thus the findings were generally from eating a diet rich in omega-3s from either fish or plant-based sources. (Note: By far the best source is fish. Some plant-based sources are: flaxseed, walnuts, edamame, black beans, kidney beans).

The new study — which combined 19 studies from 16 countries with more than 45,000 participants — found that higher circulating blood levels of omega-3 fatty acids were associated with a nearly 10 percent lower risk of a fatal heart attack, on average, compared with lower levels. The participants with the highest level of omega-3s in their blood had the greatest risk reduction — a more than 25 percent lower risk of having a fatal heart attack, the study found.

From Science Daily: Consumption of omega-3s linked to lower risk of fatal heart disease

A global consortium of researchers banded together to conduct an epidemiological study analyzing specific omega-3 fatty acid biomarkers and heart disease. They found that blood levels of omega-3 fatty acids from seafood and plant-based foods are associated with a lower risk of fatal heart attack.

A total of 19 studies were involved from 16 countries and including 45,637 participants. Of these, 7,973 people developed a first heart attack over time, including 2,781 deaths and 7,157 nonfatal heart attacks.

Overall, both plant-based and seafood-based omega-3s were associated with about a 10 percent lower risk of fatal heart attacks. In contrast, these fatty acids biomarkers were generally not associated with a risk of nonfatal heart attacks, suggesting a more specific mechanism for benefits of omega-3s related to death."At a time when some but not other trials of fish oil supplementation have shown benefits, there is uncertainty about cardiovascular effects of omega-3s," said Mozaffarian. "Our results lend support to the importance of fish and omega-3 consumption as part of a healthy diet."

Fish is the major food source of omega-3 fatty acids, including eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA). According to the U.S. Department of Agriculture's National Nutrient Database, fatty fish such as salmon, trout, anchovies, sardines, and herring contain the highest amounts of omega-3 fatty acids, although all fish contain some levels. In addition to omega-3 fatty acids, fish provide specific proteins, vitamin D, selenium, and other minerals and elements. Alpha-linolenic acid (ALA) is the plant-based omega-3 fatty acid found in walnuts, flaxseed oil, and canola oil and some other seed and nuts and their oils.

Published on Leave a comment on Eating Whole Grains Linked To Living Longer

A second study was just published about the benefits of eating whole grains daily - again a significantly lower risk of premature death, and again the effects were dose-related. That is, the more whole grains eaten daily, the lower the risk of early death. Like the first study, this also was a review study. This study (published in BMJ) found that whole grain consumption was associated with a reduction in the risk for death from cancer, coronary heart disease (heart attack and stroke), respiratory disease, infectious disease, and diabetes.

A slice of 100 percent whole grain bread contains about 16 grams of whole grains, and current U.S. dietary guidelines recommend 48 grams or more of whole grains daily, but this study suggests that eating even more whole grains daily is best (eating 90 grams of whole grains a day reduced the risk for mortality from all causes by 17 percent).

Grains are divided into two subgroups: whole grains and refined grains. Whole grains or foods made from them contain all the essential parts and naturally-occurring nutrients of the entire grain seed in their original proportions. This definition means that 100% of the original kernel – all of the bran, germ, and endosperm – must be present to qualify as a whole grain. Some whole grains are: whole wheat. barley. buckwheat, corn (including whole cornmeal and popcorn), millet, oats (including oatmeal), quinoa, brown rice, rye, sorghum, spelt, bulgur, and wild rice. From Eurekalert:

Seven servings of whole grains a day keep the doctor away

Eating three more portions of dietary fiber a day--say, two pieces of whole grain bread and a bowl of whole grain breakfast cereal--is associated with a lower risk for all cardiovascular diseases and for dying of cancer, diabetes, and respiratory and infectious diseases, a study just published in the BMJ has shown. The study is strong proof that consuming lots of whole grains is good for our health, says first author Dagfinn Aune, a PhD candidate at the Norwegian University of Science and Technology who is currently working at Imperial College, London.

....In general, the study showed that the higher the consumption, the better protected you are. "We saw the lowest risk among people who ate between seven and seven and a half servings of whole grain products a day, which was the highest intake across all the studies. This corresponds to 210-225 grams of whole grain products in fresh weight and about 70-75 grams of whole grains in dry weight, and is about the same as the health authorities in Norway and other Nordic countries recommend as the minimum daily allowance," says Aune.

The researchers' analyses showed fewer risk factors for people who consumed more bread and cereal with whole grains, as well as foods with added bran. On the other hand, people who ate a lot of white bread, rice or cereals with refined grains did not show reduced risk.

Nine studies with a total of more than 700,000 participants examined the risk for all types of cardiovascular disease and correlated cardiovascular deaths....The risk of dying prematurely from all causes was 18% lower for individuals who consumed a lot of whole grains compared to those who consumed lesser amounts, while three additional servings each day were associated with a 17% reduction in mortality. The risk for deaths associated with cancer (15%), respiratory diseases (22%), diabetes (51%) and infectious diseases (26%) was also lower the more whole grains individuals consumed.