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Whole Grains & Polyunsaturated Fats Linked with Less Heart Disease

To see how various fat sources relate to heart disease, Harvard researchers analyzed the fat intake and health outcomes of more than 222,000 people across 3 large cohorts. They found that while dairy fat intake in itself was not significantly related to heart disease risk, replacing 5% of calories from dairy fat with whole grains, polyunsaturated fat (found in fish, nuts, and seeds) or vegetable fat was linked with a 28%, 24% and 10% lower risk of heart disease, respectively. Additionally, replacing 5% of calories from other animal fats (such as red meat) with dairy fat was linked with a 6% lower risk of heart disease, indicating that while dairy fat might not be as harmful as red meat, replacing animal fats with plant foods could offer more protection. This supports the evidence that we consume and what we don’t consume both contribute to health outcomes. 
American Journal of Clinical Nutrition. 2016 Aug 24. pii: ajcn134460. [Epub ahead of print] (Chen M et al.)

Mediterranean Diet Linked with Less Plaque Build Up in Arteries

Atherosclerosis, plaque build up in the arteries, can lead to dangerous blood clots, but diet can play an important role in prevention. Researchers analyzed the eating habits and heart health markers of 4,082 adults in Spain, and identified three distinct eating patterns: the Mediterranean diet, the Western diet, and the “social-business eating pattern,” a dietary pattern with more calories, red meat, pre-made foods, alcohol, sugary drinks, snacks, and lots of eating out. Those eating a Mediterranean diet had significantly less plaque than those eating a Western or social business eating pattern, with a social-business pattern appearing to be even worse than the typical, unhealthy Western diet (characterized by not enough fruits, veggies or whole grains, and too much red meat, desserts, and sugary beverages).
Journal of the American College of Cardiology. 2016 Aug 23;68(8):805-14. 

Full Fat Mediterranean Diet Linked with Good Health

A healthy diet need not restrict fat or flavor, at least in the case of the delicious and nutritious Mediterranean diet. Researchers at the Department of Veterans Affairs in the U.S. analyzed data from 56 studies (of at least 100 people in each study) to get a big picture view of the Mediterranean diet. The studies were all controlled trials (one of the strongest types of nutrition studies) and were included so long as the participants followed at least 2 of the 7 characteristics of a Mediterranean diet (such as lots of fruits and vegetables, or a preference for olive oil and other unsaturated fats). The scientists found that a Mediterranean diet (with no restriction on fat) may help prevent heart disease, breast cancer, and type 2 diabetes, but they did not find a significant reduction in mortality.
Annals of Internal Medicine. 2016 Jul 19. (Bloomfield HE et al.) [Epub ahead of print]

Whole Grains Linked with Longevity

In a meta analysis, Harvard scientists analyzed the whole grain intake and rates of death for 786,076 adults across 14 studies. Compared to people who ate the least whole grains, people who ate the most whole grains had a 16% lower risk of death from all causes, an 18% lower risk of death from heart disease, and a 12% lower risk of death from cancer. However, the significantly lower risk of cancer death was only seen in people who ate at least 30g whole grains per day (the amount in about ½ cup cooked brown rice, or 2 slices of 100% whole grain bread). The researchers also observed a dose response relationship, meaning the more whole grains someone ate, the less likely they were to die during the study period. According to the scientists, these results “strongly supported the current Dietary Guidelines for Americans,” which encourage at least 3 servings of whole grains per day (totaling at least 48g whole grains).
Circulation. 2016 Jun 14;133(24):2370-80. (Zong G et al.)

Whole Grains Linked with Lower Risk of Heart Disease, Cancer, Respiratory Disease, Infectious Diseases, Diabetes, and Early Death

Researchers in Europe and the US analyzed 45 studies (ranging from 245,012 to 705,253 participants each) in a meta analysis to understand the relationship between whole grains and health. Compared to people who ate the least whole grains, people who ate the most whole grains had a 16-21% lower risk of heart disease, an 11% lower risk of cancer, and an 18% lower risk of death from all causes, as well as a 19% lower risk of death from respiratory disease, a 36% lower risk of death from diabetes, a 20% lower risk of death from infectious disease, and a 21% lower risk of death from all non-cardiovascular, non-cancer causes. The researchers also found that a 90g increase in whole grain foods per day (about 3 servings) was linked with a 19-22% lower risk of heart disease, a 15% lower risk of cancer, and a 17% lower risk of death from all causes, and that “even moderate increases in whole grain intake could reduce the risk of premature mortality.” Whole grain bread, whole grain cereals, total grains, total cereals, total bread, pasta, and bran, were also singled out for their relationship with lower rates of various diseases and/or early death. The researchers conclude that their findings “strongly support existing dietary recommendations to increase whole grain consumption in the general population.”
British Medical Journal. 2016 June 14;353. (Aune D et al.)

Fiber is Key for a Healthy Gut Microbiome

The gut microbiome is a fascinating new area of research, with implications in the prevention of many chronic diseases. To see how diet might play a role, researchers at the University of Alberta in Canada analyzed data on microbiome depletion. They found that dietary fiber is “the only factor that has been empirically shown to be important” to a healthy, diverse microbiome, but that unfortunately, most people do not eat enough fiber to meet the daily recommendation (which is 25-38g per day for most adults in the US). Fiber rich foods include many whole grains, vegetables, fruits, pulses, nuts, and seeds.
Trends in Endocrinology & Metabolism. 2016 May;27(5):239-42. (Deehan EC et al.)

Whole Grain Bread, Fiber, Fruit May Contribute to Healthy Gut Microbiome Diversity

While there is still much to learn about the gut microbiome, what we do know is that certain microbes appear to be more beneficial than others, and that a large diversity of different microbes seems to be protective. To figure out what constitutes a “normal” gut microbiome, European researchers combined microbiome data from nearly 4,000 people across the US and Western Europe. The researchers found that even within this large sample size, they have not yet uncovered the total richness of gut diversity. The scientists also analyzed a number of lifestyle and health factors to see if they might affect microbiome composition. After medication use and stool consistency, dietary factors (preference for whole grain bread, high fiber intake, and high fruit intake) were pinpointed as probable contributors of healthy gut diversity. 
Science. 2016 Apr 29;352(6285):560-4. (Falony G et al.)

Mediterranean Diet May Help Prevent Heart Disease

Researchers analyzed the diets of more than 15,000 adults at risk of heart disease from 39 countries to see if their eating habits were more representative of the Mediterranean diet or the Western diet. In those most closely following a Mediterranean diet, each 1 point increase on the Mediterranean Diet Score was linked with a 7% lower risk of a major heart problem (heart attack, stroke, or death) over the 4 year follow up. Similarly, researchers also calculated a simplified Mediterranean Diet Score for the participants (based only on daily consumption of fruits and vegetables, and weekly consumption of fish and alcohol), and found that each 1 point increase in the simplified Mediterranean Diet Score was linked with a 10% lower risk of major heart problems. Fish and tofu/soybeans were the only individual food groups that were significantly associated with a lower risk of heart problems after adjusting for education, health, and lifestyle factors. Consumption of specific foods common to the Western diet was not significantly linked with heart disease risk in this analysis, leading the scientists to conclude that “Greater consumption of healthy foods may be more important for secondary prevention of coronary artery disease than avoidance of less healthy foods.”
European Heart Journal. 2016 April 24. [Epub ahead of print.] (Stewart RAH et al.)

Eating Fresh Fruit Linked with Lower Blood Pressure and Blood Sugar Levels, and Lower Risk of Heart Disease

New research suggests that the old adage rings true: An apple a day may in fact keep the doctor away. In a study of more than 450,000 Chinese adults, people who ate fresh fruit daily had a 34% lower risk of heart attack, a 25-36% lower risk of stroke, and a 40% lower risk of death from heart disease than those who never or rarely ate fresh fruit (less than once per month). Additionally, the systolic blood pressure (the top number in the blood pressure reading) of the daily fresh fruit eaters was 4 mm Hg lower than that of the people who never or rarely ate fresh fruit. The researchers report that “There was a strong log-linear dose-response relationship between the incidence of each outcome and the amount of fresh fruit consumed,” meaning that the more fresh fruit someone ate, the less likely they were to have heart disease.
New England Journal of Medicine. 2016 Apr 7;374(14):1332-43. (Du H et al.)

5 Years of Healthy Lifestyle Advice Can Have Lifelong Benefits

Even a few years of healthy lifestyle advice can leave a lasting impression on long-term health. European researchers randomly assigned a large group of middle-aged Norwegian men (who were healthy, but at high risk of heart disease) to either a 5-year program with healthy lifestyle advice (specifically, advice to stop smoking, eat less saturated fat, and eat more fish and vegetables), or a control group without the advice. The researchers then followed over 1,200 of these men for 40 years, to monitor any lasting effects on mortality. The scientists conclude that “Receiving advice about a healthy lifestyle led to a long-term reduced risk of coronary mortality during the following 40 years,” and they suggest that “systematically providing effective counselling for a healthy lifestyle for 5 years can lead to lifelong benefits.”
Journal of Internal Medicine. 2016 Feb 29. [Epub ahead of print] (Holme I et al.)

Processed Barley & Oats Linked with Less Gut Microbiota Diversity

A healthy diversity of gut microbiota is associated with numerous health benefits. To see how processing grains relates to the microbiome in animals, researchers analyzed the gut microbiota of pigs after feeding them whole grain barley and oats, or extruded whole grain barley and extruded oats. Extrusion is a process used to make pasta, cereal, croutons, and other grain products, by sending a flour and water mixture through a die to get uniform shapes. The gut microbiota of pigs eating the extruded grains showed less diversity and less presence of the microbes associated with health. The researchers concluded that “cereal extrusion affects the microbiota composition and diversity towards a state generally thought to be less beneficial for health.”
Food & Function. 2016 Feb;7(2):1024-32. (Moen B et al.)

Consuming Fat from Plant Oils May Help Prevent Cardiac Death

In a large study, researchers from the Global Burden of Diseases Nutrition and Chronic Diseases Expert Group analyzed the fat consumption and coronary heart disease statistics of 186 nations across the world. They found that 10.3% of coronary heart disease deaths were attributable to not eating enough n-6 polyunsaturated fats (found in soy, walnuts, sunflower seeds, and some plant oils), while 7.7% were due to eating too much trans fat (found in margarine and highly processed foods), and 3.6% were due to eating too much saturated fat (found in red meat and butter). In 80% of nations studied, deaths from heart disease due to inadequate n-6 polyunsaturated fats was at least double the heart disease deaths due to too much saturated fat. This suggests that positive messages focused on adding in healthy foods (such as cooking vegetables in plant oils, and sprinkling nuts and seeds on meals) can have an important impact on public health.
Journal of the American Heart Association. 2016 Jan 20;5(1). Pii: e002891. (Wang Q et al.) 

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