What's with the blueberry obsession in medical studies? Another study finding health benefits with frequent eating of blueberries was recently published in the American Journal of Clinical Nutrition. Researchers at the Univ. of Anglia in the United Kingdom found that eating one cup of blueberries daily for 6 months reduced risk factors for cardiovascular disease (e.g. improvements in endothelial function, systemic arterial stiffness, and HDL cholesterol concentrations). They predicted that this would result in 12 to 15% reductions in heart (cardiovascular) disease risk.
The nicely done study was conducted on 138 overweight or obese men aged 50 to 75 years, all with Metabolic syndrome (e.g. hypertension, low levels of HDL cholesterol, impaired fasting glucose) - thus a group at risk for heart disease. Interestingly, ingesting 1/2 cup of blueberries a day did not have health benefits - only 1 cup of blueberries a day did. So it was dose dependent -the more, the better. However, the study did not find any improvements in blood pressure or insulin resistance (glucose control) at the end of 6 months.
Remember, one should not focus on individual foods (e.g. blueberries), but should strive for a good dietary pattern, such as the Mediterranean diet. That means a diet rich in fruits and vegetables, whole grains, seeds, nuts, and legumes. These foods have lots of fiber and feed the beneficial microbes in the gut. Eating one beneficial food such as blueberries won't overcome an entire unhealthy dietary pattern, such as the Western one (lots of highly processed foods, low in fiber, lots of fast food, sugary drinks, etc).
BOTTOM LINE: While this study focused on blueberries, research shows that eating all types of berries (blueberries, blackberries, raspberries, lingonberries, bilberries, strawberries, etc.) have health benefits. One should actually try eating a variety of berries, if possible, because they all have different nutrients, microbes (to feed beneficial bacteria in the gut), and different health benefits.
From Medical Xpress: Eating blueberries every day improves heart health
Eating a cup of blueberries a day reduces risk factors for cardiovascular disease—according to new research led by the University of East Anglia, in collaboration with colleagues from Harvard and across the UK. New findings published today in the American Journal of Clinical Nutrition show that eating 150g of blueberries daily reduces the risk of cardiovascular disease by up to 15 percent.
The research team from UEA's Department of Nutrition and Preventive Medicine, Norwich Medical School, say that blueberries and other berries should be included in dietary strategies to reduce the risk of cardiovascular disease—particularly among at risk groups.
The team set out to see whether eating blueberries had any effect on Metabolic Syndrome—a condition, affecting one-third of westernised adults, which comprises at least three of the following risk factors: high blood pressure, high blood sugar, excess body fat around the waist, low levels of 'good cholesterol' and high levels of triglycerides. Lead researcher Prof Aedin Cassidy, from UEA's Norwich Medical School, said: "Having Metabolic syndrome significantly increases the risk of heart disease, stroke and diabetes and often statins and other medications are prescribed to help control this risk.
"It's widely recognized that lifestyle changes, including making simple changes to food choices, can also help. Previous studies have indicated that people who regularly eat blueberries have a reduced risk of developing conditions including type 2 diabetes and cardiovascular disease. This may be because blueberries are high in naturally occurring compounds called anthocyanins, which are the flavonoids responsible for the red and blue color in fruits.
The team investigated the effects of eating blueberries daily in 138 overweight and obese people, aged between 50 and 75, with Metabolic Syndrome. The six-month study was the longest trial of its kind. They looked at the benefits of eating 150 gram portions (one cup) compared to 75 gram portions (half a cup). The participants consumed the blueberries in freeze-dried form and a placebo group was given a purple-colored alternative made of artificial colors and flavorings.
Co-lead, Dr. Peter Curtis, also from UEA's Norwich Medical School, said: "We found that eating one cup of blueberries per day resulted in sustained improvements in vascular function and arterial stiffness—making enough of a difference to reduce the risk of cardiovascular disease by between 12 and 15 percent.
"Unexpectedly, we found no benefit of a smaller 75 gram (half cup) daily intake of blueberries in this at-risk group. It is possible that higher daily intakes may be needed for heart health benefits in obese, at-risk populations, compared with the general population."