ScienceDaily (Apr. 11, 2011) — The benefits of blueberry consumption have been demonstrated in several nutrition studies, more specifically the cardio-protective benefits derived from their high polyphenol content. Blueberries have shown potential to have a positive effect on everything from aging to metabolic syndrome. Recently, a researcher from Texas Woman’s University (TWU) in Denton, TX, examined whether blueberries could play a role in reducing one of the world’s greatest health challenges: obesity.
Shiwani Moghe, MS, a graduate student at TWU, decided to evaluate whether blueberry polyphenols play a role in adipocyte differentiation, the process in which a relatively unspecialized cell acquires specialized features of an adipocyte, an animal connective tissue cell specialized for the synthesis and storage of fat. Plant polyphenols have been shown to fight adipogenesis, which is the development of fat cells, and induce lipolysis, which is the breakdown of lipids/fat.
“I wanted to see if using blueberry polyphenols could inhibit obesity at a molecular stage,” said Moghe. The study was performed in tissue cultures taken from mice. The polyphenols showed a dose-dependent suppression of adipocyte differentiation. The lipid content in the control group was significantly higher than the content of the tissue given three doses of blueberry polyphenols. The highest dose of blueberry polyphenols yielded a 73% decrease in lipids; the lowest dose showed a 27% decrease.
“We still need to test this dose in humans, to make sure there are no adverse effects, and to see if the doses are as effective. This is a burgeoning area of research. Determining the best dose for humans will be important,” said Moghe. “The promise is there for blueberries to help reduce adipose tissue from forming in the body.”
These preliminary results contribute more items to the laundry list of benefits related to blueberries, which have already been shown to mitigate health conditions like cardiovascular disease and metabolic syndrome.
Moghe presented her research at the Experimental Biology 2011 meeting for the American Society for Nutrition on April 10.
ScienceDaily (Apr. 20, 2009) — Could eating blueberries help get rid of belly fat? And could a blueberry-enriched diet stem the conditions that lead to diabetes? A new University of Michigan Cardiovascular Center study suggests so.
The new research, presented April 19 at the Experimental Biology convention in New Orleans, gives tantalizing clues to the potential of blueberries in reducing risk factors for cardiovascular disease and metabolic syndrome. The effect is thought to be due to the high level of phytochemicals – naturally occurring antioxidants – that blueberries contain.
The study was performed in laboratory rats. While the animal findings suggest blueberries may be protective against two health conditions that affect millions of Americans, more research should be done.
The researchers studied the effect of blueberries (freeze dried blueberries crushed into a powder) that were mixed into the rat diet, as part of either a low- or high-fat diet. They performed many comparisons between the rats consuming the test diets and the control rats receiving no blueberry powder. All the rats were from a research breed that is prone to being severely overweight.
In all, after 90 days, the rats that received the blueberry-enriched powder, measured as 2 percent of their diet, had less abdominal fat, lower triglycerides, lower cholesterol, and improved fasting glucose and insulin sensitivity, which are measures of how well the body processes glucose for energy.
While regular blueberry intake reduced these risks for cardiovascular disease and metabolic syndrome, the health benefits were even better when combined with a low-fat diet.
In addition to all the other health benefits, the group that consumed a low-fat diet had lower body weight, lower total fat mass and reduced liver mass, than those who ate a high fat diet. An enlarged liver is linked to obesity and insulin resistance, a hallmark of diabetes.
The rats in the study were similar to Americans who suffer fatty liver disease and metabolic syndrome as a result of high-fat diets and obesity. Metabolic syndrome is a group of health problems that include too much fat around the waist, elevated blood pressure, elevated blood sugar, high triglycerides, and together these conditions increase the risk of heart attacks, strokes and diabetes.
But were the health benefits seen in rats a result of losing abdominal fat, or something else?
“Some measurements were changed by blueberry even if the rats were on a high fat diet,” says E. Mitchell Seymour, M.S., lead researcher and manager of the U-M Cardioprotection Research Laboratory. “We found by looking at fat muscle tissue, that blueberry intake affected genes related to fat-burning and storage. Looking at muscle tissue, we saw altered genes related to glucose uptake.”
Steven Bolling, M.D., a U-M heart surgeon and head of the Cardioprotection Laboratory, says: “The benefits of eating fruits and vegetables has been well-researched, but our findings in regard to blueberries shows the naturally occurring chemicals they contain, such as anthocyanins, show promise in mitigating these health conditions.”
Although the current study was supported by the U.S. Highbush Blueberry Council, which also supplied the blueberry powder, the council did not play a role in the study’s conduct, analysis or the preparation of the poster presentation.
ScienceDaily (Jan. 15, 2011) — Eating blueberries can guard against high blood pressure, according to new research by the University of East Anglia (UEA) and Harvard University.
High blood pressure — or hypertension — is one of the major cardiovascular diseases worldwide. It leads to stroke and heart disease and costs more than $300 billion each year. Around a quarter of the adult population is affected globally — including 10 million people in the UK and one in three US adults.
Published next month in the American Journal of Clinical Nutrition, the new findings show that bioactive compounds in blueberries called anthocyanins offer protection against hypertension. Compared with those who do not eat blueberries, those eating at least one serving a week reduce their risk of developing the condition by 10 per cent.
Anthocyanins belong to the bioactive family of compounds called flavonoids and are found in high amounts in blackcurrants, raspberries, aubergines, blood orange juice and blueberries. Other flavonoids are found in many fruits, vegetables, grains and herbs. The flavonoids present in tea, fruit juice, red wine and dark chocolate are already known to reduce the risk of cardiovascular disease.
This is the first large study to investigate the effect of different flavonoids on hypertension.
The team of UEA and Harvard scientists studied 134,000 women and 47,000 men from the Harvard established cohorts, the Nurses’ Health Study and the Health Professionals Follow-up Study over a period of 14 years. None of the participants had hypertension at the start of the study. Subjects were asked to complete health questionnaires every two years and their dietary intake was assessed every four years. Incidence of newly diagnosed hypertension during the 14-year period was then related to consumption of various different flavonoids.
During the study, 35,000 participants developed hypertension. Dietary information identified tea as the main contributor of flavonoids, with apples, orange juice, blueberries, red wine, and strawberries also providing important amounts. When the researchers looked at the relation between individual subclasses of flavonoids and hypertension, they found that participants consuming the highest amounts of anthocyanins (found mainly in blueberries and strawberries in this US-based population) were eight per cent less likely to be diagnosed with hypertension than those consuming the lowest amounts. The effect was even stronger in participants under 60.
The effect was stronger for blueberry rather than strawberry consumption. Compared to people who ate no blueberries, those eating at least one serving of blueberries per week were 10 per cent less likely to become hypertensive.
“Our findings are exciting and suggest that an achievable dietary intake of anthocyanins may contribute to the prevention of hypertension,” said lead author Prof Aedin Cassidy of the Department of Nutrition at UEA’s Medical School.
“Anthocyanins are readily incorporated into the diet as they are present in many commonly consumed foods. Blueberries were the richest source in this particular study as they are frequently consumed in the US. Other rich sources of anthocyanins in the UK include blackcurrants, blood oranges, aubergines and raspberries.”
The next stage of the research will be to conduct randomised controlled trials with different dietary sources of anthocyanins to define the optimal dose and sources for hypertension prevention. This will enable the development of targeted public health recommendations on how to reduce blood pressure.
Get thee to your local fruit vendor, my friends! Help your body; help yourself. Do it, do it! :)
with passion & gratitude — jennifer