Wild blueberry vs. sugar

The study, published in the Journal of Agricultural and Food Chemistry, was a crossover trial: half of the 20 men in the study were assigned to receive a test drink for the first six-week phase and placebo for the second six-week phase, while the other half received the opposite. The test drink was made with 25 grams of wild blueberry powder and water, and the placebo drink contained 14.5 grams of sugars (fructose and glucose), blueberry flavor, artificial colors, and citric acid.

Researchers examined cultures of stool samples taken at the beginning and end of each phase. These showed:

• Bifidobacteria doubled after the wild blueberry drink but was unchanged after placebo.
• Lactobacillus acidophilus increased almost 7 times after the blueberry drink and 5.5 times after placebo.
• Levels of other normal intestinal bacteria were essentially unchanged by the blueberry and placebo drinks.

Bifidobacteria prefer wild blueberry

"The results of our study suggest that regular consumption of a wild blueberry drink can shift the composition of the intestinal microbiota, increasing in particular bifidobacteria, a group of commensal intestinal microorganisms demonstrated to benefit human health. Ongoing experiments are demonstrating that bioactive components of wild blueberry, such as dietary fibers and polyphenols, are responsible for the selective stimulation of the growth of these health-promoting bacteria,” said study co-authors Dr. Patrizia Riso and Dr. Simone Gugliemetti at the University of Milan, Italy.

Supporting healthy gut bacteria

Our dietary habits have a profound influence on the make-up of our gut bacteria. Here are some things you can do to help the healthiest bacteria thrive:

• Eat lots of fiber. Insoluble fiber, or roughage, helps keep intestinal bacterial colonies strong.
• Focus on fruits and vegetables. Bananas, onions, garlic, Jerusalem artichoke (or sunchoke), and asparagus are especially high in a type of natural carbohydrate that promotes the growth of healthy gut bacteria.
• Choose fermented and cultured foods. Yogurt, kefir, unpasteurized sauerkraut, kimchi, and miso are among the many tasty foods that contain lactobacilli and other beneficial bacterial strains.

(J Agric Food Chem 2011;dx.doi.org/10.1021/jf2028686)