Dark berries such as blueberries, blackberries and acai berries have always been super healthy. They contain resveratrol which has been found to raise testosterone levels, block estrogen synthesis and possibly activate androgen receptors.
Calcium D-glucarate is found in fruits and vegetables. D-glucaric acid is believed to inhibit the action of the enzyme beta-glucuronidase, which is associated with an increased risk of hormone-
The anti-oxidant content of dark berries is extremely high, they make a perfect gout prevention food.
Blueberries contain two simple sugars, fructose and glucose in relatively small amounts (10% by weight). So only glucose will will trigger an insulin response. Naturally occurring fructose from fruits isn’t a bad thing (HFCS in sodas and processed food are the ones to avoid).
Source: ncbi.nlm.nih.gov, anabolicmen.com