Drinking 1-2 glasses of red grape juice or red wine a day is scientifically proven to improve the brain health due to the bioactive components of the grapes, in particular resveratrol. Resveratrol seems to be capable of crossing the blood-brain barrier and directly protecting your brain from the harmful activities of free radicals. It is also able to improve blood flow to the brain, providing the brain with the necessary oxygen and glucose to perform its tasks.
You need a relatively high dose (150-1000 mg/day) to notice any effect of resveratrol as it has a low bioavailability. Just to compare, 1 glass of red wine (150 ml) has approximately 0.03-1.07 mg of resveratrol and red grape juice contains 0.017-1.30 mg. Even without doing the math, you can see that you have to drink A LOT to benefit from this bioactive component. So how can our brain experience the positive effects of resveratrol in small doses from red grape juice or wine, if we don’t meet 150 mg/day?
Therefore there are good reasons to believe that resveratrol is just one of the many other grape components that provide us with the beneficial effects of grapes and its products on our brain and the rest of the central nervous system.
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