Bluberries May Lessen Heart Attacks in Women and What Do Blueberries Have in Common with Viagra?
What do Bluberries and Viagra Have in Common? They Both Involve Interaction with the Inner Lining of Blood Vessels
Researchers at Harvard have published a study suggesting that blueberries may help women lower the chance of a heart attack. Beginning in 1991, they tracked more than 100,000 women ages 25 to 42 with food-frequency questionnaires every four years through 2009. They found that women who ate more blueberries and strawberries had a lower chance of heart attack. They write, "Our findings suggest that bioactive compounds present in red and blue fruits and vegetables commonly consumed in the habitual diet may be associated with a reduced risk of MI (myocardial infarction a.k.a heart attack) in young and middle-aged women".
Heart attacks can happen because of a disturbance to the endothelium, the inner lining of blood vessels, which can lead to the formation of a clot that results in a heart attack. The inner lining of the blood vessels is surprisingly important in the function of the heart and the control of various body functions. The inner lining of the arteries, the endothelium is surprisingly complex and surprisingly important. The endothelial function includes producing vital chemicals that help to control the body.
"Combined intake of 2 anthocyanin-rich foods, blueberries and strawberries, tended to be associated with a decreased risk of MI (hazard ratio, 0.66; 95% confidence interval, 0.40–1.08) in a comparison of those consuming >3 servings a week and those with lower intake".They suspect that the chemical in blueberries may impact the endothelium of arteries.
The endothelium is the thin layer of cells that lines the interior surface of blood vessels, the inner lining. The endothelium among other things, produces nitric oxide, a vasodilator (makes arteries wider), (nitric oxide is also produced elsewhere) which is a potent signaling molecule, that happens to be a gas and thus can move more easily among cells that can cause widening of the blood vessels,i.e. vasodilation. Widening the blood vessels can be good as when it lowers your blood pressure or bad if it lowers it too much as in shock. It is interesting that drugs such as Viagra work through the nitric oxide pathway.
Our current knowledge of modifiable risk factors to prevent myocardial infarction in young and middle-aged women is limited, and the impact of diet is largely unknown. Dietary flavonoids (such as those found in blueberries) exert potential beneficial effects on endothelial function in short-term trials; however, the relationship between habitual intake and risk of MI in women is unknown.
"Combined intake of 2 anthocyanin-rich foods, blueberries and strawberries, tended to be associated with a decreased risk of MI (hazard ratio, 0.66; 95% confidence interval, 0.40–1.08) in a comparison of those consuming >3 servings a week and those with lower intake. Intakes of other flavonoid subclasses were not significantly associated with MI risk".
"After adjusting for many dietary, behavioral and physiological risk factors, the scientists found that compared with those below the 20th percentile in anthocyanin intake, those above the 80th percentile were 32 percent less likely to have a heart attack. Other flavonoids were not significantly associated with reduced risk".
"Women who ate more than three servings of blueberries or strawberries a week - the most common anthocyanin-rich foods consumed - had a 34 percent lower risk than those who ate less.
From a dietary perspective, growing evidence supports the beneficial effects of dietary flavonoids on endothelial function and blood pressure,suggesting that flavonoids might be more likely than other dietary factors to lower the risk of CHD in predominantly young women.Specific flavonoids appear to improve endothelial function by exerting antiinflammatory effects, inhibiting low-density lipoprotein oxidation and endothelial NADPH oxidase, modulating nitric oxide synthase activity/expression, and augmenting nitric oxide status. Flavonoids are widely distributed in many plant-based foods and beverages, including fruits, vegetables, tea, and wine, and the subclasses commonly consumed in the US diet include flavanones, anthocyanins, flavan-3-ols, flavonols, flavones, and polymeric flavonoids.