by Rebecca RuppBlueberries are not only scrumptious – they may be able to protect us from cardiovascular disease, cancer, memory loss, and maybe even PTSD in the future. Bears go bats over blueberries. In blueberry season, bears will travel miles just to get their paws – well, lips – on a ripe and scrumptious blueberry patch. And an increasing amount of scientific evidence indicates that we should all be as pro-blueberry as the bears. Blueberries these days are touted as a superfood – an unofficial term that refers to low-calorie edibles with greater-than-average (even super) nutritional and health benefits. Among these – along with the yummy blueberries – are broccoli, kale, kiwi fruit, pomegranates, beans, salmon, and sardines. The notable health value of blueberries derives in part from their lush content of antioxidant flavonoids – compounds that not only make blueberries blue, but also act to mop up free radicals. Blueberry fields turn bright red in Maine during the autumn season. Photograph by B. Anthony Stewart, National Geographic Free radicals are highly reactive molecules with the potential to damage cell integrity and mess with our all-important DNA. These are products of normal body metabolism – each of our body’s cells generates about 20 billion every day – and we also pick up a good many from pollutants and radiation in the environment. Free radicals, as destructive as molecule-gobbling Pac Men, have been implicated in everything from cardiac disease to cancer, memory loss, autoimmune disorders, and neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease. Our bodies do their best to beat these off – we have a couple of enzymes tailor-made to combat and eliminate free radicals – but with age and environmental exposure, they can begin to overwhelm us. We can help protect ourselves with antioxidant-enriched foods – and when it comes to antioxidants, blueberries are at the top of the food heap. According to the U.S.Department of Agriculture, blueberries, antioxidant-wise, out-rank everything but red beans – and red beans aren’t ahead by much. The latest in the array of blueberry bennies is their possible potential to combat post-traumatic stress disorder (PTSD). About 8 percent of the American population suffers from PTSD at some point in their lives, due to emotional or physical trauma, and – at an estimate – PTSD afflicts up to 20 percent of veterans. Current, but not particularly effective, treatments for PTSD are drugs known as selective serotonin re-uptake inhibitors or SSRIs – that is, medications that boost levels of serotonin, a neurotransmitter associated with mood disorders. A sprig of black highbush blueberry blossoms and berries from the February 1919 issue of National Geographic. Illustration by Mary E. Eaton Some recent research, however, indicates that blueberries may be a helpful alternative, at least in rats. Experiments conducted by Philip Ebenezer and colleagues at Louisiana State University involved rats which developed PTSD after being (deliberately) terrified by cats. The researchers found that rats who were fed blueberries following their traumatizing experience had markedly higher serotonin levels than rats fed a blueberry-less control diet, suggesting a better recovery. If blueberries have similar effects on neurotransmitter levels in human beings, they may help alleviate the problems of the severely traumatized. Other health benefits of blueberries have been in the news for a while. A cup of blueberries a day, according to the Journal of the Academy of Nutrition and Dietetics, may reduce the risk of cardiovascular disease. Other studies indicate that blueberries decrease the risk of prostate cancer, combat urinary tract infections, reduce age-related memory loss, and promote brain health. Various experiments have shown that blueberries boost brain power, variously upping memory, learning, and cognitive functions – among these reasoning skills, decision making, verbal comprehension, and numerical ability. To be fair, there are other foods that are also excellent sources of brain-bolstering flavonoids – among them wine, tea, dark chocolate, and tofu. But blueberries are also great sources of vitamin C – and, since a cup of blueberries adds up to a mere 80 calories, they’re not about to make you fat. What to make of all of this? Scientists tell us not to go overboard. Popular claims for superfoods can be exaggerated; and chances are that blueberries aren’t a universal panacea. But a cup a day sure can’t hurt.
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