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Onions are potentially a good source of antioxidants, though, interestingly, the antioxidants are concentrated in the outer layers immediately under the papery peel. Unfortunately, most consumers discard these most nutrient-rich outermost layers, thus losing a valuable part. Here are some numbers. Look at that! More than 10 times more antioxidants in the outer layer of white onions, compared to the core. You’ll also note that yellow onions in general have more antioxidants than white. And red onions beat them both, based on three different antioxidant testing methods. That’s why I always try to buy red. Though red onions are indeed slightly better, yellow or white onions are no slouches, containing considerable levels of antioxidant activity. So, nutritious, sure, but are there any particular clinical benefits to onion consumption? There are grammatically challenged titles like this in the medical literature purporting all sorts of miraculous benefits. But what do they base these claims on?
For example, here’s a review purporting to have evidence that testosterone in males is enhanced by onion, but the researchers were talking about studies like this on the effects of onion juice after testicular torsion . . . in rats. Who cares what happens after a rat testicle is rotated 720 degrees counterclockwise? (Except, of course, the rat.) You don’t know what happens in people until you put human testes to the test and . . . onion extracts don’t appear to work.
Okay, what about bone health? Evidently, older white women who consumed onions at least once a day had an overall bone density that was 5 percent greater than individuals who consumed onions no more than once a month (P < 0.03). Now 5 percent might not sound like a lot, but that improvement in bone density could potentially translate into decreasing their risk of hip fracture by more than 20 percent if, indeed, it was cause and effect.
Daily administration of onion did cause a big bump in bone density. This opens the possibility for a low-cost, safe, and effective nutritional approach to osteoporosis and—you guessed it—in the rat. Another rodent study. Rats!
But finally, here we go. Tremendous strides have been made in treating osteoporosis with drugs, but they have the potential for serious adverse side effects, so scientists have drawn their attention to natural remedies. So, let’s randomize people to drink onion juice or placebo onion juice. I don’t know what sounds worse: sugary onion juice or fake sugary onion juice. And as if drinking onion juice wasn’t bad enough, it was all for nothing. It didn’t even work.
What about the anti-allergy activities of shallots, and any therapeutic effects on helping allergic runny noses? Sixteen such patients were randomized equally into an antihistamine group, or a group that got antihistamines plus some capsules containing dried shallot powder. And it looked like the shallot group did better, but there was actually no statistically significant difference in total symptoms between the two groups; so, another #OnionFail. There has to be something onions can do.
What about testing the effects of fresh yellow onion consumption on breast cancer patients to try to decrease the toxic effects of a chemotherapy drug called doxorubicin? Unfortunately, no significant benefit was found on decreasing damage to the liver or heart.
But here we go . . . finally, a clinical benefit to onions. The consumption of fresh yellow onion ameliorates the high blood sugars and insulin resistance in breast cancer patients during doxorubicin-based chemotherapy. Doxorubicin isn’t just toxic to the liver and heart, but it may also contribute to insulin resistance. So, let’s do a randomized, triple-blind, controlled clinical trial randomizing patients to like a whole onion a day. or a third of an onion a day. What happened? The high-onion group experienced a significant decrease in blood sugars and insulin resistance compared to the low-onion group. They went up in the low-onion group, but down in the high-onion group. So, make onions your friend. What’s the worst that can happen—a little onion breath and BO? Probably the least of your worries if you have cancer on chemotherapy.
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