In my last video on onions, I talked about the data supporting—or not supporting—the role of onions in boosting testosterone in men, protecting bone health, controlling allergies, and dealing with chemo side effects. What about weight loss? Enter the effect of steamed onion consumption on body fat in overweight subjects. The researchers used steamed onions so they could better disguise it against placebo and dried it into onion powder and gave people just a miniscule amount—about an eighth of a teaspoon a day. Surely, a little daily dusting of onion powder isn’t going to affect the course of people’s weight, but check out these results, reported in the abstract: a significant reduction in body fat mass on both DEXA scan and measured by CT scan, a significant decrease in the areas of whole fat, visceral fat, and subcutaneous fat.
A more recent study tried four teaspoons of onion powder a day, and similarly failed to accelerate the loss of body fat compared to placebo––but the placebo was also four teaspoons of onion powder a day. They used yellow onions versus white onions, and it seems they both may have caused a loss of body fat, without a significant difference between them. Either way, you can look at these two studies and say, yeah, but what are the downsides? I mean just an eighth teaspoon of onion powder a day. Why not give it a try? Can’t hurt, but we just don’t have confidence that it’s going to actually help.
Turning now to polycystic ovary syndrome, also known as P.C.O.S., or PCOS. It’s one of the most common hormone disorders, affecting 5 to 10 percent of reproductive-aged women. In addition to symptoms like irregular periods, PCOS is also a pre-diabetic state, with decreased insulin sensitivity. PCOS treatment is a big challenge due to medication side effects. Therefore, what about using dietary options? How about a randomized controlled clinical trial of raw red onion intake?
Why onions? Well, onion extracts evidently help in diabetic rats and, more importantly, in diabetic humans, but evidently not in non-diabetic humans. PCOS sufferers are kind of pre-diabetic; so, would it work for them? First, let’s look at those other two studies. Here’s the diabetic one, on the metabolic effects of onion and green beans. Diabetics spent a week eating either a small onion a day, or the same diet but instead with about five cups of green beans instead, and they both worked. The onion dropped people’s blood sugars by about 10 percent, and the green beans more like 15 percent.
Women with PCOS are seven times more likely to have a heart attack, the number one killer of women. But raw red onion consumption appears to be effective as a cholesterol-lowering food, though the high-onion group only dropped their LDL cholesterol about five points––not significantly different than the low onion group.
I did find this study from nearly 50 years ago where researchers fed people nearly an entire stick of butter, and their cholesterol shot up about 30 points within hours of consumption, but only nine points or three points when combined with about a third cup of raw or boiled onion––the moral of the story being…don’t eat a stick of butter.