 Vinegar has evidently been used as a weight loss aid for nearly 200 years. But does it work? Well, like hot sauce, it can be a nearly calorie-free way to flavor foods, and there's all sorts of tasty, exotic vinegars out there now, like fig, peach, and pomegranate to choose from. But the question is, is there something special about vinegar that helps with weight loss? Vinegar is defined simply as a dilute solution of acetic acid, which takes energy for our body to metabolize, activating an enzyme called AMPK, which is like our body's fuel gauge. If it senses that we're low at amps up energy production, it tells the body to stop storing fat and start burning fat. And so, given our obesity epidemic, it's crucial that oral compounds with high bioavailability are developed to safely induce chronic AMPK enzyme activation, which would potentially be beneficial for long-term weight loss. No need to develop such a compound, though, if you can buy it at any grocery store. We know vinegar can activate AMPK in human cells, but is the dose one might get sprinkling it on a salad enough? If you take endothelial cells, blood vessel lining cells from umbilical cords after babies are born, and expose them to various levels of acetate, which is what the acetic acid and vinegar turns into in our stomach, it appears to take concentration of at least 100 to get a really significant boost in AMPK. So how much acetate do you get in your bloodstream sprinkling about a tablespoon of vinegar on your salad? You do it 100, but only for about 15 minutes. And even at that concentration, that kind of 20-minute exposure doesn't seem to do much. Now, granted, this is an apetite dish, but we didn't have any clinical studies until we did. Double-blind trial, investigating the effects of vinegar intake on reduction of body fat and overweight men and women. Now, they call them obese, but they were actually slimmer than your average American. In Japan, they call anything over a BMI of 25 obese, whereas the average American adult is about 28.6. But anyway, they took about 150 overweight individuals and randomly split them into one of three groups, a high-dose vinegar group, where they drank a beverage containing two tablespoons of apple cider vinegar a day, a low-dose group, where they drank a beverage containing only one tablespoon of apple cider vinegar a day, and a placebo control group, where they had them drink an acidic beverage they developed to taste the same as a vinegar drink, but using a different kind of acid, so there was no acidic acid. No other changes in their diet are exercised. In fact, they monitored their diets and gave them all pedometers, so make sure that the only significant difference between the three groups was the amount of vinegar they were getting every day. This is where they started out, and within just one month, statistically significant drops in weight in both vinegar groups compared to placebo, with higher dose doing better than the low dose, which just got better and better month after month. In fact, by month three, the Do Nothing placebo group actually gained weight, as overweight people tend to do, whereas the vinegar group significantly dropped their weight. Now, was the weight loss actually significant or just kind of statistically significant? Well, that's for you to decide. This is in kilograms, so compared to placebo, the two tablespoons of vinegar a day group dropped five pounds by the end of 12 weeks. It may not sound like a lot, but they got that for just pennies a day without removing anything from their diet. And they got slimmer, up to nearly an inch off their waist, suggesting they were losing abdominal fat, but the researchers went the extra mile and put it to the test. They put the research subjects through abdominal CT scans to actually directly measure the amount of fat before and after in their bodies. They measured the amount of superficial fat, visceral fat, and total body fat. Superficial fat is the fat under your skin that makes for flabby arms and contributes to cellulite, but visceral fat is the killer. That's the fat shown here in white, building up around your internal organs that bulges out the belly. And that's the kind of fact the placebo group was putting on when they were gaining weight. Not good. Both the low dose and high dose vinegar groups were able to remove about a square inch of visceral fat off that CT scan slice. Now, like any weight loss strategy, it only works if you do it a month after they stopped the vinegar, the weight crept back up, but that's just additional evidence that the vinegar was working. But how? A group of researchers in the UK suggested an explanation. Vinegar beverages are gross. They made a so-called palatable beverage by mixing a fruity syrup in vinegar and water, then went out of the way to make a really nasty, unpalatable vinegar beverage, both with white wine vinegar, which were so unpleasant the study subjects actually felt nauseous after drinking them, so ate less of the meal they gave it with. So there you go. Vinegar helps with both appetite control and food intake, though these effects were largely due to the fruity vinegar concoctions invoking feelings of nausea. So is that what was going on here? Were the vinegar groups just eating less? No. The vinegar groups were eating about the same compared to placebo, same diet, more weight loss, thanks perhaps to the acetic acid's impact on AMPK. Now the CT scans make this a very expensive study, so I was not surprised it was funded by a company that sells vinegars, which is good, since otherwise we wouldn't have these amazing data, but it's also bad, because it always leaves you wondering if the funding source somehow manipulated the results. But the nice thing about company's funding study is about healthy foods, whether it's some kiwifruit company or the National Watermelon Promotion Board, watermelon.org, check it out, is that what's the worst that can happen? Here, for example, if the findings turned out to be bogus, worse comes to worst, your salad would just be tastier.