Japanese researchers a couple years ago documented that daily vinegar reduces body weight, fat mass, and triglycerides in overweight Japanese adults.
Beverages containing vinegar are commonly consumed in Japan. The main component—4 to 8%— of vinegar is acetic acid. Vinegar can lower cholesterol levels, lower blood pressure, and limit increases in blood sugar after meals.
Japanese researchers studied the effects of vinegar on 175 overweight—body mass index between 25 and 30—subjects aged 25 to 60. Men totaled 111; women 64. Average weight 74.4 kg (164 pounds). They were divided into three groups that received either a placebo drink, 15 ml apple vinegar (750 mg of acetic acid), or 30 ml apple vinegar (1,500 mg acetic acid). Placebo and vinegar were mixed into 500 ml of a beverage, half of which was drunk twice daily after breakfast and supper for 12 weeks. Changes in body fat were measured with CT technology. Subjects were told to eat and exercise as usual.
By the end of the 12 weeks, weight had decreased by 1-2 kg (2.2 to 4.4 pounds) in the vinegar drinkers, with 30 ml of vinegar a bit more effective. CT scanning showed that the lost weight was fat mass rather than muscle or water. Triglyceride levels in the vinegar groups fell by about 20%. The placebo drinkers saw no changes.
Four weeks after the intervention ended, subjects were retested: values had returned to their baseline, pre-study levels.
The scientists report that the acetic acid in vinegar inhibits production of fat and may stimulate burning of fat as fuel. Although vinegar contains many other ingredients, they think the acetic acid is responsible for the observed changes.
It’s possible that apple vinegar components other than acetic acid led to the weight loss and lowered triglyceride levels. Further study could clarify this.
Remember that weight lossed was regained after the vinegar was discontinued. Would you want to drink the vinegar indefinitely to maintain a loss of 2-4 pounds? Probably not, unless you like vinegar. But adding 12 weeks of vinegar to your weight-loss program might be worth it if you’re just preparing for a school reunion or the start of swimsuit season.
These results may or may not be applicable to non-Japanese races.
This study supports the use of vinaigrette as a salad or vegetable dressing in people trying to lose weight with diets such as the Ketogenic Mediterranean Diet or Advanced Mediterranean Diet. Vinaigrettes are combinations of olive oil and vinegar, often with various spices added. If you eat a salad twice a day, it would be easy to add 15 ml (1 tbsp) of vinegar to your diet daily.
With a little imagination, you could come up with other ways to add 15–30 ml (1–2 tbsp) of vinegar to your diet.
Update May 17, 2012: After posting this, I ran across on article on the Apple Cider Vinegar Diet at Life123.
Reference: Kondo, Toomoo, et al. Vinegar intake reduces body weight, body fat mass, and serum triglyceride levels in obese Japanese subjects. Bioscience, Biotechnology, and Biochemistry, 73 (2009): 1,837-1,843.