Open sesame - placebo or not?
There has been a spate of advertisements promoting "oil pulling" - gargling with sesame oil - as a "cure all" for humanity's diseases. Advertisements by a leading brand "Idhayam" in Tamil Nadu cite a study undertaken by Dr.Vetrivel. They subjected 22 subjects to "oil pulling" for about a month. Among other things, the study concludes that there was an increase of Haemoglobin level, a rise in WBC count, a fall in Eosinophil count, blood sugar level, urea, serum creatinine and cholesterol level in 12 subjects on an average! Patients reported deeper sleep, odour-free mouths, increased agility, reduced hypertension, better skin complexion and so on, the study claims.
This campaign has created a buying frenzy for "Idhayam Gingelly Oil" in the market. There could be no better way to increase the sales for a market leader than to increase consumption.
Economics apart, the purported study appeared too good to be true and I looked at it more deeply. One fallacy that I could find was that while they had a "control set" of subjects take up this treatment, they failed to have another control group undergo a treatment with a placebo to rule out placebo effect. But, still so many biochemical changes are unlikely to happen simply due to placebo effect. While I'd earlier vociferously defended Sesame oil's medicinal properties here, I was sceptical how mere gargling would cause so much biochemical effect. Partly out of curiosity and partly due to my father's insistence, I'm trying it for the past few days. The only notable thing I observe is a reduction in the amount of dental plaque. It's plausible given that oils are good solvents.