28. Jun, 2017

Apple cider vinegar and weight loss

Claims are based on just one human clinical trial back in 2009, though there have also been a couple of animal studies. These don't always translate to humans though, and that's why we need to conduct a reasonable amount of human trials in various populations before we can say something is effective. There are a couple of issues with the trial, though it was generally quite well-designed. 

  1. The subjects studied were 155 obese Japanese men (97)and women (58), with almost twice the number of men. Ethnic differences mean the results are not transferable to a non-Japanese population.
  2. An isocaloric diet was followed. This is a carefully monitored weight loss diet.

The 4 week post-intervention measurement showed that the placebo group weight remained steady, but both the low & high dose groups had started to regain their loss. This is the body's normal response to quick weight loss- to get back to what it thinks is the 'right' weight, but more on that in another post. 

So a slight decrease in a very specific population, that isn't maintained in the abscence of an isocaloric diet, is quite a silly result to be basing worldwide weight loss claims on. 

It has however proved to be a pretty good marketing tool for manufacturers, because they got people to start and keep buying their product for a completely new (albeit false) use.

A close examination of the research has shown it means very little to Australians. Not even those of Japanese descent, because they're in an environment with a very different food supply. 

The most significant result in my opinion was the lowering of triglycerides, because it corroborates the results of animal studies. As mentioned earlier though, more human trials in various populations are needed before we can come to any conclusions. Until then, manufacturers will have to maintain the use of the word 'may' and the phrase 'there is some evidence' if they're to avoid penalties for misleading health claims. Sadly, there is no regulation of internet 'wellness gurus' and websites, so the myths persist...

References: 

Coles 2015, Natural Apple Cider Vinegar, Coles Online, <https://shop.coles.com.au/a/a-national/product/melrose-naturals-apple-cider-vinegar>

Kondo, T, Kishi, M, Fushimi, T, Ugajin, S & Kaga, T 2009, 'Vinegar Intake Reduces Body Weight, Body Fat Mass and Serum Triglyceride Levels in Obese Japanese Subjects', Bioscience, Biotechnology and Biochemistry, vol.73, no.8, pp.1837-1843.