Could Turmeric and Curcumin Aid Weight Loss?
Curcumin is best known as the primary bioactive polyphenol in turmeric, a spice that has been revered both for its culinary uses and health benefits. Over the past decades, curcumin has been researched as a potential treatment for everything from cataracts to Crohn's disease to rheumatoid arthritis. Considering the prevalence of obesity the modern world and the well documented biological properties of curcumin, it is not surprising that curcumin extracted from turmeric root has also been evaluated as a potential weight loss supplement.
Evidence Linking Turmeric and Curcumin to Weight Loss
In one of the earlier studies investigating the potential weight loss effects of turmeric, administration of curcumin reduced weight gain in female rats fed high fat diets. This study, which appeared in the June 1987 edition of Journal of Biosciences, also found that curcumin tended to reduce liver weight as well as blood triglyceride and free fatty acids levels.
Intrigued by this and other early studies documenting the beneficial effects of turmeric or its main bioactive ingredient curcumin, a team of scientists at Tufts University decided to systematically review existing research investigating the potential weight loss benefits of turmeric and curcumin. Their review, which was published in the journal Nutrients in 2010, was part of a larger study on dietary polyphenols and obesity.
The Tufts researchers reported that not only has curcumin been found to affect energy metabolism in adipocyte cultures (i.e. fat cell cultures), but that also numerous animal studies suggest that this powerful turmeric polyphenol may have beneficial effects on energy metabolism as well as body fat levels and body weight. According to the researchers, the observed anti-obesity effects of curcumin may linked to, among other things, the ability of curcumin to inhibit the development of new blood vessels in fat tissue, to hinder the conversion of pre-adipocytes to adipocytes, and to suppress transcription factors that play a key role in lipogenesis. (Lipogenesis refers to the process by which simple sugars such as glucose are converted to fatty acids.)
It has also been suggested that curcumin and turmeric might help reverse leptin resistance, which in turn might help combat excess body weight and obesity. For those who are not familiar with the term, leptin resistance refers to a state in which leptin signaling is not working properly. Leptin is a complex hormone that normally regulates food intake and fat storage, but in people with leptin resistance, leptin cannot reach its target site, the hypothalamus in the brain. This causes a disruption in the mechanism that is supposed to keep you from overeating and storing unnecessary fat, resulting in weight gain or difficulty losing weight.
The Bottom Line
Research on turmeric and curcumin in the context of weight loss is still in its infancy, and further studies – especially well-controlled clinical trials involving humans – are necessary before any reliable conclusions can be made about the effectiveness of turmeric or curcumin as a natural weight loss aid. However, if you already want to give turmeric a try, go ahead – as with any food remedy, you can always abandon if it doesn't work. Note, though, that turmeric, like most other foods, may cause adverse reactions in some people, and some people with specific conditions may be advised to limit or avoid using turmeric or curcumin supplements. Therefore, if you suffer from a specific health problem, are pregnant or breastfeeding, or take any medications, it is best to consult with your doctor before you start experimenting with turmeric as a weight loss aid.