Study questions effectiveness of coffee for weight loss

Posted by AFN Staff Writers on 3rd June 2013

Western Australian researchers hoping to demonstrate improved cardiovascular function among coffee lovers have found that drinking too much of the popular brew may actually be linked to worsening of the metabolic syndrome.

The study, published in May 2013 in the Journal of Agricultural and Food Chemistry, by researchers from the Western Australian Institute for Medical Research (WAIMR) and the University of Western Australia’s School of Medicine and Pharmacology looked at a compound known as Chlorogenic Acid (CGA).

“Studies have shown that coffee consumption lowers the risk of developing type 2 diabetes,” said Professor Kevin Croft, from the University of Western Australia’s School of Medicine and Pharmacology. “This also included research on decaffeinated coffee, which suggested that the health benefits are from a compound in coffee apart from caffeine,” he said.

With this in mind, the researchers studied the effects of Polyphenols, including CGAs, which are very rich in coffee but also found in tea and some fruits, such as plum. The CGAs were previously known for their health benefits, increasing insulin sensitivity and reducing blood pressure and body fat accumulation.

“However, this study proved the opposite in dosages equivalent to five or six cups of coffee per day,”said Professor Vance Matthews, WAIMR’s Assistant Professor.

Coffee compounds caused fat retention

The study found that the equivalent dose of CGA fed to laboratory mice affected the utilisation of fat in the liver and caused abnormal retention of fat within cells. The obese mice also had a tendency for a higher degree of glucose intolerance and increased insulin resistance.

However, Assistant Professor Matthews said that it was still okay for people to drink moderate amounts of coffee.

“It seems that the health effects are dose-dependent. A moderate intake of coffee, up to three to four cups a day, still seems to decrease the risk of developing diseases such as cardiovascular disease and type 2 diabetes,” Assistant Professor Matthews said.

“Everybody knows about the effects of caffeine, but when we’re considering our lifestyle choices it’s important to remember that compounds such as CGA can have an effect on our health if they’re not consumed in moderation,” he added.

The researchers also found that CGA doesn’t prevent weight gain when used at higher doses in obese laboratory mice fed a high-fat diet.

“People might be wasting their money if they’re buying expensive products like green coffee bean dietary supplements, which are currently considered to be amazing weight loss products,” Professor Croft said.

Coffee and caffeine: health debate

The health benefits, or otherwise, of caffeine and coffee are widely debated.

Australian Food News reported in March 2013 that researchers had found that drinking Greek coffee might be the key to leading a longer life.

But caffeine has been linked to negative outcomes. Australian Food News reported in May 2013 that the US Food and Drug Authority had announced it would investigate the safety of caffeine in foods, following earlier news that its European counterpart would do the same.