Metabolic syndrome is a health condition affecting about 34% of adults in the US, putting them at risk for cardiovascular disease, diabetes, stroke and other diseases. Now, researchers from Oregon State University say a flavonoid found in hops and beer could reduce weight gain and improve markers of metabolic syndrome.
Results of the study are published in the journal Archives of Biochemistry and Biophysics.
The researchers - led by Cristobal Miranda, a research assistant professor at the university - found specific intake levels of the hops flavonoid, called xanthohumol, which improved metabolic syndrome markers in laboratory mice.
According to the American Heart Association (AHA), the underlying causes of metabolic syndrome are overweight and obesity, physical inactivity and genetic factors. Risks associated with the condition can be reduced by lowering weight, increasing physical activity and eating a heart-healthy diet.
Being clinically diagnosed with three or more of several conditions is what defines metabolic syndrome. These conditions include: abdominal obesity, elevated lipids, high blood pressure, insulin resistance or impaired glucose tolerance.
The researchers note that obesity and its related disorders account for up to 10% of health care expenditures in the US.
Previously, xanthohumol has been researched for its potential health benefits, alongside other flavonoids found in tea, garlic, chocolate, apples and blueberries.
Earlier this year, a study published in The BMJ suggested eating more flavonoid-rich fruits and vegetables to prevent weight gain, for example.
Xanthohumol reduced LDL cholesterol and insulin levels in mice
To investigate what levels of xanthohumol have an effect on metabolic syndrome, the researchers gave varying levels of the flavonoid to laboratory mice that were fed a high-fat diet.
Results showed that, compared with animals that were not given any xanthohumol, the laboratory mice that were given the highest dosage had an 80% reduction in their LDL - or "bad" - cholesterol. In addition, their insulin levels dropped 42%, and their IL-6 levels, which is a biomarker of inflammation, dropped by 78%.
Furthermore, the researchers found that although the mice given the flavonoid were still growing - because they were eating a rich diet and becoming obese - their weight increased by 22% less than those not receiving xanthohumol. This is despite the fact that they all ate the same amount of food.
Interestingly, the researchers say consuming the flavonoid seems to increase oxygen consumption and metabolic rate, which has major implications for weight control.
Commenting on their findings, Miranda says:
"This is the first time we've seen one compound with the potential to address so many health problems. These were very dramatic improvements."
Through the study, the researchers were also able to pinpoint one of the mechanisms of the flavonoid. Apparently, it lowers plasma levels of PCSK9, which is a protein that acts on cholesterol levels.
They hope that lowering levels of this protein will help to clear LDL cholesterol from the blood.
Amount too high to obtain through ordinary dietary intake
Before using this study as a free pass to drink copious amounts of beer, however, the researchers suggest looking closely at the doses used in the study.
Although xanthohumol is found naturally in hops and beer, the study used 60 mg per kg of body weight per day, which is the human equivalent of 350 mg for a person weighing 70 kg (154 lbs) per day.
In short, this would mean that a human adult would have to drink 3,500 pints of beer each day to get the correct intake as reported in the study. Though this would not be possible - or advisable to undertake - the researchers say this amount of xanthohumol could be obtained through a dietary supplement.
Although their results are very promising, the researchers note that more research needs to be undertaken to show safety and efficacy in humans.
"Work is still needed to further demonstrate the safety of high dosages of xanthohumol," says Prof. Fred Stevens, study corresponding author, "but dosages 15-30 times higher than we used have already been given to animals with no apparent problems."
He adds that "this might provide an effective treatment for metabolic syndrome at a very low cost."
Medical News Today previously investigated how eating more flavonoid-rich foods could reduce risk of erectile dysfunction in men.