Hop extract could reduce belly fat in overweight people, study finds

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Scientists in a recent study found that hop extract reduces belly fat effectively in healthy overweight adults.

Hops are the flowers (also called seed cones or strobiles) of the hop plant Humulus lupulus.

They are used primarily as a bittering, flavoring, and stability agent in beer, to which, in addition to bitterness, they impart floral, fruity, or citrus flavors and aromas.

Hops are also used for various purposes in other beverages and herbal medicine.

Iso-α-acids, the bitter component of beer, have been found to reduce body fat in humans.

But the bitterness induced by effective doses of iso-α-acids precludes their acceptance as a nutrient.

The matured hop bitter acids (MHBA) of oxidized hops appear to have a more pleasant bitterness compared to the sharper bitterness of iso-α-acids.

Recent research has found that MHBA is primarily composed of oxides derived from α-acids, and structurally similar to iso-α-acids.

In the study, the team examined the effects of matured hop extract (MHE) containing MHBA on reducing belly fat in healthy overweight people with a body mass index (BMI) of 25 to below 30 kg/m(2).

Matured hop extract is made from aged hops through a water-extraction process.

It contains one-tenth the bitterness of hops and can be mixed with various food and beverages, and is essentially risk-free for people of all ages including children.

In the study, the team tested 200 men and women aged 20 to below 65 years who were assigned to two groups.

During a 12-week study period, people in each group drank 350 mL of test beverage every day.

The beverage either contains MHE (with 35 mg MHBA), i.e. the namely active beverage, or a placebo beverage without MHE.

The team used CT scanning to examine the reduction of the belly fat area.

The researchers found that compared to the control group, there was a big reduction in the visceral fat after 8 and 12 weeks, and in the total fat after 12 weeks in the hop extract group.

Visceral fat is fat that wraps around your abdominal organs deep inside your body.

This type of fat, more common in men, is found deeper inside your stomach, under your abdominal muscles, and around your vital organs.

This dangerous type of fat has been linked to heart disease, Type 2 diabetes, high cholesterol, certain cancers, and stroke.

The team also found a decrease in body fat ratio in the Hop group compared to the placebo group.

Body fat percentage (BFP) is the total mass of fat divided by total body mass; body fat includes essential body fat and storage body fat.

There were no adverse effects related to the test beverages or abnormal changes in the circulatory, blood, and urine in either group.

The team concluded that drinking matured hop extract could safely reduce body fat, particularly the abdominal visceral fat of healthy overweight people.

One limitation of the study is that it only lasted 12 weeks, so the effects of hop extract may be short-term instead of long-term.

More research is needed to see the long-term health benefits of hop and whether the benefits would change over time.

The research is published in Nutrition Journal and was conducted by Yumie Morimoto-Kobayashi et al at Kirin Company in Japan.

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