Beer hops are good for the brain and can actually improve concentration and speed up thought processes, according to a new scientific study.

The research, which will be music to the ears of beer lovers, found that consuming hops also reduced stress levels and improved mood.

And perhaps surprisingly, those who took supplements containing bitter hop extracts, displayed better memory recall and were better able to solve mental puzzles.

The study by Japanese scientists suggests that the acid found in bitter hops, and known as MHBA, could be used to help combat dementia.

It found that there was notable improvement in the cognitive function of participants after 12 weeks of taking the supplement.

Scientists based at Juntendo University Faculty of Medicine and the Fukushima Healthcare Center carried out the research on 100 otherwise healthy people aged 45 to 69 who had demonstrated Selective Cognitive Decline (SCD), defined as 'worsening memory loss'.

While some were given placebos, others were given a daily dose of MHBA.

They all carried out a series of mental tests and assessments at the outset and again after 12 weeks, while saliva and blood samples were tested to analyse the affect on hormones and chemicals linked to cognitive function and stress, for example.

The report states: "We observed improved attention and reduced stress after neuropsychological tests (assessed by ?-endorphin) in the participants who received MHBA supplements."

The study's authors concluded: "The present study results showed that MHBA supplementation improved mental processing speed, attention, and concentration and reduced mental stress after intellectual work in healthy adults aged 45 to 69 years with Selective Cognitive Decline.

"In particular, early intervention through MHBA supplementation in persons with SCD could be successful in improving cognitive function."

The scientists even found that MHBA appeared to improve energy metabolism in overweight subjects, suggesting it may help keep you trim as well.

The study has been published in the latest edition of the Journal of Alzheimer's Disease.