Ganoderma lucidum, better known as the reishi mushroom, was able to prevent weight gain in mice according to a new study. Whilst not a magic bullet exactly, in an experiment mice fed a high fat diet alongside the reishi gained significantly less weight than mice on the same diet without it. The supplement didn't cause weight loss in the normal diet group, but it looks like it might be useful if you're having a 'bad' food day. The research found that reishi is able to boost 'good' bacteria in the gut and also reduces inflammation. As both gut microbiome changes and inflammation are linked to obesity, consuming reishi may be a way to ameliorate a heavy diet.
Read more at NHS Choices