Can ganoderma help in weight loss?

Yes. It can help, but reading about reishi mushroom makes it a bit unclear as to safety. Some reports state that it harms the liver and others state that it protects it. My advice would be yes take some if you have no liver issues but don't overdoit.
Yes. Ganoderma(reishi mushroom) is known to enhance your rate of metabolism. As your metabolic rate increases, your body uses more energy to digest food more effectively. To deliver this increased need for energy your body uses up more calories and your fat deposits in your body. This, clearly, can result in weight management. Reishi helps detox liver and naturally brings down blood pressure- good rx.