Dark roasted low-acid arabica coffee & Chaga mushroom. Boost - One of Chaga's most well-known health benefits is its ability to support healthy immune function. Compounds called polysaccharides that are found in Chaga have precisely this benefit. Tree mushrooms like Chaga have been used for thousands of years to support immune health and inflammation systems and continue to be an area of study for researchers. Our caffeine supplement contains only organic and natural ingredients. UK/US: Caffeine supplement as a drink. Contains 90 mg caffeine and 226 mg Chaga per serving. Ingredients: Caffeine from organic coffee beans 98%, organic instant Chaga extract from Inonotus obliquus L.