June 1, at Randomly reading some of the advice on boosting the immune system yields Dr. Spend time with other people. Many health benefits of ginger you have read about here are based on clinical studies google 'ginger cancer', etc. If the answer to number three is a big yes, perhaps you should avoid the product.
Sleep and Immunity: Understanding the Link
There are a few that appear to be mildly effective. This includes Caffeine, Green Tea and Glucomannan (a fiber that can reduce appetite). However, the results are usually weak and inconsistent and certainly nothing to get excited about.