Yeast flour that meets national food safety standards is not harmful to the body. Yeast powder is a common leavening agent, can be used for fermentation of pasta and so on, such as making steamed bread, bread, cookies often use yeast powder. Yeast powder can not only accelerate the speed of fermentation, yeast powder also contains certain nutrients, beneficial to the human body. It is generally not harmful to health. When buying yeast, it is recommended to choose yeast that meets the national food safety standards, unchecked, not the regular production of yeast is likely to not meet the national food standards, this type of yeast may lead to diarrhea and other discomforts after eating. It is recommended to buy yeast powder to choose the regular way of qualified products, according to the standard use of the product packaging, daily life discomfort, should be promptly to the hospital for examination and treatment.