Yam rotted a little peeled off is not recommended to eat anymore, it is harmful to the body and can cause the risk of disease. Whether it is a yam, or any other vegetables or fruits, if a part of it is rotten, then the rest of it is also best not to eat. Because the yam visible to the naked eye ulceration, it is likely to be caused by the growth of germs, such as bacteria, molds and other causes of rotting and ulceration, although the partial ulceration, the naked eye is easy to see, but in the process of rotting the harmful, toxic substances will be produced through the moisture diffusion, contamination of the rest of the part, is not visible to the naked eye. Secondly, some molds and their toxins themselves also have carcinogenic effects, such as aflatoxin, which is very harmful to the human body after consumption. Therefore, whether it is yam, or any other vegetables, fruits, if a part of the rot, even if you have eliminated the rotting part, the germs and toxins lurking in the whole vegetables, fruits inside is no way to completely cut off, such vegetables, fruits can not be eaten.