It depends.

Dioscorea opposita is a mature rhizome of Dioscorea in Dioscoreaceae. It is sweet and warm, and enters the lung, spleen and kidney. It contains a lot of vitamins, cellulose, starch, protein and various minerals. If eaten in moderation, it can strengthen the spleen. Kidney-tonifying and other effects.

Whether yam is green or not depends mainly on what causes it to turn green. If it turns green due to the development of yam, it can be eaten normally and will not pose a threat to human health, but the nutritional value of yam will be reduced.

However, if the green color of yam is caused by bacteria and microorganisms, such yam will increase the burden on human stomach after eating, so it should not be eaten. 2 Can iron stick yam be eaten with a blue layer under the skin? < P > Yes.

The iron stick yam turns blue, which may be because the iron stick yam is exposed to sufficient light, and the enzyme substances in it will turn blue due to sun-qi oxidation. At this time, the iron stick yam is about to sprout, so it is edible.

Secondly, if the iron-stick yam comes into contact with the iron container, the components of the iron-stick yam will react with iron to generate ferrous ions, which may also cause the iron-stick yam to turn blue. At this time, you only need to clean it and eat it.

however, if the iron stick yam is blue caused by bacteria and mildew caused by microorganisms, then the iron stick yam should not be eaten at this time, otherwise it will easily increase the burden on the human stomach. 3. Can other parts of Chinese yam be eaten when its head is rotten? < P > Eating is not recommended.

Because of the high nutritional value of yam, after yam rots, some people will remove the rotten parts and then eat the rest, but this is actually not good.

The rotten yam shows that a large number of bacteria and microorganisms have been bred, and it may seem that only a small part of it is rotten, but in fact, most of the yam has been bred with bacteria and microorganisms, which will easily increase the burden on the human stomach and pose a threat to its own health after eating. 4 three kinds of yam can't be eaten by people

Although yam is good, not everyone can eat it. Constipated people

Yam contains a lot of vitamins, cellulose and amylase substances. Eating it in moderation can promote gastrointestinal peristalsis, but if it is eaten in excess, it may increase the burden on the human stomach, especially for constipation people. Eating yam in excess is easy to aggravate its symptoms. Diabetic patients

Although the sugar content of yam is relatively low, its starch content is relatively high, and starch will be converted into glucose in human body. Excessive eating may lead to high blood sugar level, so diabetic patients should not eat yam excessively to avoid aggravating their condition. Allergic people

Yam contains certain mucus substances, which are allergic to certain extent. People who are allergic to yam should not eat yam, otherwise it will easily induce or aggravate their allergic symptoms, leading to tongue numbness, tight throat and hair, which will pose a threat to human health.