As is well known, sweet potatoes are very nutritious. What's more valuable, however, is that in the recent "ranking" of 20 anti-cancer vegetables released by the Japanese National Cancer Research Center, sweet potatoes took the top spot.
Cancer cells originate from human epithelial cells, and sweet potatoes are rich in starch, carotene, and more than 10 trace elements such as potassium and iron. They can protect the structural integrity of human epithelial cells, inhibit viral activity, block the production of nitrosamines in the gastrointestinal tract, eliminate the toxic effects caused by mercury, cadmium, arsenic, and other toxic substances in food or the environment, and interrupt the carcinogenic process of toxic metals. Sweet potatoes are called by experts the most nutritionally balanced health food.
Moreover, the unique dehydroepiandrosterone (DHEA) in sweet potatoes—a steroid hormone similar to androgen, secreted by the adrenal gland—can both prevent cancer and prolong life.
Roasted sweet potatoes in winter should not be eaten with their skin.
The hot roasted sweet potatoes of the moment are sweet and delicious, and some are roasted until "sugar oil" leaks out. The charred skin of the sweet potato is especially popular, and many people eat it along with the skin.
Experts say that it is best not to eat roasted sweet potatoes with their skin, because the skin contains more alkaloids, and eating too much can cause gastrointestinal discomfort. Especially the skin of sweet potatoes with black spots cannot be eaten, as it can cause poisoning.
Eating sweet potatoes must pay attention to time and method
1. Sweet potatoes should not be eaten raw.
Because the cell membranes of the starch in raw sweet potatoes are not broken down by high temperature, it is difficult to digest in the human body. At the same time, when cooking sweet potatoes, the steaming time should be appropriately extended to destroy the "gasification enzyme" contained in the sweet potatoes, so that discomfort such as bloating, heartburn, belching, nausea, and flatulence will not occur after eating.
2. It is good to eat sweet potatoes with other foods.
If sweet potatoes are eaten with rice and flour, they can also have a complementary effect on protein. If you also eat some pickles or fresh radishes at the same time, it can reduce the production of stomach acid.
3. It is best to eat sweet potatoes at noon.
This is because the calcium contained in sweet potatoes needs to be absorbed by the human body for 4 to 5 hours after eating, and the sunlight in the afternoon can promote the absorption of calcium. In this case, eating sweet potatoes at lunch allows the calcium to be fully absorbed before dinner, without affecting the absorption of calcium from other foods at dinner.