The 80-year-old grandmother Wang has high blood pressure and diabetes, and needs to take long-term medication. Her usual diet is also very light, especially like to eat mixed grains and coarse grains.
Some time ago, relatives in my hometown gave Grandma Wang a large bag of sweet potatoes, and I heard neighbors say that sweet potatoes can reduce sugar and fight cancer, so Grandma Wang eats almost every day, sometimes directly as a meal, and as a result, she eats bloating, abdominal pain, nausea, and vomiting.
After her daughter discovered Grandma Wang's abnormality, she quickly sent her to the hospital for examination.
After receiving the consultation, the doctor found that Grandma Wang had dry skin, wet and cold limbs, chest and abdomen CT showed "small intestine mass possibility, accompanied by small bowel obstruction", blood test results showed "serious infection, abnormal heart and kidney function", and diagnosed as intestinal obstruction and shock.
Fortunately, after surgery, Grandma Wang was out of danger.
In this regard, the doctor explained that the gastrointestinal tract of the elderly is poor, sweet potatoes contain a large amount of tannic acid, and eating too much in an empty stomach will form hard stomach stones, resulting in intestinal cavity blockage. If not intervened in time, the proximal bowel will die, perforate, and in severe cases, lead to death.
01 Sweet potatoes are the "king of anti-cancer", can also lower blood sugar?
From this point of view, sweet potatoes can not be eaten more. However, is it true that Grandma Wang heard that "sweet potatoes can lower sugar and fight cancer"?
In fact, the phrase "sweet potatoes fight cancer" comes from a study conducted by Japanese scientists in 2014, in which researchers investigated the eating habits of Japanese citizens and found that:
Eating vegetables can fight cancer, of which sweet potatoes can play a 95% anti-cancer effect, and cooked sweet potatoes can even inhibit a 98% chance of cancer.
Researchers believe that vitamins, proteins, dietary fiber, amino acids, pectin, etc. in sweet potatoes can protect the activity of human epidermal cells, enhance the activity of cells, and play a role in inhibiting cancer.
However, sweet potatoes are not so magical, and "sweet potatoes fight cancer" is an unscientific statement.
First of all, the study did not carry out human experiments, although the anti-cancer effect of sweet potatoes was indeed found in animal experiments and in vitro experiments, but it does not mean that the same effect can be achieved in humans. Secondly, the experiment uses the extract in the sweet potato, not the sweet potato, the sweet potato extract is not equal to the sweet potato, do not confuse the concept.
In addition, regarding the statement that "eating sweet potatoes can lower blood sugar", Cheng Zhifeng, director of the Department of Endocrinology of the Fourth Affiliated Hospital of Harbin Medical University, explained:
A glycemic index higher than 70 is a high glycemic index food, and the glycemic index of red sweet potatoes is 76.7 after cooking, and the glycemic index is 54 after cooling.
The reason why sweet potatoes reduce sugar is because compared with rice, noodles and other foods, sweet potatoes have a relatively low carbohydrate content and calories, and are rich in dietary fiber and pectin, which can delay the absorption rate of sugar and fat in food.
In short, sweet potatoes can not reduce sugar, but can increase satiety and indirectly reduce sugar intake. Of course, if you eat sweet potatoes and rice, your blood sugar may rise instead of falling.
02Eat sweet potatoes every day, what can the body harvest?
Then again, although eating too many sweet potatoes is not beneficial, the nutritional value of sweet potatoes cannot be ignored. The main component of sweet potatoes is starch, which can be eaten as a staple food.
In addition, the amino acid structure in sweet potatoes is more reasonable, which can complement the protein in rice noodles and improve the utilization rate of protein. The "Dietary Guidelines for Chinese Residents (2022)" suggests that you can consume 50-100g of potato food per day, so what benefits can the body harvest with one sweet potato a day?
1. Weight control
Sweet potatoes are low-fat, low-calorie food, compared with rice, sweet potatoes have lower fat and calorie content, only 0.2 grams of fat per 100 grams of fresh sweet potatoes, producing 99 kcal of heat energy, as a staple food, can enhance satiety, reduce the intake of other foods, to achieve the effect of weight control.
2. Promote intestinal peristalsis
Sweet potatoes are rich in dietary fiber, which can promote digestive tract peristalsis, clean up the digestive tract, shorten the time for toxic substances in food to stay in the intestines, accelerate the excretion of feces, prevent constipation, and reduce the risk of hemorrhoids and bowel cancer.
3. Protect eyesight
Sweet potatoes can also protect vision, and the carotene and vitamin A they contain can maintain normal visual function and protect the eyes.
There are also many types of sweet potatoes, there are sweet potatoes, purple potatoes, white potatoes, etc., there is a saying that purple potatoes are healthier than sweet potatoes, is there a scientific basis?
In fact, sweet potatoes and purple potatoes are low-calorie foods, but purple potatoes contain higher calories than sweet potatoes, purple potatoes have 133kcal/100g of calories, and sweet potatoes have 87kcal/100g.
In addition, both are also high dietary fiber foods, with dietary fiber content as high as 2.5g-3g/100g. The main difference between sweet potatoes and purple potatoes is the different micronutrient content, the content of lutein in sweet potatoes is higher than that in purple potatoes, and the anthocyanin content in purple potatoes is higher than that in sweet potatoes.
So purple sweet potatoes and sweet potatoes are very good, there is no claim that anyone is healthier than whom, and which one to eat mainly depends on personal preference.
03Can eating baked sweet potatoes cause cancer in winter?
The weather is cold, and it is slowly the season to eat roasted sweet potatoes, but many people are worried that baked sweet potatoes will have health risks, and the roasted sweet potatoes sold outside are particularly sweet, is it "added"?
Roasted sweet potatoes are sweeter, and in addition to the variety of sweet potatoes, they are also related to the way they are cooked. In the process of roasting, the water in the sweet potato is constantly lost, the sugar is constantly concentrated, and finally part of the starch will be decomposed into maltose, so it tastes fragrant and sweet.
As for the black hard lumps on the surface of baked sweet potatoes, they are the result of caramel reactions after the sugar in sweet potatoes are concentrated at high temperatures, and are not carcinogens.
Sweet potatoes are a rare nutritious and affordable food, of course, to eat sweet potatoes healthily, these points to remember:
1. Sweet potatoes should be eaten in moderation, not more
Eating too much sweet potatoes will cause flatulence, hiccups, and even intestinal blockages, and it is recommended to eat more than 100-200 grams of sweet potatoes per day. In addition, it is best to replace some staple foods with sweet potatoes, and do not eat sweet potatoes as a staple food.
2. People with bad stomach eat less sweet potatoes
Sweet potatoes also contain more sugar, and excessive sugar intake will increase gastric acid secretion and increase gastrointestinal pressure, so people with a bad stomach and a weak spleen and stomach should eat less.
3. Do not eat moldy sweet potatoes
Sweet potatoes are not recommended to be stored for a long time, easy to mold, produce carcinogens aflatoxin, moldy sweet potatoes should not be eaten, so as not to poison.
Do you like sweet potatoes? Sweet potatoes have many health benefits, but remember to eat them in moderation and don't eat more!
Source: 39 Health Network WeChat