Compared to rice, every 10 grams of sweet potato contains higher levels of carotene, vitamin C, dietary fiber, and potassium. However, other nutrients, especially protein, are not as abundant in sweet potatoes as in rice. Furthermore, many nutrients in sweet potatoes are not comparable to those found in common vegetables and fruits. Therefore, in terms of nutritional value alone, sweet potatoes are not as nutritious as we might imagine.
Nevertheless, some of the benefits of sweet potatoes are indeed not just hype.
First, they help prevent cancer and high blood lipids. The dietary fiber in sweet potatoes can absorb water in the intestines and expand rapidly, thereby increasing stool volume and promoting bowel movements. This helps prevent constipation, promotes the excretion of toxic and harmful substances and cholesterol, and indirectly helps prevent colon cancer and high blood lipids.
Of course, the carotene and vitamin C in sweet potatoes themselves have certain antioxidant and anti-cancer properties.
Second, sweet potatoes can aid in "weight loss" (weight management). There are three reasons for this: ① Sweet potatoes are relatively low in calories. For every 100 grams, the calories are only one-third of that of the same weight of rice. Both fat and carbohydrates are lower than in rice and flour. Therefore, eating an appropriate amount of sweet potatoes until full makes it less likely for calories and fat to exceed limits, achieving the goal of weight management. ② The dietary fiber in sweet potatoes helps promote the excretion of fat and sugar from food, which are the "culprits" of obesity. ③ Sweet potatoes have a low glycemic index. This means that after eating sweet potatoes, the digestion and absorption of sugar are slow, leading to stable blood sugar levels for a longer period after the meal. The eater is less likely to feel hungry and will unconsciously reduce snacking.
Thus, sweet potatoes have effective methods for managing weight. Consequently, sweet potatoes have good effects in preventing and treating metabolic disorders such as diabetes and obesity. Cooked Sweet Potatoes are More Beneficial
Sweet potatoes must be cooked before eating because they contain a large amount of starch, which is wrapped in a tough cell membrane. They are only easily digested and absorbed by the human body when they are thoroughly cooked or steamed. Additionally, during the steaming and cooking process, most of the oxidase in sweet potatoes is destroyed, which reduces gas production and makes the eater less likely to experience gastrointestinal discomfort such as bloating and acid reflux.
Of course, sweet potatoes also have their shortcomings: their protein and fat content is relatively low. This is not a major flaw in itself, but the problem is that they are not "generous." Not only do they lack these nutrients themselves, but their dietary fiber also carries away some important nutrients like protein and calcium from other foods. Therefore, long-term and excessive consumption of sweet potatoes can affect the absorption of certain important nutrients, leading to malnutrition.
From a health perspective, we can make rice, flour, etc., our staple food and consume 80-100 grams of sweet potatoes daily. Sweet potatoes can be eaten with meals or as a snack between meals, such as after breakfast or lunch, which can better help delay the feeling of hunger in the morning or afternoon. The digestive function of the elderly is weaker, and that of infants and children is not fully developed, so they should not eat a large amount of sweet potatoes at once. Pairing Sweet Potatoes with Milk
Since sweet potatoes contain little protein and fat, they are suitable to be eaten with high-quality protein foods such as milk and meat.
There are many varieties of sweet potatoes available on the market, including red-fleshed, purple-fleshed, and pale yellow-fleshed types. Different varieties have certain differences in their content of carotene and phytoactive substances. Red or yellow, or the deeper the color, the higher the content of these components, but the overall difference is not significant. More importantly, the differences in dietary fiber content or other nutrient contents among them are also small. Therefore, current research has not found a clear "champion" among them in terms of preventing constipation and promoting health.