In recent years, many young women, in pursuit of a slim figure, have eaten only vegetables and fruits for three meals a day, viewing staple foods like rice and steamed buns as the enemy, because they believe that "eating staple foods easily leads to weight gain."
Over the past 20 years, the consumption of staple foods by both urban and rural residents in China has shown a clear downward trend. In 2002, the consumption of grain-based foods by urban and rural residents decreased by 21% and 10% respectively compared to 1982 and 1992. In fact, this is a misconception, and the habit of eating only vegetables and no rice is detrimental to health.
Staple foods such as rice and flour are rich in starch and a certain amount of dietary fiber, belonging to the category of complex carbohydrates. Carbohydrates are the most economical and primary source of energy for humans, an essential nutrient that the body cannot do without. After being consumed, they are broken down into glucose in the body to release energy. Glucose is the only usable energy source for brain tissue and red blood cells, and it is also the main energy source for heart and muscle activities. Therefore, a diet that excludes staple foods and relies only on vegetables, fruits, and milk can easily lead to slow thinking, memory decline, and reduced work efficiency. Over time, it can result in a weakened immune system and malnutrition.
Eating more vegetables is not a bad thing, but many vegetables are stir-fried with excessive cooking oil, with some dishes seemingly swimming in oil. Consuming this way can easily lead to high blood pressure, cardiovascular diseases, and obesity. Some people strictly limit their intake of staple foods but consume 2-3 eggs and 250-500 grams of beef daily. In reality, they may not realize that beef, pork, and eggs are all rich in protein and fat. Both protein and fat can be converted into blood sugar through the process of gluconeogenesis. Excessive daily intake of these not only leads to weight gain but also increases the incidence of high blood pressure, obesity, hyperlipidemia, diabetes, and cardiovascular and cerebrovascular diseases.
Moreover, can a diet of only vegetables and no staple foods really help with weight loss? Not necessarily. Besides genetic factors, obesity is generally caused by overeating and a lack of physical activity, and it has no direct causal relationship with eating staple foods. People who eat less or almost no staple foods are not necessarily slim and healthy. For example, the "Atkins" low-carbohydrate diet, which was popular in the United States a few years ago, had noticeable side effects such as bad breath, diarrhea, fatigue, and muscle cramps. Vegetables and fruits are rich in water and vitamins, and contain phytochemicals such as organic sulfides, flavonoids, and plant polysaccharides, which have multiple physiological functions like antioxidant properties, immune regulation, tumor suppression, and anti-aging. This is why they are favorites among beauty-conscious women and those trying to lose weight.
However, the human body requires more than 40 different essential nutrients, and the required amounts for each nutrient vary. Therefore, we advocate for a balanced diet, where the proportions of various nutrients should suit the body's physiological needs.
We should follow the "Chinese Residents' Dietary Guidelines" formulated by the Chinese Nutrition Society in 2007, which recommends a daily intake of 250-400 grams of grains (including tubers and miscellaneous beans). It is important to have a mix of coarse and fine grains; in addition to white rice and white flour, one can include a moderate amount of coarse grains daily to add variety. It is recommended to consume 300-500 grams of vegetables daily, with dark-colored vegetables accounting for about half, and 200-400 grams or more of fruit, with the amount varying by individual.