Water-soluble and insoluble dietary fiber: The key choices for scientific weight loss.

When we talk about health and weight loss, we often mention dietary fiber. But what exactly is dietary fiber? Dietary fiber is a complex carbohydrate that the human body cannot digest, and it is widely found in vegetables, fruits, and grains. Unlike simple carbohydrates (sugars and starches) that are quickly absorbed by the body, dietary fiber cannot be broken down by the body, does not provide energy, and therefore does not cause fluctuations in blood sugar levels.

Although seemingly without value, dietary fiber actually plays a very important role. Because it cannot be digested by the body, dietary fiber acts as a "scavenger" in the intestines, helping to eliminate waste from the body and improve constipation. Dietary fiber also slows down the rate of food digestion, helping us control blood sugar, lower blood lipids, maintain intestinal health, and reduce the risk of diabetes, heart disease, and colon cancer. Dietary fiber also helps prolong satiety, reduce appetite, and promote weight loss.

The World Health Organization recommends that adults consume at least 25 grams of dietary fiber per day. The best sources of dietary fiber are natural and delicious foods, such as whole grains, beans, vegetables, nuts, and mushrooms. However, consuming whole grains and beans to obtain dietary fiber can also lead to excessive intake of carbohydrates. Therefore, during weight loss, we should choose foods that are lower in sugar and higher in dietary fiber, such as chia seeds, almonds, dark chocolate, avocados, bean sprouts, seaweed, black fungus, and kelp.

Dietary fiber is divided into two types: insoluble dietary fiber and soluble dietary fiber. Insoluble dietary fiber is what we commonly call roughage; it increases food volume and helps with bowel movements, but it has a rougher texture, such as wheat bran. Soluble dietary fiber dissolves in water and ferments in the large intestine to become prebiotics, providing abundant nutrients for the gut microbiota, promoting intestinal health, and having a better texture.

Many people choose to consume insoluble dietary fiber, which provides more sensory satisfaction, while neglecting the more valuable soluble dietary fiber. In fact, during weight loss, you should consume more water-soluble dietary fiber that is low in sugar. Green leafy vegetables, fruits, mushrooms, and nuts are good sources of water-soluble dietary fiber.