🌿 Folk Prescriptions

Global dietary guidelines now prioritize increasing carbohydrate intake and reducing fat intake. The Chinese Nutrition Society emphasizes in "Dietary Guidelines for Chinese Residents" that diets should be diverse and primarily based on grains. Nutritionists unanimously agree that adults should consume at least 55% of their total energy from carbohydrates, including diabetics. The fundamental pathophysiology of diabetes involves absolute or relative insulin deficiency, leading to metabolic disorders primarily involving carbohydrates. The traditional approach of controlling blood glucose by restricting carbohydrate intake often left diabetic patients in a semi-starved state, which was actually detrimental to treatment. How can patients obtain sufficient carbohydrates without raising blood glucose levels? At the recent symposium on "Glycemic Index of Foods and Human Health," Chinese and foreign nutritionists reported the latest research findings. Different carbohydrate foods vary in quality. Research shows that even when carbohydrate content is identical, different foods produce distinct blood glucose responses. For example, after consuming 50 grams of carbohydrates, two hours later the glycemic index (GI) values were: rice 88, steamed pancake 79.6, cornmeal porridge 50.9, tofu 23.7, watermelon 72, cherry 22, fructose 23, maltose 105. This completely overturns the long-standing classic theory of food equivalence used in diabetes dietary guidance—e.g., 25 grams of rice = 25 grams of cornmeal = 25 grams of fried dough stick = 25 grams of mung beans; 25 grams of fatty pork = 60 grams of egg = 80 grams of carp. The GI value represents the ratio of a food’s blood glucose-raising effect to that of a standard food (usually glucose). Higher GI values indicate stronger blood glucose elevation effects. Why do foods with identical carbohydrate content cause entirely different blood glucose responses? This is because different carbohydrate foods are digested and absorbed at varying rates in the gastrointestinal tract, influenced by the structure and type of carbohydrates themselves. Natural starches are divided into amylopectin and amylose. The higher the amylopectin content and lower the amylose content, the faster the digestion and absorption, resulting in higher GI values. Glucose and fructose also differ significantly in GI values due to their types. Additionally, processing methods—including particle size, texture, doneness, consistency, and time, temperature, pressure—all affect GI. In short, foods that are easier to digest and absorb have higher GI values. The discovery of resistant starch reveals the mystery behind GI. Researchers found a special type of starch called "resistant starch," present in partially cooked or unground grains, raw potatoes, bananas, and retrograded or aged starches. Resistant starch is not absorbed in the small intestine but ferments in the large intestine. Its absorption rate is about 40%, thus lowering GI. The amount of resistant starch varies with food properties: raw potatoes contain 75% resistant starch, while freshly boiled potatoes contain only 3%, but this increases to 12% after cooling. Due to its health benefits, resistant starch has been extensively studied and developed by scientists. Through special processing, resistant starch content in flour can be increased to 38%. Currently, Western diets typically contain about 10% resistant starch. Dietary fiber and protein help lower blood glucose. Humans cannot rely on a single food source. Nutritional studies show that different dietary components significantly influence GI in mixed meals. Experiments revealed that consuming 50 grams of carbohydrates resulted in the following GI values: pure white rice 83.2, rice + garlic shoots (containing 2.2 grams of dietary fiber) 57.9, plain steamed bun 80.1, steamed bun + braised beef (containing 51 grams of protein) 49.4. This demonstrates the significant impact of dietary fiber and protein on food GI. Experts explain that when dietary fiber is consumed with carbohydrates, the plant cell walls—mainly composed of hemicellulose and cellulose—become more intact and rigid, thereby inhibiting carbohydrate digestion and absorption, reducing postprandial blood glucose and insulin responses. Consuming a certain amount of protein along with carbohydrates promotes insulin secretion, helping lower blood glucose levels. The concept of GI allows diabetic patients to enjoy a wider range of food choices, enabling them to confidently select fruits, consume more legumes and high-fiber foods, eat coarser or less processed grains, and avoid high-GI grains and fermented products—thus satisfying taste preferences while effectively managing blood glucose levels.<Diabetes>