Introduction: The digestion time of food refers to the time it stays in the stomach. Simply speaking in terms of nutrients, starches and sugars have the fastest gastric emptying speed, taking just over an hour; fats have the slowest, requiring over 6 hours; and protein is in the middle, taking about 3 hours. Moreover, we can also roughly distinguish the speed of food digestion based on the type of food.
Comprehensive Food Digestion Time Table
Fruits: 30 minutes — 1 hour
Watery fruits (like watermelon) require the shortest digestion time, while bananas take the longest. If you feel hungry between meals and want a fruit to tide you over, bananas are a great choice. Watermelon will quickly provide energy and raise blood sugar, making it especially unsuitable for diabetics.
Vegetables: 45 minutes — 2 hours
Watery vegetables (like winter melon) take the least time to digest, followed by solanaceous vegetables (like tomatoes, eggplants), then leafy vegetables (like spinach, bok choy), and cruciferous vegetables (like broccoli). Root and stem vegetables (like sweet potatoes, taro) have the longest digestion time. Therefore, root and stem vegetables can be used as staple foods. People with poor digestion should eat less of cruciferous vegetables like broccoli; if they do, they must be cooked until very soft.
Grains: 1.5 hours — 3 hours
Liquid or semi-liquid grain foods (like congee) have a shorter digestion time. Fermented foods without added fat (like steamed buns, fat-free bread) are also relatively easy to digest. They have the highest digestion rate in the body, up to 98%. Therefore, for people with weak gastrointestinal systems, congee, steamed buns, etc., are good choices. However, if fat is added, such as in fried steamed buns or fried rice, they become hard to digest.
Proteins: 1.5 hours — 4 hours
Liquid protein foods like milk and soy milk are relatively easy to digest, while it takes 4 hours or more to fully digest protein-rich meats like beef and chicken.
Fats: 2 hours — 4 hours
The digestibility of fats is related to the content of their low-chain fatty acids and unsaturated fatty acids. The higher the content of these fatty acids, the easier it is to digest. Therefore, vegetable oils are easier to digest than animal fats. Consuming fats together with grains or protein foods will prolong the digestion time of the latter. Eating greasy staple foods and dishes will place a heavy burden on the stomach and intestines.
New Dieting Concepts: Choose the Right Foods for Better Health
1. White rice digests quickly; whole grains keep you full
Staple foods are mainly starch. But seemingly similar starches are digested and absorbed very differently in the human body. Research has found that foods made from refined rice and white flour, such as rice, steamed buns, noodles, and bread, are digested and absorbed extremely quickly, with a speed almost comparable to that of white sugar. Among them, white congee, the fastest to digest, is completely digested in only 90-120 minutes.
The digestion and absorption of starch in whole grains and beans are significantly slower because their dietary fiber hinders the digestion and absorption of starch. Therefore, nutrition classifies starch into "rapidly digestible starch," "slowly digestible starch," and "resistant starch." Starch that is digested too quickly can, on one hand, promote fat synthesis in the body, easily making people feel hungry again, leading to uncontrollable snacking or overeating at the next meal, which can result in obesity. On the other hand, it can significantly raise post-meal blood sugar.
Whole grains like purple rice, brown rice, and oats, as well as various beans like red beans, black beans, and soybeans, contain more slowly digestible starch. They should be combined with foods containing "rapidly digestible starch," such as refined rice and white flour, to form staple foods. This way, the feeling of fullness lasts longer, effectively suppressing appetite and controlling weight.
2. Red meat is the hardest to digest
Compared to other foods, meat is inherently slow to digest, requiring about 4-6 hours. Therefore, if you eat a lot of meat in one meal, you won't feel hungry for a long time. Roughly speaking, the higher the fat content in the meat, the longer the digestion time. Thus, fish and shellfish digest the quickest, poultry like chicken and duck are in the middle, and red meats like pork, beef, and lamb digest more slowly.
3. Watery vegetables digest quickly, root and stem vegetables digest slowly
The digestion time for vegetables is about 1-2 hours. Among them, watery vegetables like winter melon, cucumber, and zucchini digest the fastest; next are solanaceous vegetables like tomatoes and eggplants, as well as fungi. Leafy, bamboo shoot, and cruciferous vegetables are slower to digest because they contain a lot of cellulose. Root and stem vegetables like sweet potatoes, potatoes, and corn contain a lot of slowly digestible starch, so their digestion time is longer, and they can replace some staple foods. In terms of quantity, about two portions of root and stem vegetables can replace one portion of rice or flour.
Vegetables have many benefits for the body, but often we use wrong cooking methods, such as using too much oil when stir-frying, putting celery or bean sprouts under the thick oily broth of boiled fish, or dipping leafy vegetables in spicy hot pot. Due to the oil-absorbing nature of vegetables, these cooking methods turn originally easy-to-digest, low-fat, low-calorie vegetables into hard-to-digest, high-fat foods. The best ways to eat vegetables are to steam, boil, or eat them cold, or to eat them raw. If you prefer stir-frying, use less oil and stir-fry quickly.