To this day, people's diets are not only about delicious taste but also about nutrition and health. But what you don't know might shock you. People think their diet is already very nutritious, but surprisingly, nutritionists point out that despite the rich nutrients in food, some daily habits unknowingly deplete them completely. So, how exactly are nutrients lost in food? Let's see what nutrition experts have to say: 1. Excessive washing of rice leads to great loss of nutrients
The Chinese attitude towards rice has always been the same: "wash". Washing means rinsing it again and again: at least two or three times, sometimes four or five times, depending on how clean the housewife wants it. Unfortunately, as Dr. Xun tells us, B vitamins start to be lost after washing rice twice. Beyond two washes, various nutrients begin to be lost.
Nutrition experts suggest: do not wash rice too many times; generally, rinsing it twice with clean water is sufficient. Do not rub it vigorously. For rice that has been stored for a long time, it's better to wash it a few more times. The water absorption rate of rice is highest after soaking for two hours, so it's better to soak the rice for two hours before cooking. Soaking rice before cooking not only saves 40% of the time but also results in less loss of Vitamin B5 in the rice.[China Cuisine]
Some people like "lao fan" (捞饭), which is to cook the rice until it's half-done, then scoop it out and steam it, discarding the rice soup. This practice is unscientific. If you make "lao fan", the rice soup should also be consumed because many nutrients are in it. 2. Don't add alkali when cooking porridge, except for cornmeal
When cooking rice, porridge, beans, or stir-frying, it's not advisable to add alkali because it easily accelerates the destruction of Vitamin C and B vitamins. Vitamin B1 and B2 are already sensitive to heat; adding alkali makes them even more sensitive, and they are more easily destroyed at slightly higher temperatures.
The bound niacin in corn is not easily absorbed by the human body. If you add a little baking soda to cornmeal when making corn porridge, steamed cornbread, or corn cakes, the resulting food will not only be excellent in color, aroma, and taste, but the bound niacin will also be easily absorbed and utilized by the body. 3. Cut vegetables less, tear by hand when possible
Vegetables should be washed before cutting, otherwise water-soluble vitamins and minerals will be lost. When cutting vegetables, it's generally not good to cut them too small. Tear them by hand whenever possible and try to use knives less, because iron can accelerate the oxidation of Vitamin C. When stir-frying, use high heat and cook quickly, avoid long stewing, and keep the lid on to prevent water-soluble vitamins from escaping with steam. Try to add as little water as possible when stir-frying. When stewing, add a little vinegar to season and to protect Vitamin C from loss. When making meat dishes, add a little starch to reduce the loss of nutrients and improve the texture. 4. Juice has less nutrition, fresh fruit is better
When fruit is juiced, the pulp and membrane are removed. In this process, Vitamin C is greatly reduced. If the fruit itself doesn't contain much vitamin, like an apple, then in this process, the vitamins are almost completely removed. It is recommended to use a blender to make juice, which can retain the pulp and membrane.
Once bottled juice is opened, it begins to lose its nutritional value, so don't store it in the refrigerator for too long. Aseptic juice made from citrus, grapefruit, pineapple, etc., can retain its nutrients for 7-10 days. Other low-acid juices, like apple and grape, can be stored for a week after opening. If you buy unpasteurized juice, you must drink it within a week, even if it's unopened. 5. Eggs are nutritious, best boiled
In terms of nutrient absorption and digestibility, boiled eggs are 100%, scrambled eggs are 97%, fried eggs are 81.1%, eggs beaten into boiling water or milk are 92.5%, and raw eggs are 30%-50%. Therefore, boiling eggs is the best way to eat them, but you should chew slowly, otherwise it will affect absorption and digestion.
However, for children, steamed egg custard and egg drop soup are the most suitable, because these two methods break down the protein, making it very easy for children to digest and absorb. 6. Long soup cooking time means no "good" nutrition
Cantonese cuisine pays the most attention to soup, which is evident from the fact that they use the same word "liang" (靓) to praise both soup and beautiful women. Cantonese call the process of making soup "bao" (煲), believing that the longer it's cooked, the better, sometimes for half a day. Dr. Xun tells us that this is actually unscientific. Vitamin C, B vitamins, amino acids, and other very nutritious ingredients have a common weakness: they are "afraid" of heat and are lost above 80°C. Therefore, the long, slow cooking of soup will destroy these nutrients, and what evaporates is precisely the essence. 7. Repeated freezing is actually a mistake
All food has a shelf life of up to 3 months. Take fish as an example; studies have shown that stored at -18°C for 3 months, the loss of nutrients in fish is very significant, especially vitamins A and E, with a loss of about 20%-30%. Vegetables and fruits should also be bought and eaten fresh, as their vitamin content decreases with each day of storage. Therefore, eat the food while it's still fresh, don't wait until it has no nutritional value left.
Many housewives thaw a large piece of frozen meat, and then refreeze the leftover cut pieces, thinking this will preserve them for a long time. This is actually a wrong practice. Nutrition experts say that studies have shown that repeatedly frozen fish and meat can lead to nutrient loss and affect taste. In addition, general preservation should be "fast freeze, slow thaw," meaning freeze quickly and thaw slowly. Sometimes, to speed up thawing, people rinse frozen meat with hot water, which is also incorrect.[China Cuisine] 8. Long-term medication requires vitamin supplementation
Medication can also lead to a large loss of nutrients, including steroid drugs for treating asthma and rheumatoid arthritis, drugs for treating epilepsy, and drugs for treating thyroid diseases. When taking these drugs, one should persist in taking calcium supplements and Vitamin D. Anti-epileptic drugs can also interfere with folic acid absorption.
Also, long-term use of antibiotics can lead to the loss of Vitamin B complex and Vitamin K, affecting gastrointestinal function; long-term use of aspirin can easily lead to the loss of Vitamin C; cold medicines and painkillers can reduce the level of Vitamin A in the blood; the progesterone in birth control pills can hinder the function of Vitamin B6 and interfere with folic acid absorption; sulfa drugs and cholesterol-lowering drugs can affect folic acid absorption; diuretics taken by patients with high blood pressure or nephritis, as well as laxatives, can lead to a large loss of calcium, potassium, and vitamins in the body; patients with stomach ulcers or hemorrhagic anemia, and those taking antacids or alkaline drugs, should pay attention to supplementing trace element iron.
Therefore, the above patients should pay attention to supplementing various lost nutrients while taking medication. 9. Mix filling in one direction, don't stir back and forth
When making dumplings, many people squeeze the water out of the dumpling filling, which leads to a large loss of nutrients.
When mixing dumpling filling, you can mix the water from the chopped vegetable filling with the seasoned meat filling, so the nutrients in the vegetable filling won't be lost.
Nutrition experts remind everyone to pay special attention: when mixing meat filling, you should add a small amount of water while stirring the meat filling in one direction. Never stir back and forth. This is because the protein in meat has a spiral structure, and stirring back and forth will destroy it. The hydrophilic groups in the protein absorb water, which makes the texture better and prevents nutrient loss. 10. Blanch spinach before stir-frying for better calcium absorption
Before stir-frying spinach, few people know it should be blanched first. This is because spinach contains a lot of oxalic acid, which combines with calcium in the food to form calcium oxalate, which the human body cannot absorb. This leads to calcium loss. Blanching spinach in boiling water can dissolve over 80% of the oxalic acid, thereby increasing the bioavailability of calcium. 11. Smoking a few cigarettes greatly damages vitamins
"A cigarette after a meal is like being a immortal," but little do you know the price of being an immortal is heavy; it makes the food you eat lose its nutritional value.
Nutrition experts say that smoking 10 cigarettes will cause a loss of 25-100 mg of Vitamin C and a large amount of B vitamins in the body. And some men who smoke at least a pack a day can calculate how many nutrients they lose. It is precisely for this reason that men who smoke often have poor resistance to infection and catch colds and headaches easily. Therefore, Dr. Xun suggests that smoking men should supplement B vitamins and Vitamin C appropriately. 12. Sweating from exercise requires timely hydration
During exercise, due to energy consumption and sweating, a large amount of energy substances is consumed on one hand, and a large amount of nutrients such as sodium, potassium, and carbohydrates is lost on the other. If not replenished in time, it can easily lead to overtraining and difficulty recovering, which will directly affect the fitness results. Therefore, to improve the effectiveness of exercise, one should not only drink sports drinks containing sugar, water, and electrolytes but also promptly supplement special sports nutrition products, especially for those who want to gain muscle or lose fat. 13. Don't boil fresh milk, heat it in a water bath
The heating temperature of milk should not be too high. When heated to 100°C, not only are its color, aroma, and taste reduced, but its nutritional value is also greatly diminished.
So, how to heat milk correctly? When heating milk, it's best not to bring it to a boil. When small bubbles appear all over the surface of the milk, which is about 70°C-80°C, you can cook it for a few more seconds. If using a microwave, don't heat it for too long, as high temperatures will destroy the nutrients in the milk. Generally, once the milk comes to a boil in the pot, you should remove it immediately.
In addition, young mothers should pay attention to the water temperature when preparing formula for their babies. Since the nutritional components of formula are similar to fresh milk, the water temperature should not exceed 60°C. 14. Eating too many eggs and meat leads to iron loss
Many children suffer from iron-deficiency anemia. Iron deficiency in the body affects a child's intelligence, which is related to children eating meat but not vegetables.
It turns out that many mothers believe that egg yolks and lean meat contain the most iron, so they let their children eat a lot of meat but don't pay attention to making them eat vegetables and fruits. Unexpectedly, the children's weight shoots up, but upon checking, they are found to have iron-deficiency anemia.[China Cuisine]
Nutrition experts believe that the iron in egg yolks and lean meat is mostly trivalent iron, which is not easily absorbed by the human body and most of it is excreted. Trivalent iron can only be converted into divalent iron, which can be absorbed by the body, in the presence of Vitamin C and acidic substances. Vegetables and fruits contain the most Vitamin C and acidic substances. Therefore, Dr. Xun reminds parents to let their children eat more vegetables and fruits along with meat. 15. A lot of fish and meat makes the body acidic
Because meat is an acidic food, people who often eat large amounts of fish and meat tend to have an acidic body constitution. When the body's acid-base balance is severely disrupted, the body will use two main alkaline substances—sodium and calcium—to neutralize it. Two experiments have confirmed this: eating a diet containing 80 grams of protein a day leads to a loss of 37 mg of calcium; while eating a diet containing 240 grams of protein a day, plus an additional 1400 mg of calcium supplementation, still results in a loss of 137 mg of calcium. Therefore, experts suggest that daily diet should pay attention to acid-base balance, and when eating a lot of fish and meat, it should be paired with more fresh vegetables and fruits. 16. Overly refined food leads to mineral loss
As people's living standards continue to improve, a variety of foods on the dining table are becoming increasingly refined. However, in this refining process, a large amount of vitamins and minerals are lost. For example, in refined rice and white flour, after multiple processing steps, folic acid is reduced by 90%, Vitamin E is lost by over 90%, Vitamin B5 is lost by 60%, and the content of minerals such as chromium, manganese, iron, cobalt, copper, zinc, and magnesium is reduced by over 70%. As a result, women who often eat refined foods may experience calcium loss, leading to osteoporosis, and a lack of vitamins can also lead to beriberi and constipation. Dr. Xun suggests that the solution is simple: eat more whole grains. 17. Walking immediately after a meal makes it difficult to absorb nutrients
"Walking a hundred steps after a meal" is a habit for many people, but Dr. Xun believes this might cause nutrient loss in the body.
This is because after a meal, a large amount of blood is needed to help the digestive organs function. If you exercise or walk immediately, blood flow to the limbs increases, which relatively reduces blood supply to the gastrointestinal tract, affecting digestive function and hindering food digestion, which in turn affects the body's nutrient absorption. Some people also like to take a bath immediately after a meal, which causes the skin's capillaries to dilate and充血, leading to insufficient blood flow in the digestive system and affecting the digestion and absorption of food.
So, when after a meal is it appropriate to engage in these activities? According to research, the time food stays in the digestive tract is about 5 hours for fat, 2 hours for protein, and 1 hour for carbohydrates. Nutrition experts suggest resting for 30 minutes to 1 hour after a meal before engaging in light activities.