In fact, it's not that there is a problem with our balanced diet itself, but that we still have some "nutritional dead ends" that have not been handled well:
In this article, I will focus on explaining the principle of these "nutritional dead corners" and how to avoid them.
Theoretically, except for vitamin D, which is mainly synthesized by skin cells, other vitamins and minerals can be obtained from a balanced diet. However, the cruel reality is that few people can really maintain a balanced diet for a long time, so the following vitamin and mineral deficiencies have emerged:
According to a report in China Disease Prevention and Control, calcium, iron, vitamins A and D are the most easily deficient nutrients in China at present.
Why do people in China generally lack these nutrients? The reason is eating habits. Yes, even a balanced diet can't escape the constraints of habits and regions. So why are the nutrients that are easy to be lacking in every country and nation different? Because some specific eating habits will lead us to lack certain nutrients.
The soil itself lacks nutrients.
For example, in some areas of northern China, the land is seriously deficient in selenium. Therefore, "Kaschin-Beck disease" is very popular in the local area. Even if local residents have achieved a very balanced and high-quality diet, they can't escape the plight of selenium deficiency. Because the soil is hard, water and plants are short of selenium, so we can only make up for it by buying selenium supplements.
Folic acid deficiency caused by poor diet quality
Folic acid is not a patent for pregnant women. But everyone should take enough nutrients, because folic acid involves very important physiological functions in the body: one is the metabolism of homocysteine, and the other is the necessity in the process of making red blood cells. Folic acid is widely found in many foods, especially green leafy vegetables. Folic acid also has a very special property: the absorption efficiency in the form of supplements is higher than that of food sources!
But folic acid is afraid of light and heat, so many people in China will lose folic acid when cooking. In addition, people in China generally have insufficient intake of coarse grains, and folic acid in whole grains has been lost. So the problem of insufficient intake is still very worrying.
Canada, Australia, Mexico and Chile followed the example of the United States and promoted folic acid fortification. For example, all bread sold in Australia will be supplemented with vitamin B 1 and folic acid to make up for the deficiency after the whole grain is converted into flour and rice.
Although there is no such measure in China at present, fortunately, our intake of liver and green leafy vegetables is still relatively high. Therefore, to get enough folic acid, please remember the following formula:
Half a catty of green leafy vegetables per day +65438+ 0-2 times per week+mixed bean rice per day+extra folic acid supplementation for elderly pregnant women = folic acid supplementation without dead ends.
Lack of dairy products and calcium deficiency caused by insufficient sunshine
Calcium deficiency has always been a very big nutritional problem in China. The reasons mainly come from two aspects: on the one hand, the price of dairy products eaten by China people is relatively expensive, so the overall consumption is low; The second aspect is the low quality of domestic dairy products. For example, the common dairy products are only milk and yogurt with high sugar content, while foods rich in calcium such as cheese have low permeability.
Dairy products are the best source of calcium in daily diet, most of which exists in a "free state", and calcium needs the assistance of phosphorus in the metabolic process. The ratio of calcium to phosphorus in milk is 1: 1 (slightly more phosphorus), which is very beneficial for the body to absorb.
In addition to the most golden dairy products, other foods with high calcium content are generally beans, seeds (such as sesame seeds) and fish (sardines, etc.). ) you can eat with bones and dark green vegetables. However, the ratio of calcium to phosphorus in these foods is poor, or the form of calcium is not easy to absorb, or it is more expensive and more difficult to obtain than dairy products. In a word, they are not as simple as drinking milk every day.
There is a lack of sunshine at high latitudes.
Another reason for calcium deficiency is the poor utilization rate of calcium, which is caused by the lack of vitamin D, and the dietary source of vitamin D is very, very limited, and most of it needs to be synthesized by skin itself through sun exposure. Therefore, people who do not bask in the sun for a long time are indeed high-risk groups of calcium deficiency. At this time, they either go out or eat vitamin D fortified foods or supplements.
Single staple food: insufficient coarse grains corresponds to vitamin B deficiency.
Vitamin B contains many kinds of water-soluble vitamins. Because the body can't store them for a long time, it must be supplemented from food every day. The most abundant source of vitamin B family is usually whole grains, especially vitamin B 1 and folic acid.
As the staple food of urban people, white bread and white rice/noodles are all made of grains with wheat bran removed, so the vitamin B family will be lost a lot, which is why in some foreign countries (such as Australia), the health department will force all bread and breakfast cereals that are not whole grain products to be artificially added with vitamin B 1 (thiamine) and folic acid, and iodized salt; Just to block this nutritional corner.
At present, there is no such law in China, but there are similar problems. My suggestion is to replace half of your staple food with whole grains (especially breakfast cereals need to be fortified). Eating vitamin B dietary supplements is also an effective method.
The color of vegetables is single: vegetables that are not dark green and red and yellow are corresponding to the lack of vitamin A.
The sources of vitamin A in food can be divided into two categories: animal vitamin A and plant carotenoids. Animal origin usually comes from the liver, which is not common in the current diet. Plant resources are not only abundant, but also there is no problem of excessive consumption (vitamin A poisoning).
But because most people can't eat carrots, red bell peppers, broccoli, mangoes, cantaloupes and other vegetables every day; On the contrary, I often eat light-colored vegetables such as white gourd and Chinese cabbage, so even if there are enough vegetables on the surface, the nutritional density can't meet the requirements. Eating enough vegetables is an obstacle for many people, and eating enough high-quality and colorful vegetables is even more difficult.
Lack of seafood: lack of iodine, zinc, selenium and omega-3 fatty acids.
Seafood is very regional, and the price is high, and the cooking requirements are not low. Therefore, the lack of seafood can easily lead to the intake of very rich micronutrients in several seafood.
Although meat, nuts, mushrooms and other foods also contain zinc and selenium, they are generally not as rich as seafood. As for omega-3 fatty acids, except deep-sea fish, which can provide the most direct DHA and EPA, only flaxseed and perilla seed oil can provide a small amount of a- linolenic acid, which is an essential fatty acid with low conversion rate, so the lack of seafood in the diet is a serious injury to many people's diet.
Eat less red meat: iron deficiency (especially pregnant women)
Eating less red meat is not a dietary defect. Now epidemiological studies have very reliable evidence that eating too much red meat will bring health risks, such as an increase in the incidence of intestinal cancer. Therefore, we need to limit red meat in our diet, rather than completely rejecting it.
However, even if red meat is eaten reasonably, it is difficult for women from adolescence to premenopausal to achieve the recommended daily iron intake of 15- 18 mg, or even 27 mg for pregnant women. Therefore, in addition to the right amount of red meat, we should eat more iron-rich dark green vegetables, beans, nuts, dried fruits (sugar-free is the best) and whole grains.
Because these irons are "non-heme irons", the absorption rate is limited, so try to eat as much as possible. For pregnant women, eating like this may not be able to fill the iron gap caused by the 40% increase in blood volume. Therefore, if ferritin is found to be seriously reduced in physical examination, the use of iron dietary supplements will be a sharp weapon to avoid anemia during pregnancy.
Vitamin K2 deficiency caused by intestinal flora imbalance
K2 is a subtype of vitamin K, and K 1 is called menadione chlorophyllin, which mainly exists in green leafy vegetables and is easy to supplement. K2, called methylnaphthoquinone, is metabolized and synthesized by human intestinal flora, and its food sources are mainly dairy products and fermented foods (such as natto). The main function of K 1 is related to blood coagulation, and it is also a vitamin that babies need to be injected artificially at birth. The main function of K2 is to mobilize blood calcium and vitamin D to form bone calcium, so it has two major benefits:
1. First, bone calcium was supplemented, which was "increasing savings" when young, and "slowly eating old money" for middle-aged and elderly people.
2. Secondly, it is necessary to avoid the accumulation of hypercalcemia on the arterial wall in time to form terrible plaques and maintain cardiovascular health.
Therefore, as you can see, although vitamin K2 is not well-known, it is highly dependent on health. However, if the intestinal condition is poor and K2 deficiency occurs, it is likely to affect the absorption of calcium, and then affect the bone mineral density. This also explains why many people eat calcium supplements and shrimp skin milk every day, but they are still osteoporosis.
In fact, because it mainly depends on the intestinal flora, you can eat less (cheese and natto are not the foods that people in China often eat).
So once the intestinal flora becomes unhealthy (such as long-term use of antibiotics, poor diet diversity, lack of prebiotics, and intestinal flora imbalance caused by aging itself); We are almost in an unconscious state of helplessness.
So let's face it, if a balanced diet is really difficult for you, I suggest you go to the hospital for a nutritional test, and you can roughly check the lack of common vitamins and minerals through blood tests. Then, in view of these deficiencies, the diet should be improved first, and then vitamin and mineral supplements should be used to make up for this nutritional gap.
Because long-term nutritional deficiency is not only harmful to health, but also has a negative impact on the metabolism of three energy-supplying nutrients, the normal repair of cells and the delay of aging, which is related to chronic diseases such as diabetes, cardiovascular diseases and cancer.
Believe me, spending more energy and time to maintain your health will avoid some economic and life losses caused by diet, which is a huge cost-effective and time-limited investment.