Looking at this green juice, I feel cool and refreshing, delicious!
Green juice
However, the effect of green juice circulating on the Internet is much more magical than cooling and relieving summer heat:
First of all, it is nutritious, rich in a variety of protein and minerals;
Second, chlorophyll, active enzymes and other components can purify blood and eliminate toxicity in human body;
Third, it can adjust the pH of human body.
Are these statements reliable?
Let's start today's walk into science and see what the green juice "fairy water" is.
There is no great benefit in supplementing nutrition.
Green juice originally refers to the juice squeezed from the tender leaves of barley, and later refers to the juice squeezed from the tender leaves of wheat. Up to now, the juices of many plants such as green tea and Chinese cabbage can be called green juice.
As a beverage, the main component of green juice is water, which is beyond doubt. Except water, the composition of green juice is directly related to the selected raw materials.
What is shocking is the scenery, not the efficacy?
Taking the most common tender leaves of barley and wheat as examples, in 1996, the Institute of Rice and Wheat of Fujian Academy of Agricultural Sciences selected You Min No.3 barley at seedling stage, pre-heading stage, pre-filling stage and mature stage for nutritional determination. The results showed that the amino acid content of barley was the highest at seedling stage, and then with the growth and development of barley, the amino acid content of wheat plants gradually decreased. However, this study did not compare protein between barley and other foods.
20 1 1 Institute of Health and Environmental Medicine of Tianjin Academy of Military Medical Sciences studies wheat seedlings. The protein content of wheat seedlings is 25. 16%, and the crude fiber content is 22.3 1%. In terms of minerals, one kilogram of wheat seedlings contains potassium 16500 mg and potassium 43500 mg. 2
This makes me dizzy. How should I interpret these figures?
The protein content of eggs is 12.6%, and that of soybeans is 36.49%. In other words, the protein content of wheat straw is better than that of eggs and much worse than that of soybeans. Other aspects are similar. One kilogram of soybean contains potassium 17970 mg and zinc 48.9 mg, both higher than wheat straw. Judging from the data found so far, wheat grass is slightly better only in terms of calcium content.
? In short, there is nothing particularly magical.
In addition to the content, the nutritional value of a food should also consider the absorption and utilization efficiency. The absorption rate of eggs and bean products is very high, and eggs reach an astonishing 92%. 3. The data of green juice has not been found, and it is doubtful for the time being; In order to pursue the taste, most green juice drinks have been filtered many times. How much crude fiber can be left in them?
The crude fiber has been filtered out.
There is no basis for expelling human toxins.
There are many similarities in molecular structure between chlorophyll and hemoglobin in human body. But this does not mean that after you drink the green juice, chlorophyll will directly enter the blood and replace the function of hemoglobin.
Chlorophyll, or various active enzymes in food, must first pass through the digestive system after being eaten by people, and be decomposed into small biological molecules by various digestive enzymes in the gastrointestinal tract? It is these small molecules that are absorbed by the human body and are also needed by metabolism.
Chlorophyll is mainly converted into pheophytin in human body, and the absorption rate of pheophytin in human body is extremely low, less than 5%; And active enzymes, in the gastrointestinal tract, they are protein, which is no different from protein in other foods, and will all become amino acids under the action of digestive juice.
As for adjusting the pH of human body, that is an old saying.
The metabolism of human body needs the participation of various organelles and protein, and these structures and substances are very sensitive to the change of pH value. Therefore, human beings have evolved a mature and effective acid-base regulation system to maintain the stability of the internal environment.
In other words, if a person is healthy and has a normal diet, his blood pH will be between 7.35 and 7.45 no matter what he eats. If a person had a problem with the pH of body fluids, such as acidosis, he would have gone to the hospital to lie down. How much green juice is useless?
The more magical the rumor, the less you have to believe it.
Other "magical effects" of green juice are either the lack of conclusive experimental data. For example, in 2004, an Indian paper claimed that the demand for blood transfusion of thalassemia patients decreased by 5% after eating green juice without a control group. Or it has been refuted by professional organizations. For example, the American Cancer Society believes that there is no evidence that wheat seedling juice is beneficial to the human body. four
Why does Japan admire green juice?
According to the dietary standards formulated by the Japanese Ministry of Health, Labor and Welfare, it is recommended that adults consume an average of 350g of vegetables every day. However, due to various reasons, the report of "200 1 National Health and Nutrition Survey" shows that Japanese people's vegetable intake is obviously insufficient, especially for young people aged 20-29, below 240 g.
In this case, drinking green juice may make up for the lack of daily diet and achieve a balanced nutrition.
On the other hand, if your daily diet is balanced, then green juice is completely unnecessary and won't have any magical effect. What's more, it's not cheap.
Truth: You can drink green juice as a drink if you like, but don't expect any magical effect.
?
refer to
1 Zhang Qiuying, Zhang Shaonan. Preliminary study on wheat straw nutrition [J]. Fujian Rice and Wheat Science and Technology, 1996, 14 (3): 9- 13.
2, Li Peibing, Jin Hong, et al. Analysis of nutritional components of wheat straw [J]. Journal of Nutrition, 20 1 1, 33(3): 327-328.
3. China nutritionist training materials [M]. People's Health Publishing House, 2005.
4 Bian Huawei. The health lie of wheat straw juice [J]. Particularly healthy, 2015 (11): 80-81.
Wheat grass and unintentional clouds, untimely arrival, scientific squirrel society, 20 13.
6. Ministry of Health and Welfare. National Health-The 20-year National Health Report of the Ministry of Health and Welfare is in Ping -[J] .20 1 1.
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Author: Zhao Yanchang