Source: Science Popularization China
In recent years, "health" has become a new favorite of social topics.
In the office, everyone was holding the insulation cup to soak wolfberry to share their own health secrets, and even brushed the mobile phone to see the health prompts forward to the favorite person.
For example, "milk contains hormones, which can cause cancer", "sea fish is more nutritious than freshwater fish", "eating black sesame pills can prevent hair loss", "the more acidic fruits, the higher the vitamin C content", "the more chocolate has white cream, it is a deterioration."" Foods without food additives are healthier, buy zero adding if you want to buy … Are these health statements reliable?
Milk contain hormones and can cause cancer?
Milk is one of the most effective foods for calcium.
However, there is a saying on the Internet that there are hormone IGF-1 in milk, and drinking will cause cancer.is this real?
The full name of IGF-1 is "insulin-like growth factor 1". It is not a harmful substance to add, but a hormone-like protein secreted by the cow itself.
In addition to dairy cows, the human body will also produce this hormone. Adults have a daily generated amount of 10 million nakes, while the IGF -1 content in the milk on the market is only about 2.45 ng/ml, which is compared with the amount in the human body.Compare, it is simply not worried.
The Evaluation of Food Additives (JECFA) of the Food and Drug Administration (FDA) and the World Health Organization and the United Nations Food and Agriculture Organization all believes that there is no evidence that IGF-1 will cause cancer.
Judging from institutions that specialize in cancer around the world, normal drinking milk may reduce certain cancer risks.
For example, expert reports jointly released by the World Cancer Research Foundation (WCRF) and the American Institute of Cancer (AICR) in 2017 evaluated diet, nutrition, physical activity and cancer risks.The research conclusion is that dairy intake can reduce the risk of colorectal cancer.
The British Cancer Research Center believes that edible dairy products can reduce the risk of bowel cancer.In my country’s latest "Consensus on Evidence of Food and Health Science", it is also clearly mentioned:
During the research of milk and its products, it has nothing to do with the risk of the incidence of prostate cancer; low -fat milk and their products can reduce the risk of breast cancer, and their whole milk and their products have nothing to do with the risk of breast cancer.
my country’s dietary guidelines recommend drinking 300 grams to 500 grams a day.
But now we drink less than 50 grams of milk every day.Worried about drinking milk to cause cancer, it is really superfluous.
Can eating black sesame pills prevent hair loss?
The folk has always said that eating black food such as black sesame and black beans can make the hair black, and it can also gradually reverse the white hair.
The merchant also took the opportunity to launch the "black sesame pills", saying that it can prevent and treat hair loss, and has been loved by many people with hair loss, hair loss, baldness, and hairline.Can eating black sesame pills really prevent hair loss?
In fact, black sesame can not prevent hair loss, and it may make you gain weight.
The reason why everyone thinks that black sesame, black beans and other black foods are good for the health of hair. It is mainly because it is black, and we always have the traditional culture of "replenishing black with black".
Black sesame and black beans are rich in nutrients and trace elements. If it is white hair caused by protein, B vitamins, and mineral elements, eating black sesame and black beans may have some benefits for hair.
However, melanin in black foods such as black sesame and black beans does not make hair black.Because the source of melanin in the hair is melanocytes, it uses tyrosine in the body to transform to generate melanin.
The melanin in black sesame and black beans is mainly polyphenol pigments, which cannot be directly converted into pigments on the hair.
Moreover, some black sesame pills will add a lot of sugar to season. The fat content of the black sesame itself is also very high, which means that there are many black sesame pills and a lot of oil. If you eat moreEssence
Therefore, don’t be superstitious about black food. I really want to eat black sesame pills. When buying, pay attention to choosing less sugar products.
The more sour fruits, the higher the content of the vitamin C?
Fruits are rich in vitamin C, but what fruit vitamin C has higher content. Many people think that the more sour fruits and VCs, the most typical, the most typical is lemon.
So, the more sour fruits, the more vitamin C content is really?
The reason why someone will have such an impression is mainly because the taste of vitamin C itself is indeed sour. Vitamin C also has a name "Condorbic acid". If you have tasted vitamin C tablets without sugar, you should have experienced the sour tasteEssence
There are indeed some fruits that taste more sour, including vitamin C very high, such as sea buckthorn, which contains 204 mg of vitamin C per 100 grams.
However, the taste of fruits will also be affected by the types and contents of the sugar and organic acids in them, and it has no corresponding relationship with vitamin C content.
For example, everyone often thinks that it is sour -lemon, only 22mg of vitamin C per 100 grams;
Another example is orange, only 33mg of vitamin C per 100 grams. Among these sour legend, "the fruit of high vitamin C", the VC content is not even as good as the Chinese cabbage (47mg/100g).
In fact, a large part of the sour taste in fruits is derived from organic acids, such as apple acid, citric acid, and alcoholic acid.
Organic acid is the intermediate product of the energy metabolism of fruits. The types and composition ratio of organic acids in different fruits are different.
For example, citrus fruits (lemon, orange, orange, etc.) mainly contain citric acid, and berries (such as grapes, etc.) are mainly alcoholic acid. They usually have a large content in immature fruits.The acid will be transformed into sugar, and it will not be so sour.
In short, the sourness of the fruit is not directly related to the amount of vitamin C. There is no need to wrong itself for "nutrition" at all!
Is chocolate white frost? Is it deteriorated?
Did you encounter a layer of "white frost" on the surface when you eat chocolate?Some people say that chocolate "white frost" is deteriorated and can not be eaten anymore.is this real?
In fact, this statement is not accurate.
There are usually two types of chocolate -frost and frost.They are caused by changes in the ambient temperature when storing chocolate.
For example, "frosting", as the name suggests, its main component is sugar.It is often caused by a sharp increase in ambient temperature in a short period of time.
For example, getting the chocolate refrigerated in the refrigerator directly to the room temperature, it is more likely to occur.
In addition, if chocolate is placed in a more humid environment, small droplets will also appear on the surface to produce frosting.
The main ingredient of frosting is fat, which is inseparable from cocoa butter in chocolate.
Cocoa is chocolate, especially the characteristics of high -quality chocolate. It naturally has a strong flavor and seductive luster, which is also the reason for people.
But cocoa butter is very sensitive to temperature.Save chocolate in an environment above 22 ° C for a long time, and the part of the cocoa but also melts and seeps to the surface of the chocolate.
When the temperature decreases, the oil will regain the surface of the chocolate surface, showing a white spots, and it looks like a layer of white frost.
So, can the chocolate of "White Frost" be eaten?
In fact, Qi Cream is mainly due to physical changes caused by temperature changes. Although it has a certain impact on the appearance and taste of chocolate, it does not affect food safety.
If the taste is okay, it is okay to eat; but if it becomes not delicious, then throw it away.
After all, eating chocolate is not just for deliciousness!
Sea fish is more nutritious and safer than freshwater fish?
Many people feel that sea fish live in the blue sea. The environment is better, less polluted, and the DHA content is higher, safer and healthier.is this real?
First of all, everyone must know a reality: In today’s globalization, marine fish will also be polluted by the environment, and Japan will discharge nuclear sewage in the sea.
A common pollution factors in fish are heavy metals.
For example, there are research on 10 kinds of fish arsenic such as heavy metal arsenic in the Beijing market, and it is found that the heavy metal content in seawater fish is higher than freshwater fish.
Studies in Shanghai also found that the content of heavy metal cadmium in seawater is higher than freshwater fish.
Another common harmful substance of fish is persistent organic pollutants.
Some studies have evaluated the pollution level of polymodiacne (PBDES) in the commercial market in Shenzhen and found that the content of seafish is higher than freshwater fish.
The concentration and biological validity assessment of polychromic benzene (PCBS) in commercial foods in Shanghai also found that the concentration level of PCBS in seafish is higher than freshwater fish.
The situation in the United States is not very optimistic.For example, research at Duke University found that the methyl -based mercury in the deep sea was more difficult to be broken down in the environment due to the combination of the molecules of salt (sodium chloride), and it was even more harmful to health.
In fact, health institutions of various countries remind you not to eat high mercury fish, including sharks, flags, catfish, and square fish. These fish are sea fish.
Secondly, the DHA of freshwater fish is not necessarily less than sea fish.
There are 4 kinds of freshwater fish (black fish, Baotou fish, catfish, cinnamon fish) and 6 kinds of seawater fish (catfish, autumn saury, rainbow catfish, cod cod, small fish).The content of unsaturated fatty acids is not lower than seafish.
There are also 9 types of commercially available seawater and bass, bass, catfish, Chinese balm, catfish, Luofei fish, carp and grass carp 5 commercially available seawain and bass, catfish, Chinese balm, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, catfish, Luofei fish, Luofei fish, Luofei fish, martial arts, carp and grass carp.Sell freshwater fish;
It mainly analyzes the content of EPA and DHA in fish and visceral fat. It is found that the content of EPA and DHA in freshwater fish will not be lower than deep -sea fish, and the highest content is even freshwater fish bass.
In fact, whether it is seawater or freshwater fish, their nutrition is not much different. If conditions permit, they are worthy of eating healthy ingredients.
Food without food additives is healthier?
When it comes to food additives, many people now think that they are "technology and hard work", and many people think that additives are not safe;
Only those who buy food only recognize "no XX additives", "0 add" and "no preservatives". I think such food is safer and healthy. Is this true?
In fact, as long as it is used reasonably, all food additives are safe, and there have been no cases of health damage caused by reasonable use of food additives to cause health damage.
Food additives are to improve food quality and color, aroma, taste, and adding artificial synthesis or natural substances in food for anti -corrosion, preservation and processing technology.
Its use has undergone very complicated and rigorous scientific assessment, and as long as it is used reasonably, it can ensure safety.
Taking preservatives as an example, all preservatives allowed by the national standard to be used by safety evaluations, standard use will not cause damage to consumers’ health.
The role of preservatives is to prevent food corruption from deteriorating, otherwise some foods will be broken before they leave the factory, and they may even produce toxins.
For example, the sausages we buy will use preservatives -nitrite. Its role is mainly to inhibit the growth and reproduction of Botox, and botox may produce a toxin toxin during the growth process -botulinum toxin, toxicity ratioThe frost is still strong.
Some foods that should be used reasonably and ensure safe food, but they do not use preservatives, creating "0 add" and "excluding preservatives", but they may bury food safety risks.
Those foods claiming to "do not contain XX additives", "0 add" and "no preservatives" will not be safer and healthier. Most of them are corporate marketing methods. Don’t be superstitious.
Author: Director of the Science and Technology Department of Ruan Guangfeng Food and Nutrition Information Exchange Center
Audit: Associate Researcher of the Institute of Nutrition and Health, Mastering China Disease Control and Control Center