Hearing Xu Yi say this, Liu Liping remembered that the eldest sister in the dormitory took vitamin E capsules and wiped them on her face every day, and couldn't help asking: "You said that it is risky to supplement vitamin E like this, so wouldn't it be safer to directly wipe vitamin E capsules on your face?"

Xu Yi frowned and looked up at Liu Liping: "Smear?"

Liu Liping gestured with her hand and said, "Yes, it's like our bedroom boss just punctures the capsule with a needle, then squeezes the oil inside on his face, and then applies it evenly." ”

Xu Yi asked curiously, "What's the use of wiping this thing?"

Liu Liping said: "Whitening, isn't this vitamin E able to remove free radicals and prevent pigmentation?"

Xu Yi shook his head and said: "Isn't this nonsense, this thing is at best a free radical removal effect caused by ultraviolet rays, and there is no competitive inhibition or blocking the process of melanin synthesis with melanin synthesis, how can it have the effect of preventing pigmentation, do you think she has a little whiter than before she didn't use this thing?"

Liu Liping thought about it, it seemed that she had used it for two years, and if she thought about it, she really didn't see any changes, so she shook her head and said, "It seems that I can really see it." ”

Xu Yi nodded, "This human body only needs so much vitamin E a day, and these dozens or hundreds of milligrams of vitamin E are wiped on the face every day, which is absolutely excessive." I really don't know what the consequences will be in terms of the whole body, but one thing can be imagined. As he spoke, Xu Yi looked up at Liu Liping and asked her, "If I'm not mistaken, there is a chance that her skin will feel very dry now." ”

"Hey, you seem to have such a thing. She said that no matter what kind of makeup she used on her face, she felt dry, did that have any connection?"

Xu Yi said: "Of course there is a connection. In fact, this is already a very typical symptom of vitamin E poisoning. ”

Liu Liping's eyes widened and said, "Poisoning? Don't scare anyone. ”

"In fact, the reason is very simple, because vitamin E and vitamin A have a competitive inhibition relationship, too much vitamin E absorption, naturally inhibits the skin's ability to absorb vitamin A, and over time, it will naturally lead skin cells to absorb vitamin A. Skin vitamin A deficiency will lead to impaired glycoprotein synthesis, which leads to the accumulation of low molecular weight polysaccharides and lipids in cells, resulting in the proliferation and thickening of the basal layer of the epithelium, accelerated cell division, and increased tensile fibrillary synthesis. For a long time, wait until these cells divide out and move to the stratum corneum. Naturally, various symptoms appear. ”

"Theoretically, it is not excluded that it will lead to the immune protein synthesis disorder of the facial skin, so it is absolutely undesirable to apply vitamin E to the face, which is damaging the skin in disguise, and it takes a long time for the vitamin E that penetrates into the subcutaneous fat to be taken away by the blood or slowly penetrate into the cells of the basal layer, so the symptoms of skin drying out can only become normal after stopping the drug for a long time. ”

Hearing this, Liu Liping breathed a sigh of relief, fortunately she was relatively fair-skinned, otherwise she was afraid that she would have to use this again. Nodding his head, he said, "That's it, then I'll go back and quickly ask her to stop this, she wipes it every day, and she has to use up a bottle in about a month." But apparently she was also suspicious of the vitamin E in her body lotion. So I asked, "Then I also have vitamin E in my stuff, so it won't have any bad effects, right?"

Xu Yi shook his head and said, "I don't know the specific recipe for this thing. Presumably not too much, plus this weakly alkaline environment. I don't think there's anything left, so I shouldn't worry too much. ”

The fat man laughed: "That's it." This thing is not clearly marked to say how much of a certain ingredient in it, there is no fish in the fish balls, there is no kola nut in the cola, a bottle of vinegar with a drop of brewed vinegar dare to say that it is aged balsamic vinegar, you still need to worry about this cosmetics levy E exceeded, when the manufacturer really doesn't want to make money?"

Xu Yi said: "Vitamin E is a small molecule of fat-soluble substances, which is so difficult to absorb through the skin, not to mention fat-soluble substances that are larger than this large molecule, such as long-chain fats such as petroleum jelly in your thing, which can also not be absorbed by the skin, so the idea of rubbing something on the outside of the skin can provide nutrients to the skin, this idea is a little too simple." ”

"Basically, after the analysis of several types of substances, we know that at least as far as your body lotion is concerned, there is nothing that can have any nutritional effect on the skin, and you can imagine the role that other cosmetics can play - nothing more than covering the surface of the skin, making the skin look smoother, more natural in color, and you don't expect any skin care products to achieve nourishing the skin, or even the nutritional dermis, promoting collagen synthesis, they can't do anything. ”

"It can be said that preventing useless things from entering the body through the skin is also an important purpose of the skin defense skills, and the skin is kept moderately dry, which is also to better protect the stability of the internal environment. ”

"Don't believe the advertising or the feeling of someone's supervisor, as a medical worker who has been systematically studied, you can think about whether these cosmetics are reliable or not from the simplest clinical applications. ”

"Let's first talk about insulin-dependent diabetes requires insulin injections, you naturally know how this thing is used, right?"

After all, this is a professional thing, Liu Liping said without thinking: "I talked about it in this class, it should be injected into the subcutaneous tissue, and intravenous infusion will only be used when ketoacidosis and hyperglycemia are rescued." ”

"So why these two different ways?"

"The former requires the slow release of insulin to achieve the purpose of continuous blood sugar control and avoid the danger of rapid infusion of hypoglycemia, and the latter is to achieve the purpose of lowering blood sugar as much as possible. ”

"What are the most common side effects of insulin?"

"Allergies. ”

Xu Yi spread his hands with a smile and said: "Look, you know all this, it's just not combined with the actual results, if it's like you said, macromolecular proteins can be absorbed through the skin, then it's really good news for diabetics, so they don't have to inject insulin again, as long as it is directly applied to the skin like a ointment, it is more operable, but is it possible?"

Hearing Xu Yi say this, several people were thoughtful, and Liu Liping's face was even more red, and she smiled embarrassedly.

"For example, let's talk about colds, let's talk about the flu vaccine, this thing is a polysaccharide vaccine, and it also has to be injected under the skin, which is the same reason, doesn't it also prove that the skin has no absorption effect on these things. ”

"For example, if you really want to use collagen to fill wrinkles, either you choose surgery, or you can only rely on injections to work under the skin, but this is the same as insulin injections, and there is a risk of allergies. The same can be compared to those so-called topical drugs that can eliminate scars, you can imagine, these things can also not play any role, whether it is stretch marks or scars on the body surface, especially those with scar constitution, if you want to completely remove these scars, even surgery can not be completely done, at most just make these scars less conspicuous, those things can only reduce the pigmentation around the scars at most, but it is difficult to say whether it contains things that are harmful to the human body. ”

"After talking about these things that cannot be absorbed, let's talk about the things that can be absorbed, such as skin drugs containing steroid hormones, which are generally written on the instructions to prohibit large-scale or long-term use, which is naturally to prevent the skin from absorbing more hormones. ”

"And the skin will naturally be tighter under moderate dryness, which helps the human body to the influence of external adverse factors, from this point of view, the mask should not always be done, the stratum corneum after absorbing water can fight all kinds of damage will always be worse, so unless necessary, repeatedly apply cosmetics or so-called skin care products on the face, this behavior itself is the greatest harm to the skin. ”

"The aging of the dermis can be solved medically, such as injections and fillers, or the use of drugs to stimulate collagen secretion, etc., but these are undoubtedly risky, and there is no more meaning than beauty. The things that skin cells need cannot be improved by relying on one or two things given by cosmetics, and it can be said that at the cosmetics level, it is absolutely impossible to solve the fundamental problems of the skin by relying on skin care products. As for those advertisements, they often tell you some specious and very vague words. For example, vitamins are effective at scavenging free radicals, which is true, and then he says that his products contain a lot of superoxide dismutase. But what he won't tell you is that this superoxide dismutase is simply not possible to use on the surface of the skin to scavenge free radicals. ”

"As I said before, the meaning of the advertisement is that he gives you a hint: I have superoxide dismutase in it, and this thing is old, so my thing is high-end and high-grade!, but this does not mean that the superoxide dismutase in cosmetics can be absorbed by the skin and can play any role. ”

"People with dry skin, you have to consider whether the nutrition is not balanced, lack of necessary vitamin intake, or because of poor health or the secretion of the sebaceous glands is insufficient when you are older, so it is good to use some cream or something, if the sebaceous glands secrete too much, you need to use soap to remove some oil, but it is too much, if you wash too dry, you have to rub the moisturizer to replenish the oil!"

Liu Liping asked again: "Does that mean that it is useless to make a mask with egg white, milk or fruit?" (to be continued......)

PS: Well, that's it, I'm going to go out for a blood test in the afternoon, and I'll write tomorrow's update tomorrow.