many rumors say that blood donation is harmful to health. An article circulated on the Internet for a long time also enumerated several aspects, claiming that blood donation is harmful to the body. But are these statements reliable in the eyes of medical workers? Take a look at the criticism of these rumors by medical doctors and senior editors of health magazines.
rumor:
blood donation will weaken or even lose blood function. The reduction of red blood cells will make all parts of the body can not get enough oxygen, and the life functions of cells can not play normally. Dizziness after blood donation is because the brain does not get enough oxygen. Leucopenia will reduce the body’s ability to resist the virus and make it easy to get sick. The weakness after blood donation is this reason. The decline of immune ability makes the originally insignificant cold virus organic. The reduction of platelets will make the wound difficult to heal. The main cause of leukemia is thrombocytopenia. You may say that everyone says that the body will produce enough blood supplement after blood donation, but you know that all blood cells are differentiated from hematopoietic stem cells in the bone marrow. Hematopoietic stem cells have a long life. The book says that two weeks after blood donation, the blood volume will be replenished completely. But please note: what is added? Plasma, blood and plasma are two concepts. After blood donation, you will feel thirsty, that is, you need to supplement plasma. The blood station will provide sugar water or milk free of charge, which is why.
truth:
this rumor has many misunderstandings about the physiological process of body recovery after blood donation. We will explain the rumor one by one.
is the amount of blood donation a lot relative to the whole body blood?
usually donate 200ml of precious blood (such as type AB blood). Note: it is not necessarily Rh negative blood, because Rh negative blood is too rare. It often adopts the “alliance” method. As long as you join the “alliance”, when you need blood, other “allies” will donate blood to the blood station and assign it to the ally.) May require up to 400 ml. The interval between two acquisitions shall not be less than 6 (12 weeks in many other countries). 200ml is 0.2L, while the total amount of adult blood is about 4.2-4.8l. The amount of blood donation accounts for only about 5% of the whole body blood. It is not a large number for healthy people and will not cause any harm to the body. Women bleed 30 ~ 50 ml every month “those days”, and they bleed every month. Some large quantities can reach 80 ml; Six months add up to more than 200 ml. it’s not time to eat or travel. Some people still drink, exercise and have sex as usual. By comparison, it can be seen that the amount of blood donated is not much loss to the whole body.
why dizziness and nausea after blood donation?
some people who donate blood for the first time are prone to dizziness and nausea, which is usually due to changes in blood pressure and emotional pressure. Smoking and drinking can also aggravate dizziness. Blood pressure is the pressure of blood on blood vessels. Imagine you blow into a rubber pipe. The stronger you blow, the greater the pressure on the pipe wall. Blowing air from the mouth into the pipe is like the heart pumping blood into the blood vessels of the whole body. High blood pressure is often due to the poor elasticity of the blood vessel wall. Low blood pressure may be due to insufficient power of the heart to pump blood, slow heart rate and low blood volume (people who are injured and lose blood may be too low to measure blood pressure). But this blood pressure change will soon be adjusted by the body. If blood donation is always hypotension, patients with hypertension don’t have to take medicine. It’s better to bleed; There will be no “congestive heart failure” (peripheral blood pressure is too high and the heart pump doesn’t work). After blood donation, you often need to rest for a while, eat and drink. When you get up the next day, move gently and let your blood pressure adjust. Avoid fine labor when you feel uncomfortable. Don’t drink enough, especially if it’s not enough.
is it easy to get sick after blood donation?
leukocytes are indeed related to immunity, but they are not all factors that determine immunity. Just because you’ve been deducted 200 yuan this month doesn’t mean your family is poor. On the other hand, women will have a slight increase in leukocytes during menstruation, but there is no phenomenon that “women are less likely to get sick during menstruation”. On the contrary, some literatures also believe that older or postmenopausal blood donors can get rid of excess iron, which is related to heart attack – but the literature also notes that although this phenomenon has been observed, the correlation needs to be further confirmed.
blood donation leads to thrombocytopenia. Is it related to leukemia?
rumor:
“the main cause of leukemia is thrombocytopenia”. In fact, people collectively referred to as “leukemia” is a kind of blood disease in clinic. As long as the proportion of various components in the blood is unbalanced, it may cause the blood system to work abnormally, which is called “disease”. Their causes are not related, and even “leukocytosis” is not their only manifestation. Even when it comes to the narrow sense of “leukemia” mainly related to leukocytes, “thrombocytopenia” is only one of the manifestations, not its cause or inducement. And the recovery of platelets is not difficult. The textbook says that the life span of platelets is 7-10 days, and the aging platelets are cleared by the monocyte macrophage system. Unlike granulocytes, platelets have no reserve in bone marrow. If platelets are destroyed in large quantities, they recover slowly and can return to normal after at least 3-5 days, which is the time required for megakaryocytes to mature and produce platelets. In other words, you lost 5% of your platelets. Even if this is a “large amount”, it will recover in a few days. What about the other components in the blood? Water and inorganic salts will be replenished in 2 hours; Most other substances can be replenished in two days. The slowest recovery is the red blood cell, because its life span is 100-120 days. When it is obviously lost, the bone marrow will make blood at a rate of 6-8 times, and the recovery will not exceed 1 month. Therefore, the rumor that “the blood volume will be replenished 2 weeks after blood donation” does not describe the correct situation.
what kind of people can’t donate blood?
simply put, the situation of not allowing blood donation is that it is risky for blood donors or for blood users.
specifically includes: those who have recently donated blood (China stipulates 6 months); Underweight or overweight; Anemia; People with various infectious diseases or at risk of infectious diseases (for example, the UK stipulates that people who have had male sex within 12 months and tattoos within 4 months cannot donate blood; Singapore stipulates that people who have lived in Britain or France for a certain period of time will not donate blood – because of mad cow disease (CJD); People with malignant tumor or history; People with serious chronic diseases or autoimmune diseases… Etc. In addition, lactating mothers generally do not donate blood, especially within 6 months after delivery. Because this may reduce your body’s iron reserves, resulting in the risk of iron deficiency in infants.
how to supplement iron after blood donation?
food supplement. It should be noted that although many foods are rich in iron, iron in vegetables (including Popeye’s spinach), beans, Cereals, seaweed, eggs, cheese and shellfish are non hemoglobin iron that is not easy to absorb. Iron supplement still depends on animal liver, whole blood, fish and livestock and poultry meat.
how to rest after blood donation?
no heavy physical labor or intense exercise on that day. Drink more water than usual, 4 large cups, 250 ml each. Note that water, coffee or wine are not good. Do not stay in an overheated environment. What should be avoided: diet, less water, smoking, standing for a long time… These will affect your recovery.