Many people think that vitamin A is a nutrient element beneficial to the human body, so they want to supplement vitamin A in large quantities. In fact, this statement is wrong. Excessive consumption of vitamin A will also have side effects and harm to the body. The following details:
Excessive vitamin A intake is toxic. If infants take a large dose of vitamin A at one time, they will have acute vitamin A excess. The main poisoning symptoms were short-term hydrocephalus and vomiting.
In the past, it has also been reported that polar explorers suffered from acute vitamin A poisoning due to eating a large amount of polar bear liver rich in vitamin A. In adults with skin disease symptoms, taking vitamin A20 ~ 30 times the recommended supply (RDA), or taking a large amount of vitamin A for a long time without medical advice, resulting in chronic vitamin A excess.
The common symptoms of chronic vitamin A excess are fatigue, discomfort and drowsiness, sometimes accompanied by abdominal discomfort, bone or joint pain, severe pulsatile headache, even insomnia, irritability, night sweats, hair loss and brittle nails. Sometimes constipation, irregular menstruation and emotional instability occur.
Physical examination showed dry, rough and scaly skin, edema on the body surface and cracks on the corners of the mouth. Sometimes there are even exophthalmos. When making vitamin a tolerance curve, Chen rendun and others once took 10000 IU per kg body weight to the subjects. As a result, some users had symptoms such as headache, sleepiness and nausea, which were very similar to the symptoms described above.
The symptoms of excessive vitamin A in young children after taking large doses of vitamin A for a long time are mainly hepatosplenomegaly, reduction of red and white blood cells, excessive growth of bone marrow and brittle long bones, which are easy to fracture.
Side effects of taking too much vitamin A:
The side effect of vitamin A is that excessive intake of vitamin A can cause toxic reactions, which can be divided into acute, chronic and teratogenic reactions.
The symptoms of acute poisoning are nausea, vomiting, headache, dizziness and blurred vision. Infants can cause anterior chimney uplift.
Chronic poisoning is common. The symptoms include headache, bone and joint pain, fatigue, irritability, poor appetite, dry and itchy skin, cleft lip, hair loss and large liver. Excessive intake of vitamin A by pregnant women can affect the development of fetal bones, which will lead to fetal teratogenesis.