Selenium supplementation should not be excessive, and you can only drink 100 micrograms per day. Excessive intake of selenium can lead to poisoning, hair loss and nail loss. Clinical selenium poisoning caused by excessive selenium can be divided into acute, subacute and chronic. The main causes of poisoning are human body's direct or indirect intake and contact with a large amount of selenium, including occupational and geographical reasons, eating habits and drug abuse.
Clinical manifestations of selenium poisoning
Acute selenium poisoning: acute poisoning usually occurs after ingesting a large amount of selenium-enriched substances, and daily intake of selenium as high as 400 ~ 800 mg/kg body weight can lead to acute poisoning. The main manifestations are abnormal movements and postures, dyspnea, flatulence, high fever, rapid pulse, collapse and death due to respiratory failure.
Children with acute selenium poisoning generally have dizziness, headache, fatigue, lethargy, nausea, vomiting, diarrhea, garlic smell in breathing and sweat, and irritation symptoms in upper respiratory tract and conjunctiva. Severe cases include bronchitis, chills, high fever, sweating, finger tremor and hepatomegaly. Acute selenium poisoning is characterized by alopecia, nails, rash, peripheral neuropathy and mottled teeth color.
(2) Chronic selenium poisoning: Chronic selenium poisoning is often due to the intake of 2,400 ~ 3,000 micrograms of selenium from food every day, and symptoms only appear after several months. It is characterized by hair loss, nail loss, yellowing of skin, bad breath, fatigue, increased susceptibility to dental caries, depression and so on.
Chronic selenium poisoning generally includes dizziness, headache, fatigue, metallic taste in the mouth, nausea, vomiting, loss of appetite, diarrhea, garlic smell in breath and sweat, hepatomegaly, abnormal liver function, autonomic nerve dysfunction and increased urine selenium. Long-term high selenium makes children's body length and weight develop slowly, their hair is rough and fragile, and even nervous system symptoms and intellectual changes appear.
The main characteristics of chronic selenium poisoning are hair loss, nail morphological changes, deformity and cirrhosis, and some cases can also see skin lesions and nervous system abnormalities.
Extended data
The efficacy of selenium
1, selenium has anticancer effect. Selenium deficiency in human body is prone to liver cancer, lung cancer, gastric cancer, esophageal cancer, renal cancer, prostate cancer, bladder cancer, cervical cancer and leukemia. Selenium has antioxidant effect. Selenium is the best anti-aging substance. If the human body lacks selenium, it will "no longer be young" and lead to premature aging.
2. Selenium can enhance human immunity. Selenium deficiency reduces human immunity. Selenium can antagonize harmful heavy metals. Selenium deficiency can easily lead to poisoning symptoms of heavy metals such as lead, arsenic and cadmium.
3. Selenium can regulate the absorption and utilization of vitamin A, vitamin C, vitamin E and vitamin K. Selenium deficiency can cause myopia, cataract, retinopathy, fundus disease, age-related macular degeneration and other diseases. Selenium can regulate the synthesis of protein. Selenium deficiency can cause energy deficiency malnutrition and chromosome damage in protein.
4. Selenium can enhance reproductive function. Selenium deficiency can cause symptoms such as blocked ejaculation, low sperm motility, deformity, decreased pregnancy rate and increased incidence of metritis. Selenium is an essential component of peroxidase in seminal plasma. When the selenium content in semen decreases, the activity of this enzyme decreases, which can not inhibit the membrane peroxidation of sperm, resulting in sperm damage, increased dead sperm and decreased vitality.
5. Selenium is an important part of muscle function. Selenium deficiency can cause skeletal muscle atrophy and gray stripes, myocardial injury, myocardial cell density change, lipid increase and calcium deposition, leading to diseases. Therefore, men need to supplement selenium more, because most of the selenium supplied to the body is concentrated in the reproductive organs and can be excreted together with semen.
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