Vitamin A

Vitamin A (vitaminA) (also called the retinol aldehyde derivative Rald) or antixerophthalmic factor, is an alicyclic unsaturated one yuan alcohol , including animal food sources of vitamin A1, A2 two, which is a kind of Retinol biological activity Material.
Vitamin A
Vitamin A1 found in Mammal and Saltwater fish In the liver, vitamin A2 often exist in freshwater fish liver. Because the activity of vitamin A2 is low, so usually say vitamin A is vitamin A1.
Vitamin A in the classification belongs to The fat soluble vitamins , belong to fat soluble vitamins and Vitamin D (also called ergocalciferol), Vitamin E (also known as tocopherol) and vitamin K (also known as coagulation; the other is vitamin) Water soluble vitamins Is the main. Vitamin B (including B1, B2, B3, B6, B12), Vitamin C (also called ascorbic acid ), Vitamin PP (also called Niacin ), Vitamin H (also called Biotin ) and Vitamin M (also called folic acid Etc.).
Plant sources Beta carotene And other Carotene In the human body can produce vitamin A, Beta carotene The highest conversion efficiency. In vivo, in beta carotene -15, 15 '- dioxygenase ( Dioxygenase ) under the catalysis of beta carotene can be converted to two molecules Rald (ratinal), retinol in retinal reduction enzyme Under the effect of reduction of retinol. but Beta Carotene can also be synthesized Astaxanthin (astaxanthin, strong antioxidant Agent), but only WuHan University School of pharmacy Bob Huang Professor Experiment Study on the operating room, to have the trial production stage in time.

Vitamin A Physicochemical properties

Vitamin A1
Molecular formula :
 C_%7B20%7DH_%7B30%7DO C_%7B20%7DH_%7B30%7DO
Chinese Name: vitamin A
Chinese alias: vitamin A; retinol
Referred to as: oral vitamin A
English Name: Vitamin A
CAS:68-26-8
EINECS:200-683-7
Molecular formula:
 C_%7B20%7DH_%7B30%7DO C_%7B20%7DH_%7B30%7DO
Molecular weight: 286.4516
InChI InChI=1/C20H30O/c1-16 (8-6-9-17 (2) 13-15-21) 11-12-19-18 (3) 10-7-14-20 (19,4) 5/h6,8-9,11-13,21H, 7,10,14-15H2,1-5H3/b9-6+, 12-11+, 16-8+, 17-13+
melting point : 62-64
boiling point : 137-138
Structure type:
Figure 1 Crocin 2. Annatto 3. Lycopene 4. Beta carotene 5. Xanthophyll 6. Zeaxanthin 7, canthaxanthin
Technical indicators
Project index
Requirements
Appearance
Pale yellow oily solution
smell
No rancid flavor, almost odorless or has a faint smell of fish
acid value
Less than 2.0mgKOH/g
lead
Less than 2.0ppm
arsenic
Less than 2.0ppm
Absorption coefficient ratio
More than 0.85

Project index
Requirements
Appearance
Pale yellow oily solution
smell
No rancid flavor, almost odorless or has a faint smell of fish
acid value
Less than 2.0mgKOH/g
lead
Less than 2.0ppm
arsenic
Less than 2.0ppm
Absorption coefficient ratio
More than 0.85

Vitamin A The production and Application

Vitamin A Production method

Natural vitamin A extracted by Cod Liver Oil. The marine fish liver extract is the retinol (vitamin A1), liver in freshwater fish extract is 3- dehydroretinol, vitamin A2.
The synthetic route of retinol and its derivatives have many, a common line of Isler, namely C13-C14-C20.
The beta ionone condensation with ethyl chloroacetate, by hydrolysis and decarboxylation Gheed fourteen carbon aldehyde; the other by Sodium acetylide and Methyl vinyl ketone The condensation material obtained with ethyl magnesium bromide reaction double magnesia-based bromide. The double bromine magnesium compound with fourteen carbon aldehyde condensation, hydrolysis, catalytic hydrogenation of hydroxy vitamin A and acetyl chloride effect hydroxy vitamin acetate, then bromination debromination vitamin acetate.

Vitamin A The application of traditional Chinese Medicine

As early as 1000 years ago, The Tang Dynasty Sun Simiao in " Prescriptions "Recorded in the treatment of animal liver Night blindness . " In the "Cloud:" black eyed pupil in the Yin, the blood vessels on the conjunctiva in Yang, yin and yang to clear." This weak and not with Yang, complex and long make gasification adverse, loss of kidney essence binocular hepatic blood filling raise blindness. The method of quasi tonifying the liver and kidney, essence and blood, ventilation mainly accompanied by Qinggan eyesight Yanggan products, and Yu more haggard, it should be supplemented with Shuganjieyu medicine: Rehmannia 20, Chinese yam 20, jujube 18, Dan 15, Ze Xi 15, Poria 15, cinnamon 20, 20 medlar, chrysanthemum 15 Sha Wan, 15, Tusizi 15, full jade son Qin to 15, 15, 30 and 15 Alpinia oxyphylla, Radix Paeoniae Alba, Ukraine 18 taiwan. Fang corrigent cinnamon set fire to the source, with Ze xi, Poria cocos Yang, dampness, with intelligence, Taiwan Ukraine, reduction of urine to cure urination and astringent to the tears.
So much from Chinese herbal medicine in ancient Monarch The compatibility of the law, make vitamin A infiltration from the treatment of eye diseases. (including diabetic ophthalmopathy)

Vitamin A Effect

Vitamin A is a fat soluble alcohols, with various molecular forms. The VA1 mainly in animal liver, blood and retina, called retinol, the melting point of 64 DEG C, molecular formula C20H30O, VA2 mainly exists in the freshwater fish, with a melting point of 17 to 19 DEG C, molecular formula C20H28O.
Vitamin A is composed of rhodopsin feel weak light of the composition of visual cells in rhodopsin from opsin and 11 - cis - retinal composition, with the dark vision.
The excessive intake of vitamin A will appear dry skin, scaling and Alopecia Other symptoms.

Vitamin A physiological function

1, maintain the normal visual function
The eye is the photoreceptor retina The rods and cones. These two kinds of cells are Photosensitive pigment That is, the sense of weak light rhodopsin and iodopsin light. Rhodopsin and iodopsin are made with opsin retinaldehyde formed. Rhodopsin by light irradiation, 11- CIS retinaldehyde heterogeneous trans retinal and opsin separation and pale, this process is called "bleaching". If entering the dark, due to weak light sensitive rhodopsin disappeared, so can't see things.
After the separation of retinyl aldehyde was reduced to all trans retinaldehyde, further into trans retinyl esters (or heterogeneous CIS) and stored in the pigment epithelium. The retina yellow retinyl ester hydrolase, will be transformed into trans retinol, through oxidation and isomerization, the formation of 11- CIS retinaldehyde. With the re combination of protein rhodopsin, restore sensitivity to weak light and dark to see things in a certain illumination, this process called dark (DarkAdaptation). Retinol and retinol binding protein released by the liver (RBP) combination in plasma combined with albumin, delivered to the retina, the photochemical reaction in the retina, if plenty of vitamin A, then the regeneration of rhodopsin quickly and completely, so the dark adaptation time is short; if a lack of vitamin A, then rhodopsin regeneration of slow and incomplete, so the dark adaptation time prolonged, serious when can produce night blindness (NightBlindness).
2, the maintenance of epithelial cells and promote the health of immunoglobulin synthesis
The synthesis of vitamin A may be involved in glycoprotein, the epithelium of the normal formation, development and maintenance is very important. When vitamin A deficiency, can cause abnormal intermediates of glycoprotein synthesis, low molecular weight polysaccharide and lipid accumulation caused by thickening of the basal epithelium, accelerate cell division, Zhang Liyuan synthetic fiber increased, surface layer cells became flat, irregular, drying and other changes. The nose, pharynx and throat and other respiratory, gastrointestinal and urogenital endometrial keratinization, weaken the natural barrier to prevent bacterial invasion (structure), and prone to infection. In children, easily associated with respiratory tract infection and diarrhea. Some kidney stones and urinary tract related keratinize. Excessive intake of vitamin A on epithelial infection resistance is not increased with the dose.
Immunoglobulin is a glycoprotein So, vitamin A can promote the synthesis of the protein, the immune function has an important influence, the lack of time, cell immunity decreased.
3, maintain normal skeletal growth and development
Vitamin A promotes differentiation of the biosynthesis of protein and bone cell. When it is lacking, osteoblasts and osteoclasts balance is destroyed, or due to enhanced osteogenic activity and bone hyperplasia, or make the formation of bone without absorption. If pregnant women lack of vitamin A will directly affect fetal development, even stillbirth.
4, promote the growth and reproduction.
Vitamin A contributes to cell proliferation and growth. Animal lack of vitamin A, apparent growth arrest, and loss of appetite and animal protein utilization rate decreased. Vitamin A deficiency, effects of male animal epithelial spermatic producespermatocytes, female vaginal epithelial cycle changes, also affect the placental epithelium, the embryo formation is blocked. Vitamin A deficiency also decreased as catalytic precursors for the formation of progesterone enzyme activity, the adrenal gland and gonad steroid and placenta reduced, may affect the reproductive function.
5, inhibition of tumor growth
Clinical trials showed that vitamin A acid (retinoic acid) compounds with delay or prevent precancerous lesions, prevent chemical carcinogens, especially for epithelial tumor, clinically used as adjuvant therapy agent has achieved good effect. Beta carotene Has antioxidant properties, near a large number of reports, the body is an effective antioxidant for the capture of active oxygen, prevent lipid peroxidation, prevention of cardiovascular disease, cancer, and delayed senescence has important significance.
6, nutritional supplements
As a nutritional additive in cosmetics, can prevent rough skin, promote the normal growth and development, can be used in cream emulsion.
Although there are a few more vitamin A and more beneficial to the human body function, but with other nutrients, however, excessive intake can cause headache, nausea, diarrhea, hepatosplenomegaly, should be consumed in moderation.

Vitamin A function

1 with the regulation of epidermis and cuticle The new supersedes the old. effect, can resist Be senile To wrinkles.
2 can reduce seborrhea and make the skin elastic, fade spots, soft skin.
3 help to protect the skin, mucosa from germs, healthy skin, prevent skin cancer.
4 prevent night blindness, visual impairment, the treatment of various diseases of the eye, the eyes of good ignorant woman.
5 help to promote bone growth, tooth growth, regeneration.
6 effective in preventing obesity, women keep slim.
7 can contribute to the prevention and treatment of hair loss.
utility
1 prevent Night blindness And vision loss, helpful to the treatment of various diseases of the eye (vitamin A can promote the formation of ocular photopigment);
2 have the effect of anti infection of respiratory system;
3 helps the immune system function;
4 ill a speedy recovery;
5 to maintain the health of tissue or organ surface;
6 helps get rid of senile plaques;
7 promote the development, strong bones, skin, hair, teeth, maintain healthy gums;
8 external help to acne, pustule, boils, treatment of skin ulcer;
9 help to emphysema , Thyroid Treatment of hyperthyroidism.
10 contribute to the treatment of hair loss.

Vitamin A Pharmacological response

This product can be easily absorbed after oral administration, the main storage in the liver. Almost all of the in vivo metabolism of beta carotene is the precursor of Vit A, in the animal intestinal mucosa can be transformed into activated Vit A. Mainly through the urine and feces, and only a small amount of breast milk excretion.
Beta carotene is fat soluble antioxidants. Facklman (1990) study shows that beta carotene can prevent obstructive atherosclerosis, coronary heart disease and stroke and other diseases in the elderly, they think that beta carotene can prevent the oxidation of LDL formation of oxidized LDL, and oxidized LDL toxicity can lead to vascular epithelial cell injury, thus accelerating lipid deposition in the the injury and plaque formation, and vascular obstruction, cause obstructive diseases such as atherosclerosis.
Vitamin A treatment of dry eye, keratomalacia, dry skin and night blindness etc.. In addition, it has good curative effect on scald, frostbite and ulcer.
Vitamin A can increase the number of spleen PFC sheep red blood cells or protein immunized mice, enhanced T cell dependent antigen to antibody production. It can also enhance the human peripheral blood lymphocytes in response to PHA and NK cell activity, improve the activity of macrophage, stimulate T cell proliferation and IL 2.

Vitamin A Absorption and metabolism

Vitamin A in the digestive tract, the stomach almost not absorbed in the small intestine and bile acid fat decomposition product is emulsified together, absorbed by the intestinal mucosa. Vitamin A body storage capacity is increasing with age, to old age was significantly lower than that of young people of different gender, different amount of storage. Vitamin A in the body of the average half period of 128~154 days, in the absence of vitamin A intake, daily loss of liver (catabolism) rate is about 0.5%.
Suitable for long time, the fat malabsorption of vegetarian, long-term wear contact lenses and long time staring at the computer screen; poor body resistance, high cholesterol levels, should be appropriate to add beta carotene; often supplement vitamin C, E, and beta carotene can be synergistic.
From food classification into three categories of food sources, usually can be divided into animal food, such as: Cod-liver oil , Egg Etc.; plant foods, are mainly dark green or red and yellow vegetables, fruits, such as Carrot Sweet potato, red, Mango , Pepper and Persimmon ; there is a medicinal and edible food, such as psyllium, windproof, perilla, Patchouli , Fruit of Chinese wolfberry Etc..
 Mango is rich in vitamin A Mango is rich in vitamin A
From the perspective of vitamin A structure, there are two main sources: one is the source of vitamin A, also refers to the beta carotene and other carotenoids. Many found in plant foods, such as green leafy vegetables, vegetables and yellow
 Fruits Fruits
Fruit, rich content of spinach, alfalfa, pea sprouts, red sweet potatoes, carrots, green peppers, pumpkins, etc.. The other is to vitamin A (retinol), mainly in animal foods, can be directly absorbed and utilized by the body, mainly in animal liver, milk and dairy products (milk and eggs).
According to the analysis of food table shows, average every (100 grams) contains vitamin A is most abundant (about 12000 units) is the green leafy vegetables, such as kale, chard, spinach and other green vegetables. Even a beans, broccoli, carrots, pumpkin, sweet potato, yellow apricot or yam can also provide 5000 units of vitamin A, which is the day the amount required for adults. A content of tomatoes, celery, lettuce, peas and asparagus in the average amount of nearly 2000 units. In addition to apricot yellow fruit, most of the contents of vitamin A in A are less than 400 units. Has lost the original color or never become lack of this vitamin green vegetables.
See from the food analysis table, animal liver contain extremely rich in vitamin A, and contains animal kidney and offal in quantity is also very high. Vitamin A cannot be stored in the muscle, barbecue, fried meat and meat in the lack of this vitamin. Egg and milk contains vitamin A, which depends on the number of animal food intake. The content of vitamin A per liter of whole milk in 500 ~ 7000 units, but the average is 2000 units. The milk was homogenized most of the vitamin A will be destroyed by oxygen, but so far, mankind has yet to find a way to solve this problem. The cow milk production in fed hay for the winter after the butter, each containing 450 grams of butter in the winter of vitamin A may be only 2000 units, and each of the 450 Yorkshire average is 12000 units of butter. Every 450 grams of butter instead of the addition of vitamin A in usually 12000 units.
Cod Liver Oil is commercially the most abundant source of vitamin A . Contained in animal liver vitamin A depends on the move
 Vegetables Vegetables
Food and animal feeding by age. In addition to the polar bear liver, has confirmed the most abundant vitamin A is the London Zoo a 100 year old Python liver oil, vitamin A content in Cod Liver Oil halibut is more abundant than cod in Cod Liver Oil, this is because the halibut listed for sale than cod are old, sold on the market cod generally are quite small, halibut and therefore have more years of feeding the sea green algae. The same reason, including adult cow and sheep liver vitamin A than Dallas and lamb livers contained more vitamin A.
1 of the recommended daily intake of vitamin A , general adult males, 1000RE (or 5000IU) can prevent the lack of.
2.10 ~ 15 years old girl recommended daily intake of 4600 international units.
Women over the age of 3.16 recommended daily intake of 4200 international units.
4 adults daily eat about 0.85 lemons can meet the needs of adults to eat only 1/2 daily; carrot; adult
 Balanced nutrition Balanced nutrition
One day only eat 1 pieces of mango can satisfy the needs of adults; daily to eat only 1 asparagus can satisfy the needs.
5 pregnant women need to pay special attention to the safe use, in order to avoid malformation. During pregnancy, the initial intake is not recommended to increase.
6 lactating women, an increase of 2500 units in the first 6 months; 6 months after the additional 2000 international units.
The content of the food table
 The food of vitamin A and retinol content The food of vitamin A and retinol content

Vitamin A influence factor

Promote and affect the absorption factor
1, in the small intestine bile is required for vitamin A emulsion.
2 dietary fat, enough fat can promote the absorption of vitamin A.
3 antioxidants, such as vitamin E and lecithin, is conducive to the absorption.
4 use of mineral oil and intestinal parasites is not conducive to the absorption of vitamin A.
5 vitamin C has a destructive effect on vitamin A. Especially after large doses of vitamin C, can promote the excretion of vitamin A in the body, so, in large doses of vitamin C at the same time, we must pay attention to intake of vitamin A should be sufficient. Vitamin A can prevent vitamin C by oxidation.
6 and carotene together into the body of polyunsaturated fatty acids (polyurisatu-rated fatty acids), if there is no antioxidant substances exist, would interfere with the action of vitamin A.
7 were taking oral contraceptives, must reduce the amount of vitamin A.
8 with the use of vitamin A and vitamin B, D, E, calcium, phosphorus and zinc, can give full play to its function (must have zinc can release stored in the liver of vitamin A).
No special instructions 9 veterinary, not to take vitamin A in dogs and cats.
10 taking cholesterol lowering drugs, such as cholestyramine (Questran, Cholesty, ramine) on the absorption of vitamin A will reduce, then taking supplements.

Vitamin A Excessive performance

Vitamin A Common symptoms

Vitamin A is fat soluble vitamins and fat soluble vitamins like water soluble vitamins like that, even if the use of excessive not prone to poisoning phenomenon, fat soluble vitamin overdose can often occur poisoning performance, what are the symptoms of vitamin A overdose? Here we have to introduce the signs and symptoms of excessive vitamin A.
The symptoms of excessive vitamin a performance can be roughly divided into two types, one is a one-time intake of vitamin A can cause acute hypervitaminosis A, another is chronic cumulative poisoning. If the adult intake dose of vitamin A reached or exceeded 90-300mg (30-100 000 IU), children if the one-time intake of more than 90mg (300 thousand IU) is likely to occur in acute vitamin a poisoning. Children often because of excessive food intake caused by Cod Liver Oil used to Cod Liver Oil, because the prevention of rickets in children, Cod Liver Oil in rich in vitamin D, but also contains a lot of vitamin A. The symptoms of adult vitamin A excess usually occur in a large number of intake of vitamin A after 6-8 hours, may appear to be over excited, others as lethargy, may have a headache, vomiting and other symptoms of increased intracranial pressure, 12-20 hours after the skin will appear red and thick, what happened in the soles of the feet, peeling. The palm skin thickest was the most obvious, require several weeks to recover gradually. While infants mainly for increased intracranial pressure, in addition to lethargy or vomiting, will appear anterior fullness, fundus edema and other symptoms, serum vitamin a content increased significantly, up to 500 g/L above the normal adult should be 100 ~ 300 g/L. Second kinds of symptoms of vitamin A excess is the performance of chronic poisoning, mostly because of chronic accumulation. If the adult daily intake of vitamin a content in 24 ~ 30mg (8 ~ 100 thousand IU), if you do not pay attention to it for half a year, or every 9 ~ 12mg (3 ~ 40 thousand IU), more than 8 years can cause chronic poisoning. The infant daily intake of 15 ~ 30mg (50 thousand ~ 100 thousand IU), more than 6 months can cause chronic poisoning, there are also reports every day only 7.5mg (25 thousand IU), a month that the symptom of poisoning, so vitamin A poisoning in children than in adults, not easily tolerated.
The symptoms of adult vitamin A excess performance change is relatively slow and persistent, early there will be loss of appetite, weight loss, then slowly dry skin, peeling, chapped, hair loss, joint swelling and possible bone pain, hepatosplenomegaly, cortical bone hyperplasia, some people will have increased calcium, calcium and high urine, even there will be liver cirrhosis.
The symptoms of infantile vitamin A overdose can be from the following points: to fully explain the general symptoms of infantile vitamin A overdose showed restlessness and anorexia. One is the change in the skin and mucous membrane, these changes showed a more performance for the rough skin dry, have seborrhea like rash or scattered in the body maculopapule. Some patients showed a thin skin and shiny, with flake peeling or crumbs, hair scarce and dry hair. The baby is not closed because the anterior fontanelle showed full bregma, even those with sutures left, children often because of headache and crying. Increased intracranial pressure may be due to excessive secretion of cerebrospinal fluid or because it is related to the absorption barrier, and after discontinuation of intracranial pressure recovery slower.
The symptoms of infantile vitamin A excess performance of the two is the change of the skeletal system, metastatic bone pain occurred more frequently in the forearm and lower leg and limbs, can affect the ulna, radius and tibia. Pressure pain, visible local soft tissue swelling, bone pain may occur in different parts may also occur repeatedly in the same position.
The symptoms of third infants with vitamin A excess performance is by involving the liver, excessive vitamin A, can damage the liver, can appear aminotransferase increased, the person will be even liver cirrhosis, ascites, stop after two months between applications often need.
Infant vitamin A overdose can affect children's growth and development, the mother during pregnancy can lead to excessive intake of vitamin A, monstrum occur, mostly in craniofacial, urinary or cardiovascular malformation.
The symptoms of excessive vitamin A showed increased urinary calcium in kidney, and hyperuricemia, manifested in the blood system have hypoplastic anemia, white blood cells decreased, prothrombin is low, and there may be epistaxis and gingival bleeding
In short, the symptoms of excessive vitamin a performance is complicated, and the symptoms are not typical, often early is not easy to be found, if the doctor can not be well aware of the existence of an overdose of interrogation history of vitamin A, often leads to misdiagnosis and delaying the disease, so as tending infant parents must pay attention to, when the children use the Cod Liver Oil must strictly control the amount of, can not think that it is not controlled and nutritional supplements.
Vitamin A is composed of rhodopsin feel weak light of the composition of the visual cells in the human body lacks vitamin A, affect the dark adaptation capabilities, such as children dysplasia, dry eye, night blindness, etc.. The human body excessive intake of vitamin A will appear symptoms of dry skin, desquamation and alopecia.

Vitamin A Type of poisoning

Excessive intake of the human body Vitamin A can cause poisoning The syndrome, called Vitamin A poisoning (Vitamin A toxicity). The post thousand in 1590s, occurrence of Arctic explorer polar bear liver hours after eating headache Vomiting, lethargy, disease, human and animal body vitamin A90 ~ 95% is stored in the liver. Due to the domestic abuse of vitamin A concentrate, poisoning Symptom Who continues to increase, mainly because the parents lack of reasonable application of vitamin A that the amount of knowledge, the more the better, the medical staff is also a lack of vigilance, worthy of attention.
Vitamin A poisoning can be divided into the following two types:
1 acute type due to the sensitivity of vitamin A in children with individual differences, and liver vitamin A storage capacity of different toxic doses can have great difference. General vitamin A injection of 300000IU, in a few days have symptoms of poisoning. Show Appetite Loss, irritability or lethargy, vomiting, anterior fontanelle bulge, increased head circumference, cranial suspected dehiscence, papilla edema Etc.. Intracranial hypertension is common in acute type, due to increased absorption or cerebrospinal fluid like disorder caused by. If there is no sign for children with nervous system infection, sudden symptoms of increased intracranial pressure, combined with the intake of vitamin A and vitamin A after discontinuation of medical history, symptoms quickly disappeared, the diagnosis can be established.
2 chronic vitamin A daily amounts to tens of thousands of units, such as infant daily intake of vitamin A per kilogram of body weight of 1500IU, but in a few days after the poisoning symptoms. Early irritability, anorexia, fever, sweating, Alopecia And after the typical symptom of pain, a metastatic pain may be associated with soft tissue swelling, tenderness and no signs of red, hot, long bone and bone to see more, because of long bone involvement of epiphyseal embedding, can lead to short stature. In some cases, temporal occipital pain, may be misdiagnosed as bone sclerosis. Increased intracranial pressure symptoms such as headache, vomiting, anterior wide uplift, cranial suture separation, eyes esotropia, Nystagmus Another feature, such as diplopia of the disease, but a rare type of acute. In addition, there are itching, desquamation, rash, chapped lips, dry hair, liver Splenomegaly , abdominal pain , myalgia, hemorrhage, renal lesions, and hypoplastic anemia companion white blood cell Reduce etc.. Serum alkaline phosphatase is increased. Abroad have reported long-term hepatosplenomegaly can cause liver cirrhosis, portal pressure increased, and even death.

Vitamin A Recommended intake

China residents recommended vitamin A intake (RNI)
Age / age
RNI (gRE*)
Age / age
RNI (gRE*)
0~
Four hundred
14~
800 male and 700 female
0.5~
Four hundred
18~
800700
1~
Five hundred
Pregnant woman:
initial stage
Eight hundred
4~
Six hundred
 
Metaphase
Nine hundred
7~
Seven hundred
 
Later stage
Nine hundred
11~
Seven hundred
Wet nurse
One thousand and two hundred

China residents recommended vitamin A intake (RNI)
Age / age
RNI (gRE*)
Age / age
RNI (gRE*)
0~
Four hundred
14~
800 male and 700 female
0.5~
Four hundred
18~
800700
1~
Five hundred
Pregnant woman:
initial stage
Eight hundred
4~
Six hundred
Metaphase
Nine hundred
7~
Seven hundred
Later stage
Nine hundred
11~
Seven hundred
Wet nurse
One thousand and two hundred
Note *:RE retinol equivalent

Vitamin A Toxic substances

Toxicity test data reported in the literature,
number
Toxic type
test method
Test object
Dose
One
acute toxicity
Oral
Adult female
91000 iu/kg/26W-I
Two
acute toxicity
Oral
children
5475 ku/kg/1Y-I
Three
acute toxicity
Oral
Adult male
1217 ku/kg/1Y-I
Four
acute toxicity
Oral
children
912 ku/kg/2Y-I
Five
acute toxicity
Oral
baby
442 ku/kg/11D-I
Six
acute toxicity
Oral
Rat
2 mg/kg
Seven
acute toxicity
Oral
mice
1510 mg/kg
Eight
acute toxicity
intraperitoneal injection
mice
1510 mg/kg
Nine
Chronic toxicity
Oral
Rat
73 mL/kg/16D-I
Ten
Chronic toxicity
intraperitoneal injection
Rat
73 mL/kg/16D-I
Eleven
Mutation toxicity
 
Human lymphocyte
17 umol/L
Twelve
Mutation toxicity
 
Human lymphocyte
4 mg/L
Thirteen
Mutation toxicity
 
Human lymphocyte
8 mg/L
Fourteen
Mutation toxicity
 
Human lymphocyte
4 mg/L
Fifteen
Mutation toxicity
Parenteral
Rat
20700 mg/kg/69W (discontinuous)
Sixteen
Mutation toxicity
 
Rat breast
3 umol/L
Seventeen
Mutation toxicity
 
Lymphocytes of mice
100 umol/L
Eighteen
Mutation toxicity
Parenteral
mice
15600 mg/kg/1Y (discontinuous)
Nineteen
Mutation toxicity
 
Lymphocytes of mice
10 umol/L
Twenty
Mutation toxicity
 
Hamster cells
8 mg/L
Twenty-one
Mutation toxicity
 
Hamster cells
24 mg/L
Twenty-two
Reproductive toxicity
Oral
Adult female
68 mg/kg, 1-39 weeks pregnant female
Twenty-three
Reproductive toxicity
Oral
Adult female
200 mg/kg, 8 weeks pregnant female
Twenty-four
Reproductive toxicity
Oral
Rat
76560 days after ug/kg, 8-10
Twenty-five
Reproductive toxicity
Oral
Rat
113 mg/kg, 10 days later
Twenty-six
Reproductive toxicity
Oral
Rat
150 days after mg/kg, 7-10
Twenty-seven
Reproductive toxicity
Oral
Rat
683 days after mg/kg, 4-16
Twenty-eight
Reproductive toxicity
Oral
Rat
22 days after mg/kg, 1-22
Twenty-nine
Reproductive toxicity
Oral
Rat
240 mg/kg, 9 days later
Thirty
Reproductive toxicity
Oral
Rat
1200 days after ku/kg, 6-17
Thirty-one
Reproductive toxicity
intraperitoneal injection
Rat
60060 ug/kg, 10 days later
Thirty-two
Reproductive toxicity
intraperitoneal injection
Rat
60 mg/kg, 10 days later
Thirty-three
Reproductive toxicity
intraperitoneal injection
Rat
60 mg/kg, 10 days later
Thirty-four
Reproductive toxicity
intraperitoneal injection
Rat
30 mg/kg, 11 days later
Thirty-five
Reproductive toxicity
Parenteral
Rat
150 mg/kg, 10 days later
Thirty-six
Reproductive toxicity
No report
Rat
72 days after mg/kg, 11-13
Thirty-seven
Reproductive toxicity
No report
Rat
150 mg/kg, 9 days later
Thirty-eight
Reproductive toxicity
Oral
mice
30 mg/kg, 3 days later
Thirty-nine
Reproductive toxicity
Oral
mice
120 mg/kg, 12 days later
Forty
Reproductive toxicity
Oral
mice
9610 days after mg/kg, 8-12
Forty-one
Reproductive toxicity
Oral
mice
30 mg/kg, 1 days
Forty-two
Reproductive toxicity
Oral
mice
375 mg/kg, pregnant female 7-11 days
Forty-three
Reproductive toxicity
intraperitoneal injection
mice
45045 ug/kg pregnant female 8 days
Forty-four
Reproductive toxicity
intraperitoneal injection
mice
145 mg/kg pregnant female 8 days
Forty-five
Reproductive toxicity
intraperitoneal injection
mice
145 mg/kg pregnant female 9 days
Forty-six
Reproductive toxicity
intraperitoneal injection
mice
145 mg/kg pregnant female 10 days
Forty-seven
Reproductive toxicity
intraperitoneal injection
mice
180 mg/kg pregnant female 10 days
Forty-eight
Reproductive toxicity
subcutaneous injection
mice
96 mg/kg, pregnant female 11-14 days
Forty-nine
Reproductive toxicity
subcutaneous injection
mice
480 mg/kg, pregnant female 11-14 days
Fifty
Reproductive toxicity
intraperitoneal injection
mice
20 mg/kg pregnant female 8 days
Fifty-one
Reproductive toxicity
intravenous injection
mice
12 mg/kg pregnant female 8 days
Fifty-two
Reproductive toxicity
intramuscular injection
mice
480 mg/kg, pregnant female 10-13 days
Fifty-three
Reproductive toxicity
intramuscular injection
mice
120 mg/kg pregnant female 8 days
Fifty-four
Reproductive toxicity
intramuscular injection
mice
240 mg/kg, pregnant female 14-17 days
Fifty-five
Reproductive toxicity
Oral
Rabbit
45 mg/kg pregnant female 12 days
Fifty-six
Reproductive toxicity
Oral
Mammal
77 mg/kg, pregnant female 8-18 days
Fifty-seven
Reproductive toxicity
intraperitoneal injection
Mammal
52550 days after ug/kg, 9-15

number
Toxic type
test method
Test object
Dose
One
acute toxicity
Oral
Adult female
91000 iu/kg/26W-I
Two
acute toxicity
Oral
children
5475 ku/kg/1Y-I
Three
acute toxicity
Oral
Adult male
1217 ku/kg/1Y-I
Four
acute toxicity
Oral
children
912 ku/kg/2Y-I
Five
acute toxicity
Oral
baby
442 ku/kg/11D-I
Six
acute toxicity
Oral
Rat
2 mg/kg
Seven
acute toxicity
Oral
mice
1510 mg/kg
Eight
acute toxicity
intraperitoneal injection
mice
1510 mg/kg
Nine
Chronic toxicity
Oral
Rat
73 mL/kg/16D-I
Ten
Chronic toxicity
intraperitoneal injection
Rat
73 mL/kg/16D-I
Eleven
Mutation toxicity
Human lymphocyte
17 umol/L
Twelve
Mutation toxicity
Human lymphocyte
4 mg/L
Thirteen
Mutation toxicity
Human lymphocyte
8 mg/L
Fourteen
Mutation toxicity
Human lymphocyte
4 mg/L
Fifteen
Mutation toxicity
Parenteral
Rat
20700 mg/kg/69W (discontinuous)
Sixteen
Mutation toxicity
Rat breast
3 umol/L
Seventeen
Mutation toxicity
Lymphocytes of mice
100 umol/L
Eighteen
Mutation toxicity
Parenteral
mice
15600 mg/kg/1Y (discontinuous)
Nineteen
Mutation toxicity
Lymphocytes of mice
10 umol/L
Twenty
Mutation toxicity
Hamster cells
8 mg/L
Twenty-one
Mutation toxicity
Hamster cells
24 mg/L
Twenty-two
Reproductive toxicity
Oral
Adult female
68 mg/kg, 1-39 weeks pregnant female
Twenty-three
Reproductive toxicity
Oral
Adult female
200 mg/kg, 8 weeks pregnant female
Twenty-four
Reproductive toxicity
Oral
Rat
76560 days after ug/kg, 8-10
Twenty-five
Reproductive toxicity
Oral
Rat
113 mg/kg, 10 days later
Twenty-six
Reproductive toxicity
Oral
Rat
150 days after mg/kg, 7-10
Twenty-seven
Reproductive toxicity
Oral
Rat
683 days after mg/kg, 4-16
Twenty-eight
Reproductive toxicity
Oral
Rat
22 days after mg/kg, 1-22
Twenty-nine
Reproductive toxicity
Oral
Rat
240 mg/kg, 9 days later
Thirty
Reproductive toxicity
Oral
Rat
1200 days after ku/kg, 6-17
Thirty-one
Reproductive toxicity
intraperitoneal injection
Rat
60060 ug/kg, 10 days later
Thirty-two
Reproductive toxicity
intraperitoneal injection
Rat
60 mg/kg, 10 days later
Thirty-three
Reproductive toxicity
intraperitoneal injection
Rat
60 mg/kg, 10 days later
Thirty-four
Reproductive toxicity
intraperitoneal injection
Rat
30 mg/kg, 11 days later
Thirty-five
Reproductive toxicity
Parenteral
Rat
150 mg/kg, 10 days later
Thirty-six
Reproductive toxicity
No report
Rat
72 days after mg/kg, 11-13
Thirty-seven
Reproductive toxicity
No report
Rat
150 mg/kg, 9 days later
Thirty-eight
Reproductive toxicity
Oral
mice
30 mg/kg, 3 days later
Thirty-nine
Reproductive toxicity
Oral
mice
120 mg/kg, 12 days later
Forty
Reproductive toxicity
Oral
mice
9610 days after mg/kg, 8-12
Forty-one
Reproductive toxicity
Oral
mice
30 mg/kg, 1 days
Forty-two
Reproductive toxicity
Oral
mice
375 mg/kg, pregnant female 7-11 days
Forty-three
Reproductive toxicity
intraperitoneal injection
mice
45045 ug/kg pregnant female 8 days
Forty-four
Reproductive toxicity
intraperitoneal injection
mice
145 mg/kg pregnant female 8 days
Forty-five
Reproductive toxicity
intraperitoneal injection
mice
145 mg/kg pregnant female 9 days
Forty-six
Reproductive toxicity
intraperitoneal injection
mice
145 mg/kg pregnant female 10 days
Forty-seven
Reproductive toxicity
intraperitoneal injection
mice
180 mg/kg pregnant female 10 days
Forty-eight
Reproductive toxicity
subcutaneous injection
mice
96 mg/kg, pregnant female 11-14 days
Forty-nine
Reproductive toxicity
subcutaneous injection
mice
480 mg/kg, pregnant female 11-14 days
Fifty
Reproductive toxicity
intraperitoneal injection
mice
20 mg/kg pregnant female 8 days
Fifty-one
Reproductive toxicity
intravenous injection
mice
12 mg/kg pregnant female 8 days
Fifty-two
Reproductive toxicity
intramuscular injection
mice
480 mg/kg, pregnant female 10-13 days
Fifty-three
Reproductive toxicity
intramuscular injection
mice
120 mg/kg pregnant female 8 days
Fifty-four
Reproductive toxicity
intramuscular injection
mice
240 mg/kg, pregnant female 14-17 days
Fifty-five
Reproductive toxicity
Oral
Rabbit
45 mg/kg pregnant female 12 days
Fifty-six
Reproductive toxicity
Oral
Mammal
77 mg/kg, pregnant female 8-18 days
Fifty-seven
Reproductive toxicity
intraperitoneal injection
Mammal
52550 days after ug/kg, 9-15
Vitamin A deficiency is nutritional disorders caused by the lack of vitamin A. Children lack of vitamin A, the first night blindness, systemic epithelial tissue after skin degeneration and secondary infection. Due to inadequate intake, malabsorption, excessive consumption and metabolism etc.. This disease is more common in infants and young children.

Vitamin A performance

1, dark adaptation ability, night blindness, conjunctival dry and dry eye, corneal perforation appeared Bitot spots softening caused blindness.
2, mucosal epithelium.
3 growth retardation of suffering from respiratory infection.
4 taste, smell less, decreased appetite.
5 hair dry, rough skin, hair follicle hyperkeratosis, memory loss, mood irritability and insomnia.

Vitamin A utility

12 patients were treated with vitamin A eye drops, 83% effective results. Methods: vitamin A with 500 units, 1500 units / ml or ml preparations. Eye drops 4 times a day. Or through the Fraser Le brand of natural carotene vitamin A soft capsule. But would not recommend taking vitamin A, through the use of vitamin A - rich fruits and vegetables or taking beta carotene (precursor of vitamin A in the body automatically converted into vitamin A) and vitamin A.

Vitamin A Control points

 Lack of vitamin A Lack of vitamin A
Mild vitamin A deficiency due to malabsorption (such as intestinal diseases, stomach resection), metabolic abnormalities (have a fever) or excessive loss (Shen Yan) occurs, remove the pathogenic factors, given the rich in vitamin A food, such as liver, chicken liver, liver, milk, egg yolk, Hu Luobu, spinach, leeks, shepherd's purse, lettuce leaves, Lily or apricot fruit etc.. Given large doses of vitamin A, a daily dose of 20-30 million international units, if oral malabsorption can change the intramuscular injection, a month or so better, 3-4 months after recovery, use should pay attention to the large number of long-term use of vitamin A can cause hypervitaminosis A. If combined with other relevant supplementary vitamin deficiency.
Clinical studies have shown that vitamin A deficiency in area, annual or semiannual oral 300 thousand units of retinol oil droplets, can play a role in the prevention.
Too much vitamin A were common in the long-term use of vitamin A in children, the symptoms of this disease are skin changes (dry and rough skin), hepatomegaly and joint pain etc.. Just stop to give vitamin A, the symptoms will disappear.

Vitamin A Medical applications

With the deepening of clinical pharmacology research, people found that the effect of vitamin A on the treatment of various diseases.
Treatment of ulcer
Mainly for peptic ulcer, stress ulcer
The normal metabolism of vitamin A in the epithelial tissue of the stomach, and in epithelial tissue in the stroma of mucopolysaccharide synthesis, has a protective effect on gastric mucosa. Usage: after routine treatment of gastric ulcer in the process of adding vitamin A, each 50 thousand units, 3 times a day. With the blood vitamin A concentration decreased in patients with stress ulcer, oral or intravenous administration of large doses of vitamin A daily, 10 to 400 thousand units, can reduce the patient's stomach bleeding.
The treatment of benign breast tumor
Vitamin A compounds related to the regulation of cell growth and metabolism, promote the dissolution of cell membrane and lysosomal membrane, can inhibit the proliferation of cancer cells, promote cancer cells to normal tissue differentiation. Usage: 15 thousand units daily, oral, continuous medication for 3 months. Adjuvant treatment of measles in children due to the use of vitamin A increased, leading to acute vitamin A deficiency. A lot of vitamin A can reduce the mortality of children with measles.
Usage: on the basis of conventional therapy combined with vitamin A, 200 thousand units, the next day orally, once again, after reduction.
The treatment of flat wart
Flat wart is caused by HPV infection of skin neoplasm, cell maturation and the virus is related to the degree of keratinization. Vitamin A can be changed by the epidermal maturation process of infected virus particles within the nucleus of harmful effects, or inhibit the replication of virus particles, resulting in the extinction of warts. Usage: 50 thousand units of vitamin A every time, 3 times daily, orally, the general treatment of 1 ~ 4 weeks.
The treatment of menorrhagia
One of the important factors of menorrhagia is lack of vitamin A, this is because vitamin A is a coenzyme necessary for steroid hormones.
Usage: 25 thousand units of vitamin A every time, 2 times a day, and even served 15 days.
Prevention and treatment of premature infants with dysplasia
Application of mechanical ventilation in preterm infants can cause premature infants with bronchopulmonary dysplasia. Vitamin A can promote the damaged tissue to produce new ciliated and non ciliated columnar epithelial cells, has a protective effect on the respiratory tract.
Usage: vitamin A daily 1500 ~ 2800 units / kg, oral feeding.
Baby milk choke
Lack of vitamin A. Epithelial hyperkeratosis. Epiglottis causes the baby swallowing epiglottis insufficiency, thus choking occurred. There are reports of treatment of 45 cases of children with vitamin A2 (500 units) and Vitamin D (500 units) injection for 5-7 days. The symptoms were taken Cod Liver Oil, results 2-3 days 4-7 days to reduce choking, disappeared.
Squamous hair follicle keratosis, acne
Large doses of vitamin A. every day for 6 months 100 thousand. Has a good effect on acne vulgaris, but for a long time with easy to produce side effects. 3 other useful every 50 thousand units of vitamin A plus vitamin E100mg. treatment every day. Squamous keratosis follicularis In 35 cases the cure rate was 91.4%.
Effect of modified protein kinase
The data show that. Topical application of vitamin A acid. Some precancerous lesions. as Actinic keratosis Basal cell neoplasia.10% ~ 40% patients symptoms disappeared completely.
Children with recurrent respiratory tract infection
The lack of vitamin A, the main type of epithelial cilia of respiratory tract cilia disappeared, and the emergence of Squamous metaplasia . The researchers found that Recurrent respiratory tract infection The children, every two months, intramuscular injection of vitamin A, 6 consecutive times, compared with the control group, vitamin A injection group serum IgG increased significantly.
Dry skin is too much vitamin A
The human body needs nutrients can be obtained from the diet, not in favor of people eat health products. If you have to take care, should go to the hospital nutrition clinic doctor to determine what their lack of nutrients. In addition, do not blindly listen to the so-called "natural health products", because modern technology can make the molecular structure of synthetic product and natural product exactly the same.
Too much vitamin C can increase uric acid calcium, increase the risk of kidney stones.
Excessive intake of vitamin D will make people dizzy, itching, calcification.
Excessive intake of vitamin A will make the skin dry, vomiting and alopecia.
Excessive intake of protein, increase the burden on the kidney, may also make the body energy is too high, can lead to obesity, hypertension and hyperlipidemia and side effects.

Vitamin A Introduction

Vitamin A Market status

The global VA market after full competition in a long time, has been basically mature and stable. From 2003 to 2007, VA prices fluctuated between 85 yuan / kg to 140 yuan / kg. In 2008, the main raw material of VA beta ionone prices, BASF, DSM, Adisseo and other international giants have cut or even stop. In the interaction of rising costs and insufficient supply, the international market price of VA within a short period of time there was a substantial rise, but the volatility persistence in a relatively short time, in 2008 the annual average price of 140 yuan / kg. The second half of 2008, affected by the global financial crisis, users and dealers take inventory, user purchases fall, vitamin A prices began to fall. Since 2009, VA market price to maintain a narrow range of fluctuation, basically stable at 95 yuan / kg to 130 yuan / kg, in 2012 the annual average price of about 120 yuan / kg.

Vitamin A The modern history of discovery

In 1913, the United States Taiwan Weiss 4 scientists found, Cod-liver oil Can cure Dry eye , and purify a yellow viscous liquid from Cod Liver Oil in. In 1920, British scientists Manete will be officially named vitamin A. The official vitamin A as essential factors of nutrition, lack of cause Night blindness .

Vitamin A The common sense of life

1 beta Carrot In note
Because vitamin A can be Fat In storage, excessive intake Vitamin A Will cause the accumulation of toxic beta carotene, there is no such danger, even taking very large doses do not cause serious side effects, more than a day One hundred thousand International unit or 60 mg may make the skin turn yellow and orange, stop eating after return to normal skin. It is also used as a safe source of vitamin A. But the long-term use of beta carotene and lutein should supplement vitamin E and beta carotene, because will reduce the two levels in the human body.
2 food sources of vitamin A
yellow Fruits Such as yellow, orange and green vegetables contain animal fats such as beta carotene, contain some vitamin A in the liver and egg yolk. In addition, a good source of vitamin A is Cod Liver Oil, the Nordic wild cod liver oil is one of the best, because it is not only rich in vitamin A, vitamin D and DHA. In northern Europe, every day a spoon wild Cod liver oil Take in milk or soup has become the habit of public life. Pregnant women will also serve as an important source of COD Cod Liver Oil DHA and vitamin A, vitamin D.
3 recommended intake
Age
children
Man
woman
Pregnant woman
Lactation
1 to 3
One thousand
       
4 to 8
One thousand three hundred and twenty
       
9 to 13
Two thousand
       
14 to 18
 
Three thousand
Two thousand three hundred and ten
Two thousand and five hundred
Four thousand
19+
 
Three thousand
Two thousand three hundred and ten
Two thousand five hundred and sixty-five
Four thousand and three hundred

Age
children
Man
woman
Pregnant woman
Lactation
1 to 3
One thousand
4 to 8
One thousand three hundred and twenty
9 to 13
Two thousand
14 to 18
Three thousand
Two thousand three hundred and ten
Two thousand and five hundred
Four thousand
19+
Three thousand
Two thousand three hundred and ten
Two thousand five hundred and sixty-five
Four thousand and three hundred

Science China