what are the benefits of Vitamin-A

                           Vitamin-a is very essential for growth and development and good vision , it is provide resistance to infection and toxins .Vitamin-a consists of retinol , retinal , retinoic acid and many carotenoids and beta-carotene.This is very essential for covering of internal and external cells of the body . Vitamin-A supplementation enhance the resistance and reduce the mortality from some diseases . 

                                                                  image from u.s. department of agriculture

 Dietary reference intake recommended daily allowance of vitamin-a :

                          Age group                    Intakes(ug)

                

                           Infants

                           0-6 months ------------ 400 -600

                          7-12 months------------- 500-600

                           Children

                           1-3 years ---------------- 300-600

                           4-8 years ---------------- 400-900

                           Males

                            9-13 years -------------- 600-1700

                           14-18 years -------------- 900-2800

                           19-70 years -------------- 900-3000

                          Females

                            9-13 years --------------- 600-1700

                           14-18 years --------------  700-2800

                           19-70 years --------------- 700-3000

                           pregnancy 

                             < 19 years ---------------- 750-2800

                           19->50 years -------------- 770-3000

             

                           Lactation

                             < 19 years ----------------1200-2800

                           19->50 years --------------1300-3000

Food sources for Vitamin-A :

1.                Liver ( beef ,fork, fish) contain 6500 ug (822%)
2.                 Sweet potato contain 709 ug (89%)
3.                  Carrot contain 835 ug (104%)
4.                 Broccoli contain  800 ug (89%)
5.                 Tomatoes contain 42 ug (5%)
6.                 Apricot contain 96 ug ( 12%)                         
7.                 Pumpkin contain 426 ug (53%)
8.                Butter contain 684 ug (86%)
9.                 Peas contain 103 ug
10.                 Dried marjoram contain 403 ug
11.                 Peaches contain 108 ug 
12.                 Dandelion greens contain 508 ug
13.                  Egg contain 149 ug (19%)
14.                  Papaya contain 47 ug (6%)
15.                  Mango contain 54 ug (7%)
16.                 Milk contain 46 ug (6%)
17.                  Kale contain 500 ug (63%)
18.             Spinach contain 469 ug (59%) .          

                 ( data taken from usda national nutrient data base) 

Health benefits of vitamin-a:

                 Vitamin-a is very vital for good vision , vitamin-a contain retinoic acid is used in the treatment of dermatological problems . For the treatment of skin diseases 13-cis retinoic acid drug is used, this drug reduce the bacteria on the skin surface but this drug has some side effects before taking its requires doctor advise . 
                 It is contain retinoic acid is very helpful for teeth development , maintain skin health and bone growth , retinoic acid is very essential for synthesis of glycoprotein , this type of glycoprotein prevent corneal ulcers and vitamin-a is need for formation of red blood cells in the bone marrow .
                 Vitamin-A acting best anti-aging , and it is remove night blindness and also anemia .Vitamin-a prevent some cancers also.
                  It is  protects our body against some diseases and increase body immune capacity, it is very essential for female reproduction and embryonic development , vitamin-a eliminate free radicals and acts as antioxidant agent.

Toxicity of vitamin-a:

                   Excessive consumption of vitamin-a leads to kidney failure , reduced appetite, vomiting , nausea , increase muscle and abdominal pain , increase hair fall , fever , fatigue , weight loss and diarrehea , increased the risk of bone fracture , skin and hair color changes , arise double vision in young children , increase unconsciousness , liver damage .