Liver is also one of the highest sources of Vitamin A which is good for the eyes.
http://www.livestrong.com/article/2...-in-beef-liver/
Liver has 6,000 times more Vitamin A, than carrots.
Look at the percentages below:
Vitamin A is found naturally in many foods:
cod liver oil (30000 μg)
liver (turkey) (8058 μg 895%)
liver (beef, pork, fish) (6500 μg 722%)
liver (chicken) (3296 μg 366%)
dandelion greens (5588 IU 112%)[18]
sweet potato (961 μg 107%)
carrot (835 μg 93%)
broccoli leaf (800 μg 89%) – According to USDA database, broccoli florets have much less.[19]
broccoli florets (31 μg 3%)
butter (684 μg 76%)
kale (681 μg 76%)
spinach (469 μg 52%)
pumpkin (400 μg 41%)
collard greens (333 μg 37%)
Cheddar cheese (265 μg 29%)
cantaloupe melon (169 μg 19%)
egg (140 μg 16%)
apricot (96 μg 11%)
papaya (55 μg 6%)
mango (38 μg 4%)
pea (38 μg 4%)
milk (28 μg 3%)
tomatoes
Seaweed
Note: Data taken from USDA database.[20] Bracketed values are retinol activity equivalences (RAEs) and percentage of the adult male RDA, per 100 grams of the foodstuff (average).
Conversion of carotene to retinol varies from person to person and bioavailability of carotene in food varies
Source:
https://en.wikipedia.org/wiki/Vitamin_A