Vitamin B12 Foods
Vitamin B12 is found in both animal and plant sources. (3)
3.5 oz of clams contains 84 mcg (1) (3)
3 oz of mackerel contains 16.2 mcg (4)
3 oz of herring contains 11.1 mcg (4)
3 oz of tuna, bluefin contains 9.4 mcg (4)
3 oz of sardines contains 7.6 mcg (3),(4)
3 oz of trout contains 5.4 mcg, (6.4 mcg) (1) (3)
1 serving of 100% fortified breakfast cereal contains 6 mcg (1)
3 oz of salmon contains 4.9 mcg (1)
3 oz of pollock contains 3.1 mcg (4)
4 oz of tuna contains 2.66 mcg
4 oz of lamb contains 2.51 mcg
2.5 oz of tuna fish, canned contains 2.5 mcg (1)
4 oz of scallops contains 2.44 mcg
3 oz of 80% lean ground beef contains 2.42 mcg (3)
3 oz of tuna, yellowfin contains 2 mcg (4)
3 oz of tilapia contains 1.6 mcg (4)
3 oz of beef contains 1.5 mcg (1)
fortified soy milk, chocolate contains 1.7 mcg (1)
6 oz of nonfat plain Greek yogurt contains 1.3 mcg (1) (3)
3 oz of tuna, white contains 1 mcg (4)
1 cup of yogurt contains 0.91 mcg
3 oz of cod contains 0.9 mcg mcg (4)
1 slice of Swiss cheese contains 0.9 mcg (1)
3 oz of anchovies contains 0.8 mcg (4)
1 chicken egg contains 0.6 mcg (1) (3)
3 oz of ham contains 0.6 mcg (1)
4 oz of cow’s milk contains 0.55 mcg
4 oz of turkey contains 0.42 mcg
4 oz of chicken contains 0.39 mcg
3 oz of roasted chicken breast contains 0.3 mcg (1)
1 oz of cheese contains 0.24 mcg
1 cup of Crimini mushrooms contains 0.07 mcg
1/4 cup of shredded Colby cheese contains 0.2 μg (2)
liverwurst
blue mussels
red meat
fish
shellfish
soya
nut milks
camel fat
butter
organ meat (3)
lamb liver (3)
beef liver (3)
veal liver (3)
lamb kindeys (3)
veal kindeys (3)
beef kidneys (3)
tempeh (4)
algae (4)
seaweed (4)
chlorella (4)
fortified foods (4)
nori (5)
Broccoli (5)
asparagus (5)
some mushrooms (5)
Fortified Foods
1 tbsp of fortified nutritional yeast contains about 4 mcg (3), (5)
Bioavailability
It is estimated that the bioavailability of vitamin B12 from fish is about 42%. (4)
Heat/Cooking
Cooking of fish can significantly decrease its vitamin B12 content. For instance, according to a study, grilling, boiling, frying, steaming, or microwaving of herring decreased its vitamin B12 content up to 62%. (4)
According to another study, about 30-40% of vitamin B12 of fish is lost during microwave heating. (4)
Time
The best time to take vitamin B12 supplements is at breakfast. (5)
Resources
1. https://www.health.harvard.edu/staying-healthy/the-a-list-for-vitamin-b-12-sources
2. https://www.eatthismuch.com/food/nutrition/colby-cheese,11/
3. https://www.sportskeeda.com/health-and-fitness/is-vitamin-b12-only-available-animals-5-best-sources-b12
4. https://lazyplant.com/fish-b12/
5. https://lazyplant.com/b12-vegan-foods/
