Another excellent source of vitamin B12 is sardines. Just 3 ounces of these cold water fish will provide you with 6.6 mcg of vitamin B12, which is more than 100 percent of the daily recommended intake. Not only are sardines an excellent source of vitamin B12, but they are also jam-packed with omega 3 fatty acids. Extensive scientific research has found that the omega 3 fatty acids in sardines offer tons of different health benefits, including increased heart health, decreased inflammation and even reducing the side effects of asthma. Believe it or not, sardines do taste good as a pizza topping; however, you can also de-bone them, put them in a food processor and put them in a salad dressing to disguise the flavor.