For around 60% of the US population there is a genetic mutation that causes our body to have difficulties processing synthetic B12 which is used in most supplements and fortified foods. For that reason choosing an active vitamin B12 methylcobalamin supplement is the preferred choice. Food Sources of Vitamin B12
When it comes to assuring we maintain the correct levels of vitamin B12 and other nutrients food choices should be our first choice.
The good thing for most of us is that there are plenty of food sources rich in vitamin B12. It's true most of them come from meat, dairy and eggs, but there are a few key sources perfect for vegetarians.
First we have nutritional yeast. Nutritional yeast is a fortified food that has many beneficial nutrients including vitamin B12. Nutritional yeast has a cheese-like flavor that makes a nice addition to many recipes, or simply as a seasoning for popcorn.
Second we have purple laver, better known as nori by many. Nori is an algae eaten mainly in Asian parts of the world. The good news is that eating only 4 grams of dried nori gives you the daily requirement of B12.
The third option is mushrooms. Some mushrooms, particularly the shiitake mushroom contain vitamin B12. While mushrooms do contain B12 it is not likely you can get enough B12 from just mushrooms alone. But mushrooms can still be a good supplemental source of B12 to add to your diet.
While there are food sources of B12, even for vegetarians, supplementation might be a good option for all of us even if we do eat B12 rich foods.
Picking the right form of B12, an active methylated B12, can help keep B12 levels in the optimal range.