How do you know if you are deficient in B12?
A simple blood test can diagnose a vitamin B12 deficiency.
For example, your doctor might recommend a complete blood count (CBC), a homocysteine test, or a methylmalonic acid (MAA) test.
The most important step, however, is to visit a doctor who has experience in diagnosing and treating B12 deficiencies.
Foods high in vitamin B12
While you can take B12 supplements, most are Cyanocobalamin, which is man-made and not as bioavailable as B12 found naturally in foods. Here is a list of foods that contain significant amounts of B12: Beef, animal liver and clams, fish like sardines and tuna, meat, eggs, milk, and other dairy products.
For vegetarians and vegans, it takes a conscious effort to increase your intake. Here is a list of vegan foods with lesser known amounts of B12:
- Algae – such as Spirulina and Chlorella
- Seaweed – such as Nori or Laver
- Nutritional yeast – a form of deactivated yeast (Saccharomyces cerevisiae)
- Wheatgrass Juice – from freshly sprouted leaves
- Legumes Sprouts – like moong, peas, lentil
- Root Vegetables – like carrots, radish and turnips
- Buckwheat – such as noodles or porridge
- Mushrooms – Black trumpet and Golden Chanterelle contain higher levels of B12
- B12 fortified foods – such as breakfast cereal, non-dairy milk and nutrition yeast
The recommended daily amount (RDA) of vitamin B12 increases as you get older. It’s recommended that vegans take more than the RDA of B12, to compensate for lower bioavailability of supplements and lack of animal sources in their diets.
The best form of supplemental B12 is methylcobalamin, which is naturally occurring and most readily absorbable.
See our recommended methylcobalamin source below.
Keep in mind that your body may only absorb 50% of the vitamin B12 it ingests. What’s more, certain medical conditions, such as gut inflammation can impede B12 absorption. So it’s important to monitor your levels as you adjust your diet or begin supplementation.
If you have type 2 diabetes, and take medication, have your B12 regularly checked to ensure you’re getting enough.