What Should we Eat for B12?

It seems that everyone is talking about vitamin B12, right?

As a dietitian, I highly recommend my clients to take vitamin B12 and D. Vitamin B12 deficiency can have irreversible side effects. I also recommend vitamin D, unless they are living above or below the equator by 37 degrees (depending on individual health circumstances).

As for vitamin B12, despite our intake, we facing insufficient intrinsic factor and gut bacterial diversity. Along with

Vitamin B12, like most vitamins, come in many different forms. B12 has the mineral cobalt and therefore, are referred to the group of “cobalamins”: Methylcobalamin and 5-deoxyadenosylcobalamin ("Office of Dietary Supplements - Vitamin B12", 2019).

Our parietal cells (located in the stomach), secret Intrinsic Factor, which is a glycoprotein, and is necessary for B12 secretion and absorption. Yes, we can make our own B12 as well! However, due to decreases in Intrinsic Factor, with modern lifestyle, and in our food supply, we need to supplement with B12.

The picture below summarizes how important B12 is for our neural, genetic and circulatory system. It used to be argued that we needed to animal protein for B12, yet not only is that not correct, as there are a wide range of supplements available.

Image 1

Due to our sanitized, modern world we do not get B12 from the soil our produce grows on, or livestock feeds from. It is crucial to supplement with B12, especially if you are consuming a plant based diet. In addition, some clients tell me that their B12 levels come back in the average values. This is where I suggest caution: a diet high in folate can mask a vitamin B12 deficiency.

The recommended daily allowance of 2.4 μg/d can be met with supplements, and in patients with food-bound malabsorption, 40 μg/d to 80 μg/d of oral crystalline vitamin B12 can be administrated for 30 days, and increase if biochemical signs of deficiency are not reversed (Johnson, 2008). With age, we have decreased B12 absorption, and for those 65+ who eat plant-based diets, supplementation can be increased to could probably be increased up to 80 μg/d of cyanocobalamin each day.

If you want to follow a plant based diet and not take B12 supplements, we can get sufficient B12 from fortified food, yet we would have to eat three servings a day of foods each providing at least 75 percent of the Daily Value (on the Nutrition Facts label) for the United States ("Vitamin B12: The Latest Research | NutritionFacts.org", 2019). Most of us find it easier to guarantee our intake with a supplement.

Our ancestors get by with eating bugs, dirt, and feces, but I would suggest fortified food and/or supplements :)

References:

Johnson, M. (2008). If High Folic Acid Aggravates Vitamin B12 Deficiency What Should Be Done About It?. Nutrition Reviews, 65(10), 451-458. doi: 10.1111/j.1753-4887.2007.tb00270.x

Nutrition Only in Animal-Based Foods. (2019). Retrieved 25 October 2019, from https://www.carlagoldenwellness.com/2015/02/05/nutrition-only-in-animal-based-foods/

Office of Dietary Supplements - Vitamin B12. (2019). Retrieved 25 October 2019, from https://ods.od.nih.gov/factsheets/vitamin%20B12-HealthProfessional/

Vitamin B12: The Latest Research | NutritionFacts.org. (2019). Retrieved 25 October 2019, from https://nutritionfacts.org/topics/vitamin-b12/