Like all of the B vitamins, Vitamin B-12 is a water-soluble vitamin, and that means that the body does not manufacture any of it on its own. The only way to get the vitamin is through the foods you eat. Unfortunately, as men and women get older, years of poor diet, consumption of alcohol, smoking, and diseases or illnesses might prevent the body from being able to absorb sufficient B-12.
What Does Vitamin B-12 Do in Your Body?
All of the B vitamins are crucial to the mechanisms of your body on a cellular level. If you are low on one or multiple B vitamins, chances are you will feel run down and tired (at the very least) as the B vitamins directly activate metabolic processes that allow you to gain energy from the foods you eat.
Vitamin B-12, in particular, acts like a key for a number of very important processes to take place that play vital roles in your energy levels, including red blood cell formation, proper nervous system function, DNA synthesis, and more.
There are four types of Vitamin B-12—three of which are critical to health maintenance:
- Methylcobalamin is the most active form of Vitamin B-12, the main key for cellular and metabolic processes. Methylcobalamin is the form of B-12 that you find naturally occurring in the foods you eat, and it is the most easily absorbed and utilized by your body.
- Hydroxocobalamin is another naturally occurring form of B–12 that is found in the foods you eat. This form of B-12 easily converts into methylcobalamin in the body. If you have a serious B-12 deficiency that requires B-12 injections, it will be hydroxocobalamin in the syringe. Fun fact: hydroxocobalamin is also used to counteract cyanide poisoning.
- Adenosylcobalamin is the least stable form of B-12 and occurs naturally in foods that have B-12.
Dietary Sources of B-12
Vitamin B-12 is available only through animal sources like beef, fowl, fish, dairy, and eggs. For this reason, vegans and vegetarians are more susceptible to B-12 deficiency and need to supplement with B-12—preferably with products that contain methylcobalamin. For those who have gut health problems and cannot easily digest animal products, B-12 deficiencies are also common.
How Is Vitamin B-12 Absorbed?
B-12 is absorbed through the intestines after your stomach produces a protein called intrinsic factor. If you don’t produce enough intrinsic factor, you may end up with a B-12 deficiency. Gut health, therefore, is crucial to your absorption rates of B-12. Antibiotics; chemical food additives like MSG; mercury poisoning from dental fillings, farmed fish and shellfish, and water; a diet high in refined flours, sugars, and fats; high alcohol consumption; smoking; and certain diseases or illnesses can all harm your gut health and reduce or prevent B-12 absorption.
Are You Low on Vitamin B-12?
With 40% of the population suffering from some degree of B-12 deficiency, chances are you or someone you know needs a B-12 boost. The National Health and Nutritional Health Examination Survey estimates that 3.2% of people over 50 suffer from a seriously low level of B-12, while 20% of people 50 and older are borderline deficient!
Deficiency symptoms can range from fatigue and weakness to serious depression, memory loss, loss of smell or taste, pins and needles in the arms and legs, and more.
Supplementing with Vitamin B-12
As we’ve discussed above, the preferred form of Vitamin B-12 is methylcobalamin. For those over 50—and especially for those 50 or older who are vegetarian or vegan—a liquid methylcobalamin supplement that you drop under the tongue is the most effective. Remember that the B vitamins work most effectively when they work together, so you need to be getting all your B vitamins every day.
Remember also that any good quality supplements only benefit you if you are also eating a well-balanced diet and avoiding sugar and junk foods.