Vitamin B12, or cobalamin, is an essential vitamin, meaning that the body needs it to function properly. The body cannot make B12 on its own, so it is your responsibility to obtain it via dietary sources or supplements. This vitamin plays a critical role in the formation of red blood cells, cell metabolism, and the production of DNA. It also aids with healthy nerve function and even though it is essential for optimal health, it’s estimated that 6% of the U.S. population younger than 60 years is B12 deficient.
How Much Vitamin B12 Do You Need?
Your B12 needs change depending on your age range. Like most other nutrients, babies and children require less B12 on a daily basis than older adults. Below, you’ll find a breakdown for the recommended daily intake (RDI) of B12 in micrograms (mcg):
- Birth to 6 months: 0.4 mcg
- 7-12 months: 0.5 mcg
- 1-3 years: 0.9 mcg
- 4-8 years: 1.2 mcg
- 9-13 years: 1.8 mcg
- 14-18 years: 2.4 mcg
- 19 years or older: 2.4 mcg
Keep in mind that these recommendations are based on amounts that you need to avoid deficiency. The average adult may need more or less B12 to maintain optimal levels. For example, to achieve healthy blood levels of B12, research suggests that daily intake levels of B12 should reach 5.94 mcg for men and 3.78 mcg for women over the age of 20. During pregnancy and breastfeeding, needs for vitamin B12, and most other nutrients, increase. Vitamin B12 is vital for proper fetal growth, so pregnant women require 2.8 mcg per day.
What Causes B12 Deficiency?
There are several factors, some of which are out of a person’s control, that contribute to vitamin B12 deficiency. According to research, the three primary causes of B12 deficiency are:
- Autoimmune issues: Pernicious anemia is a type of autoimmune condition that makes it hard for the small intestine to properly absorb B12, leading to low levels.
- Low dietary Intake: Vitamin B12 is primarily in animal-based foods, including meat, fish, dairy, eggs, and poultry. For this reason, people who follow strict vegan and vegetarian diets are more at risk for deficiency. It tends to take a couple years of following these diets to become deficient, which is why experts encourage supplementation.
- Malabsorption: Some people aren’t able to properly absorb B12 because of intestinal damage or surgery. People who have had gastric bypass surgery or part of their bowel removed may be at risk for B12 deficiency.
- Long-term use of certain medications: Certain medications, especially ones that lower blood sugar or treat acid reflux, can interfere with B12 absorption and ultimately cause B12 deficiency.
What Are Symptoms Of B12 Deficiency?
It should be noted that B12 deficiency is not very common in the U.S., but it is more common in the Indian subcontinent, Mexico, and Central and South America. Selected areas of Africa also have an increased risk of B12 deficiency. Deficiency can go undetected in many people, which is why bloodwork is necessary to determine your levels. The most common symptoms of this B12 deficiency include:
- Fatigue
- Pale skin
- Dry lips
- Breathlessness when engaging in activity
- Pale conjunctiva (tissue that lines the inside of the eyelids)
- B12 deficiency can also lead to neurological symptoms like:
- Dizziness
- Headaches
- Difficulty walking
- Memory problems
- Tingling in the extremities
Risk Factors
Some people have a higher risk than others of developing vitamin B12 deficiency. Different factors like underlying medical conditions and age can influence susceptibility. Other factors, like long-term use of certain medications, can increase the risk of B12 deficiency. Being pregnant or breastfeeding can also put people at a higher risk for deficiency. The reason for this is because needs for B12 increase during these times. Abusing alcohol and drugs like methamphetamine can increase the risk for B12 deficiency. More often than not, poor dietary intake leads to B12 deficiency, but alcohol and other drugs can lead to decreased B12 absorption.
