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Vitamin B12 Therapy at Wonder Medicine

Updated: Nov 24, 2023

Vitamin B12 Deficiency

Vitamin B12 is the largest and most complex vitamin. It is an essential water soluble vitamin found in the food we eat (mainly animal products). It is vital for human growth, development, and is involved in the metabolism of every cell in the human body. Vitamin B12 can also be found as a supplement and as an injection. It is believed that vitamin B12 deficiency affects up to 15% of the general population, particularly adults and the elderly. Symptoms of deficient vitamin B12 in adults include: anemia, fatigue, weakness, constipation, and loss of appetite. Deficient levels can also lead to neurologic changes such as numbness and tingling in the hands and feet, difficulty maintaining balance, depression, confusion, and poor memory.

There are four main reasons for vitamin B12 deficiency:

1) pernicious anemia

2) hypochlorhydria or achlorhydria- resulting in reduced levels of stomach acid

3) those with intestinal disorders

4) mainly vegetarian or vegan diets.

These disorders, along with prolonged antacid therapy, inhibit the individual from properly absorbing vitamin B12 through their gut.

Luckily, vitamin B12 is available as an injection as cobalamin, hydroxocobalamin, methylcobalamin, and adenosylcobalamin. A simple injection once or twice a month can greatly improve an individual’s B12 levels and easily resolve deficiency symptoms.

But that’s not all, recent studies have found B12 injections to have other health benefits.

Vitamin B12 and Increased Semen Quality

A 2017 article reviewed 23 recent studies on vitamin B12 and semen quality. The results stated that B12 increased sperm count, enhanced sperm motility, and reduced sperm DNA damage. They found that plasma vitamin B12 concentrations were lower in infertile men compared to fertile. That being said, vitamin B12 increased sperm count by 50% in men who had a decreased sperm count, but was not able to increase sperm count in men that had no semen in their sperm. The studies found that antioxidant treatment including vitamin B12 was found to improve sperm vitality, motility, and DNA integrity. As a result, vitamin B12, typically at the normal or therapeutic doses, is vital for adequate semen quality.

Vitamin B12 and Lactation

Vitamin B12 is an essential vitamin for newborns and growing infants. They get most of their vitamin B12 through their mother’s breast milk. Deficiencies in vitamin B12 can lead to failure to thrive, movement disorders, developmental delays, convulsions, abnormal hair and skin color, and megaloblastic anemia. Vitamin B12 levels are highest in the first four weeks after delivering, and then slowly decrease after. A study was conducted on mothers in India with low B12 levels. They were given a single B12 injection and their breast milk B12 levels were measured. After their injection, their breast milk B12 levels nearly doubled. Their B12 levels remained higher than normal for about two days, then returned to baseline 3-5 days after the single dose.

In another study, a single B12 injection was given to mothers with breastfeeding infants with known vitamin B12 deficiency. Within 5 to 8 days after the injection, the infants experienced significantly increased hemoglobin levels, improved mental status, improved skin pigmentation, and reduced amount of tremors.

Vitamin B12 and Cardiovascular Disease

Cardiovascular disease is on the rise in the United States and is the most common cause of death. Major risk factors include: high blood pressure, elevated low-density lipoprotein (LDL) levels, decreased high-density lipoprotein (HDL) levels, obesity, diabetes, and elevated homocysteine levels. Now what’s homocysteine? Homocysteine is a sulfur-containing amino acid that is normally present in blood. Homocysteine works by inhibiting metabolites and increasing inflammation. Elevated homocysteine levels have been thought to promote a number of heart conditions and have been linked to coronary heart disease and stroke.

Vitamin B12, along with folic acid and vitamin B6, has been shown to aid in homocysteine metabolism. Without sufficient vitamin B12, homocysteine levels can rise. Individuals with vascular disease who took vitamin B12 along with folic acid and a multivitamin, saw reduced homocysteine levels.

Vitamin B12 and Cognitive Function

Remember homocysteine? Well, it plays a role in cognitive function as well. A deficiency in vitamin B12 results in an accumulation of homocysteine in the blood and has been thought to decrease levels of substances that are needed to metabolize neurotransmitters. Recent studies have shown positive associations between increased homocysteine levels and the incidence of both Alzheimer’s disease as well as dementia. Cognitive decline, Parkinson’s disease, and multiple sclerosis have also been associated with decreased vitamin B12 levels. More research is needed in these areas to determine vitamin B12’s role with these conditions.


Vegans, vegetarians, and the elderly are at the highest risk of vitamin B12 deficiency. More and more studies are being conducted to show the benefits of vitamin B12. Many of my patients swear that B12 gives them increased energy, allowing them to participate in more physical activity and aides their ability to concentrate. I personally have felt the benefits of monthly vitamin B12 injections and recommend it to anyone that is feeling mentally foggy, fatigued, or is looking to try something new in their health routine. Wonder Medicine offers cobalamin and methylcobalamin injections. If you suffer from any of the conditions listed above and would like to try vitamin B12, give us a call or click here to schedule an appointment!


Karlee Brandenburg, RN-BSN

Wonder Medicine’s Longevity and Performance Program improves your lifespan and healthspan with a research-driven proactive program that focuses on the big picture of your health so you can perform at your highest potential.


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