You’re shopping for vitamin B12 or cobalamin. You walk down the supplement aisle of any drug store or browse your favorite online provider and see numerous vitamin B12 options.
You see cyanocobalamin, adenosylcobalamin, and methylcobalamin-based vitamin B12 supplements. Hydroxycobalamin is there, too, and different combinations of these options are available.
These are unfamiliar terms to you, and you’re unsure which formulation to purchase. Notwithstanding, you want the best value for money and quick results.
This article aims to provide you with a comprehensive understanding of vitamin B12 supplements. We’ll guide you on choosing the right one, explain the various health benefits of cobalamin, and much more.
What are the forms of vitamin B12?
There are four principal kinds of vitamin B12 on the supplement shelf: methylcobalamin (MeCbl), cyanocobalamin (CNCbl), hydroxycobalamin (OHCbl), and adenosylcobalamin (AdCbl).
Methylcobalamin, adenosylcobalamin, and hydroxycobalamin are the natural forms, while cyanocobalamin is the synthetic form of vitamin B12.
Methylcobalamin
Methylcobalamin is an active form of vitamin B12, so your body can readily absorb it. This form functions the same way as the B12 naturally occurring in human physiology. It is readily available in poultry, fish, meat, eggs, and milk.
Adenosylcobalamin
Adenosylcobalamin is another active form of cobalamin. Like methylcobalamin, it’s equally available in food sources.
This form of vitamin B12 is like the yin to the yang of methylcobalamin, as the body uses both together in critical metabolic reactions.
Adenosylcobalamin is essential for running the mitochondria, the energy headquarters of cells.
Hydroxocobalamin
Hydroxocobalamin is primarily manufactured in the lab. However, the body can naturally produce it in the digestive tract during food metabolism.
Doctors typically prescribe it to treat pernicious anemia, a condition caused by vitamin B12 deficiency.
Cyanocobalamin
Cyanocobalamin is perhaps the most popular form of vitamin B12 in dietary supplements in the United States.
It’s the synthetic form of cobalamin, but the body readily converts it to methylcobalamin and adenosylcobalamin, the active forms of B12.
The cyano denotes the presence of a cyanide molecule. You may be wondering: “Isn’t cyanide poisonous?” Yes, cyanide is poisonous, but the quantity in the supplement is minuscule and not enough to cause any short effects.
However, long-term consumption may lead to cyanide deposits in the body.
What is the best form of vitamin B12?
There is no clear evidence supporting the idea that one form of vitamin B12 is more effective than the others. However, cyanocobalamin has safety concerns, including the increased risk of cyanide accumulation in the body.
Multiple research studies show that all commercially available forms can help increase the body’s vitamin B12 levels.
One study examined the efficacy of vitamin B12 supplementation in 158 children between 0 and 3 years old who were vitamin B12 deficient, that is, had serum or blood vitamin B12 levels of less than 300 ng/L.
The researchers divided the subjects into three groups, each given one of the following forms of vitamin B12: intramuscular cyanocobalamin, sublingual methylcobalamin, and oral cyanocobalamin.
The results showed that average serum levels of vitamin B increased to more than 300 ng/L for all the participants, leading the authors to conclude that methylcobalamin was as effective as cyanocobalamin.
Another study treated subjects with a 1000 mcg dose of sublingual methylcobalamin every day for one week before reducing the dose in the following weeks to once daily every other day, twice a week, and once a week within a four-week period.
The before-and-after results show that the average vitamin B12 levels increased from 199 pg/mL to 684 pg/mL.
There is little research that directly compares the four forms of vitamin B12. According to the National Institutes of Health (NIH) Office of Dietary Supplements (ODS), “no evidence indicates that absorption rates of vitamin B12 in supplements vary by form of the vitamin.”
This is because the body must remove the supporting molecule ((hydroxyl, methyl, cyano groups, and adenosyl) from the cobalamin molecule.
That said, there are medical concerns regarding the use of cyanocobalamin. The worry is that heavy cyanocobalamin usage may lead to cyanide accumulation in the tissues. The risks are significantly higher in smokers who readily have thiocyanate in their blood.
How do I choose the right vitamin B12 supplements?
When considering the proper vitamin B12 supplements, look out for the following factors:
Third-party testing
There is not enough oversight in the supplements industry. So, verify that the manufacturer's claims have been independently tested and certified. This verification provides added security that you’re consuming a safe product.
Contains the B12 forms found in food sources
Opting for a supplement that mirrors the B12 forms found in food sources can give you confidence in your choice. This ensures that your body gets a supplement that is more easily absorbed and utilized. Does not have contaminants like sugar and alcohol
High dosage
According to Dr. Suzanne Salamon, associate chief of gerontology at Harvard-affiliated Beth Israel Deaconess Medical Center, “I may recommend an over-the-counter B12 pill of 1,000 micrograms daily if B12 is borderline low.”
Uses the natural form
If the supplement uses the natural form, particularly methylcobalamin and avoids cyanocobalamin, which has been linked to the increased risk of impaired kidney function.
Your condition
People suffering from pernicious anemia will require B12 injections, as over-the-counter supplements will not work for this condition. Pernicious anemia is a condition in which the body cannot adequately absorb vitamin B12.
Is vitamin B12 supplement safe?
Vitamin B12 supplements are generally safe, even in high dosages for healthy people. However, people with underlying conditions like renal disease must be wary of the form of vitamin B12 they consume.
Cobalamin is so safe that the US Food and Nutrition Board has not set any tolerable upper intake level (UL) for the vitamin.
The UL is the highest dose of a substance you’ll consume that will not negatively or adversely affect your health. However, beyond this level, the patient may encounter serious side effects or damage to their health.
Vitamin B12 is safe primarily because of two key factors, including:
- B12 is a water-soluble vitamin. As such, you’ll pass out excess B12 via urine.
- The body only absorbs a small amount of vitamin B12 at a time.
These two factors make cobalamin have a low potential for toxicity.
Does the vitamin B12 supplement have side effects?
The doses from over-the-counter vitamin B12 supplements do not generally lead to any notable side effects.
However, large doses given via drips and injections may cause relatively mild side effects like headache, vomiting, nausea and serious complications such as blood clots or cancer.
The severe side effects like blood clots or cancer are, however, infrequent.
Does vitamin B12 interact with other medications?
Drugs for gastroesophageal reflux disease, peptic ulcer disease, high cholesterol, and type 2 diabetes mellitus, like Metformin, are examples of medications that decrease the absorption of vitamin B12 from food.
Drugs in the proton-pump inhibitors (PPI) class work by reducing the production of stomach acid. The body needs stomach acid to absorb vitamin B12.
Hence, taking drugs like omeprazole and esomeprazole used to treat gastroesophageal reflux may impair your ability to absorb vitamin B12 supplements.
Research suggests that long-term use—more than two years of continuous use—of PPIs can lead to lower serum levels of vitamin B12.
Peptic ulcer drugs like cimetidine and famotidine may also potentially reduce the amount of vitamin B12 absorbed from food.
Other drugs or substances that potentially decrease your body’s ability to absorb cobalamin include nitrous oxide (laughing gas), some antibiotics like chloramphenicol and neomycin, and Metformin.
In particular, nitrous oxide inactivates B12 in your body, thus making it impossible for the body to perform some of its essential functions.
Who needs vitamin B12 supplements?
Certain groups require vitamin B12 supplements more than others. These groups include:
Vegan and vegetarians
Vegans, vegetarians, and those on a predominantly plant-based diet are at risk of vitamin B12 deficiency. This is because animal-based foods are the only source of cobalamin.
A comparison from a study of 65,429 men and women containing meat eaters and plant eaters found that the former group had an average daily cobalamin intake of 7.2 µg, compared to 0.4 µg in the latter group.
According to the Food and Nutrition Board (FNB) at the National Academies of Sciences, Engineering, and Medicine, the recommended dietary allowance (RDA) for adults over 19 is 2.4 mcg for both males and females.
Based on this information, individuals on a vegan diet only get 16.67% of the required daily cobalamin intake, hence why this group is at risk of being deficient.
Vegans and vegetarians can opt for vitamin B-12 fortified foods and dietary supplements to reduce their risk of deficiency.
Offsprings of vegan women
Exclusively breastfed infants from vegan-vegetarian women may develop vitamin B12 deficiency. The severity of the infant’s deficiency is directly associated with how severe the mother’s deficiency is or if pernicious anemia is the root cause of the mother’s deficiency.
When left untreated, vitamin B12 deficiency can lead to severe complications like neurological damage and anemia. Research shows that vitamin B12 supplementation can correct this trend when detected early.
Researchers in a study divided forty-seven children aged between 1 month to 17 years) into two major groups - 1-20 months and 6-17 years.
Each group was further divided into two based on the duration of treatment received. One group received vitamin B12 supplementation for four months and the other for eight months.
The progression of the treatment was as follows:
- Week one: 1000 μg oral vitamin B12 daily
- Week two and three: 1000 μg oral vitamin B12 every other day
- Week four and five: 1000 μg oral vitamin B12 two days per week
- Week six and onwards: 1000 μg oral vitamin B12 once per week
The researchers found that all the groups responded well to the treatment, significantly increasing vitamin B12 levels. That said, the first group, 1-20 months old, responded better to the treatment.
Why Not Natural offers sublingual organic Vitamin B12 liquid drops perfect for kids above two years. It comes with a graduated dropper for easy dosing.
Older adults
Older adults over 50 are at risk of vitamin B12 deficiency simply because the body produces less stomach acid as we age.
And as previously mentioned, stomach acid is essential in extracting vitamin B12 from food sources. The prevalence of vitamin B12 deficiency among older adults over 60 years old is around 20%.
Some of the common underlying conditions that lead to being B12 deficient in this population include atrophic gastritis (affects 8% to 9% of adults aged 65 and older), pernicious anemia affects (15% to 25% of adults aged 65 and older), and Helicobacter pylori infection.
Pregnant and lactating women
During pregnancy, it is normal for pregnant women to experience lower serum vitamin B12 levels. However, the situation reverses post-delivery.
Vitamin B12 deficiency in pregnant women poses significant risks for the child, including anemia, neural tube defects, fetal development delays, and potential loss of the pregnancy.
Extensive research has consistently shown a remarkably high prevalence of vitamin B12 deficiency in pregnant women.
In one study of 522 women, all with less than 20 weeks gestational age, the researchers found that 19% of the subjects had vitamin B12 deficiency and 40% had marginal deficiency.
Another study of 800 women up to 15 weeks pregnant found that 71% had low or marginal vitamin B12 deficiency status. In Europe, the prevalence of cobalamin deficiency in pregnant women ranges from 18% to 43%.
Vegan mothers are particularly at risk of developing vitamin B12 deficiency during pregnancy. Women who eat meat but not enough of it are also at risk.
According to the Office of Dietary Supplements, life stages like pregnancy may require fortified foods and dietary supplement intake.
That said, it’s important to note that vitamin B12 supplementation is not part of the WHO recommendations for supplements required during pregnancy, so speak to a healthcare professional before buying and taking B12 supplements.
You may also like: Best Supplements for Breastfeeding Mothers.
Gastrointestinal disorders and gastrointestinal surgery patients
Stomach and small intestine disorders can also lead to vitamin B12 deficiency. In particular, individuals with celiac disease and Crohn’s disease are at risk.
In a study to evaluate micronutrient deficiencies in subjects with celiac disease), the researchers found that 5.3% of the cohort had low serum levels of vitamin B12, compared to only 0.3% of the population without celiac disease.
In a similar vein, individuals who have had surgery to remove sections of their gastrointestinal system may suffer impaired vitamin B12 absorption and, consequently, vitamin B12 deficiency.
This is because such surgeries may remove or reduce cells that produce hydrochloric acid and “intrinsic factor”, both necessary for how the body absorbs vitamin B12 from food.
Research suggests that a dose of 1,000 mcg daily of oral methylcobalamin is effective in helping patients who have undergone gastrointestinal surgery to reverse their vitamin B12 levels back to normal.
Individuals with pernicious anemia
Pernicious anemia is a condition where the body’s antibodies destroy the cells that line the stomach. The continuous destruction of these cells limits the stomach’s capacity for secreting the acid and enzymes needed to absorb food-bound vitamin B12.
Additionally, these rogue antibodies bind to “intrinsic factor,” an important, further limiting the body’s ability to absorb cobalamin. Primarily, pernicious anemia requires intramuscular injections of vitamin B12 to circumvent the dependence on intestinal absorption. However, large doses of oral supplementation also work.
A dose of 1,000 mcg of cobalamin should provide the daily required dietary allowance of vitamin B12.
This is because B12 supplements are not bound to protein, thus minimizing the effect pernicious anemia has on their absorption. Moreover, some intrinsic factors are still left in the stomach to facilitate absorption.
It is also worth mentioning that one in five (about 20%) relatives of individuals suffering from pernicious anemia also have the condition. So, it’s something to take note of.
Why Not Natural offers high-quality Vitamin B12 supplements, ensuring you get the best value for your health.
How much vitamin B12 do I need daily?
The average healthy adult requires 2.4 mcg of vitamin B12 daily. However, people with certain conditions and different life stages may need more.
The Food and Nutrition Board has specified a recommended dietary allowance (RDA) for healthy individuals. The RDA is the “Average daily level of intake sufficient to meet the nutrient requirements of nearly all (97%–98%) healthy individuals.”
The RDA per age group is as follows:
- Newborn to six 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 years and above: 2.4 mcg
- Pregnant women: 2.6 mcg
- Lactating mothers: 2.8 mcg
These figures apply to both males and females. Per the recommendations, older adults must add vitamin B12-fortified food or a supplement to their daily consumption to maintain a healthy vitamin level.
In a study examining 100 adults, the researchers found that supplementing with 500 mcg of vitamin B12 increased serum levels in 90% of the subjects.
Dose for individuals with certain conditions
Certain conditions alter a person’s daily vitamin B12 needs. For example, individuals with pernicious anemia cannot absorb the needed quantity from food and thus require supplementation.
Based on a comprehensive meta-analysis of previous studies, researchers concluded that an oral dose of 1000 mcg of vitamin B12 daily was sufficient to replace lifelong intramuscular treatments in individuals with pernicious anemia.
Adults already dealing with a vitamin B12 deficiency also have a different recommended daily dose. The dose and treatment routine will depend on how severe the deficiency is and the root cause.
People with diet-related deficiencies may only require one-time injections and subsequent oral supplementation. In contrast, others may require long-term injections, except the root cause can be corrected.
How do I take vitamin B12 supplements?
You can take vitamin B12 in three primary ways: orally, like most drugs, sublingually like a lozenge (usually under the tongue), and through intramuscular injection. There’s also the less popular option, intranasal.
In terms of efficacy, there are some slightly conflicting reports. Some studies suggest that sublingual delivery is more efficient, while others maintain that the efficacy is similar across the board.
In a retrospective study of 4,281 patients who received vitamin B12 supplementation, 19.3% of the cohort received intramuscular injections, while 80.7% received sublingual tablets.
The researchers found that the “mean difference between serum vitamin B12 levels before and after administration of VB12 supplements was significantly higher in the sublingual group vs. the intramuscular injection group.”
That said, many reports advocate for using the sublingual supplement form of delivery owing to its many advantages. These advantages include relatively lower cost and tolerance, and it is better suited for individuals requiring prolonged vitamin B12 supplementation.
While you may opt for B-complex vitamins, they may not contain adequate doses of vitamin B12 necessary to help alter your blood levels.
What are the benefits of vitamin B12 supplements?
Some of the health benefits of vitamin B12 include:
1. Aids in the production of white and red blood cells and platelets
Vitamin B12 is essential in the body's production of healthy red blood cells (erythrocytes) that carry oxygen to every nook and cranny.
Healthy red blood cells are small and round in shape. Poor vitamin B12 levels not only affect the production of red blood cells but also lead to overgrown and weirdly shaped cells known as megaloblasts.
At this larger size and irregular shape, more red blood cells find it harder to leave the production hub, your bone marrow, to the bloodstream.
Even when the megaloblasts manage to escape into the bloodstream, they cannot carry enough oxygen due to their impairment.
As such, your body has a less-than-optimal number of oxygen-rich red blood cells.
Scientists describe this condition as vitamin B12–deficiency anemia, and some of the symptoms include fatigue, lethargy, and low energy levels.
You may also like: 5 Top Vitamins for an Energy Boost: Essential Nutrients for Boosting Your Energy Levels.
2. Helps prevent cardiovascular diseases
Research studies have established a strong link between elevated homocysteine and the risk of developing cardiovascular disease. Cobalamin, vitamin B6 or folic acid deficiency are the leading cause of high homocysteine levels.
Interventional studies have demonstrated the effect of daily vitamin B12 and folic acid supplementation on reducing homocysteine levels. A meta-analysis research report concluded that taking a daily dose of “0.5-5 mg folic acid and about 0.5 mg vitamin B12” can reduce homocysteine by 25% to 33%.
Another study reached a similar conclusion. According to the authors, a supplementation policy containing cobalamin and folic acid is “likely more effective” at decreasing blood homocysteine levels and, consequently, the risk of cardiovascular diseases.
3. Helps prevent early pregnancy loss and underweight newborn
Researchers have observed a robust linear association between vitamin B12 deficiency and the risk of the newborn being underweight. Vitamin B12 levels during pregnancy also influence whether the mother delivers preterm.
Low vitamin B12 levels may also increase the risk of early pregnancy loss, especially when combined with high levels of homocysteine.
One study examined 83 women who experienced early pregnancy loss and 70 healthy pregnant women in their first three months to determine the role folic acid, vitamin B12, and homocysteine levels play in pregnancy-related complications.
The results showed that folic acid is not correlated with the risk of early pregnancy loss. However, poor vitamin B12 levels and elevated levels of homocysteine “were individually found to be significant risk factors for early pregnancy loss.”
A combination of both risk factors provided a heightened risk of experiencing early pregnancy loss.
4. May indirectly help reduce the risk of breast cancer
Researchers in Mexico examined the relationship between the risk of breast cancer and folate, vitamin B6, and vitamin B12 intake. The researchers recruited 475 women previously diagnosed with breast cancer and 1,391 women with no history of the disease.
A review of each group’s diet via a food frequency questionnaire revealed that postmenopausal women getting a high intake of folate and vitamin B12 were less likely to develop breast cancer, with a stronger inverse correlation observed amongst those whose diet was very high in cobalamin.
Our B12 + Folate combo contains 2,000 mcg of the former and 800 mcg of the latter. It’s the perfect supplement for postmenopausal women.
5. Decreases the risk of neural tube defects (NTD)
Doctors observe neural tube defects (NTD) in about 300,000 babies every year. A spinal cord or brain defect characterizes NTD.
A review of existing literature on the subject shows that mothers whose parents had NTD had decreased vitamin B12 levels. Moreover, the active form of vitamin B12, Holo-transcobalamin, was also low in the group.
Another popular key finding from most studies is that elevated homocysteine levels are a significant risk factor. We established earlier that cobalamin, vitamin B6, or folic acid deficiency were the leading causes of elevated homocysteine levels.
As authors in another clinical study wrote, there are “significantly higher homocysteine levels in women carrying affected fetuses than in control women.”
Sadly, NTD occurs between the 21st and 28th days post-conception, when most women are unaware of their condition. This highlights the need for women of reproductive age to eat well and consume a diet high in vitamin B12 and folic acid.
6. Reduces the risk of osteoporotic fractures
Vitamin B12 deficiency causes pernicious anemia, which has been strongly linked to an increased risk of osteoporosis, low bone mineral density, and fractures.
One study followed 131 individuals who had previously been diagnosed with pernicious anemia for multiple years. The researchers found that the rate of fracture in the pernicious anemia group was considerably higher than in the control group.
The pernicious anemia group members were 2.9 times and 1.9 times more likely to suffer distal forearm fractures and proximal femur fractures, respectively.
Fortunately, vitamin B12 supplementation can improve bone density and reduce the risk of osteoporotic fractures. A study investigating such reversal found that vitamin B12 supplementation increased bone density by 79% in the femoral neck region and 17% in the lumbar area.
Furthermore, the researchers found that the subjects experienced no further vertebral fractures during the two years since the cobalamin treatment was initiated.
7. Helps preserve DNA integrity
The body needs methionine synthase for DNA synthesis and repair. However, to function effectively, methionine synthase also requires methylcobalamin, an active form of vitamin B12.
Vitamin B12 “ensures structural stability of important regions of the chromosomes such as the centromeres and the subtelomeric DNA.”
8. May help prevent age-related blindness
Age-related macular degeneration (AMD) is a serious condition that can lead to blindness and low vision.
A study of 2,335 participants found that low vitamin B12 levels and increased homocysteine were independently correlated with a high risk of developing AMD.
Furthermore, the results of this study were adjusted for other factors like smoking, age, and gender.
In another study, researchers also examined 60 participants diagnosed with AMD.
Consequent tests showed significantly lower plasma vitamin B12 levels in half of the patients, emphasizing how maintaining a healthy serum vitamin B12 level might help retain vision, even in old age.
9. May aid recovery from depression
Researchers found that higher vitamin B12 levels may give patients a better chance of recovery from major depression.
A meta-analysis of several studies concluded that early vitamin B12 supplementation may “delay the onset of depression and improve the effect of antidepressants when used in conjunction with Vitamin B12.”
Researchers in a study split a group of 73 depressed patients with low vitamin B12 levels into two. The first group received vitamin B12 supplementation and antidepressants, while the control group received only antidepressants.
After three months, each member in the vitamin B12 group showed at least 20% in their HAM-D, a depression scale, scores. Only 69% of the control group experienced a lower HAM-D score.
10. Helps with cognition in children
Different studies have shown an adverse relationship between vitamin B12 levels and impaired cognitive development in children. Vitamin B12 is vital in many processes crucial for optimal cognitive development.
These processes include neural myelination, synaptogenesis, myelination, and neurotransmitter synthesis.
While all these may be foreign concepts to you, the bottom line is that vitamin B12 is vital in ensuring children have well-developed brains.
For more comprehensive details on the benefits of vitamin B12, please read: Vitamin B12: The Ultimate Guide to Understanding its Importance and Sources.
What are the deficiencies of vitamin B12?
Some of the symptoms or after-effects of vitamin B12 deficiencies include megaloblastic anemia, tongue glossitis or soreness, newborn neural tube defects in women, elevated levels of homocysteine, constipation, appetite loss, numbness and tingling of the hands, memory loss, weight loss, and infertility.
We’ve discussed the significant deficiencies of vitamin B12 throughout this article, so we won’t bother you with the details again. However, it’s essential to know that it takes a long time for vitamin B12 deficiency to become apparent.
That’s because the body stores a whopping 2,500 mcg of vitamin B12 in the liver. Despite inadequate vitamin B12 intake, it takes, on average, three to five years to deplete.
The lesson is to remain proactive in maintaining a healthy intake of vitamin B12, whether from food sources or supplements.
What foods are rich sources of vitamin B12?
Clams, mussels, mackerel, crab, nutritional yeast, beef, salmon, rockfish, and milk are some of the best sources of vitamin B12. For a better perspective, three ounces of clams provide 84.1 mcg of vitamin B12, about 35 times the daily RDA.
Other notable sources of vitamin B12 include turkey, oysters, cheese, fortified breakfast cereals, eggs, and yogurt.
Takeaway: Make informed choices for better health with vitamin B12 supplementation
When choosing a Vitamin B12 supplement, consider factors like dosage, formulation, and quality. Opt for methylcobalamin for better absorption and effectiveness.
With benefits ranging from increased energy to improved cognitive function, incorporating Vitamin B12 into your supplement routine can make a significant difference.
Don't let confusion in the supplement aisle hold you back—choose Why Not Natural for your B12 needs and experience the vitality you deserve. Why Not Natural's Vitamin B12 supplements are safe, clean, and concentrated to get a quick jump on your base levels.
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