The main difference between cyanocobalamin and methylcobalamin is that cyanocobalamin is a man-made form of B12 found only in pills, while methylcobalamin is a natural form your body can use right away. Cyanocobalamin needs to be changed by your body before it works. Methylcobalamin is ready to use the moment you take it.
Both types help fix B12 problems. But they work in different ways. In this guide, you’ll learn how each one is made, how well your body takes them in, and which one might work best for you. We’ll also talk about who should take each type and answer the most common questions people ask.
What Is Cyanocobalamin?
How It’s Made
Cyanocobalamin is a man-made type of vitamin B12. It’s not found in nature. Scientists create it in labs. It gets its name because it has a tiny piece of cyanide in it.
Don’t worry about the cyanide part. The amount is very, very small. It’s so tiny that it won’t hurt you. Your body gets rid of it through your pee.
How Your Body Uses It
When you take cyanocobalamin, your body has to do some work first. Your body must change it into methylcobalamin or adenosylcobalamin before it can use it. Think of it like getting a toy that needs batteries. You can’t play with it right away. You need to add batteries first.
This change happens in your liver. Your liver takes off the cyanide part and puts on a different part. Only then can your cells use it.
Where You Find It
You’ll find cyanocobalamin in most cheap vitamins. It’s also in foods that have B12 added to them, like some cereals. Companies use it because it lasts a long time on the shelf and costs less to make.
What Is Methylcobalamin?
The Natural Form
Methylcobalamin is a natural form of B12. Your body makes it. It’s also found in foods like fish, meat, eggs, and milk. This is the form your cells actually use to do important jobs.
No Changes Needed
The big plus with methylcobalamin? Your body can use it right away. It doesn’t need to be changed. It’s already in the active form. It’s like getting a toy with batteries already inside. You can play with it the moment you open the box.
Where It Comes From
In nature, methylcobalamin is in animal foods. Fish, beef, chicken, eggs, and dairy all have it. When you eat these foods, you get methylcobalamin. You can also buy it as a pill or liquid.
How Well Does Your Body Absorb Each Type?
Absorption Rates
Here’s something that might surprise you. Some studies show that your body absorbs cyanocobalamin a little better than methylcobalamin. One study found people absorbed about 49% of cyanocobalamin compared to 44% of methylcobalamin.
But that’s not the whole story.
How Long It Stays In Your Body
Other research shows that methylcobalamin stays in your body longer. Studies found that three times as much cyanocobalamin was passed out in pee. This means methylcobalamin sticks around longer to do its job.
Recent 2024 research shows that at low doses (around 2.5 micrograms), the body absorbs about 50% of B12. At higher doses, this drops to about 15%. This is true for both types.
The Big Picture
Many experts say the differences in how well they’re absorbed are very small. Factors like your age and your genes matter more than which type you take.
Key Differences Between The Two Forms
| Feature | Cyanocobalamin | Methylcobalamin |
| Origin | Man-made in labs | Found in nature and foods |
| Ready to Use | No, needs to be changed first | Yes, ready right away |
| Cost | Cheaper | More expensive |
| Shelf Life | Lasts a long time | Breaks down faster |
| Absorption | Slightly better absorbed | May stay in body longer |
| Cyanide | Has tiny bit of cyanide | No cyanide |
Which Form Works Better For Health?
Both Fix B12 Problems
The good news? Both types can fix B12 problems. Studies show both forms raised B12 levels in people who didn’t have enough.
In one study, seven people with low B12 took methylcobalamin pills. After two months, their B12 levels were normal. Another study showed cyanocobalamin pills worked too. Ten people with a B12 problem took them for three months. Their levels got better.
Energy and Fatigue
Both forms help with feeling tired. When your B12 is low, you feel worn out. Taking either type can boost your energy. Some people say they feel more alert within days of starting B12.
If you want fast results, methylcobalamin might be better. Since it’s ready to use, some people feel a difference sooner.
Nerve Health
Research shows both forms help with nerve problems from diabetes. A review of seven studies found both methylcobalamin and cyanocobalamin reduced nerve pain and tingling.
But some doctors prefer methylcobalamin for nerve issues. It’s the specific form your nervous system needs. Studies show it helped people see better by improving how fast their eyes could focus. Cyanocobalamin didn’t show the same results.
Brain Function
Your brain needs B12 to work well. Both forms support brain health. They help make chemicals your brain uses to think and remember.
Methylcobalamin has an extra job here. It helps with methylation, a process that affects how your brain makes important chemicals and cleans out toxins.
Learn more about how methylated B12 helps with cognitive function.
Who Should Take Which Type?
Cyanocobalamin Works Well For
- People who just want to prevent low B12
- Those on a tight budget
- Anyone who needs a stable supplement that lasts
- People with healthy livers that can do the conversion
Methylcobalamin Is Better For
- People with MTHFR gene changes. These folks have trouble changing cyanocobalamin into the active form.
- Anyone with liver problems
- People who want faster results
- Those with nerve pain or brain fog
- Vegans and vegetarians who need reliable B12
If you’re not sure which you need, learn about MTHFR and methylated B12.
The MTHFR Connection
What Is MTHFR?
MTHFR is a gene everyone has. But about 30-40% of people have a change in this gene. This change is called a mutation.
When you have this mutation, your body has a harder time changing vitamins into forms it can use. This includes changing cyanocobalamin into methylcobalamin.
Why It Matters
People with MTHFR mutations struggle to use man-made B12. The change process in their body doesn’t work well. This means they might not get the full benefit from cyanocobalamin.
If you have MTHFR mutations, you may need up to 70% more effort to change B12 into the form your body needs. That’s a lot of extra work your body has to do.
The Solution
For people with MTHFR, methylcobalamin is the better choice. It doesn’t need to be changed. Your body can use it right away.
Many doctors test for MTHFR if you have:
- Constant tiredness
- Brain fog
- Nerve tingling
- High homocysteine levels
Check out more about symptoms of B12 deficiency.
Safety and Side Effects
Is Cyanocobalamin Safe?
Many people worry about the cyanide in cyanocobalamin. Here’s what you need to know.
The amount of cyanide is very small. It’s too tiny to cause harm, even if you take it for years. Your body easily gets rid of it.
That said, some research shows that even small amounts of cyanide can cause headaches, dizziness, or stomach upset in some people.
If you have kidney problems or smoke, you might want to avoid cyanocobalamin. These conditions make it harder for your body to clear out cyanide.
Is Methylcobalamin Safe?
Methylcobalamin is very safe. Most side effects are mild and go away fast. Serious reactions are rare.
Some people might have:
- Mild stomach upset
- Headache
- Skin rash (very rare)
If you have trouble breathing, chest tightness, or bad swelling, get help right away. These are signs of an allergic reaction.
Both forms are safe for most people. B12 is a water-soluble vitamin. Your body passes out what it doesn’t need.
Discover more about side effects of methylated B12.
Best Ways To Take Each Form
Pills and Tablets
Both types come in pills you swallow. This is the most common way to take them.
But here’s a problem: Only about 1-4% of B12 gets absorbed through your gut. That’s not very much.
Under the Tongue
A better way is to put B12 under your tongue. This is called sublingual. When you hold it under your tongue or between your gum and cheek, it goes straight into your blood. It doesn’t have to go through your stomach first.
This works great for both types. But it’s especially helpful if you have stomach problems or trouble absorbing nutrients.
Shots
B12 shots go right into your muscle. They skip your stomach completely. Doctors often use cyanocobalamin or hydroxocobalamin for shots.
Shots work fast. They’re good for people with very low B12 or serious absorption problems.
Sprays
Some B12 comes in nose sprays. These are handy and easy to use. They work like the under-the-tongue method.
Learn about how to take methylated B12 for best results.
Food Sources vs. Supplements
Where B12 Comes From Naturally
B12 is made by tiny bugs called bacteria. Animals eat these bacteria in their food. The B12 ends up in their meat and milk.
Natural food sources include:
- Beef liver (the richest source)
- Clams and oysters
- Salmon and tuna
- Chicken and turkey
- Eggs
- Milk, cheese, and yogurt
All of these contain methylcobalamin, the natural active form.
Find out more about foods rich in methylated B12.
Who Needs Supplements?
You might need B12 pills if you:
- Don’t eat meat or dairy (vegans and vegetarians)
- Are over 50 (stomach acid decreases with age)
- Take certain medicines (like metformin for diabetes)
- Have stomach or gut problems
- Had weight loss surgery
A 2024 study on vegans found that cyanocobalamin worked better than methylcobalamin at keeping B12 levels up. People taking cyanocobalamin had higher active B12 in their blood.
But remember, the study also found that taking B12 more often (not just the amount) mattered a lot. People who took it more times per week did better.
Read about why vegans need methylated B12.
How Much Do You Need?
Daily Needs
Most adults need about 2.4 micrograms of B12 each day. Pregnant women need 2.6 micrograms. Breastfeeding moms need 2.8 micrograms.
Supplement Doses
Most B12 pills have way more than the daily need. You’ll see doses from 500 to 5,000 micrograms.
Why so much? Because your body only absorbs a small part of what you take. At higher doses, the absorption percentage drops, but you still get enough total B12.
For example:
- A 2.5 microgram dose: Your body absorbs about 50% (1.25 micrograms)
- A 10 microgram dose: Your body absorbs about 15% (1.5 micrograms)
Both end up giving you about the same amount.
Can You Take Too Much?
B12 is very safe. You can take high doses without major problems. But very high amounts might cause nausea, stomach cramps, or diarrhea in some people.
Your body is smart. It only takes in what it needs. The rest passes out in your pee.
Check our dosage guide for methylated B12.
Cost Comparison
Why Cyanocobalamin Costs Less
Cyanocobalamin is cheaper to make and lasts longer on the shelf. This makes it the go-to choice for most vitamins and fortified foods.
A bottle of cyanocobalamin might cost $8 to $15.
Why Methylcobalamin Costs More
Methylcobalamin costs more to produce. It’s less stable and can break down more easily. It needs special storage.
A bottle of methylcobalamin might cost $15 to $30 or more.
Is the extra cost worth it? That depends on your needs. If you have MTHFR or want the active form, yes. If you just want to prevent low B12 and have a healthy liver, cyanocobalamin works fine.
Testing Your B12 Levels
Regular B12 Blood Test
Most doctors test total B12 in your blood. This test has limits. Some people have good B12 in their blood but their cells can’t use it. The number looks normal, but you still have symptoms.
Better Tests
A test for active B12 (called holotranscobalamin) gives a clearer picture. It shows how much B12 your body is actually using.
Another good test is MMA (methylmalonic acid). High MMA means your cells don’t have enough working B12.
Testing for MTHFR
If you think you might have MTHFR changes, ask for a genetic test. This usually involves a blood draw or cheek swab.
Knowing your MTHFR status helps you pick the right B12 type.
Common Questions About The Two Forms
Can You Switch Between Them?
Yes. You can switch from cyanocobalamin to methylcobalamin or vice versa. Some people try both to see which one makes them feel better.
Does One Work Faster?
Some people notice more energy within days with methylcobalamin because it’s ready to use. But both types show their main benefits after 3 to 6 weeks of steady use.
Can You Take Both Together?
Yes. There’s no harm in taking both types. Your body will use what it needs.
Which One Is Better for Seniors?
Older people often have lower stomach acid, which makes it harder to absorb B12 from food. Methylcobalamin might be a better choice because it bypasses some of these absorption problems.
Learn more about why methylated B12 is recommended for seniors.
Do They Interact With Medicines?
Both forms can interact with some drugs. These include antibiotics, diabetes medicines, and drugs that lower stomach acid. Always talk to your doctor if you take prescription medicines.
Real Research: What Science Says
Recent Studies
A 2024 study looked at vegans taking either cyanocobalamin or methylcobalamin. The cyanocobalamin group had better results in keeping active B12 levels up.
But another angle matters too. Research shows methylcobalamin is better at staying in your body. It’s not flushed out as quickly as cyanocobalamin.
What Experts Recommend
Most recent research says the differences are small for healthy people. Both forms work to fix B12 problems.
However, a review in Integrative Medicine found that methylcobalamin was more effective at keeping B12 stores filled in the body.
Many functional medicine doctors lean toward methylcobalamin, especially for people with:
- MTHFR mutations
- Chronic fatigue
- Nerve problems
- Brain fog
Traditional doctors often stick with cyanocobalamin because it’s been studied longer and costs less.
Making Your Choice
Questions To Ask Yourself
Do you have MTHFR mutations?
If yes, methylcobalamin is likely better for you.
Do you have liver or kidney problems?
Methylcobalamin might be safer since it doesn’t need liver processing.
Are you on a budget?
Cyanocobalamin is cheaper and still works well for most people.
Do you have nerve pain or brain fog?
Methylcobalamin might give you better results faster.
Do you eat animal foods?
If not, you need B12 supplements. Either type can work, but consistency matters more than which form.
Talk To Your Doctor
Before starting any new supplement, talk to your doctor. They can:
- Test your B12 levels
- Check for MTHFR mutations
- Review your medicines
- Suggest the right dose
- Monitor your progress
Try And See
Sometimes the best way to know what works is to try it. Some people feel better on methylcobalamin. Others do fine with cyanocobalamin.
Give it at least 4-6 weeks. That’s how long it takes to see real changes in your B12 levels and symptoms.
Final Thoughts
Both cyanocobalamin and methylcobalamin can fix B12 problems and keep you healthy. The main difference? Cyanocobalamin is man-made and needs to be changed by your body. Methylcobalamin is natural and ready to use right away.
For most healthy people, either one works fine. But if you have MTHFR gene changes, liver issues, or want faster results, methylcobalamin is the better pick. It’s the form your body actually uses, so it skips the extra steps.
Recent studies show the absorption differences are small. What matters most is taking B12 consistently and at the right dose for your needs.
Ready to try high-quality methylated B12? Shop our methylated B12 supplements and feel the difference of the active, ready-to-use form your body loves.
Remember: B12 is vital for energy, nerves, brain function, and making red blood cells. Whether you choose cyanocobalamin or methylcobalamin, the important thing is to keep your levels up. Your body will thank you.