Whether you realize it or not, B12 is a critical vitamin involved in very important processes in your body like energy production and metabolism.
It's currently estimated that as many as 50% of people in the US have B12 deficiency or suboptimal B12 (1) levels in their body.
This means that as many as 1 out of 2 people are walking around with sub-optimal energy levels and a slower than normal metabolism.
It's no wonder that many patients who use B12 shots experience many benefits that range from increased energy to weight loss and even better sleeping patterns.
In this post I am going to walk you through just some of the benefits that you might experience while using vitamin B12 shots:
#1. Increases your energy levels & fights fatigue
One of the most common symptoms of B12 deficiency is increased fatigue or lack of energy levels.
What's interesting is that we know why this happens:
Vitamin B12 (along with other B vitamins) is required for proper energy production in your mitochondria.
Recall from basic biology that your mitochondria produce "energy" for your body in the form of a molecule called ATP (adenosine triphosphate).
The number of mitochondria in your cells and muscles and how effective they are working determine your subjective sense of "energy".
Anything that lowers energy production in the mitochondria may manifest as fatigue.
Vitamin B12 plays an important role in this process as you can see below:
In addition, it has been shown in studies that supplementing with B12 can increase energy levels (2).
This is why vitamin B12 is put into "energy drinks" and other supplements that are meant to boost vitamin B12.
But here's the most important part:
One of the main reasons for Vitamin B12 deficiency is due to malabsorption of vitamin B12 in our GI tract.
So basically you can be consuming B12 in your diet (or even taking supplements with B12) but not actually absorbing it (3).
This is why one of the main benefits of taking B12 shots is increased energy levels.
By taking a shot you are bypassing the GI tract and allowing for 100% absorption into the body straight into the cells (which is where B12 has its action).
If you are taking Vitamin B12 supplements and not feeling any different than it may be due to a lack of absorption.
#2. Improves your metabolism
Another very important benefit of vitamin B12 supplementation is an increase in basal metabolic rate or metabolism.
Your metabolism is the most important factor when it comes to determining your weight.
Your metabolism represents the number of calories that you burn while at rest and represents around 90-95% of all calories that you burn in any given day.
The problem here is that most of you are walking around with a slower than normal metabolism due to a variety of factors.
Low vitamin B12, low mitochondrial energy production, low thyroid hormone, a history of recurrent dieting, etc. have all been shown to slow down your metabolism.
So instead of burning, let's say, 2,000 calories per day - you may only be burning 1400-1500 calories per day if your metabolism is only functioning at 75% of normal.
Obviously with a metabolism that slow it will be VERY difficult to lose any weight.
Vitamin B12 is one of those nutrients that can affect your metabolism and here's how:
We've already established the importance of normal mitochondrial energy production in the first section, but what you probably didn't realize is that your mitochondria also help set your basal metabolic rate (4).
The amount of energy that you produce in your mitochondria helps set your metabolism for your entire body.
More energy production = more energy available for use = higher energy burn = more heat production and more calories burned overall
So if you have suboptimal Vitamin B12 levels or high levels of fatigue your metabolism may be slower than normal.
If this reduction in metabolism is due to low levels of B12 then B12 shots can improve your metabolism.
#3. Helps with weight loss
B12 shots don't directly result in weight loss but they do in an indirect way.
Let me explain:
Some of the benefits (including those we've already discussed) of B12 shots include:
- Better sleep
- Higher metabolism
- More energy
- Increased mood
What's interesting is that all of these "lifestyle" factors influence how and if your body will lose weight and burn fat mass.
Lack of sleep has been shown to increase your risk of developing obesity (5) by increasing your blood sugar.
Likewise, a slow metabolism can help predict weight gain long term (6) (especially after weight loss).
Low energy levels make exercise difficult and it has been shown to increase your risk of weight gain (7).
Low B12 is also associated with depression (8) which is directly associated with weight gain and obesity.
All of these are intuitive and shouldn't come as a shock to you, so it also shouldn't come as a surprise to know that if you can improve these factors then you can help your body with weight loss.
Vitamin B12 shots can help improve your sleep, increase your energy, normalize your metabolism and improve your mood.
ALL of these factors may indirectly influence your ability to lose weight and may explain why patients who use vitamin B12 shots usually report some degree of weight loss.
Vitamin B12 shots can also be combined with lipotropic supplements to further help boost weight loss.
Lipotropic vitamins and nutrients directly help your body burn fat and break down adipose tissue which results in fat loss.
But this effect is different from how vitamin B12 itself is working to help with weight loss in your body.
The lipotropic that can be combined with B12 shots include Methionine, Inositol, and Choline.
#4. Helps improve sleeping patterns & circadian rhythm
Another VERY important, and often under-appreciated benefit of methylcobalamin is how it affects your circadian rhythm.
Your circadian rhythm is the process that helps regulate the quality and depth of your sleep (among other factors) which can directly influence your mood, energy levels, and weight.
Studies have shown that methylcobalamin (NOT cyanocobalamin) can improve this rhythm (9).
It should be noted that this study compared the effects of cyanocobalamin to methylcobalamin and found that methylcobalamin is the only form of vitamin B12 to have this effect.
Both cyanocobalamin and methylcobalamin are forms of Vitamin B12 but they are not created equal.
Cyanocobalamin is considered the cheaper and less effective form of B12.
Compared to methylcobalamin which comes premethylated and ready for processing in your body and mitochondria.
If you get B12 shots, make sure that you are getting methylated B12 for best results.
If you are having sleep issues including difficulty falling asleep, difficulty staying asleep, problems getting tired at night or low energy levels then you may be experiencing problems with your circadian rhythm.
Taking methylcobalamin B12 shots may improve this rhythm and help increase your energy and (as discussed above) help with weight loss.
#5. Increases concentration & mood
Is your mood down? or are you feeling more "depressed" than usual?
You aren't alone.
We have record numbers of patients taking anti-depressants for "depression" in hospitals and in the community.
Depression by itself isn't a diagnosis but a sign of something else going on in your body.
This may include nutrient deficiencies, high levels of inflammation, lack of exercise, weight gain, etc.
No matter how you look at it there are at least 50+ known causes of depression out there.
One of the main, and most well known, is low levels of Vitamin B12.
It has been shown that vitamin B12 can help increase your mood and fight off depression.
What's great is that B12 can be used in conjunction with other therapies for B12 and can augment your results (10) to help increase your mood quickly.
Likewise, B12 has also been shown to increase concentration (11) which may reduce symptoms such as the inability to focus on projects and tasks.
#6. Boosts your immune system
Vitamin B12 also plays a critical role in your immune system.
Supplementing with methylcobalamin (not cyanocobalamin) has been shown to restore abnormalities in the CD4/CD8 T cell ratio (12).
These factors are very important for fighting off viruses and bacteria that come into contact with your body.
Changes in this ratio increase your risk for developing certain infections and may reduce the ability of your body to effectively get rid of these infections.
This may result in patients who get sick frequently or who stay sick longer than normal.
The exact mechanism of how B12 interacts with the immune system isn't well understood but it has been shown that low levels impact the body's ability to fight off various infections.
If you have issues with immunity then it would be worth evaluating your B12 levels to see if they might be contributing.
#7. May increase hair growth or stop hair loss
It turns out that there are several nutrients that required for optimal hair growth and Vitamin B12 happens to be one of them.
If you are having issues with hair loss or your hair is thinning then read on...
In order for proper hair growth to continue and be optimal, you need high enough levels of serum Vitamin B12, ferritin and hemoglobin (13).
Deficiencies in any one of these nutrients may result in a reduction in hair growth or even hair loss.
While it is true that many factors (including hormones) influence your hair growth/hair loss, it is worth noting that vitamin B12 plays a special role.
I would never recommend that you take only B12 if your hair is falling out, but taking B12 with other supplements to boost hair loss is a great idea and can be very beneficial.
You can read more about various factors causing hair loss in this post.
Where to get B12 shots & How to use them
Not all forms of B12 are created equal.
If you want to use B12 shots you need to make sure you are getting high quality, pharmaceutical grade B12 in its methylated form: methylcobalamin.
You will also need to make sure you get a high enough dosage and make sure the dose isn't watered down or lower than normal.
That generally means at least 5,000mcg of methylcobalamin taken once per week.
Some places will dilute the concentration or use cyanocobalamin because they are cheaper, so make sure you get high-quality ingredients.
Are B12 shots safe?
Yes, taking Vitamin B12 is very safe.
There is a small risk of developing redness at the injection site but it can be minimized by using proper techniques and making sure to use an antiseptic prior to application.
Vitamin B12 is a water soluble vitamin which means that high levels in the blood will be urinated out.
There is no real risk of developing Vitamin B12 toxicity unless you have chronic and severe kidney function (meaning your urination isn't normal).
Outside of these issues vitamin B12 shots are very well tolerated.
How often should you use a B12 shot?
Most patients will need 1 shot every 7 days.
In some cases, supraphysiologic dosages may be necessary.
That means some patients may need an injection every 5 days instead of every 7 days.
Personally, I use 2 shots per week (though not every week) but that is due to the fact that I have methylation issues.
Most patients are fine using 1 shot every 7 days.
If you feel you need more you should discuss that with your Doctor.
Recap + Final thoughts
Taking B12 shots may result in a dramatic improvement in your symptoms and can help in a variety of ways.
The most common benefits of taking B12 shots include:
- Increased energy
- More weight loss
- Better mood and increased concentration
- Better sleep
- Hair growth
- Better metabolism
These are not the only benefits of B12 shots, but just some of the more common.
It's also important to realize that B12 shots provide more benefit than taking oral supplements alone.
This has to do with various issues regarding the absorption of B12 in the gastrointestinal tract.
Taking B12 shots allows for 100% absorption directly into the tissues.
Now it's your turn:
Are you taking B12 shots?
Have they helped increase your energy?
Have they helped with weight loss?
Leave your comment below!
References (Click to Expand)
This post was most recently updated on February 15th, 2019