Is This Health Injection the Secret to Effective Weight Loss?

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It’s no secret that we’re savvier than ever when it comes to taking supplements. A study found that nearly half of us are now popping health-boosting pills in a bid to improve nutrition levels. But, as with everything in the wellness world, vitamins are fast advancing, and B12 shots are just one of the ways you can take your healthy lifestyle to the next level. The likes of Hailey Bieber and Lea Michele are already fans of the procedure, and both have shared Instagram snaps of themselves taking a literal shot to the butt.

What Is a B12 Shot?

A B12 shot is recommended for those who have a B12 deficiency or pernicious anemia. Vitamin B12 is naturally found in foods such as fish, meat, and eggs. However, the shot contains a human-made form of B12 called Cyanocobalamin.

“I’m a big fan of B12 shots,” Michele wrote during a trip to Nurse Jamie’s office before listing off a whole heap of wellness benefits, including weight loss and a bolstered immune system. But is this really the savior celebs proclaim or a total fad?

Keep scrolling to discover whether getting B12 injections is for you.

Who Should Try It?

Those with a vitamin B12 deficiency will see the most significant benefits of getting a shot, so look out for common symptoms like fatigue, irritability, and nausea.

"Many people are deficient in B12, especially those who eat very little meat or dairy," says Arielle Levitan, MD. "B12 shots are a good way to deliver B12 to those who are B12 deficient but who can not absorb B12 through the oral route."

Meet the Expert

  • Arielle Levitan, MD, is a board-certified internal medicine physician who practices in Chicago. She has a special interest in women’s health and preventive medicine and is the founder of Vous Vitamin
  •  Nicole Avena, PhD, is a nutrition and health expert and the Assistant Professor at Mount Sinai Medical School. She is also the visiting professor of Health Psychology at Princeton University.

As Levitan indicated, vegans and vegetarians may discover they are deficient as B12 is found in meat. Those who smoke, take certain prescription medicine, or have a gastrointestinal disorder are also at great risk of lacking in this vitamin. If you’re dealing with the latter, injections are usually recommended over oral supplements, as they bypass the stomach and are directly absorbed into the bloodstream.

Let us give you a word of warning: Many fall into the trap of thinking more B12 equals more energy for everyone, and that simply isn’t going to be the case. The vitamin is water-soluble, so when you take it in excess, your body will eliminate what it doesn’t need. If your B12 levels are fine as is, instead of multiplying your energy, you’ll be wasting money on a treatment that’s only effective if you have a deficiency, so check with your doctor first.

The Benefits of B12 Shots

If your doctor has indicated you are deficient in B12, there are many benefits of taking the shots, so your body has enough of the vitamin to be in optimal health.

B12 Keeps Your Brain Sharp 

Because of the way B12 supports healthy blood cells, nerve cells, and proteins, if you lack this vitamin, then it will show up as the dreaded brain fog:

"B12 deficiency can manifest as fatigue, lack of focus, and memory trouble," explains Levitan.

It Keeps Your Energy High

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If you are deficient in B12, a shot can help keep your energy levels functioning where they should be:

"Vitamin B12 is an essential micronutrient that we all need in our diets," says Avena. "B12 shots can help you to feel more energetic, fight lethargy, and can also help with mood."

B12 Helps Maintain a Healthy Weight

Michele credited B12 injections for weight loss, and she might be onto something. Avena says that B12 does a good job in "supporting your metabolism," which may help your body burn calories more effectively.

It has also been credited by some with improving sleep quality, increasing concentration, lifting your mood, fighting off infection, and boosting your energy levels, though again, more research is needed.

It Can Help Prevent Hair Loss

If that list isn’t impressive enough, you’ll be surprised to know that B12 deficiency has also been linked to hair loss; supplementation may, thus, help, though more research is needed. An injection alone won’t be enough to completely cure thinning hair, but it’s one of several factors that may potentially help.

B12 Shot Helps Those With GI Issues

For some people with certain conditions, a B12 shot may be their best bet for absorbing the B12 vitamin. "Most people can take an oral B12 supplement, but a small percentage of people can't absorb B12 in their GI tract, often because of an underlying condition such as Crohn's disease or other GI illnesses," says Levitan.

B12 Shots Are Convenient

vitamin b12 capsules in hand

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B12 shots can also be much more convenient than a pill. Instead of having to remember to pop a capsule every day, you only need one monthly appointment. The B12 shot is injected into your muscle, most often the upper arm, thigh, or buttocks. A health professional, such as a doctor or nurse, will administer the shot at the office or clinic. If you prefer, you can also talk to your doctor about teaching you to administer your own shots at home.  

Are There Any Side Effects?

Side effects are rare, but there are a few to be aware of. A slight sting is a given with any injection, but there are several other side effects you might have to deal with after a B12 shot. "Redness and pain at the injection site, headaches, pain in joints are some side effects that are reported," notes Avena.

If you experience other side effects, including the feeling that your body is swelling, a rash, dizziness, headaches, fever, and infection around the jab site, then you should contact your doctor. The more severe side effects—irregular heartbeat, shortness of breath, and muscle cramps—are rare, but you should immediately contact emergency services if you experience them.

Where Can I Get an Injection?

In the U.S., your primary care doctor can test your levels and administer them in the office. Some local pharmacies also offer them.

As far as how often you get them, it depends on your specific needs. "The schedule of administration is something that will depend on your medical situation and how deficient you are, so you should talk about it with your doctor," says Avena. "Some regimens call for daily shots for about a week, and then monthly after that, while others find a shot every few months works for them."

Article Sources
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  6. Wajih Ullah M, Amray A, Qaseem A, Siddiqui T, Naeem T. Anaphylactic reaction to cyanocobalamin: a case reportCureus. 2018;10(5):e2582. doi:10.7759/cureus.2582

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