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Do vitamin B12 shots for weight loss really work plus other benefits of B12 shots

Vitamin B12 definiens are not identified in routine blood tests and go undiagnosed for years. Vitamin B12 deficiencies can cause fatigue, weakness and nerve damage.10

B12 Shots (Injections)

Vitamin B12, also referred to as cobalamin, is one of the eight B vitamins that is essential for maintaining a healthy nervous system, brain and liver. It also aids the formation of red blood cells.1

Vitamin B12 isn’t produced naturally in the body, so humans need to obtain it from their diet. While meat, shellfish, and dairy products are some of the best sources, there is a number of food products that are also fortified with vitamin B12.1

Vitamin B12 deficiencies were mentioned as early as 1849, and sometimes resulted in fatal outcomes.8

Despite these sources, much of the population is still considered to be at risk of developing a vitamin B12 deficiency.1 Risk of deficiency also increase as we age, as our stomach loses the ability to absorb vitamin B12 as effectively.7

Severe deficiencies may go undetected and lead to neurological problems, nerve damage or pernicious anemia, a condition where the stomach cells cannot absorb vitamin B12.2,7 Vitamin B12 shots are the most common and effective way to treat or prevent severe deficiencies.

B12 Shots for Weight Loss

Other than treating vitamin B12 deficiencies, there have been an increasing number of claims that B12 shots may help facilitate weight loss. The use of B12 injections for weight loss has gained popularity as being a safer and more affordable method of losing weight than going under the knife.

But do B12 injections help lose weight for everyone? Vitamin B12 helps the body convert carbohydrates into glucose, or energy for the body to use. It also assists the body in metabolizing fats and protein. It’s not uncommon for older adults to be mildly deficient in vitamin B12 which can cause symptoms such as light-headedness, weakness, fatigue or shortness of breath.2,7 These symptoms that may impair physical activity or reduce the motivation to work out. For those who are deficient, receiving B12 injections may help support a normal metabolism and sustained energy levels.

Individuals who have diabetes, eating disorders, HIV, Crohn’s disease, recently undergone weight loss surgery or adhere to a vegan or vegetarian diet, are at increased risk of vitamin B12 deficiency.7

Many people who regularly take B12 shots to lose weight say the injections speed up metabolism, which in turn helps burn more calories and shed those unwanted pounds faster.

However, for those who receive enough vitamin B12 in their daily diet, receiving b12 shots for energy or weight loss will likely not influence the body.3

Benefits of B12 Shots

Other than deficiencies, what are B12 injections for? As an increasingly popular form of supplementation, vitamin B12 shots have been investigated for their additional health benefits. Thanks to new research, additional B12 shot benefits have been discovered.

  1. Increased Energy
  2. Preliminary studies have noted that vitamin B12 shots may help support increased energy. While scientists have traditionally thought these effects were only for patients with a previous deficiency, one study has noted that subjects who are not deficient may experience increased energy, as well.7

  1. Promote Heart Health
  2. Vitamin B12, along with vitamin B9 and B6 help naturally reduce high levels of homocysteine, an amino acid. At high levels, homocysteine has been associated with an increased risk of coronary heart disease and stroke. Doctors may recommend increasing intake of B vitamins if you are concerned about heart disease.7

  1. Reduce Symptoms of Chronic Fatigue Syndrome
  2. Chronic fatigue syndrome (CFS) is a condition that effects the patients’ mood and everyday function. While the cause is not known, symptoms include muscle pain, trouble sleeping, headaches, extreme fatigue and issues with concentration or short-term memory.9

    In one study, vitamin B12 shots that contained 2,500-5,00 mcg was given to CFS patients every 2-3 days. Of over 2,000 patients 50-80% of the patients reported improved well-being, energy and stamina within three weeks of treatment.9

  1. Improve Mood
  2. In the body, vitamin B12 works with folate to produce a compound known as S-adenosylmethionine (SAMe). The compound is important for regulating mood.7 For users that are deficient, irritable moods or depression is often reported. Increasing vitamin B12 levels through intramuscular injection may help improve overall mood.

  1. Reduce Allergy Symptoms
  2. Anecdotal reports note that vitamin B12 injection may help manage or reduce allergies. However, scientific research on vitamin B12’s effects on allergies is still ongoing.

B12 Shots Side Effects

Currently, there are no known negative side effects of B12 injections. As a water-soluble vitamin, any excess vitamin B12 is excreted out and large doses are not likely to cause harm.3 B12 shot reactions may vary among individuals and cause a mild pain or bruising at the injection site. In rare cases, individuals may have an allergic reaction to B12 injections.5 Seek immediate medical attention if you experience throat or tongue swelling, severe rash, shortness of breath or lightheadedness.

Are B12 injections safe during pregnancy? Generally, vitamin B12 injections are considered safe for expectant mothers, particularly for those with a B12 deficiency. Having a vitamin B12 deficiency during pregnancy can be dangerous for a baby’s health, and may lead to neural tube defects or other neurological problems.6 However, always check with a health care provider prior to treatment.

Vitamin B12 injections may also interfere with the effectiveness of some medications. If you have any chronic conditions or take prescription medication, consult with a health care beforehand.4

How and Where to Give B12 Shot

To save a trip to the clinic, it’s becoming increasingly common for people to give themselves a B12 shot. Users can ask their health care provider to provide a demonstration on how to properly perform the B12 injection. Users should not attempt to do B12 injections at home without proper training.

Before giving a B12 injection, you will need to determine where to administer the shot. The three most common vitamin B12 injection sites are the shoulder, the hip, and the thigh (most common for self-injection). Some people also prefer to get their B12 shots in the stomach, as there is generally more fat which helps minimize the pain. Getting B12 shots in the buttocks isn’t recommended though, because there are major blood vessels there that could be damaged if accidentally injected.

After choosing the injection site, follow these steps on how to give a B12 shot:

    1. Clean the injection area using rubbing alcohol on a cotton ball. Allow the site to dry.
    2. Use a new cotton ball (that is dipped in rubbing alcohol) to clean the surface of the container with the B12 solution. Allow it to dry.
    3. How often can you get a B12 shot? Users typically receive an injection once a month, unless otherwise advised by a health care provider.
    4. Turn solution container upside down and insert clean needle into surface of container. Pull on the plunger to withdraw proper vitamin B12 injection dose into needle chamber.
    1. Use thumb and forefinger of non-injection hand to hold skin of injection site tight.
    2. Inject needle at a right angle.
    3. Hold needle in place and push down on plunger to insert all of solution.
    4. Remove needle at the same angle of insertion.
    5. Apply pressure with cotton ball to stop any bleeding.

How long do B12 shots last? Since vitamin B12 is water-soluble, determining how long does a B12 shot last in your system depends on body composition, water intake and how often you exercise. Typically, vitamin B12 is absorbed within 24 hours and excess amounts are eliminated through urine within 1 to 6 days.

B12 Shots Dosage

The B12 injection dosage that a person should take varies depending on their health circumstances, but doctors typically administer B12 shots in doses of 1000 mcg. Of this 1000 mcg dose, your body retains roughly 15 percent (approximately 150 mcg).

Where to give a B12 shot including directions on how to give a B12 shots or B12 injections at home

When giving B12 injections at home, use our easy to follow guide for step-by step instructions on how to give a B12 shot.

Can I Buy Vitamin B12 Injections Over the Counter or Online?

Because B12 injections are relatively safe, purchasing them is quite easy and there are many options that you can use to buy B12 injections. If you prefer shopping from the comfort of your own home, you can buy b12 injections online. Although buying B12 shots online is relatively safe and convenient, it’s recommended to consult with your doctor before purchasing.

If you decide to get your B12 shot administered by a health professional, B12 shot cost may range from $20-$80 depending on location. Certain clinics claim to offer free B12 shots if you purchase a certain amount from them.

Scientific Research Referenced in this Article

  1. Baik, H.W & Russell, R.M. (1999). Vitamin B12 deficiency in the elderly. Annual Review of Nutrition. 19, 357–77doi:1146/annurev.nutr.19.1.357
  2. Reynolds, E.H. (2014). The neurology of folic acid deficiency. Handbook of Clinical Neurology. 120, 927–43. doi:1016/B978-0-7020-4087-0.00061-9
  3. Bauer, B.A. (2015). Are vitamin B-12 injections helpful for weight loss? Mayo Clinic Expert Answers. Retrieved on October 5, 2017 from – View Reference
  4. Ehrlich, S.D. (2007). Possible Interactions with: Vitamin B12 (Cobalamin). University of Maryland Medical Reference Guide. Retrieved on October 5, 2017 from – View Reference
  5. Hovding, G. (1968). Anaphylactic reaction after injection of vitamin B12. British Medical Journal3(5610), 102. Retrieved November 24, 2017 from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1986048/?page=1
  6. Dorothy J. VanderJagt, Innocent A. O. Ujah, Eugene I. Ikeh, et al. (2011). Assessment of the Vitamin B12 Status of Pregnant Women in Nigeria Using Plasma Holotranscobalamin. ISRN Obstetrics and Gynecology. 2011(365894), 1. doi:5402/2011/365894
  7. University of Maryland Medical Center. (date). Vitamin B12 (Cobalamin). Retrieved November 24, 2017 from – View Reference
  8. O’Leary, F., & Samman, S. (2010). Vitamin B12 in Health and Disease. Nutrients, 2(3), 299-316. doi:3390/nu2030299
  9. Werbach, M. R. (2000). Nutritional Strategies for Treating Chronic Fatigue Syndrome. Altern Med Rev, 5(2), 93-108. Retrieved November 24, 2017 from https://www.spectracell.com/media/uploaded/2/0e2019149_265fullpaper2000altmedrevnutritionalstrategiesfortreatingchronicfatiguesyndrome.pdf
  10. Goodman, K. (2017, January 31). Can B12 shots boost my energy and help me lose weight? Retrieved November 27, 2017 from – View Reference
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