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Supplements

B12 injections

Vitamin B12 shots treat B12 deficiency; they are often sold for energy and weight loss, but they have not been shown to cause weight loss.

Clinician review pending Updated Supplements
DefinitionVitamin B12 shots treat B12 deficiency; they are often sold for energy and weight loss, but they have not been shown to cause weight loss.

What it means

Vitamin B12 is needed to make red blood cells and keep nerves healthy. Shots are an established treatment for people who cannot absorb B12 well, such as those with pernicious anemia, after some stomach or weight-loss surgeries, or with low levels from long-term metformin use.

Some weight-loss clinics add B12 shots to programs or mix B12 into compounded GLP-1 products. In people with normal B12 levels, there is no good evidence that extra B12 speeds weight loss or raises metabolism.

Eating less on a GLP-1 medicine can lower vitamin intake, so diet quality matters. A blood test is the way to know if you are low, rather than guessing.

B12 is generally safe, but injections still carry the usual risks of any shot. Compounded mixtures of B12 with GLP-1 drugs have not been studied in the trials behind approved products.

Why it matters

B12 helps people who are deficient, but it is not a weight-loss treatment.

Related terms

MetforminLipotropic injections (MIC shots)NAD+ injectionsDoes B12 help with weight loss

Sources

  1. NIH Office of Dietary Supplements: Vitamin B12

Clinician review pending. Drafted from primary sources and waiting for sign-off by a licensed clinician (MD, DO or PharmD) before launch. Every number is checked against its source. Drug facts are re-checked quarterly, prices monthly and whenever a label changes. How we review · Report an error