There is no evidence that vitamin B-12 shots are beneficial for weight loss, as stated by Mayo Clinic. Despite the lack of any scientific studies indicating that vitamin B-12 supports weight loss, some weight loss clinics do include vitamin B-12 injections as part of their therapy programs.
Vitamin B-12 injections are not likely to cause any health problems, reports Healthline. Vitamin B-12 is a water-soluble vitamin found naturally in animal proteins, states MedlinePlus. Good food sources include meat, poultry, eggs, milk and shellfish. Vitamin B-12 plays an important role in protein metabolism and helps maintain the central nervous system. A vitamin B-12 deficiency can cause pernicious anemia, weakness, loss of balance, and tingling or numbness in the arms and legs.