Hair loss can occur for a number of different reasons, including a poor diet. Not getting enough of certain nutrients, such as iron or vitamins B-12 and D, can interfere with hair growth. Vitamin B-12 shots will only be helpful for treating hair loss, however, if that hair loss is due to a deficiency of this vitamin.
Vitamin B-12 and Hair Loss
You need vitamin B-12 to form DNA, nerves and red blood cells. If you don't have properly formed red blood cells, they don't carry as much oxygen. A lack of oxygen can cause your hair to grow slowly or fall out. A vitamin B-12 deficiency could also cause scaling or dandruff. Hair loss associated with a vitamin B-12 deficiency would cause your hair to be thinner all over your head, not just in certain spots.
Symptoms and Treatment
Vitamin B-12 deficiency isn't common, as only 2.4 micrograms per day is enough to meet your needs. Besides hair loss, a B-12 deficiency can cause fatigue, constipation, numbness in the extremities, dementia, depression, balance issues and a sore mouth and tongue. Deficiencies are usually treated with vitamin B-12 shots because this bypasses any potential absorption difficulties that could be responsible for the deficiency, although high doses of oral vitamin B-12 may be effective as well, according to the Office of Dietary Supplements.
Who's at Risk
People with a condition called pernicious anemia can't absorb vitamin B-12 from food and usually need regular vitamin B-12 shots to maintain healthy levels of this vitamin. Those who take the diabetes medication metformin or medications for gastroesophageal reflux, those over 50 years old, strict vegetarians and people who've had weight-loss surgery are at an increased risk for vitamin B-12 deficiency. The same is true of those who suffer from digestive disorders including Crohn's disease or celiac disease.
Hair loss is often due to other causes and not a vitamin B-12 deficiency. These include heredity, stress, certain medications, menopause, cancer treatments, illness or underlying medical conditions. In these cases vitamin B-12 shots will have no effect on hair loss.
Vitamin B-12 shots can have side effects, including diarrhea, allergic reaction, swelling, fever, muscle cramps, bruising, sore throat and chest pain. Speak with a doctor right away if you experience any bothersome side effects after getting a vitamin B-12 shot.