My gums always bleed in between my teeth what is this?

You could have: Gingivitis. Do you brush 2 x/day and floss every day? Have you seen your dentist within the last six months? I would encourage you to see your dentist for further evaluation. Take care.

Diet?: If this is a problem all over the two most common reasons are not flossing and/or poor diet. Poor diet is a common finding in young people feeding themselves and not eating enough vegetables. If the problem is one spot, you have a cavity, chipped tooth, or something stuck between your teeth.

Sign: Bleeding gums is a sign of gum infection. If you are not cleaning between your teeth daily w floss/water-pik/interdental simulator/proxi-brush/rubber tip, and if you are not having teeth cleaned @ dentist's office regularly, gums may be infected. Another cause is systemic disease, such as diabetes. Please call your dentist for rx. The sooner he sees you, the sooner he can reverse the disease.

Gingivitis...: ... or if more advanced, periodontitis. Can't possibly tell over the internet. You'll need to call a local dentist for an appointment. Left untreated, periodontitis usually results in the loss of your teeth.