Obviously, bad dental hygiene can lead to cavities and gum disease, but here's a list from Health.com of eight surprising things that can also be bad for your teeth.

 #1.)  Bottled Water.  About 60% of people in the U.S. have fluoride in their tap water, but most brands of bottled water don't.  So if you ONLY drink bottled water, you might not be getting enough fluoride to protect your teeth from cavities.

 #2.)  Sports Drinks.  They usually have a lot of sugar and a high level of acid, which can wear away your enamel.  And the same goes for soda, coffee, and wine.

 #3.)  Diabetes.  It lowers your body's resistance to infections and puts you at risk for developing gum disease.  So if you're diabetic, brushing and flossing is even MORE important.

 #4.)  Cigarettes.  Obviously, they can stain your teeth yellow, but a lot of smokers don't realize that the tar from tobacco sticks to their teeth and acts like glue for bacteria, which can cause tooth decay and gum disease.

 #5.)  Pregnancy.  Estrogen and progesterone levels skyrocket when you're pregnant, which can cause inflammation of the gums and lead to gingivitis.

 --And birth control pills can do the same thing because they basically just make your body THINK it's pregnant.

 --Also, if you're pregnant and you have morning sickness, the stomach acid can cause tooth decay.  So after you get sick, you're supposed to brush with baking soda or baking soda toothpaste to neutralize the acid.

 #6.)  Prescription Medication.  A lot of prescription pills, over-the-counter pills, and even diet pills can cause dry mouth, which puts you at risk for gum disease, tooth decay, and cavities.

 #7.)  Dieting.  When you don't get enough vitamins and nutrients, it increases your chances of developing infections, including periodontal disease.

  --So when you're on a diet, it's especially important to get enough B vitamins, calcium, protein, vitamin C, and folate, which is mainly found in leafy green vegetables.

 #8.)  Brushing Right After You Eat.  If the food is acidic, brushing can cause erosion of your enamel.

 --So if you eat or drink something with a high level of acid . . . like wine, coffee, citrus fruit, or soft drinks . . .  you're supposed to wait an hour before you brush.