As your grandpa will tell you, baking soda is a decent abrasive whitener. But brushing the powder straight onto your teeth can cause major irritation and long-term enamel erosion. Make sure it’s well diluted in a homemade paste with vegetable glycerine and some dissolved xylitol as your cavity-fighting sweetener. You can also cut the top off an organic strawberry and rub the berry on your teeth. The inside of an orange peel works too, according to TV docs. What the prime time tips don’t share with viewers is that you should use both techniques sparingly and rinse and brush right after any homemade teeth whitening since it can erode your enamel. Need I remind you that enamel doesn’t grow back, and that enamel erosion will make enjoying things such as, oh, ice cream or coffee seriously uncomfortable? Unless that sounds enticing, I’d stay away from harsher enamel-busting lemon remedies in particular.