01 burning to much oil

i have an 01 and i check the oil about 500 miles before i need a change. I keep having to add oil every time up to 1/2 a quart of oil each time. I have checked the car and have no leaks, could there be something wrong internally with the engin that would make it burn more oil. Thanks for your help.

Does your oil smell like fuel? Is there any smoke, and if so what color is it? Look at your spark plugs, they should be a golden color. I'll have a better idea if you can answer those questions.

If each answer is no, you might need to change your valve seals.