cuttiiee says:

Your skin will stretch when you gain and lose weight; that includes your tattoos. Losing weight will probably make sections darker and gaining weight could make the black turn blue! That’s what the tattoo artists told me anyway.

Kimberly B says:

Concentrate on getting your body in the best condition it can be in. Arm tattoos are popular because they are a part of the body that doesn’t change as much as, say the torso, so while they wont be as different as if you lost weight there, it will definately probably alter somewhat. Focus on toning your arms and legs while losing weight, and this will reduce the problem. If your arm is about the same size except with muscle instead of fat, you will have less loose skin. Also, remember to give your skin a year to catch up with your weight loss after you have reached your goal, and eat lots of fish to help along the process.
No matter what happens, a good tattoo artist can fix you up again. Work on your body, your tattoos can be saved, and your health is more important!

wickedma says:

You might have to get it recolored.