A strong immunity system plays a great role in healing acne marks. Building a strong immunity system involves eating a healthy diet and taking care to build a healthy lifestyle to help heal your acne marks properly and quickly. It is however to be realized that the bigger the acne, the longer the red mark it leaves takes to heal. Some of the remedies that have really helped is drinking sea water and bathing the acne, as sea water is healthy for both the skin and the inner body. Moderate sunlight could help heal acne provided you have a good immunity system and eat healthy
However the bottom line always remains that the healing time for acne greatly depends on the strength of your immune system.