1 & 2: Digestive System — Eat less processed or junk food, reduce the amount of fat in your diet, step up water intake and opt for cooling things like cucumbers.
3: Liver — Cut out the alcohol, greasy food and dairy. This is the zone where food allergies also show up first, so take a look at your ingredients. Besides all this, do 30 minutes of light exercise every day and get adequate sleep so your liver can rest.
4 & 5: Kidneys — Anything around the eyes (including dark circles) point to dehydration. Drink up!