Bags under the eyes are caused by moving fat deposits and accumulated fluid, according to Mayo Clinic. They become more common as someone ages and the muscle tissues around the eyes weaken, causing the skin to sag.
Fluid accumulates under the eyes for multiple reasons, states Mayo Clinic. Hot, humid days, hormonal changes and eating salty foods can cause the body to retain more fluid everywhere, including around the eyes. Lack of sleep can create or worsen bags. The eyes can get swollen and puffy due to allergies or dermatitis, and some people can inherit dark under-eye circles from their families.
Puffy bags beneath the eyes rarely indicate a more serious condition, states Mayo Clinic. Instead, they are usually cosmetic issues. Cool compresses can reduce swelling. If the puffiness is a symptom of allergies, medication can reduce the severity of the symptoms and cause the puffiness to go away. Laser surfacing and chemical peels improve skin tone and tighten the skin, reducing the darkness and puffiness.
Sleeping with the head slightly elevated helps the fluid to drain away from the eyes, suggests Mayo Clinic. Getting seven to eight hours of sleep at night and applying a cold compress to the eyes with mild pressure for a few minutes can help reduce or eliminate puffy or dark eyes.