Eyes get puffy after crying primarily due to fluid retention in the tissue around the eyes. When crying, the lacrimal glands produce a large volume of tears that overwhelm the eye's drainage system, causing excess tears to spill out and be absorbed by the surrounding tissues. This leads to swelling or puffiness as the tissues retain this extra fluid. Additionally, emotional tears have a higher water content and lower salt concentration, which causes water to move into the saltier eye tissue by osmosis, further contributing to puffiness. Inflammation of the lacrimal glands from overactivity during crying can also cause swelling.
In summary:
- Tears overflow because the tear drainage system can't handle the increased volume.
- Excess tears are absorbed by under-eye tissues, causing fluid buildup and puffiness.
- Osmosis causes water from the tears to enter saltier eyelid tissues, worsening swelling.
- Lacrimal gland inflammation may add to the swelling after crying.
This puffiness is usually temporary and goes away by itself after the tears are reabsorbed.
