Health is a game mechanic in The Last of Us. Any time Joel takes damage from an enemy, he will lose some health. If the health bar depletes, he will die.
Pre-release appearance
In the E3 game demo, Joel's health bar was shown at the top left screen, represented by a green bar. Any time Joel takes damage, part of the bar changed to red to show how much health was lost, before disappearing. A light green bar shows how much health Joel will recover while using a Health kit, with a smaller bar underneath to show the process of healing. Unlike the newer health bar, it does not change color depending on how much damage Joel has taken.
In-game Appearance
The health bar is seen at the bottom right corner, next to the weapon icon. When Joel takes damage, the bar will shrink, and the color will change from green to yellow, orange, and red. The health bar will blink in red to alert the player that Joel's health is low. Tunnel vision will also be shown in red, but this is only seen during combat. Joel can increase his health by upgrading the Maximum Health skill two times. The bar will be longer, circling around the weapon icon.
Ways to Heal
Health Kit
The health kit is the most efficient way to recover lost health. Training Manuals can be used to decrease the time it takes to heal and to recover more health.
Food
They come in three sizes; small, medium, and large. They repesent canned food and energy bars. They instantly restore health when Joel picks them up, but do not restore as much health as a health kit would.
Multiplayer
In Factions, the health bar is the same, although it cannot be upgraded to have more health. When it empties, the player does not immediately die, but instead becomes downed. When a player becomes downed, they can crawl to nearby teammates to be revived, but they have a limited time to do so before bleeding out and dying (bleed-out time is represented by a depleting red bar surrounding a cross symbol above the down player's head).
As with in singleplayer, players can replenish health through using health kits, which spawn at various locations throughout the map and can also be crafted. Injured players may sometimes find food in lootboxes, which can also be consumed to regenerate health.
The First-Aid Training skill allows players to heal faster when using health kits. Levels 2 and 3 of the skill allow players to heal teammates. The Reviver skill brings downed players back to life faster, and also grants them more health on reviving.