Healthy Bananas is a premium upgrade for the Banana Farm in Bloons Tower Defense 4 and Bloons Tower Defense 5. It costs 15 in BTD4, 15 in BTD5, 4800 in Bloons Tower Defense 5 Deluxe, 1000 in Bloons Tower Defense 5 Steam and $0.99 USD in BTD5 Mobile. When a round ends, you get as many lives as upgrades on the Banana Farms plus one for the Farm itself (multiple farms also means more lives).
This Premium Upgrade allows for one of the only ways to let a M.O.A.B. Class Bloon through a level and still have lives to spare (the others being More Lives, Support Chinook and Triple Lives). If the player can save up enough lives, there will still be some left over if a MOAB-Class Bloon is let through. However, you'd need to save up 16,657 lives to let a ZOMG escape with 1 life remaining.
- As players share their lives in Co-op Mode, the player also benefits from the team-mate's Healthy Bananas, and the upgrade itself affects both player's Banana Farms.
- In an Odyssey, the fact that the player has one set of lives becomes an advantage with Healthy Bananas, because the player can get 30,000 lives or more if they are extreme banana farming throughout an entire hard Odyssey.
- Healthy Bananas will not generate lives in Impoppable difficulty, but will in Covert Pops and Daily Challenges only gives the player 1 life but allows Banana Farms.
This reappears as a Monkey Knowledge Point in version 15.0 in the Support MK Tree. It allows Marketplaces to gain +1 life per round, and Central Markets and Monkey Wall Streets to earn +3 lives per round. It can be unlocked after investing 8 points in Support MK Tree and requires an one-off purchase of 500.
- The Healthy Bananas MK in BTD6 is far weaker than in BTD5 Flash or BTD5 Mobile.
- The Version 15.0 update log's description for Healthy Banana was 'Marketplaces stock fresher bananas with no added DDT'. This is likely a play on the DDT Bloon and the pesticide that shares the same name with it.