This is a fun and interesting implementation of the Snake genre. I like that the player gets a break or reset from being super long, but we get wider! I didn't even think to interpret "old" as time or age to use as a mechanic, and having an obstacle to dodge but later becomes a desired pickup is fun. Forcing a complete restart on colliding with a wall or yourself is brutal and kinda unfun, but having multiple lives and retracting a bit is a nice solution. I didn't exactly understand the chopping your body in half and then being able to quickly eat some of it back up. Seemed like I'd get myself trapped and bonk a number of times until I lost.
Fun and intriguing take on such a simple seeming genre. Great work, keep at it!