Nanotech upgrade
On Planet Tabora,(the desert place) after you repair your ship, there's a path on your left, if you're standing near your ship. That path is the path leading to the Glider. As soon as you pass the arch, you'll see some fire spitting leeches. Look on your right and you'll see part of the first Glider course you have to pass when you get your glider. If you look closer, on one of the glowing blue thingies has a Nanotech health upgrade that looks like a blue hourglass spinning in something. Jump with the Thruster Pack and get it. Tada! Your health is instantly increased! Unfortunately, there isn't a way to get back up, so please do that before doing anything else.