Why was Adult Gohan drawn differently from Future Gohan?

[Rocketman]

Future Gohan went on a ride on his Harley, with Van Halen on the maximum volume

I knew there was a reason I liked him.


(Sup, guys)

[Tsukento]

As mentioned before, it's primarily because of the age difference and how they grew up. Gohan growing up as a kid trying to survive against two beings that have killed off more than half of the Earth's population all the way up to adulthood is obviously going to look different from the Gohan that ended up growing up during his teen years in a more peaceful time.

Remember that even Goku went through quite a bit of a body change when he grew up into an adult. People just tend to change a bit based on how they grow up. Another good example of this is to look at how different Future Trunks looks compared to End of Z Trunks.

[SylentEcho]

Another thing. Future Gohan is bulkier and his face is broader as compared to present Gohan. When you bulk up, you gain weight not only on the body, but the face too.

Plus their lifestyles were different. Future Gohan may have had to train a whole lot harder which may have given him more bulk. I'm sure if present Gohan bulked up, he'd look a lot like Goku too.

Another thing is, yeah Toriyama didn't think through what I mentioned above. He just changed his style of drawing by then. Plus he wanted to probably keep the characters unique. This is why Trunks looks different at the end of Z.

[Fox666]

I suppose the character passing the 18 years line is a leading change. Look at how future Trunks changed in the 3 years time-skip on his own time.