system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can food be considered 100% but there are other ingredients?

For example, ReaLemon lemon juice says 100% lemon juice on the front, but on the back the first ingredient is water? Followed by lemon juice and preservatives.
gpt
There is a big difference between “made of” and “made with.” If something says made with 100% lemon juice, that just means 100% lemon juice is one of the ingredients. If it’s made of 100% lemon juice, it had better be lemon juice.