It gives you energy, and it helps better than anything else to fight a cold, except resting. It is the citric acid in the lemon. Citric acid is a powerful germicide.
I am for this because lemon juice also reduces your hunger. Even lemon juice in water, it prevents
the stomach from inflating as much when eating which makes you feel full sooner so you eat less. I
believe some people drink it to lose weight, or to help them lose weight.