One order of one Mcdonald's medium fry contains a whopping 320 calories.
So if you eat a lot of those fries from Mcdonald's then you could gain a lot of weight but in moderation the Mcdonald's fries are okay to eat.
However for those people claiming that Mcdonald's fries and other foods made them fat and then they sued Mcdonald's they should remember that Mcdonald's didn't force them to eat their food nor do they force them at all to eat their food.
It was their own fault if they gained weight from the Mcdonald's food because you have a choice whether to eat their or not.
But I've eaten and still eat Mcdonald's fries at least once per week along with a Big Mac burger from them and never have gained weight and I'm still pretty healthy.