glutton, gluten

Glutton or glutton means someone who habitually overeats, or who consumes food rapidly and greedily--
He loaded his plate and shoveled in the food, like a real glutton.
He behaves like a glutton when we go to an all-you-can-eat restaurant.
Glutton is sometimes used figuratively--
He's still at work? What a glutton for punishment.

Gluten or gluten means the protein found in wheat flour or some other grain products--
Wheat, rye and barley all contain gluten.
Diets without gluten are becoming more popular.

Now that you know that, you can say--
"He usually eats like a glutton, but now he's avoiding gluten, and can't have bread or pasta."

Note--"gluttony"means overeating or eating greedily--
Gluttony is one of the traditional seven deadly sins.
"Gluttonous" describes the eating habits of a greedy eater, or someone who overindulges regularly--
His table manners range from picky to gluttonous.
Note # 2--"glutinous" describes something sticky--
You will like that better if you make it with glutinous or "sticky" rice.