You're on a keto diet
Just like how going super low-carb makes your breath reek, it can do the same to your pee. When you enter a state of ketosis, usually by purposely forgoing almost all carbs and going on a keto diet, your body releases ketones as it burns fat for fuel. This is great for weight loss, but not so great for your body odor. And if you're a type 1 or type 2 diabetic who takes insulin, ketones could also affect your urine if your insulin levels are off, and there's not enough glucose for your body to use, Dr. Ellerkmann explains.
Maple syrup urine disease (MUSD)
Yes, there's actually a disease for your pee named after the sweet breakfast condiment. Maple syrup urine disease is an inherited condition in which the body can't break down certain amino acids properly, and creates a sweet smell in the urine. Dr. Ellerkmann has described it as smelling like maple syrup, burned sugar, or malt. It's pretty rare, and since it's genetic you'll see it in infants and other young kids. If you're a parent and your kid's pee starts smelling extra syrupy, get it checked out, because untreated, it could lead to seizures, coma, and death.