Ketogenic diets force your body to adapt to using fat for fuel when glucose (from carbs) is not present, this is known as ketosis. Ketones are a by-product of ketosis and keto sticks (also known as ketostix or ketosticks) are urine testing strips which detect the presence of ketones in the blood. They are small plastic strips with an absorbent pad on the end, you urinate on the absorbent pad and it changes colour to reflect the amount of ketones present in your urine.