This was the first genetic disease for which a routine screening test became available. Persons having this genetic defect must monitor their intake of phenylalanine. For this reason, products containing aspartame carry an information label for phenylketonurics. Methanol is commonly encountered in the diet. The table below shows the amount of methanol you would get from a can of diet soft drink, along with amounts found in the same volume of several fruit juices.
Methanol is well known to be poisonous in large quantity.
Your liver can deal with reasonable quantities of methanol, metabolizing it so that it can be excreted. If you start drinking enough methanol to get inebriated, you overwhelm your liver's metabolic machinery, and serious problems result. I know exactly how it is handled in the body. I have no reservations about letting my kids or my parents use it. It was December, 1965.