How have others managed a 12-year-old high functioning autistic child with sugar cravings?

[Sanddunes]

Hello,

i have a 12 year old son with HF autism. We live abroad and he goes to a regular school. He has an addiction to sugary food. Has zero self-control and will absolutely NOT know when to stop eating. I have to lock all sugary food and can not store anything sweet in the fridge. He has been like this since he was 7/8 years old but it was easier to control him as he was younger. He has not been diagnosed with an eating disorder. As he is growing older he has found ways to get sweets (buys on his own when i am not with him). How have other parents dealt with this situation? Does it stop or gets worse? Any advice/strategies?

Has he been to the doctor and had blood tests done to check for diabetes and other health issues?

Yes. No other issues other than slightly higher triglycerides

I find chewing gum works, keeps their mouth busy for a while until actual meal times.