The alternative was to remove the thyroid and replace the hormones with synthetic. Unfortunately you body needs different amounts for different things at different times of the day. It is a constantly moving target and in many cases you never really feel right again.
The special diets were known to the Graves community when I started 8 years ago. Later on I learned and incorporated microbiota theory and used that as a basis for experimenting which has worked well. I only recently started intermittent fasting and feel even better for it.
Interestingly I started intermittent fasting after reading Nassim Talebs book Anti-fragile. He and I share the same opinion on the medical establishment (I won't bore you with my details) so I figured I'd give it a go and it helps.