I too have been diagnosed with HC. I’ve found substantial relief by avoiding gluten, minimal dairy, sulphites/sulfites, nitrates, tomatoes and peppers, avoid all sugar. When eating fruit, I must eat with fat. I also follow a high fat diet - good fats, olive oil, coconut oil, ghee. I have brought down my flares from 18 days a month to around 5-6. Base line headache improved too.