In fact any tea for that matter. I sat at a sushi train restaurant sipping my hot tea and chowing down on salmon when suddenly I felt vilently Ill.
Rushing off to the bathroom I wondered what caused it. The nausea lasted a good 2.5 hours. I finally made the connection that it was the tea! Pitty, it was good sushi.
Green tea and black tea contains tannin. When adding boiling water to tea the first 30 seconds releases caffine, the next 2mins releases the tannin. The longer you brew the stronger the tannin leaving a bitter taste.
On an empty stomach tannin will create an almost instant need to vomit.It’s the same with red wine which has more tannin than white
To counteract this, you can add heavy cream or full fat milk,however it’s best to drink tea after and during food.
You can read about tannin sensitivity here, and how to beat it.