Food is bitter

Hi Murshed and welcome. It's just time I'm afraid. Food becomes simply fuel for weeks. For some of us by six to twelve weeks after treatment some taste can start to return. For others is can take months. How far into treatment is he?

Hi Murshed. Yes bitter  or metallic is very common. He can try plastic utensils to eat with. Although ti be honest the best way is food is fuel and if he can eat it’s a bonus. Takes a good while in many cases for taste to return. 
Hazel 

Hi Murshed. Sorry to hear that your neighbour is suffering. Strange tasting food happens to all of us who have imrt and he will probably temporarily lose all sense of taste before too long as the RT burns off his taste buds. The solution is, I think, to avoid foods which taste bad and just concentrate on those you can manage. People in here will tell you that you must simply regard food as fuel and not necessarily something to be enjoyed, until your sense of taste returns at least.