During chemo I totally lost my appetite and for a few months after food just tasted bland. I forced myself to drink 4 - 6 ensures a day, drank 80oz of water and 1 or 2 glasses of pedelite. Any thing else I could squeeze in was great. I made smoothies with pea protein and frozen fruits too.I lost 35 lbs even with all that. But I at least knew I was getting in my nutrients. Best of luck!

I think I'm the only person who CRAVED food while undergoing chemo/radiation, then immunotherapy. I think I gained 35 pounds during that time. Weird, huh? Always overweight, but that was ridiculous!!
Have you ever tried Ka'Chava protein shakes? You mix with cold water and ice. Very nutritious. Packed full of what we need to heal. (There's a 10% off coupon on their site) I love them for breakfast..Those will help ya put that weigh back on, you can add fruit in them too. God bless you.

Cold smoothies are good too. It may some experimenting to find things that at least taste ok and he can eat. It's pretty common for cancer meds to cause food to taste "off" or lose the ability to taste (kinda like covid). Different people find different flavors (even those they may not have liked before) may taste good with the changes. Spicy, sweet, sour, bitter or salty. So maybe try some small snacks to try different things and see if certain tastes are more acceptable.

Example, if he likes tuna, mix up some tuna and serve with crackers. Let him him add hot sauce, salt, sour pickles, sweet pickles, or argula lettuce and try them. Do some appeal more than others? Then build from there.

Temperature and texture can help too. Is cold or hot easier to get down? Is tender vs chewy easier? Creamy or not? Keep trying until you find things that'll get him through.

Sometimes it can just be mind over matter. You know you have to eat so you just get it over with lol.