How can I get my parent to eat without nagging?

The short answer is that in this situation there's only so much you can do. As caregivers, we see food as love. And when the person we're caring for is losing weight, in our minds food becomes medicine, too. Of course you desperately want your father to eat, and you're spending lots of time trying to think of the right thing to cook -- and then it's so frustrating when he doesn't want to eat it, or can't eat much of it. I see this all the time.

I suggest starting by talking to your father openly about your concerns and asking him what solution he thinks would work best for him. I did this recently with a cancer patient and he came up with a solution that worked really well. We asked him what he'd like to eat and he said he just couldn't predict ahead of time what would seem appetizing to him. He asked if we could prepare small amounts of lots of different things and then he could see what he felt like eating when he was ready to eat. Of course this can seem daunting since it's more work for you, but you can freeze and store portions so there are lots of selections at any given moment.

Another solution: Try not to be attached to how much your father eats. If you've made the food available, that's the important thing, and that's how you can show your love. Beyond that, you have to let go of it. It helps to keep reminding yourself that your father is battling with his appetite too. He knows he needs to eat, and he can't help it that suddenly things taste awful or he feels sick and doesn't want food. During cancer treatment, the body's need for food changes. Keep in mind that chemotherapy is very hard on the body, and it's under tremendous strain. You're introducing a foreign substance into the system and you can't do that and then expect it to react as usual. Your job is to provide supportive care to help his body get through this.