My mom has dementia and is in a memory care facility. How do they get her to eat?

My mom has dementia and is living in a Memory Care facility. She is petite and has never been very big, but over the last several months, she seems to have given up on eating. She says, "I eat!", and maybe she believes that, but she doesn't eat enough! She'll take 2-3 bites and say she's full. Or she'll say, "I'll eat later" but never does. She is losing weight and looks very unhealthy now. How do we convince her to keep eating so she can keep her strength up? Has anyone else dealt with this?