Hi, N.. Well, is your daughter losing weight? If so, get her to the pediatrician, quickly. When she's nibbling, she may be eating a lot more than you think she is. Also, does she go to daycare or anything? She may be eating at daycare or at her friends' houses, which will throw off her appetite at home. She may have been introduced to stuff that you do not serve at home, and so her tastes may have changed.
Bear in mind that children grow at different rates. Up until this point, her body has gone through a rapid series of growth spurts but may be slowing down now that she's hit 2 years old. When she starts growing again, her appetite will increase. Still, I would get her a physical, and explain to the pedi that her appetite has taken a sharp decline. Has her activitiy level also decreased? Make sure the doctor knows all the facts.
Now...are you, yourself, still a "grazer"? Lola may be picking up on your eating habits. At age 2, children are EXTREMELY aware of gender differences and are EXTREMELY concerned about appropriate behavior for their gender, so if she has gotten the message that ladies aren't supposed to eat very much, she may be trying to be the best lady she can be.
Has anyone teased her about her super-healthy food, or made fun of her while she's eating? If so, this may have affected her and made her feel strange about eating. See if you can coax it out of her the reasons why she doesn't want to eat much of anything.
If I were you, I would be concerned as well. I hope she's fine and everything works out for the best.