MOLINE, Ill. — Lois E. Florence recently left her doctor’s office with a diagnosis of colitis, an intestinal disorder, and a complicated set of instructions for changing her diet.

After several setbacks she had a chance conversation with the pharmacist at her local Hy-Vee grocery store here that changed everything.

He referred her to the store’s dietitian, Dawn Blocklinger, and on a recent sunny morning, the two of them spent almost an hour compiling a list of the foods Mrs. Florence, 79, could eat and alternatives for the ones she couldn’t, like rye bread to replace wheat and Tofutti instead of ice cream.

Then they went shopping.

Hy-Vee is the only grocery chain in the country that posts a registered dietitian in almost every one of its 235 stores. In rural areas, some of its more than 190 dietitians serve a cluster of stores.