What kind do you use? My husband was using Isosource 1.5 Cal but after researching I found out it is synthetic, man-made food. Yuck!! Surprising it tastes fine, I could easily drink it, has a nice vanilla taste. Have been trying a new brand that actually is made from meat and vegetables but tastes gross and tastes like the metal can. He was taking 7 of the synthetic at 350 calories so now he needs 10 cans of the other to get the required nutrients.