Possible Clues:

• You wouldn't have a smooth time with this part of your diet
• Good for the diet, but bad for those who live in it
• Not a smooth time to keep one moving
• Seems you won't have a calm time with this, but it's good for you, of course
• Indigestible material to stimulate intenstines
• It won't give you an easy time, but it's best to swallow it
• Not an easy time for food like this
• Fibre, maybe, a suspect detail?
• Not a smooth time for food
• Healthy fare served up by crone in make-up