Many pet birds require grit to help with healthy digestion. A bird’s stomach is made up of two parts. Firstly, there is the glandular stomach where whole grains are pre-digested with enzymes then a muscular stomach or gizzard where the pre-digested food is ground up. The tiny stones in the grit that your bird swallows act like mill stones and turn the food into fine, digestible particles. If birds do not have grit, they can have difficulty digesting food. Why is grit important for birds? Grit is made up of small, angular stones that are required to break down seeds in a bird’s stomach and allow it to digest in a natural way. Grit is excreted as part of normal digestion, so bird need a constant supply of grit. Shell limestone (oyster shell) provides calcium, which birds need for healthy bones and strong eggshells.Charcoal (activated charcoal) absorbs toxins, helps to regulate stomach acid and aids digestion.