Hello and thanks for researching this very important question!

Tortoises (as all animals) grow according to genetically defined limits.

The shell grows together with the body at a pre-determined rate, assuming the animal eats a nutritionally and calorically complete diet. The shell grows as a result of the body's metabolism of nutrients...food is processed by the body, then is forwarded to the shell-producing cells at the proper rate.

If the body is not fed properly, the shell cannot grow properly and will be deformed and fragile. In this way, the body can be viewed as the limiting factor, but starvation conditions do not describe the optimum or usual conditions found in nature.

Tortoises can become overweight in terms of the body...they can become "fat" and subsequently unable to withdraw completely into their shells.

In this way, one can view the shell as a limiting factor as far as "growth" is concerned, but overweightness is strictly-speaking not a natural condition. Fat can continue to pile up on the frame of the body, even though the bones, internal organs, muscles and shell have stopped Growing.

Each species of tortoise has special nutritional needs...foods such as would be found by the animal in nature should be given in appropriate amounts and at the right times of year. Captive reptiles do require certain vitamin and mineral supplements to remain healthy.

If you need help locating reliable feeding information for your pet, please Reply with the species you are caring for.

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