If your iguana is showing signs of NSHP or MBD you must bring your pet to a veterinarian. Your iguana is suffering from Nutritional Secondary Hyperparathyrodism or a metabolic bone disease.
It doesn’t mean that your iguana is unhealthy if it is oversized or fat. Proper diet must be given. Provide your iguana with a high calcium and low phosphorus diet. Also, always make sure that your pet gets a proper sunlight.
If you’re iguana body seem to be bony and fat and jaws seem to be swollen, your iguana is in the critical stage of NHSP or MBD. This would lead to brittle bones that cause deformities and fractures.
To avoid this to happen give your iguana proper diet, exercise and should maintain a good weight but not becoming overweight. It is also necessary for a fat iguana to obtain the needed calcium or phosphorus ratio for a healthy bone.