In some cases a lack of hormones may lead to shrinkage of the organ, for example, with breast shrinkage after menopause. A reduced blood supply can starve the tissue of essential nutrients and oxygen.
If nerves are damaged, there are no signals from the brain or spinal cord to activate the tissue (e.g. muscles) so they gradually shrink. In paraplegics there is no nerve stimulation to muscles below the level of the spinal damage, so the muscles shrink and waste away.
Generalised wasting may be due to a number of diseases including:
- diabetes mellitus;
- thyrotoxicosis (increased thyroid hormone in blood);
- Addison’s disease (inadequate hormones produced by adrenal glands);
- phaeochromocytoma (adrenal gland tumour);
- occult carcinoma (cancer of unknown origin);
- hypopituitarism (inadequate hormones produced by pituitary gland);
- anorexia nervosa,
- some fad diets.