The Biological Explanation of Anorexia

Genetic Explanation 

We inherit our genes from our parents, so if disorders are genetically inherited and our parents have a genetic predisposition to a disorder like anorexia nervosa, we are more likely to receive similar genes, giving us a high chance of getting the disorder.  Strober and Humphrey (1987) found that relatives of eating disorder patients were between four and five times more like than members of the general population to develop an eating disorder themselves.

There have been twin studies carried out between monozygotic twins (MZ) and dizygotic twins (DZ) on Anorexia. MZ twins, or identical twins, have exactly the same genes, whereas DZ twins, or non-identical twins, share only 50% of their genetic material. If Anorexia is wholly genetic, that means that if one MZ twin develops the disorder, the other twin will definitely develop the disorder at some point in their lives, and if one DZ twin develops anorexia, the other twin has a 50% chance of developing the disorder too. If the environment and genes play a role in developing anorexia, then if one MZ twin develops the disorder, the other twin has less than 100% chance of developing it, due to the environment they are living in. Holland et al (1984) found that 56% of MZ twins had anorexia and 5% of DZ twins had anorexia. Kortegaard et al (2001) found that 25% of MZ twins had anorexia and 13% of DZ twins had anorexia.

Evaluation of the Biological explanation of Anorexia;

Strengths;

• The person suffering from anorexia is not seen as being responsible for their behaviour and is seen as a victim of the disorder of which they have little or no control. This removes issues of blames and labelling the person.
• Research does prove that anorexia does have at least a degree of biological basis. Genetic abnormalities have been found using scientific methods which have been tested for reliability.

Weaknesses;

• it is argued that twin studies assume twins have an identical environment and this may not be the case.
• MZ twins are not totally identical (fingerprints).
• There is not a 100% chance of MZ twins developing anorexia if the other one has it; this means that the environment must also play a role
• The genetic explanation is not helpful in seeking a treatment for someone suffering from anorexia.

By Zoë Evans