First 283 words of the document:
CAUSES OF OBESITY
Obesity is mainly associated with the environment and certain people's lifestyles, however, scientists have now suggested
that this could also be a combination of genetics.
Identical twin studies have shown that malnutrition (in this case obesity) can be caused by a mutation of the gene leptin-this is
a gene that has been linked to the control of appetite. It is made in the adipose tissue and has several target organs such as
the brain which can suppress appetite.
The FTO gene has also been suggested with obesity, heterozygous or homologous alleles when tested were heavier.
However, obesity cannot be blamed solely on genes as only in the last 50 years obesity has risen with little or no change in
genes. Obesity has increased because of the change in the environment, e.g. the availability of fast foods.
Key word Definition
Adipose tissue This is the spare energy (extra calories) which is stored as fat
and this builds up as tissue (adipose) underneath the skin.
BMI (Body mass index A measure that most people can use to check if their weight
is healthy for their height. To work it out, it is: body
Balanced diet This contains a full range of different nutrients, in
approximately the correct proportions. The amount of
energy in the diet should be approximately equal to the
amount of energy used by the body each day.
Malnutrition This is known as bad eating and refers to the result of any
diet that is seriously unbalanced.