The definition of calorie restriction is when the
body does not receive an adequate intake of energy.
This can result as a consequence of lack of availability
of adequate volumes of food.
However, sometimes the
failure to consume an adequate calorie intake may be a
conscious and deliberate decision, for example, in
individuals seeking to lose weight or people who suffer
with the eating disorder, anorexia nervosa. Calorie
restriction can result in malnutrition or a deficiency
of one or more nutrients.
The human body requires an adequate amount of
energy or calories to enable us to grow, perform daily
activities, produce hormones and to minimize the risk of
nutrition-related complications.
Calorie requirements
for individuals vary from one individual to the next
and are dependent on variables including gender, age,
activity levels, climate and environment and the presence
or absence ofmedical or nutritional complications.
Consequently,
it is possible that individuals of similar weight
and age may have different energy requirements owing
to unique individual needs.
In addition to the body
requiring energy to perform the aforementioned tasks,
energy is also required to support activity of the internal
organs and tomaintain body temperature. This energy is
called the basal or resting metabolism.
The basal metabolic
rate (BMR) is determined experimentally when an
individual is lying down at complete physical and mental
rest under standardized environmental conditions.
Research over many years has provided researchers
with guidelines on how to assess and determine an individuals
BMR using specific calculations.
Individuals require a certain number of calories
on a daily basis, which incidentally may vary subject to
activity levels and physical status but overall is within
a relatively stable range.
