SORU: aşağıdaki parçaya göre cevaplayınız
According to the passage, the theory that obesity has a strong genetic basis ----.
For years, it has been assumed that obesity is the
result of "too much food and too little exercise".
While this maxim is largely correct, the etiology of
obesity can be much more complex. There is a
well-documented familial tendency, but whether
this is of environmental or genetic origin is
unclear. Studies of twins separated at birth and
living apart provide strong evidence for a
substantial genetic influence. Children of
overweight parents, when adopted by "lean"
families, have a greater tendency to become
obese than do adoptees from non-obese natural
parents. "Energy efficiency" may contribute to
obesity; with reserves of fat deposits readily
available to metabolize in the obese, a given
amount of activity requires a smaller expenditure
of energy. This theory has been invoked by those
who complain that they "gain weight whether they
eat or not", and indeed there is evidence of
differences in energy efficiency among
individuals. Similarly, obesity has been attributed
to abnormally low basal metabolic rates (BMRs)
since obese individuals do show lower BMRs.
However, this fact is due to an artifact of BMR
measurement; a larger proportion of the total fat
mass of an obese person is inert, lowmetabolizing
fat, a fact that makes BMR
calculations lower.