One advantage of animal trials is that they allow one to study a greater variety
of nutritional interventions than is possible in human studies.
They also allow
for diverse interventions, some of which are impossible to perform in humans.
Further advantages come from the possibility of investigating putative mechanisms
of nutritional programming and identifying the precise developmental windows in
which early nutritional imbalances contribute to later disease. Also, lifetime studies
can be done. The major limitation is that the results of animal studies cannot be
extrapolated to humans. In addition, the clinical contribution of animal research is
being questioned. Recently, it was stated that much of animal research into potential treatments for humans is wasted, because it is poorly conducted and not evaluated through systematic reviews [3, 4].