BETHESDA, Md., March 28 (UPI) -- If identical twins eat the same things and exercise the same way, they should have the same weight, but U.S. researchers say they may not.
National Institutes of Health investigators Carson Chow and Kevin Hall find that identical twins with identical lifestyles can have different body weights and different amounts of body fat.
The study, published in the journal PLoS Computational Biology, uses a branch of mathematical systems theory -- dynamical systems theory -- to demonstrate that there can be an infinite number of body weight solutions, even if the food intake and energy expenditure rates are identical.
However, the researchers also show that another class of mathematical models directly refutes this, predicting that food intake and energy expenditure rates uniquely determine body weight.
The existing data are insufficient to tell which model is closer to reality, the researchers said.
