Replacing rice with wheat is not a good idea since it means reducing your intake of amino acids (protein's building blocks) and Vitamin B. As for brown rice, it has the outer layer (husk and bran) intact thereby making it high in fibre. Now of course we want fibre but if your rice has more fibre than you can digest, brown rice will only cause indigestion. On the other hand, rice that emits blinding whiteness may not be the best source of nutrients either.