Blood ailments marked by excess viscosity can cause fatigue and loss of stamina, however. Thus, I recommend that he undergo an examination to clarify his blood condition. If his blood constituents are normal, his doctor will wish to search for other causes of exhaustion. On the other hand, if a blood disorder is to blame, he will require treatment. I eat a lot of eggs but don't eat the yolks.
Egg whites are nutritious and can be consumed without restriction.