Any risks associated with excess protein consumption?

To my knowledge, no healthy person has every been harmed by high protein intake.

[NOTE: If you have pre-existing kidney disease or are at high risk for renal disease, you may have to moderate your protein intake. If this is the case, talk to your doctor about what dietary action you can take and if in any doubt see a kidney/renal specialist.]

I'm quite sure if there ever had been a confirmed report of high protein intake causing any harmful health effects that I would have heard about it. You see, some people in the nutrition community note that general protein recommendations are set at 15-20% of dietary intake and less than 1 gram of protein per kilo of bodyweight. So when they hear about much higher recommendations, they become concerned.

What they don't appreciate is that, as prominent protein researchers have pointed out (including one of the researchers who provided much of the scientific data upon which protein recommendations are made), this level has been set as a "minimum" amount required to avoid muscle loss in the majority of the population. These recommendations are not based upon the optimum amount of protein intake for health and exercise recovery, optimum immunity, bone density, etc...

So there is no need to be concerned with protein intake having an adverse effect on your health. On the contrary, I would be concerned if you were only getting the amount of protein recommended in the general recommendations!

The only major consideration when on a high-protein diet is that you should eat lots of a variety of vegetables and ensure you get an adequate calcium intake (which you should obviously be doing anyhow). This will ensure that the somewhat acidic effects of a high-protein diet won't cause calcium loss from bone. Studies show that if you get adequate calcium intake, higher protein intake is associated with increased bone density and strength.