PhDs jump to conclusions too. instead of saying they don't have enough information to make a decision or that the answer varies in a context dependent manner, they put out a blanket statement supported by a poor study.
which brings us to the next point, look up the studies they cite to back up their claims, look at the cites to those studies, etc. it usually doesn't take too long to find someone has overextrapolated or misinterpreted what was originally published. this is often done subconciously as we all have our own biases and they do influence such things greatly.
another glaring red flag if you will is the complete lack of coverage of any newer studies where they may actually be able to take measurements that investigate such audacious claims.
in short, unless you are suffering kidney failure or have a very rare genetic disorder, you will find that your body - and kidneys in particular - can handle much more protein and amino acids than you think.
elevated levels of breakdown products also indicates that your whole body protein turnover is higher than normal. this includes all the proteins inside each cell which are the machinery that operates your cells as well as muscle tissue. this means you are rebuilding your body from the inside out at a faster rate. something most people want and need.
i can also tell you for a fact that one of the most prominent researchers in the field in favour of moderate to low protein intake has been funded in large part by the parent of gatorade as well as a company with large interests in soy protein.
now instead of going off on this and claiming it is a scam to get more soy on the market, i think there may be an explanation that leaves no villans:
the discussion on protein need, because this is really what we are talking about. and this is a bullshit discussion. why? simply put, there are many viewpoints from which you can look at the problem.
government/heathcare view point
this value will be equal to the minimum amount required so you don't die or get sick. this is around 60g for an adult male and 70g for a pregnant or lactating woman. oddly enough, this is just below the average amount of protein consumed per person in canada (around 75g) - obviously the oddly bit was sarcasm. this is also around what many scientists who are focused on protein 'need' recommend. that's right, you only need so much and if you take more you will die! quite frankly i think they even make religious fundamentalists look bad here with such zealotry.
maximize effect of protein intake view
here we will see recommendations on the order of 1g/lb LBM to twice that, once again activity dependent. lets say you run or play a sport a couple hours a week and workout a couple hours, then the low end will suffice. the high end is for elite athletes training with volumes many times more and is part of a diet that has more fat and carbs to the point were the percentage of protein is actually lower than the active person since they need the extra energy to rebuild the much greater damage done.
now most view points will be one of these two with a little variation due to some asinine dogma or belief, usually neither will totally be correct. at this point i would say it is pointless to continue the arguement with the low protein side because they will never grasp this. rather i suggest people look at what hunter gatherer peoples tend to eat.
you will find that the average protein intake is around 3 times what ours is (society at large, not T-Nation types). and this is modern day groups who live on marginal lands food availability-wise. they also eat lots of fat, usually of a good balance, and lots of veggies and fruit, so high fiber, but not grains based. rates of cancer, heart disease, and other western lifestyle-related (read shit food intake and sitting on your ass) disease is low.
in conclusion, not only is more protein and BCAA not detrimental to healthy individuals, within reason, it is actually likely to improve your health. if you are not using steroids, your body is going to have real hard time putting on lean mass if you are not paying attention to your health.
so next time you are presented with such assertions, ask if they can conclusively show that the research was not funded by a sports drink manufacturer selling 10 cents worth of stuff for the price an amino acid drink or a protein-carb blend like Surge may set you back. also, ask if they bothered to review any recent literature supporting protein/BCAA and why it is incorrect because results from people with kidney disease do not apply.