> That process happens in the liver and the older you are the slower the urea cycle.

Not exactly. As I said earlier, renal function degrades slowly in old age. But that has no bearing on the pink slime issue, because normal nitrogen clearance capacity is orders of magnitude greater than dietary ammonia consumption, even in the elderly.

> While an athlete may be able to handle additional pink meat I would question why a high performing athlete would.

No, nitrogen clearance has nothing to do with athleticism or fitness level. All healthy adults can handle high protein diets. Old, young, fit or not; if you don't have impaired renal function or some kind of genetic metabolic disorder, your body can and does safely process hundreds or thousands of times more ammonia than what you eat in your food.

> The trace amounts you speak of are the maximum amounts before the taste starts to change.

No, those are food safety limits set by the FDA. [EDIT: nope, actually those are just some random tested ammonia levels. As a GRAS additive, the FDA actually doesn't directly limit ammonia content of foods or cosmetics. That's how safe it is.]

Look, I'm not telling you to eat pink slime. I certainly won't eat it. But it appears that your opinions are fixed in defiance of logic or evidence. I really think you'd be better off with some more basic knowledge, and maybe a little more willingness to learn.

You are making the case that eating pink slime and consuming ammonia is safe and a welcome thing because the FDA doesn't test for ammonia in food. You are also saying that our ability to detoxify doesn't change with age or fitness level.

Each message you try to put down the other person to change the discussion into a personality based discussion. Personal attacks are a sign of weakness in your position. Using personality doesn't make your position stronger. You'll labeled yourself as an open minded non-meat eating person educated in FDA testing and human anatomy. That's a great profile but let's get back to the facts.

You are arguing that ammonia in food at any level is okay and wouldn't put additional stress on the detoxification process because the fda doesn't test for this?

The FDA does test this in 1974. Ammonium hydroxide has been tested. They have deemed it safe at normal food levels because it is part of the normal human process. That position while technically correct doesn't take into account all of the other stresses including age as factors that slow down these processes. What do you think would happen if you went on a 30 day pink meat challenge?

I'm sorry, I really don't mean to put you down. I'm pointing out that the things you're saying make absolutely no sense. You seem to have no idea what you're talking about, and you seem to have no desire to learn more. Honestly, I feel like I'm talking to a child. Or a bot.

Try reading this out loud, see if it helps: every human body is an ammonia factory, and easily handles thousands of times more ammonia than what is present in foods. The amounts of ammonia found in foods is completely insignificant compared to the ammonia your body naturally produces. If you have a condition that impairs your ability to excrete nitrogen, the only way to lower your blood ammonia level (and urea) is to EAT LESS PROTEIN. Avoiding ammonia has no significant effect. Read all that again to help get it into your brain. And if you don't believe me, just look it up. This isn't difficult stuff; it's basic, basic physiology.

Just for fun, and at the risk of repeating myself:

> You are making the case that eating pink slime and consuming ammonia is safe and a welcome thing because the FDA doesn't test for ammonia in food.

No, not because the FDA says so. Rather, I've explained some basic physiology to you, and provided numbers showing that dietary ammonia has an insignificant effect on the human body. Your body produces hundreds or thousands of times more ammonia than you eat from scary pink slime, every day. You don't have to take my word for it. Go read about it. You'll probably enjoy it.

> You are also saying that our ability to detoxify doesn't change with age or fitness level.

That's half correct. Renal function declines very slowly after middle age in healthy people. I've seen no evidence that hepatic urea production declines with age, nor have I seen evidence that fitness level affects nitrogen conversion or clearance. If you have any evidence to support your opinions, I'd love to see it.

> You are arguing that ammonia in food at any level is okay and wouldn't put additional stress on the detoxification process because the fda doesn't test for this?

No, see my answer above. Or just re-read my earlier comments. The FDA's testing is incidental.

> That position while technically correct doesn't take into account all of the other stresses including age as factors that slow down these processes.

No, age is accounted for investigations of this stuff, because age is part of the standard formula for eGFR, which is a measure of renal efficiency. But that doesn't matter, because if there are any "factors" that impair your ability to excrete nitrogen, then the only thing that will help is to lower your protein consumption, which is where the vast majority of the nitrogen comes from. Any ammonia in food will not have a significant effect.

> What do you think would happen if you went on a 30 day pink meat challenge?

You mean pink slime? Well, try running the numbers! I've given you all the information you need to find the data and work with it, but I'll make it super easy for you. Let's use these assumptions:

1. Let's say you eat a big 10 ounce patty of pink slime every day.

2. Let's say that pink slime contains 400 ppm ammonia, which is at the high end of tested values.

3. Let's use a dietary nitrogen content conversion factor of 16%, which is the standard for meat protein. If you need more info, go read about "Jones factors". It's easy stuff!

Now, you'll need to figure out both the total ammonia content and the total protein content of your pink slime. The ammonia is easy, given assumption 2 above. You can look up the protein content on the internet. Here's a hint: the USDA categorizes pink slime as 18/15 lean ground beef, so you can use the nutrition data for that product in any of the USDA databases.

Convert the ammonia and the protein to equivalent nitrogen content. Use the standard 16% jones factor for the protein.

Now, you'll be able to tell me how much extra ammonia you'd get from the pink slime, versus, for example, a serving of "normal" ground beef with half as much ammonia. Give it a try.

And then, when you have thah number, reflect once again on the fact that it doesn't matter. If you need to lower the ammonia (or urea, more likely) in your blood, eating ground beef instead of pink slime will do you no good. Even if you're old and sick, the ammonia you make from ALL of the protein you eat completely overwhelms all other sources.

Seriously, give those numbers a try. Let me know how it goes.