I did alot of research on acid/alkaline balance some years ago, in an attempt to reduce my pain & inflammatory respose. If I eat a high acid meal (without enough balancing alkaline foods), my hip & FM pain is much more severe.
But, one does need to understand that some acidic foods can form an alkaline ash in the body which is very helpful. Lemons are near the top of the list for this alkaline ash formation. If you have arthritis or any inflammatory condition, lemons are very good for you.
Red meat is very acidic, so I try to eat it only a couple of times a week. But I DO eat read meat because I am low on lysine & red meat is one of the best sources.
An ideal diet should have 80% alkaline food & 20% acid. The important thing to remember is that when you eat meat or any other high acid food, you should eat plenty of alkaline vegetables in the same meal to balance the acid load (especially on your liver).
So for all those members, like me, who eat a high protein/low carb diet, remember to balance the acid load.
Another example is tomatoes. Raw tomatoes are not too bad at all, but cooked tomatoes are extremely acidic (hence you will see many Italian tomato recipes have a teaspoon of sugar added to correct some of the acidity).
I am in the process of preparing a list of acid/alkaline foods for my Mother who had been told to cut out all the acid foods, by her Doctor. (She should have a balance of acid/alkaline, not cut all acid foods).
But, as with all diets, you need to do some trial & testing & see what works for you.