Although a terribly small study, let's hope it's a springboard to greater things. One other issue I have with this study is that they don't reveal how much real lemon juice is in their lemonade.
Permit me to help translate some of the medspeak:
"Citrauric" simply means the amount of citric acid in your urine.
"Nephrolithiasis" is the term for kidney stone formation. 'Nephro' means kidney, as like the medical specialty Nephrology. 'Lith' means stone. Think of 'monolith,' or a large monument carved from a single (mono) rock.
"Hypocitraturia" is a chronically low (below normal) level of citrate in your urine.
Here are excerpts from the study. The full link is found at the end.
"Purpose: Citrus fruits and juices are a known natural source of dietary citrate. Of all the citrus juices, lemon juice appears to have the highest concentration of citrate. Therefore, lemonade therapy has been proposed as a potential treatment for patients with hypocitraturia. We retrospectively evaluated the impact of long-term lemonade therapy on urinary metabolic parameters and stone formation in patients with hypocitraturic nephrolithiasis."
"Conclusions: Due to its significant citraturic effect, lemonade therapy appears to be a reasonable nn.alternative for patients with hypocitraturia who cannot tolerate first line therapy. Future study in the form of a prospective, randomized trial is needed to validate these findings."
https://www.ncbi.nlm.nih.gov/pubmed/17382731