An interesting article, entitled Cultural Differences Found in Pee, states:

Pee from more than 4,000 volunteers shows that people from different nations often have spectacularly different metabolisms. The finding could point to new ways to deal with obesity, diabetes, high blood pressure and other health problems, researchers said.

Urine samples were analyzed from some 4,630 volunteers from the United States, China, Japan and the United Kingdom. More than 1,000 different molecules were looked at. Each country turned out very different, metabolically.

“For instance, Chinese and Japanese people are almost identical genetically, which isn’t surprising, since they diverged culturally only a few thousand years ago — but they are very different metabolically,” said researcher Jeremy Nicholson, a biological chemist at Imperial College London. “We know there’s a huge difference in the diseases that different nations risk — broadly speaking, the Japanese tend to die of strokes, the Chinese of heart attacks — and we see those differences reflected in their urine,” he added. “Of course they’re different in terms of lifestyle — the Japanese tend to eat more fish than the Chinese as a whole do — but their gut bacteria are also very distinct as well.”

In the future, urine might help shed light on diabetes, atherosclerosis, obesity and even cancer. The scientists detailed their findings online April 20 in the journal Nature