Urine composition varies with geographical location

Apr 22, 2008 18:06 GMT  ·  By

As expected, urine differs in composition depending on what you eat or drink (that without even mentioning the way in which alcohol and coffee impact on it). Moreover, a new research carried out by a team led by Elaine Holmes, Professor of Chemical Biology at the Imperial College London (ICL) and published in the journal Nature, made a "urine map" that could tell where a person comes from based on urine analyses.

The team investigated frozen urine samples from 4,630 people, collected between 1997 and 1999 in China, Japan, the UK and the U.S. Besides revealing different types of human metabolism and diets in different geographical places, the research also found new methods of detecting potential health issues, like obesity, diabetes or high blood pressure, based on the urine analysis and its assigning to an ethnic group.

"What our study really shows is how incredibly metabolically diverse people are around the world. British and American [metabolomes] are nearly identical. Japanese and Chinese people are totally different metabolically even though they are nearly identical genetically. People who lived in Hawaii had metabolomes equally similar to those of people on the mainland United States and in Japan," said co-author Professor Jeremy Nicholson, Chair In Biological Chemistry at ICL.

Some of results though were quite unexpected.

"The biggest difference between the 17 groups was between people from South China and everyone else. They have a very different and much broader range of diet. Very broadly speaking, the southern Chinese are the healthiest and the people in southern Texas are least healthy," said Nicholson. He pointed that the human wastes are very specific related to the ethnicity of the person.

"We know there's a huge difference in the diseases that different nations risk: the Japanese tend to die of strokes, the Chinese of heart attacks -- and we see those differences reflected in their urine. 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," Nicholson told LiveScience.

"'In your guts, you have about 1.5 kilograms (3.3 pounds) of 1,000 different species of bacteria. If you include all the genes from bacteria along with your own, only about 1 to 2% of the genes in your body are human, with the rest from the gut microbes. And what bacteria you have can be quite different from person to person," he added.