Enough to fill a big soup can. "That's three to five pounds of bacteria," says Lita Proctor, the program coordinator of the National Institutes of Health's Human Microbiome Project, which studies the communities of bacteria living on and in us. The bacteria cells in our body outnumber human cells 10 to 1, she says, but because they are much smaller than human cells, they account for only about 1 to 2 percent of our body mass—though they do make up about half of our body's waste.

足够装满一个大汤碗了！美国国家卫生研究进行的一项寄生菌研究项目主要研究了寄生在人体上的寄生菌落,该项目的协调员莉塔普罗克特告诉我们,"寄生在人体身上的细菌应该有3-5磅.这些细菌的数量是人体自身细胞的10倍以上,但由于细菌细胞体积比人体细胞要小得多,所以它们只占人体体积的1-2%左右,刚好是人体代谢消耗体积的一半."

The host of bacteria we carry around weren't well-cataloged until recently. In July, at North Carolina State University, the Belly Button Biodiversity study found about 1,400 different strains of bacteria living in the navels of 95 participants. Of these, 662 strains were previously unrecognized.

但是直到最近我们才将人体随身携带的细菌进行了较为全面的分类.美国北卡罗来纳州立大学在今年7月份的时候公布了肚脐生物多样性研究结果,它们在95位受试者的肚脐中发现大约有1400种不同种群的寄生菌，其中有662种是先前被未发现过的。