National Geographic
Menu

Growing Teeth and Four More Odd Uses for Urine

For those who’ve lost their teeth to accidents and decay, there may be a new way to restore your pearly whites: urine.  

Scientists in China have successfully used cells found in human urine to regrow teeth. If that’s not enough of an ick factor, the scientists grew the teeth in mouse kidneys.

urine clock picture
Hirenbhai Bheda displays a wall clock that runs on cow urine in Luni, India, on June 5. Photograph by Sam Panthaky/AFP/Getty Images

The researchers, led by Duanqing Pei at the Chinese Academy of Sciences in Guangzhou, converted cells collected from urine into what’s called pluripotent stem cells, which can become any kind of cell in the body. These stem cells were then mixed with dental tissue from mouse embryos and implanted into mouse kidneys. (Read more about stem cells.)

The entire process took just a few weeks: several days to incubate the stem cells, and then three weeks to grow them in the kidneys, according to the study, published July 30 in the journal Cell Regeneration.

These were not, however, normal teeth. They were probably even less useful than George Washington’s mythical wooden dentures, given that the teeth were soft and misshapen and not actually, you know, attached to a person’s jaw.

In an interview with the BBC, University College London stem cell biologist Chris Mason said urine “is probably one of the worst sources [for teeth]—there are very few cells in the first place and the efficiency of turning them into stem cells is very low.” (Explore a human-body interactive.)

And for the teeth to work, they’d have to be integrated into the gum’s “pulp” of nerves and blood vessels, which would be a “big challenge,” Mason said.

Though human urine hasn’t yet unemployed the tooth fairy, other researchers have come up with some surprising and creative ways to reuse the liters of liquid gold each of us create every day.

Urine as Fuel

At the 2012 Maker Faire for innovators in Lagos, Nigeria, a group of three schoolgirls created a backup generator that could run on human urine. The device uses an electrolytic cell to break down the molecules found in urine and extract pure hydrogen. (Also see “Urine Battery Turns Pee Into Power.”)

The hydrogen is passed through a cylinder of borax to remove any moisture, and then delivered to the generator. The girls used one-way valves to reduce any explosion risks from the hydrogen. One liter of urine can produce up to six hours of electricity.

Other scientists from the Bristol Robotics Laboratory have also been investigating urine fuel cells, only they used microbes to break down the molecules in urine and produce the electricity.

Urine as Medication

Peeing into a cup generally yields a diagnosis, not a pharmaceutical. But when researchers analyzed the urine of menopausal women, they realized they could extract an important—and potentially lucrative—medication for infertility.

As a woman approaches menopause, her ovaries start to become deaf to the monthly siren calls of hormones. The pituitary gland responds by secreting even more hormones, such as follicle-stimulating hormone and luteinizing hormone, which stimulate eggs to mature in the ovary.

Levels of these hormones are often low in infertile women, which gave scientists the brilliant idea to gather urine from perimenopausal women to extract and purify the precious hormones. Thus was born the infertility drugs Menopur and Pergonal.

Urine as Compost

When researchers combined compost with human urine, they found they had created a fertilizer that is superior to compost alone. The trick appears to be the extra nitrogen from the urine, which helps to boost plants’ growth.

Although it isn’t as powerful as commercial fertilizers, urine is freely available and a potentially more cost-effective and environmentally friendly fertilizer. (Related: “Human Pee Added to Compost Boosts Crops.”)

Urine as Water

People have been drinking urine for millennia, often for health reasons. But NASA has developed a new filtration system to turn human wastewater like sweat and urine into potable drinking water. The Forward Osmosis Bag (FOB) was designed to give astronauts an extra source of drinking water in space. The FOB, however, can be used outside of zero gravity and, if the technology is scaled up, may help create additional drinking water around the globe.

These ideas are not, of course, the only ways urine can be used—people are inventing new things every day. Even my cat has gotten in on the game, creating inventive works of art on my rug after an inadvertent change of kitty litter brands.

What ideas do you have for using urine?

Comments

  1. dr.harshal patil
    maharashtra, INDIA
    June 30, 12:06 am

    Human urine
    In Ayurvedic system of medicine its called Swambu chikitsa.
    for details refer indian system of medicine.

  2. Bono Lou
    United States
    April 27, 12:20 pm

    as a young girl I often had a rake. My grandmother would have my pee in a cup and she would drop with a cotton ball while it was warm drops of urine and my ear with a cotton ball and have me lay down and my ear ache would go away and minutes. It was disgusting but the pain and the results were worth it.

  3. stephen dias
    D.Paula
    February 8, 7:53 am

    Dear Sir,

    I agree with you that Urine does lost of miracles but very few people make use of it. There was one great politician in early years was drinking urine and he could probably survive for more than 90 years. What this gentlemen say that his granny was carrying and growing some plants from her urine i agree totally because I myself do at the age of 65 years and my plant is growing well an giving fruits also ,better than my neighbor place of the same kind of tree and gown at the same time. Whereas her tree does not give anything since they do not feed this tree with their urine. One thing for certain that many ailments projected by this author or gentleman may not be correct. I am not sure whether this man drink urine , and if it so why his eye sight is not corrected with urine. He uses spectacles below his eye since his vision is bad. That means Urine has not given him that much power.( if he drinks his own urine only).

    Stephen Dias

  4. Alex mugwira
    kiambu kenya
    January 14, 2:13 pm

    woow!iam suprised to learn dat something dat seemed disgusting can turn to gold!

  5. Andrew Israel Kazibwe
    Kigali
    September 16, 2013, 5:36 am

    Am inspired,I’ll start right away with therapy

  6. Dominic Dominion-paul
    Aba,Nigeria.
    August 9, 2013, 6:49 am

    Urine and Zobo(look for zobo botname cures toothache and can help you manage broken infected tooth again like molars by killing the infection and growing the teeth at the base for use.Urine is good for regrowing baldhead of new hairs.Urine is good.

  7. Carl Torres
    August 8, 2013, 11:49 pm

    Teeth whitening kits have the ingredients “urea” and “uric acid”. Romans used urine to whiten teeth. Coincidence?

  8. Carl Torres
    Tulsa, OK
    August 8, 2013, 11:47 pm

    Romans used urine to whiten their teeth… and if your read the ingredients carefully in teeth whitening kits, you’ll see “urea” and uric acid…

  9. Carl Torres
    August 8, 2013, 11:46 pm

    Romans used urine to whiten their teeth…

  10. Yandy Reyes
    NYC
    August 7, 2013, 5:07 am

    The only reason this sounds digusting to some ppl is because we have been conditioned to this our waste is so nasty. If we grew up thinking of it as usable and useful, it would not be wasted and would even be sold in markets (if widespread enough). So come one ppl, please be a little open-minded of the possible benefits involved.

  11. Christine Dell'Amore
    United States
    August 6, 2013, 11:42 am

    These are some interesting ideas—has anyone actually tested any of them?

  12. MVULASATIEL
    ZAMBIA
    August 6, 2013, 4:14 am

    urine has proved to working even when one has fits ,by a mixture of traditional herbs .

  13. Monica Walker
    Durban, South Africa
    August 6, 2013, 3:19 am

    Of course you all know how soothing it is on blue bottle and jelly fish stings …

  14. Wendy
    Singapore
    August 5, 2013, 10:27 pm

    I used urine for Hyroid & jellyfish’s sting if no other alternative like Vinegar is available. In fact, it can be used for most sting that I encountered.

  15. bryan joyce
    western australia
    August 5, 2013, 2:38 am

    whist in the army patrolling the jungle,at the end of the day we took our boot and socks off urinated on our feet and when they dried put boots back on. never suffered from tinea

  16. mostafa abdel raheem
    cairo , egypt
    August 3, 2013, 10:50 am

    Arabs were using urine from ancient times and has many uses, especially camel urine

  17. steve sinclair
    Fort McMurray, Alberta, Canada
    August 2, 2013, 2:45 pm

    Urine can neutralize jellyfish stings

  18. Thomas Vogler
    Germany
    August 2, 2013, 4:18 am

    Flush it down the Toilet. This article is disgusting.

  19. Rodney
    Johannesburg, South Africa
    August 2, 2013, 1:51 am

    Urine can also cure purples Pimples if u urine on your hand & wash your face with it!!!

  20. Cosmin
    August 2, 2013, 1:24 am

    Yellow snow drawings and ice cream.

  21. Ivonne
    August 1, 2013, 7:43 pm

    Try cleaning your house? Mop your floors with urine.. I heard it leave the, shiny!!!

  22. Joe Herman
    Israel
    August 1, 2013, 11:39 am

    Try urinating on athlete’s foot. Urine kills that kind and similar kinds of fungus.

  23. Sal Tomy
    Israel
    August 1, 2013, 10:47 am

    Urine can be used to cure eye infection.

  24. Tom Key
    California USA
    July 31, 2013, 6:29 pm

    Hair conditioner. Tribespeople living in arid regions from the Altiplano of Sur America to Tibet and Saudia Arabia have long used urine to wash out their hair. Makes it shiny and gets the dust and dirt out.