How Fast Do We Rot?

Not as fast as we used to. A friend of mine, who went to college at MIT around 1980, had a classmate who was the son of an undertaker. His dad had told him that when he (the dad) had entered the business, you had to work fast. Bodies would start to smell quickly. But now — around 1980 — that was no longer necessary. You could wait a lot longer before they smelled bad.

Which I take to mean that around 1980 the average old person, where this classmate came from, had a lot less bacteria in their body than around 1960. All that concern about “the safety of the food supply” — preservatives, yes, but also sterilization, freezing, sell-by dates, food handling rules, food safety officers, and microwave food — seems to have had an effect. From 1960 to 1980 there was a big shift from homemade food to factory-made and restaurant-made food. The uniformity of the new food caused the obesity epidemic, I believe; its sterility  caused a great increase in allergies and asthma, not to mention a bunch of other disorders.
Speaking of sell-by dates, at a Japanese grocery store recently I wanted to buy some Yakult. At check-out, it was pointed out to me that it was one day past its sell-by date. Half price. I bought two.

22 Responses to “How Fast Do We Rot?”

  1. Dennis Mangan Says:

    Maybe they didn’t have big refrigerators when the dad started undertaking.

  2. david Says:

    Presumably you could test this idea with lab animals. Their life spans are short enough that you could feed one group sterile food and another with a probiotics-rich diet. Then measure how long it takes their bodies to decompose after death.

  3. Eric Says:

    Also might have to do about the high(er) level of anti-oxidants and preservatives in our modern food. See:
    (don’t like the Super Size Me doc/movie but it shows this weird hamburger behaviour 😉

  4. Jeremy Says:

    I believe that this claim may be an urban legend. Note the source:
    “A friend of mine, who went to college at MIT around 1980, had a classmate who was the son of an undertaker.”
    See also:

  5. Aaron Blaisdell Says:

    Yup, this is one question that can not easily be addressed through self-experimentation.

  6. Smith Says:

    I just saw a Bill Nye where he said the reason we decay more slowly is the high levels of formaldehyde that we are absorbing while alive from our environment. He mentioned that there is even formaldehyde in some toothpaste.

  7. Eric Garner Says:

    If this were true there might be references to it in forensic science journals. Since state of decay is used to estimate how long someone has been dead, someone would have noticed that it takes longer nowadays. I just spent 15 min searching pubmed (hardly an exhaustive search, i know) and didn’t find any reference in forensic journals to support this. Has anyone else espoused anything other than third hand anecdotal evidence that supports whether this is even true, regardless of cause?

  8. Marsha Keeffer Says:

    The book ‘Stiff’ discusses a university that leaves corpses outside to measure the speed of decay…among other things. Fascinating, if macabre, reading.

  9. meehawl Says:

    Or maybe after decades inhaling the known carcinogenic toxin formaldehyde, the mortician had managed to fix most of his nasal sensory cells, accelerating the normal age-related loss of smell sensation. Also, habituation probably plays a big role here.

  10. Mike Dedmon Says:

    I seem to remember that Air Conditioning really became common in the late 70’s early 80’s. Before then, it was a luxury. I wonder how much that played into it?

    We take it for granted that most buildings / homes that we inhabit today have these “luxuries”.

  11. ucsd Says:

    Confirmation Bias

  12. Theo Bee Says:

    Could be all the antybiotics we take reduce our guts flora and fauna

  13. Mathias Says:

    @ Marsha: It’s for real, and its called ‘the body farm’ AKA University of Tennessee Forensic Anthropology Research Facility.

  14. Tyler Says:

    I’ve been looking for the source, and I was unable to find it, but I once read that American soldiers in Vietnam witnessed vastly different decomposition rates between Vietnamese corpses and American ones. This particular source attributed the difference to the chemicals, plastics, preservatives and other inorganic matter that now fills up so much of our “food.” Ask a vet.

  15. Bestatterweblog Says:

    Verwesen Leichen heute langsamer?…

    Leser Bernd ist im Web über einen Artikel gestolpert, der ungefähr so beginnt:”Ein Freund von mir der um 1980 das College besuchte, hatte einen Klassenkameraden, der Sohn eines Bestatters war…”
    Im weiteren Verlauf des (englischen) Textes geht es …

  16. Chuck Says:

    Can I drink Yakult after the expiration date?
    The “best if used by” date indicates that after the specified date, the number of bacteria found in Yakult will likely decrease below 8 billion per bottle. To enjoy Yakult at its premium, we strongly recommend keeping the product chilled and to discard after the expiration date.

  17. dar Says:

    It’s due to the ubiquity of Aspartame in many foods .

    The stuff turns into formaldehyde when ingested.

    [pls go to or do a search at for the details]
    -crematorium workers swear that they can tell if the dearly departed was a diet soda drinker-the burn takes that much longer

  18. Internists Says:

    2cents.. The big problem is that yakult has 80% more sugar than soda.
    For example, Coca-Cola has 10 grams of sugar per 100 grams of drink whereas Yakult has 18 grams sugar per 100 grams of drink.

  19. elaine Says:

    steer clear of aspartamine check your food labels for this additive, it is proved to be contra indicative to the human bodies normal functioning and should be banned. It is in EVERYTHING it is man made.

  20. John Lewis Says:

    Hello from Houston! I’m co-authoring a blog with my pickle circle and would like to link to your blog and a few stories if I may. And I’m not up to speed on the legal/respectful details of linking and blogging, so feel free to explain exactly how you’d like to be referenced. We’re trying to relearn what our grandparents didn’t get to teach us and you’ve done lots of good and accessible work to this end. Thanks for what you do, please keep it up!

  21. Jeff I Says:

    the human body will rot down completely to a skeleton in about a week, depending on weather conditions, temperature, humidity, etc

  22. Preserve This | Let it all hang out. Says:

    […] we die.  They make our bodies actually last longer.  Seth Roberts, a nutrition and food author of How Fast Do We Rot?, says that “preservatives in foods we eat may diminish the presence of some bacteria that […]