What Gorilla Poop Reveals About Our Own Lousy Diets

By Gemma Tarlach | May 3, 2018 4:05 pm
CAPTION (Credit Wikimedia Commons/Ltshears)

While this captive gorilla noshes on fibrous veg such as kale, in the wild, the animals’ diets vary seasonally, as does their microbiome. (Credit Wikimedia Commons/Ltshears)

Researchers analyzing the gut microbes of gorillas and other primates found seasonal shifts that underscore just how much is missing from the modern human diet — and why it matters.

Right now, you’re hosting your own special ecosystem. Millions of microbes live out their lives on your skin and in every nook and cranny, especially in your gut, where they perform a multitude of essential tasks. Sort of like tiny houseguests who actually cook and clean. The microbiome — particularly the mini-cities in your gut — has been a popular research focus of late as scientists investigate what it can tell us about health, behavior and even human evolution.

Researchers probing the poop of 87 wild western lowland gorillas in the Republic of Congo over three years found that the apes’ gut microbiome population fluctuated seasonally based on resource availability. Though the animals’ diet typically consisted of leaves and bark, in the dry season they chowed down on abundant fruit, and their microbiomes changed accordingly.

A similar seasonal shift has been observed previously in our own species, in members of traditional hunter-gatherer societies, such as the Hadza of Tanzania. It’s not the case, however, for the average human living in an industrialized environment where a global industry serves up the same produce year-round to restaurants and grocery store shelves, whether it’s snowing or sweltering in your neck of the woods.

The researchers sequenced the genetic material of the different microbes present in the gorillas’ fecal material to find that the seasonally-shifting bacterial populations did different things.

Bacteria that helped the apes break down bark and other fibrous material were replaced annually by different microbes when fruit was in season: These fruity fellows fed on a protective layer of mucus in the gut itself. In turn, the arrival of bark season (mmm!) sent the mucus-nibblers packing and brought back the bacterial breakdown team.

Given how close Homo sapiens are on the Tree of Life to gorillas and other primates included in the study, it’s not crazy to compare gut microbiomes and see that ours may be falling short in terms of optimal health. The average human in an industrialized society with a season-less diet — especially one that favors animal protein over veggies — is likely living a fiber-deficient life and has the unbalanced microbiome to prove it.

With our microbiomes already less diverse than those of our nearest primate kin, the lack of seasonal fluctuation may mean the ever-present mucus-eaters and other potentially harmful bacteria in the gut can nibble away at us year-round, increasing intestinal inflammation and even potentially raising the risk of colon cancer and other disease.

The research appears in Nature Communications and is open access, so take a read for yourself.

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  • Erik Bosma

    Turns out that serotonin is also produced in the gut. No wonder having bowel disease is so depressing.

  • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

    Have a glass of kefir with lunch each day. Bare floors or wall-to-wall carpeting is your choice to make. Also note that intestinal worms are wonderfully immunomodulating. Porcine whipworm damps Crohn’s disease and “irritable bowel syndrome” without risking death from brain fungus. One wonders about the sudden blooming of celiac disease in Baby Boomers. Gluten Free! is the new portable water bottle.

    Patient, “Let’s try porcine whipworm.”
    Doctor, “But ti doesn’t cost $1000/month in pills and three times that for side effects and ‘monitoring’!”

  • John Thompson

    “Though the animals’ diet typically consisted of leaves and bark”
    Two observations about that:
    1. It’s been an exceptionally long time since humans could process leaves or bark. Many herbivores can’t even process those things.
    2. If it were such a great diet, then they would have been doing great in North Korea during the last food shortage.
    As far as seasonal bacteria in the gut – the bacteria is always related to what you eat. So if you eat different things seasonally, you will feed particular types of bacteria more or less. Many people are familiar with how people can have a harder time digesting milk as they age, and that’s entirely due to the fact that when they were young they consumed lots of milk, which meant a large amount of bacteria that fed on milk. As they got older they consumed it less often, so the bacteria that could help break it down diminished in number. That adult tries an occasional glass of milk and has problems, but an adult who consumes it regularly and consistently does not.
    If the particular bacteria themselves were so beneficial, then we would just give people the bacteria. But without the supporting food, the bacteria wouldn’t do much.
    We generally have the bacteria for the food we eat.
    Often people seem to forget that evolution is constant, and that those ill suited to the new diet SHOULD have problems and hopefully they will not reproduce and cause more people tho have the problems, but if they do then evolutionary theory is they should have their genes marginalized (or even disappear in time).
    Unfortunately we work to prop up failed genetics – and the general result is devolution of the species.
    There are people today who are allergic to mother’s milk or sunlight – and we help them to live “normal” lives, including reproduction – but clearly we do that in defiance of evolution and the natural selection process – resulting in what some would call devolution.

    • Maia

      DO What? Humans eat lots of leaves and many very fibrous things such as roots, stalks, fruits with skin, nuts, legumes, seeds… although not much bark, I agree.

      • John Thompson

        Most leaves cannot be eaten.
        Plants don’t actually want us eating their leaves – nor any other creatures.
        So leaves often contain toxins for that exact reason.
        The few varieties of plant leaves that we could eat have become the varieties we harvested and replanted – selecting them until we get the vegetables we have in stores today.
        I should have been more clear that we cannot eat the vast majority of leaves.
        You can’t just go into a forest and start picking off leaves to eat.
        And for that matter many herbivores cannot do that.

        • nik

          ”You can’t just go into a forest and start picking off leaves to eat. ”

          Mainly because modern man has lost the knowledge of what leaves are edible, and what are not.
          However, a good guide would be to watch what monkeys eat, and then eat those, this is part of old survival instructions to military airmen who may be unfortunate enough to crash into tropical forest.

          • John Thompson

            You can eat SOME leaves.
            I’ll grant that.
            But not MOST leaves.

          • nik

            Actually very few leaves cannot be eaten.
            Many have minimal nutrition, so are not worth eating.
            Some are an ”acquired taste” and may not appeal.
            As a country kid, I used to chew all sorts of plants, Even the succulent bases of grass stems can be chewed, for the juices, but not the green parts. Most fruit tree leaves are also edible.
            Hawthorn, leaves were another, and the fruits in the autumn. Dandelions make good salads for those that like a slightly bitter taste.
            Elder flowers and berries are edible, as are many other flowers.
            Also there are loads of fungi that fruit at various times of the year, but knowing which are edible is VERY important! Those like ‘Death Cap’ are not named for their edibility.
            There are many hedgerow plants that can be eaten, and waterside plants too, but again, there are a few that will kill you, like hemlock, but are easy to recognise. Water cress, and bulrushes are well known edibles.
            Trees like Birch and Maple have edible sap, high in sugars, so good for energy.
            Cinnamon bark is also very good to chew, in small quantities for its benefits for the nervous system.
            Survival programs on youtube list and explain quite a few plants, if you’re curious.

          • John Thompson

            You focus on the ones you can eat – but there are many more you cannot eat.
            Again, plants don’t actually want their leaves eaten.
            I don’t doubt that of the hundreds of thousands of species of plants that you can eat thousands of them.
            But where were the societies of people who just ate leaves they found?
            Berries, nuts – meat – HUNTER/gatherers.
            From there we went to farming.
            We didn’t farm every plant we could consume for good reasons.

          • Maia

            If you read the research, the majority of day-to-day calories that hunter/gatherers ate, came from plants…this mixture, with a preponderance of plant foods is arguably still the basis of the healthiest diet today.
            But John, you are creating an unnecessary and artificial choice: we don’t have to eat zero leaves or all leaves! We can eat leaves and eat other things, too.

          • John Thompson

            You tried to shift it from “leaves” to “plants”.
            I mentioned berries and nuts.

          • Maia

            Who ever said that we should live like gorillas? They were critical of “on demand” berries flown in from thousands of miles away, eg, or eating very few varieties, too much meat and dairy, etc.

          • nik

            Farmers grow, what is easy to grow, and what is the most profitable.
            There are many edible leaf plants that are nutritious, and tasty, but are difficult or expensive to farm, or harvest. Many are also ‘not preferred’ by the public, so cant be grown in sufficient quantities to be profitable. Some have a poor ‘shelf life’ so may be spoiled by the time they can be served to the customer.
            ”Hunter-gatherer” is a modern term, ”forager” would be more accurate. In other words, people ate whatever they could find and consume, and plants were abundant, and easy to ‘catch.’
            Animals were harder to find, and even harder to catch, so plants formed the main part of the diet, and meat was relatively scarce.
            I’m now living in France, in a ”Parc Naturel” and I’m finding lots of plants that are edible, but you will never see in a supermarket, or even the weekly village market.
            Modern mans diet is severely deficient in nutrients, compared to those past, as each plant tends to synthesis its own range of nutrients, and when they are no longer eaten, that particular combination of nutrients vanishes from the general diet.many peoples health problems can be traced to dietary deficiencies.
            Thats why health shops are booming, selling supplements of elements that have disappeared from the general diet.
            One historical example was, iodine, which was abundantly available to the early peoples that lived on the coastal planes, from shellfish, but absent from the diet of people who lived far from the coast, in the days when cars were scarce.
            The US government had iodine put into salt, to stop the population from suffering thyroid problems from iodine deficiency.

        • Maia

          There are many more edible leaves than those commonly grown as crops or ones you see in grocery stores. Many are called herbs or weeds and are very high in nutrition. If you know your plants, you know which to eat and which to skip (or eat just roots, or flowers, seeds, each plant is different).

          • John Thompson

            You can’t live on celery, though you can eat it.
            Net negative calories.
            Many leaves are like that.

          • Maia

            Fiber is essential for human health, it’s not all digested, but it feeds the bacteria in your gut and makes you “regular”, and much less likely to develop intestinal cancer and other diseases. Why are you so afraid of leaves?? Been shown countless time that diets high in green leafy vegetables (and weeds, etc) are the healthiest.

          • John Thompson

            I’m not afraid of leaves.
            I’m merely pointing out that most leaves cannot be eaten by humans.
            So name a society of humans that just ate leaves and did well doing that…..
            Unlike Gorillas, humans cannot break down fiber.
            You’ll kill a person with a gorilla diet.

          • Maia

            No society needs to choose between leaf-eating and none leaf-eating, humans eat leaves AND lots of other things, but again, the scientifically proven healthiest diet includes a lot of leafy greens. Among those, wild greens are far more nutritious than most crop-greens.

          • John Thompson

            But you can admit that the gorilla diet would be unhealthy for humans, no matter what bacteria we had – right?

          • Maia

            Here’s what I will admit: a diet of 100% leaves would not be healthy for a human over an extended period of time. But no one has argued for or advocated such a diet!

          • John Thompson

            “What Gorilla poop reveals about our own LOUSY diets”.
            “Researchers analyzing the gut microbes of gorillas and other primates found seasonal shifts that underscore just how much is missing from the modern human diet”
            The title and first sentence clearly imply some kind of superiority of gorilla diet to our own.

  • William Parker

    With their superior diet, why is there life span only 50 years?
    A 50 year old human is conceded still young. Hot dogs & all.

    • Maia

      Different species, sir, that’s why. It’s not that they are dying earlier of disease, it’s genetics.ON the other hand, most American humans over 50 have several chronic diseases and take multiple drugs.

      • William Parker

        The average age for both Male & females in the US is over 70. The average take in the chronic ones.

        • John Thompson

          I think you mean the average life expectancy.
          I too saw the implication that it’s a “superior” diet, but that’s not proven in any way in the article.
          We don’t know that a different diet wouldn’t be even better for Gorillas.
          We certainly do know that eating leaves and bark is not superior in humans, they tried it recently in North Korea and it didn’t work so well.

        • Maia

          The overall health in US is not even close to being near the top of list, nor is longevity. Aren’t you curious why?

          • John Thompson

            We exercise the least. We use the most illegal and legal drugs. And last time I checked only Mexico was more over weight.
            We have lots of car crashes and homicides – plenty of suicides too.
            There are so many things.
            Heck, we reduced smoking significantly but life expectancy dipped a bit.
            We still have a longer life expectancy than many places with a more natural/ancient diet – so it’s complicated.

  • nik

    Is it just possible that the bacteria that break down the respective foods, actually originates in those foods? It would be an obvious evolution adaptation for bacteria to adopt, and bacteria have been around on Earth as long as there was an environment to support them.
    So, if you eat any sort of food, unprocessed, then the bacteria required to digest it, naturally comes along with it.

    • John Thompson

      This is an area where we really don’t completely know.
      My guess is if that bacteria was in the food, it would then lead to premature spoilage of the food.
      In the animal kingdom, many creatures actually eat feces of others, which helps them acquire digestive bacteria.
      Person to person/mother to child spreading of intestinal bacteria happens.
      We tend to focus on when harmful intestinal bacteria pass from person to person – but good ones can also spread from person to person.
      Ironically, while those bacteria may not be in the food, they may be on the food due to handling and environmental reasons.
      Many of these gut bacteria can’t live outside the gut – so there is that to consider.

      • nik

        What I had in mind, was the agents that exist on grapes, that cause fermentation. They are ideal for the job of making wines, as they are fully adapted to the particular plants.
        So, many similar agents may exist on other plants that they are most adapted to.

        • John Thompson

          Yeast is added to grape juice to make the fermentation happen. They use particular yeasts for making particular wines – there are some that are most commonly used.
          You wouldn’t get that to happen just from the grapes/grape juice itself.
          You could leave it open to the air to get wild yeast from the air – in wine country that might be a wine making yeast just by chance – but often wild yeast makes something undrinkable.
          Same with beer, same with bread.
          Humans isolated the yeasts that work properly – among many that didn’t – and humans have propagated those particular yeasts and add them deliberately.

          • Maia

            Yeasts AND certain bacteria do the fermenting.

          • John Thompson

            Yeast being essential or there is no alcohol. Addition of bacteria is optional.
            In some wines they make sure to exclude bacteria (as much as possible).

  • Maia

    Eating seasonally is not only better for bacteriomes and humans, but planets, too. Those winter raspberries have to be flown in using lots of polluting jet fuel.

    • John Thompson

      Would it be better or worse “for the planet” if no life existed?

  • Peter Lewicke

    The diets of humans and gorillas are very different, and for that reason one would expect the intestinal flora to be different in the two species. The lack of annual turnover in human flora is due to the relative constancy of human diet, although it is somewhat variable in some areas, but it does not change drastically.

    • John Thompson

      And I didn’t see any reason listed why it would be a problem to have a consistent diet with the same intestinal flora.

      • Maia

        All diets and their particular microbiomes are not equally healthy, overall. A consistent lack of fiber, eg, is not good for many reasons, though there are microbiomes that “go with” a low fiber diet.

  • John Thompson

    That would be ON the food, not IN the food.
    BTW, how have you not made wine yet from raw grapes if you did use “must”?
    Again, as I also mentioned, you can allow wild yeast that can be on the grapes, or in the air to ferment it.

    • http://www.tipofthespearblog.com/ Domenico Tassone

      What is the point of the distinction? To be specific, the yeast starts off ON the grape; when it is made into a must it is then IN the food. You can buy 5 gallon buckets of refrigerated must when it is in season; sometimes they sell it frozen. Many hobby wine-makers, restaurants and others use the natural method. Commercial vintners do not because they seek consistency in the results.

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