Why Life Needs Death
Question: What is the importance of death to evolution?
Tyler Volk: Without death, there’s no evolution; at least as far as we know it. One could hypothesize some organism that might live forever that would butt off mutations, but evolution as it works now, operates by organisms dying and the next generations carry on. And those generations, for the most part, have variance in them and then those variants are selected. So you can get a sort of design happening out of evolution over time, or you can get adaptations occurring that did not exist. So, for example, at one point there were no large creatures such as us, or elephants, or dinosaurs, or amphibians walking on land. There were vertebrates called fish in the world’s oceans and then they were about to emerge and to go up on land. The only way that could happen would be many generations dying. Many generations of fish with certain kinds of limbs dying and there were slow variations accumulating to turn those fish into tetrapods, four-legged creatures, that would either being the mud, or in the shallow water and eventually crawl up out of the ocean. So, death has really been an essential ingredient to the evolutionary process.
Question: Why are cells constantly being recycled in our bodies?
Tyler Volk: Cells are dying in our bodies all the time. The rates that they die and are replaced vary depending on what organ we’re looking at. So, for example, the skin – the cells in the skill are turned over approximately every month of time. New cells are migrating outward and old cells are sloughed off. And that makes some sense. The skin is subject to a lot of wear and tear and abrasion; it is in contact with a harsh environment. So for the skin to have some kind of way to renew itself is very essential to having a border around our bodies. Organs, such as the brain and the heart, the cells there – many of those cells, either aren’t intended to die, they don’t really have turnover. And some part of the brain it is being discovered, the cells do have turnover, but clearly the places such as the brain and the heart in which the interconnectivity of the cells and the cells working together, is really crucial in those organs that turnover is a lot less.
So the body, through the evolutionary process, has tuned death in a kind of adaptive manner to insure that these organs are healthy depending on what function these organs have to play.
There’s also a role of death in development that all large creatures that we know, have. A really good example is our hand with our five fingers. The fingers do not grow as stems of a tree might grow in which they start small and they just grow outward. You might think that happens that they are starting – of course they’re small in the womb. But instead, the hand starts off as like a paddle. Sort of a thick, very thick ping-pong paddle. And the fingers in this embryonic stage are formed by the cells in between dying off. So the first extension of the fingers is formed by a developmental form of death. It’s a programmed death. This is death being controlled. It’s not just the turnover that I described earlier of the skin turning over, but these cells die in between. And they don’t die and then fall away. They die and are reabsorbed into the hand, and so it’s a form of recycling. But the formation of the hand; and this is true of the human hand, the mouse hand, there’s many examples of this. And if there is not controlled, what’s called programmed cell death, very precisely sculpting the developing organism, it’s been show that these organisms can die that death is absolutely essential in the early developmental process.
Question: How is death essential to life?
Tyler Volk: Yeah. One thing I write about is the fact that there’s not just one death, there’s different forms of death. There’s the death of our bodies that has to do with the essence of us being a large multi-cellular creature, a metazoan having to do with the slowing down of the repair mechanisms. But there’s also a lot of death inside our bodies as we live. The death of our cells, skin cells are always sloughing off, internal cells are dying, cells that are abhorrent; go through a kind of suicide program. So, there’s a lot of death inside our bodies all the time going on that is essential to our life. And this is somewhat of a different death from the death of our bodies as large organisms.
And then there’s also death on small scales, in bacteria, that either have to do with running out of nutrients that is an inadvertent form of death, but there’s also kinds of bacteria which are multi-cellular, and they can program cell death as they go into reproductive phases. So, one issue about death that I find particularly fascinating is that there is not just one kind of death, but death has been really incorporated into life in various forms depending on what scale of nature we’re looking at.
Tyler Volk: Yeah. One thing I write about is the fact that there’s not just one death, there’s different forms of death. There’s the death of our bodies that has to do with the essence of us being a large multi-cellular creature, a metazoan having to do with the slowing down of the repair mechanisms. But there’s also a lot of death inside our bodies as we live. The death of our cells, skin cells are always sloughing off, internal cells are dying, cells that are abhorrent; go through a kind of suicide program. So, there’s a lot of death inside our bodies all the time going on that is essential to our life. And this is somewhat of a different death from the death of our bodies as large organisms.
And then there’s also death on small scales, in bacteria, that either have to do with running out of nutrients that is an inadvertent form of death, but there’s also kinds of bacteria which are multi-cellular, and they can program cell death as they go into reproductive phases. So, one issue about death that I find particularly fascinating is that there is not just one kind of death, but death has been really incorporated into life in various forms depending on what scale of nature we’re looking at.
From our tiniest cells performing constant "suicide programs," to the adaptive measures behind the grand sweep of evolutionary history, death is what truly drives life.
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New study suggests placebo might be as powerful as psychedelics
New study suggests the placebo effect can be as powerful as microdosing LSD.
- New research from Imperial College London investigated the psychological effects of microdosing LSD in 191 volunteers.
- While microdosers experienced beneficial mental health effects, the placebo group performed statistically similar to those who took LSD.
- Researchers believe the expectation of a trip could produce some of the same sensations as actually ingesting psychedelics.
Psychedelics: The scientific renaissance of mind-altering drugs
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="92360c805fe66c11de38a75b0967f417"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/5T0LmbWROKY?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>For the study published in eLife, the team recruited 191 citizen cosmonauts to microdose either LSD or a placebo over the course of several weeks and note the psychological effects. Volunteers were already microdosing LSD, so there was no true control. Each volunteer was given instructions on creating their own low-dose gel capsules, some containing LSD, others not. Then they mixed the capsules in envelopes so they didn't know if they were taking the real thing or not.</p><p>The trial design was ingenious: each capsule featured a QR code that was scanned after the addition of ingredients but before they were placed in the envelope so that researchers knew what they were ingesting.</p><p>The problem: volunteers sourced their own LSD. Lack of quality control could have had a profound effect on the results. </p><p>The results: LSD microdosers reported feeling more mindful, satisfied with life, and better overall; they also noticed a reduction in feelings of paranoia. </p><p>The catch: the control group felt the same thing, with no statistical difference between the groups. </p><p>Lead author Balázs Szigeti comments on the findings: "This suggests that the improvements may not be due to the pharmacological action of the drug but can instead be explained by the placebo effect." </p>Credit: Alexander / Adobe Stock
<p>Psychedelics are notoriously difficult to control for given the intensity of the experience. Yet there is precedent for the above findings. A <a href="https://link.springer.com/article/10.1007/s00213-020-05464-5" target="_blank">2019 study</a> found that 61 percent of volunteers that took a placebo instead of psilocybin felt some psychedelic effects, with a few volunteers experiencing full-on trips.</p><p style="margin-left: 20px;">"Several stated that they saw the paintings on the walls 'move' or 'reshape' themselves, others felt 'heavy. . . as if gravity [had] a stronger hold', and one had a 'come down' before another 'wave' hit her."</p><p>The Imperial team believes the expectation of a trip might have been enough to produce similar results. Senior author David Erritzoe is excited for future studies on the topic, believing they tapped into a new wave of citizen science that could push forward our knowledge of psychedelic substances.</p><p style="margin-left: 20px;">"Accounting for the placebo effect is important when assessing trends such as the use of cannabidiol oils, fad diets or supplements where social pressure or users' expectations can lead to a strong placebo response. Self-blinding citizen science initiatives could be used as an inexpensive, initial screening tool before launching expensive clinical studies."</p><p>As investments into the psychedelics market explode, with one company <a href="https://www.bloomberg.com/news/articles/2021-03-03/thiel-backed-magic-mushroom-firm-atai-hits-2-billion-valuation" target="_blank">reaching a $2 billion valuation</a>, a recurring irony appears in the long arc of psychedelics and research: the power of our minds might be enough to feel greater life satisfaction and a deeper sense of mindfulness. If that's possible with a placebo, we have to question why the rush to create more pharmacology is necessary. </p><p>This is, mind you, a separate conversation over the role of psychedelics and rituals for group bonding. The function of group cohesion around consciousness-altering substances will continue to play an important role in many communities. </p><p>Of course, we should continue to explore the efficacy of psychedelics on anxiety, depression, suicidal ideation, PTSD, and addiction. <a href="https://bigthink.com/surprising-science/antidepressant-effects" target="_self">Pharmacological dependence</a> is a stain on the psychiatry industry. Whether or not psychedelics can be prescribed for daily use remains to be seen, but we know a moneyed interest is expecting a return on investment—the above company, ATAI Life Sciences, raised $157 million in its Series D round. </p><p>When it comes to wellbeing, some things money just can't buy. How we navigate the tricky terrain of mainstreaming psychedelics remains to be seen. </p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank" rel="noopener noreferrer">Facebook</a>. His most recent book is</em> "<em><a href="https://www.amazon.com/gp/product/B08KRVMP2M?pf_rd_r=MDJW43337675SZ0X00FH&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee" target="_blank" rel="noopener noreferrer">Hero's Dose: The Case For Psychedelics in Ritual and Therapy</a>."</em></p>Your genetics influence how resilient you are to the cold
What makes some people more likely to shiver than others?
Some people just aren't bothered by the cold, no matter how low the temperature dips. And the reason for this may be in a person's genes.
Dogs digest human food better and poop less
A new study finds that dogs fed fresh human-grade food don't need to eat—or do their business—as much.
- Most dogs eat a diet that's primarily kibble.
- When fed a fresh-food diet, however, they don't need to consume as much.
- Dogs on fresh-food diets have healthier gut biomes.
Four diets were tested
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NjY0NjIxMn0._w0k-qFOC86AqmtPHJBK_i-9F5oVyVYsYtUrdvfUxWQ/img.jpg?width=980" id="1b1e4" class="rm-shortcode" data-rm-shortcode-id="87937436a81c700a8ab3b1d763354843" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />Credit: AntonioDiaz/Adobe Stock
<p>The researchers tested refrigerated and fresh human-grade foods against kibble, the food most dogs live on. The <a href="https://frontierpets.com.au/blogs/news/how-kibble-or-dry-dog-food-is-made" target="_blank">ingredients</a> of kibble are mashed into a dough and then extruded, forced through a die of some kind into the desired shape — think a <a href="https://en.wikipedia.org/wiki/Food_extrusion" target="_blank">pasta maker</a>. The resulting pellets are sprayed with additional flavor and color.</p><p>For four weeks, researchers fed 12 beagles one of four diets:</p><ol><li>a extruded diet — Blue Buffalo Chicken and Brown Rice Recipe</li><li>a fresh refrigerated diet — Freshpet Roasted Meals Tender Chicken Recipe</li><li>a fresh diet — JustFoodforDogs Beef & Russet Potato Recipe</li><li>another fresh diet — JustFoodforDogs Chicken & White Rice Recipe.</li></ol><p>The two fresh diets contained minimally processed beef, chicken, broccoli, rice, carrots, and various food chunks in a canine casserole of sorts. </p><p>(One can't help but think how hard it would be to get finicky cats to test new diets. As if.)</p><p>Senior author <a href="https://ansc.illinois.edu/directory/ksswanso" target="_blank" rel="noopener noreferrer">Kelly S. Swanson</a> of U of I's Department of Animal Sciences and the Division of Nutritional Sciences, was a bit surprised at how much better dogs did on people food than even refrigerated dog chow. "Based on past research we've conducted I'm not surprised with the results when feeding human-grade compared to an extruded dry diet," he <a href="https://aces.illinois.edu/news/feed-fido-fresh-human-grade-dog-food-scoop-less-poop" target="_blank">says</a>, adding, "However, I did not expect to see how well the human-grade fresh food performed, even compared to a fresh commercial processed brand."</p>Tracking the effect of each diet
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3NjY1NTgyOX0.AdyMb8OEcjCD6iWYnXjToDmcnjfTSn-0-dfG96SIpUA/img.jpg?width=980" id="da892" class="rm-shortcode" data-rm-shortcode-id="880d952420679aeccd1eaf32b5339810" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />Credit: Patryk Kosmider/Adobe Stock
<p>The researchers tracked the dogs' weights and analyzed the microbiota in their fecal matter.</p><p>It turned out that the dogs on kibble had to eat more to maintain their body weight. This resulted in their producing 1.5 to 2.9 times the amount of poop produced by dogs on the fresh diets.</p><p>Says Swanson, "This is consistent with a 2019 National Institute of Health study in humans that found people eating a fresh whole food diet consumed on average 500 less calories per day, and reported being more satisfied, than people eating a more processed diet."</p><p>Maybe even more interesting was the effect of fresh food on the gut biome. Though there remains much we don't yet know about microbiota, it was nonetheless the case that the microbial communities found in fresh-food poo was different.</p><p>"Because a healthy gut means a healthy mutt," says Swanson, "fecal microbial and metabolite profiles are important readouts of diet assessment. As we have shown in <a href="https://academic.oup.com/jas/article/92/9/3781/4702209#110855647" target="_blank">previous studies</a>, the fecal microbial communities of healthy dogs fed fresh diets were different than those fed kibble. These unique microbial profiles were likely due to differences in diet processing, ingredient source, and the concentration and type of dietary fibers, proteins, and fats that are known to influence what is digested by the dog and what reaches the colon for fermentation."</p>How did kibble take over canine diets?
<p>Historically, dogs ate scraps left over by humans. It has only been <a href="https://www.thefarmersdog.com/digest/the-history-of-commercial-pet-food-a-great-american-marketing-story/" target="_blank">since 1870</a>, with the arrival of the luxe Spratt's Meat Fibrine Dog Cakes—made from "the dried unsalted gelatinous parts of Prairie Beef", mmm—that commercial dog food began to take hold. Dog bone-shaped biscuits first appeared in 1907. Ken-L Ration dates from 1922. Kibble was first extruded in 1956. Pet food had become a great way to turn <a href="https://www.dogfoodadvisor.com/choosing-dog-food/animal-by-products/" target="_blank">human-food waste</a> into profit.</p><p>Commercial dog food became the norm for most household canines only after a massive marketing campaign led by a group of dog-food industry lobbyists called the Pet Food Institute in 1964. Over time, for most households, dog food was what dogs ate — what else? Human food? These days more than half of U.S. dogs are <a href="https://www.nytimes.com/2014/08/03/magazine/who-made-that-dog-biscuit.html" target="_blank">overweight or obese</a>, and certainly their diet is a factor.<span></span></p><p>We're not so special among animals after all. If something's healthy for us to eat—we're <em>not</em> looking at you, chocolate—maybe we should remember to share with our canine compatriots. Not from the table, though.</p>Harvard study finds perfect blend of fruits and vegetables to lower risk of death
Eating veggies is good for you. Now we can stop debating how much we should eat.
- A massive new study confirms that five servings of fruit and veggies a day can lower the risk of death.
- The maximum benefit is found at two servings of fruit and three of veggies—anything more offers no extra benefit according to the researchers.
- Not all fruits and veggies are equal. Leafy greens are better for you than starchy corn and potatoes.
