Over 2 billion people across 100 countries eat insects as part of their regular or traditional diet. But in the Western world, where meat consumption (and indeed the consumption of food in general) is disproportionately high, making bugs an accepted part of the menu can be especially beneficial — if not difficult, given the obvious taboos (there is a reason insects are only eaten in the context of reality shows or as part of gross-out humor).
I say losing fat as opposed to losing weight because the latter is too broad: if excess weight is due to larger muscle mass for example, it is (usually) far less troubling for health reasons. When people speak of losing weight, they really mean improving the ratio of fat to muscle in their bodies (hence the phenomenon of “skinny fat“, in which someone appears slim in both appearance and scale results, but has a disproportionate amount of fat relative to muscle).
With all that cleared up, I know what many people are thinking: another study countering what so many other studies have previously established. This seems to be a perennial problem in nutritional science, which is still a young and developing field full of unknowns and rife with difficulties in conducting research (there are so many variables affecting health and weight among individuals that it takes unfeasible large and long-term studies to get solid, measurable results — hence why so many conventional wisdoms are being challenges decades later following the build-up of many studies).
Anyway, take the following report in the Washington Post as you will. From what I have read on the subject, the claims of these researchers do seem well-substantiated, but feel free to present your own arguments. Continue reading
Each year, more than 50 million deaths occur around the globe—and for all but a fraction, the actual cause goes unrecorded. That’s a major obstacle to improving public health: How can we save lives if we don’t understand what threatens them?
Read more on the The Atlantic to find out about this understated issue.
Utilizing USDA data, Vox.com has produced acolorful graph that charts the vast changes in the average American’s diet since 1972. (Note that it shows the total supply of these items divided by the number of Americans, rather than exact consumption levels. However, this nonetheless gives a good sense of how eating patterns are changing over time, especially insofar as supply both reflects and often influences demand.)
Here is some analysis from the article:
[Y]ou might notice there are a lot of olive-green bars toward the bottom. We’re all eating a lot more fresh fruits and vegetables than we used to. That’s in part a story about changing tastes, but it’s also about economics — globalization and trade deals like NAFTA have given Americans more access to a wealth of fruits such as limes and avocados. And it appears those foods have replaced preserved or processed produce — many of the foods whose availability has shrunk are those maroon bars that represent canned, frozen, or dried produce.
While we’re eating a lot more fresh fruits and veggies than before, we’re not getting healthier all around. High-fructose corn syrup consumption has skyrocketed. Back in 1972 — right around the time that it was first introduced — we had 1.2 pounds per capita of the syrup available to us. Today, it’s 46.2 pounds … and that’s in fact down substantially from a high of 63 pounds in 1999.
Of course, don’t let the numbers fool you on a few of these — some of the massive growth came because of very small numbers. For example, it’s not that we’re eating piles and piles of lima beans today; rather, it’s that we were eating only 0.0005 pounds in 1989 versus 0.007 pounds in 2012 — a huge percentage gain in growth from an initially very small number.
What are your thoughts and reactions?
The Atlantic reports on yet another study confirming the benefits of exposure oneself to nature, even for literally a glimpse.
A nice walk through a city park can do wonders for a work-weary brain, reducing mental fatigue and improving attention. But if you’re trapped on the high floors of an office tower all day, you can’t exactly break for a long stroll and a picnic. Well, fear not. If you have a view of a nearby green space, like say a green roof, and even just a minute to spare, you can reap some of the same refreshing benefits of urban nature.
That’s the upshot of a new paper from an Australia-based research team set for publication in the Journal of Environmental Psychology. Their work has found that even taking just 40 seconds to focus on a view of nature can boost “multiple networks of attention”—sharpening your mind to handle the next task dealt by the work day. They call it a “micro-break,” and it turns out your brain loves it:
You can read the details and methodology of the study in the article, but it is certainly not the only research to confirm the importance of nature to human well-being:
The findings certainly fit with all that social science has found in recent years about the restorative power of nature. Whether it’s a walk through a park, a stand of trees out the window, or a mere desk plant, natural views give the working brain a breather—to varying degrees—by engaging our involuntary attention centers. The new conclusion that greenery might work its magic in mere minutes is an especially intriguing prospect in a fast-paced work world. And if green roof simulations were replaced with the real thing, the performance outcomes in the current study might even have been stronger.
I can certainly vouch for this by personal experience. From my regular bouts of anxiety and depression, to good old fashioned work-related stress, pausing for just a moment to focus on my desk plant, visit my garden, or take a stroll through a nearby park has done wonders.
I am glad to work just blocks away from a beautiful public park (and more glad that my job lets me take regular walk breaks). Since I have incorporated this practice into my daily routine, I have seen a notable decline in both the frequency and severity of stress, fatigue, and sadness (although other lifestyle and dietary changes have continued to that as well).
But a few minutes is all it takes to try this out and see the difference.
Mindfulness meditation is one of the biggest trends in both medical and New Age circles. It broadly describes a form of mental training in which one deliberately focuses on emotions, thoughts, and sensory experiences of the present moment. Though it has roots in various religious traditions both Western and Eastern (especially Buddhism), it has long been observed to have secular applications as well, and the practice itself does not require any particular religious ritual or component.
There has been a lot of research showing that mindfulness, like meditation as a whole, has tangible mental and physical health benefits. The most recent study to confirm the benefits of “mindfulness-based cognitive therapy (MBCT)”, as it is known in medical parlance, was published in The Lancet, a leading medical journal. As Al Jazeera reported:
In this study, 424 adults in England with recurrent major depression, who were on maintenance antidepressant drugs, were randomly assigned to go off their antidepressants slowly and receive MBCT or to stay on their medication.
Study results published showed that after two years, relapse rates were similar in both groups — 44 percent in the therapy group versus 47 percent in the antidepressant drug group.
“Mindfulness gives me a set of skills which I use to keep well in the long term”, Nigel Reed, a participant in the study, said in a statement. “Rather than relying on the continuing use of antidepressants, mindfulness puts me in charge, allowing me to take control of my own future, to spot when I am at risk and to make the changes I need to stay well”.
The researchers said that while they found no evidence that [mindfulness] was superior to the use of antidepressants in preventing relapse, they said “both treatments were associated with enduring positive outcomes in terms of relapse or recurrence, residual depressive symptoms and quality of life”.
“We believe these results suggest a new choice for the millions of people with recurrent depression on repeat prescriptions”, Kuyken said.
I can personally vouch for the effectiveness of this approach, although it is worth reiterating that this is just one of several ways to combat depression, and by no means is it a wholesale replacement of other therapies (indeed, it is usually complementary).
Solutions will always vary from individual to individual, but with the rate of depression growing across the world, any new options on the table will certainly help; moreover, mindfulness techniques are beneficial to overall wellness, not just as a therapy for depression.
Addiction has long been the subject of intense personal criticism, attributed to personal irresponsibility, negligence, or immorality. But centuries of this approach have done little to mitigate it; if anything, social or legal punishments make the problem worse, breeding psychological distress and resentment that further reinforce, if not escalate, the addiction.
A cynic might chalk the persistence of this social ill to the vagaries of human nature, e.g. bad, stupid, or irresponsible have always existed and always will. No amount of medical, legal, or social support will do anything about it. Locking up addicts or ostracizing them is the most we can do to remove the problem.
But there is mounting research, going back over three decades, that shows substance abuse to have more complex and external origins that go well beyond personal fiat. As HuffPo reported:
One of the ways this theory was first established is through rat experiments – ones that were injected into the American psyche in the 1980s, in a famous advert by the Partnership for a Drug-Free America. You may remember it. The experiment is simple. Put a rat in a cage, alone, with two water bottles. One is just water. The other is water laced with heroin or cocaine. Almost every time you run this experiment, the rat will become obsessed with the drugged water, and keep coming back for more and more, until it kills itself.
The advert explains: “Only one drug is so addictive, nine out of ten laboratory rats will use it. And use it. And use it. Until dead. It’s called cocaine. And it can do the same thing to you”.
But in the 1970s, a professor of Psychology in Vancouver called Bruce Alexander noticed something odd about this experiment. The rat is put in the cage all alone. It has nothing to do but take the drugs. What would happen, he wondered, if we tried this differently? So Professor Alexander built Rat Park. It is a lush cage where the rats would have colored balls and the best rat-food and tunnels to scamper down and plenty of friends: everything a rat about town could want. What, Alexander wanted to know, will happen then?
In Rat Park, all the rats obviously tried both water bottles, because they didn’t know what was in them. But what happened next was startling.
The rats with good lives didn’t like the drugged water. They mostly shunned it, consuming less than a quarter of the drugs the isolated rats used. None of them died. While all the rats who were alone and unhappy became heavy users, none of the rats who had a happy environment did.
Before anyone points out the obvious fact that rats are not humans, and thus not a reliable basis on which to base our addiction solutions on, it turns out that the Vietnam War, of all things, bolstered the study’s conclusion as well:
Time magazine reported using heroin was “as common as chewing gum” among U.S. soldiers, and there is solid evidence to back this up: some 20 percent of U.S. soldiers had become addicted to heroin there, according to a study published in the Archives of General Psychiatry. Many people were understandably terrified; they believed a huge number of addicts were about to head home when the war ended.
But in fact some 95 percent of the addicted soldiers — according to the same study — simply stopped. Very few had rehab. They shifted from a terrifying cage back to a pleasant one, so didn’t want the drug any more.
Professor Alexander argues this discovery is a profound challenge both to the right-wing view that addiction is a moral failing caused by too much hedonistic partying, and the liberal view that addiction is a disease taking place in a chemically hijacked brain. In fact, he argues, addiction is an adaptation. It’s not you. It’s your cage.
In other words, addiction is shaped as much, if not more, by the individual’s social environment than any chemical reaction or moral perspective. This makes sense when one considers that fundamentally social nature of humans, and how our behaviors, actions, and pathologies are influenced by a wide range of external factors, ranging from the physical environment to the support of our fellow humans.
Here’s one example of an experiment that is happening all around you, and may well happen to you one day. If you get run over today and you break your hip, you will probably be given diamorphine, the medical name for heroin. In the hospital around you, there will be plenty of people also given heroin for long periods, for pain relief. The heroin you will get from the doctor will have a much higher purity and potency than the heroin being used by street-addicts, who have to buy from criminals who adulterate it. So if the old theory of addiction is right — it’s the drugs that cause it; they make your body need them — then it’s obvious what should happen. Loads of people should leave the hospital and try to score smack on the streets to meet their habit.
But here’s the strange thing: It virtually never happens. As the Canadian doctor Gabor Mate was the first to explain to me, medical users just stop, despite months of use. The same drug, used for the same length of time, turns street-users into desperate addicts and leaves medical patients unaffected.
If you still believe — as I used to — that addiction is caused by chemical hooks, this makes no sense. But if you believe Bruce Alexander’s theory, the picture falls into place. The street-addict is like the rats in the first cage, isolated, alone, with only one source of solace to turn to. The medical patient is like the rats in the second cage. She is going home to a life where she is surrounded by the people she loves. The drug is the same, but the environment is different.
This gives us an insight that goes much deeper than the need to understand addicts. Professor Peter Cohen argues that human beings have a deep need to bond and form connections. It’s how we get our satisfaction. If we can’t connect with each other, we will connect with anything we can find — the whirr of a roulette wheel or the prick of a syringe. He says we should stop talking about ‘addiction’ altogether, and instead call it ‘bonding.’ A heroin addict has bonded with heroin because she couldn’t bond as fully with anything else.
So the opposite of addiction is not sobriety. It is human connection.
I recommend reading the rest of the article, but the conclusion is clear: when addressing addiction at both an individual and community level, it is vital to go beyond the biological or psychological factors and take into account the context — the state of the addict’s social life, the sort of bonds or lack thereof in their life, etc. A more holistic view takes into account all the relevant details.
Obviously, more research is needed to explore this issue, but it is definitely interesting and important to take into account every possible variable.
One of the major motivations to eat healthy, exercise regularly, and engage in healthy lifestyles is to enjoy a long and quality life. Most people want to enjoy as many fruitful and productive years as possible, and thankfully advances in medicine and nutrition are making it easier than ever.
But the key to longevity and productive old age may be a lot simpler and more accessible, if the world’s “Blue Zones” are any indication. These are regions in the world – Ikaria, Greece; Okinawa, Japan; Ogliastra Region, Sardinia; Loma Linda, California; and Nicoya Peninsula, Costa Rica – that are known for having the highest number of centenarians (those living at or past 100) in the world.
In fact, not only do these Blue Zoners live long lives, but perhaps more importantly, they enjoy fairly robust mental and physical faculties: despite their advanced age, they are active, alert, happy, and lacking the diseases and disabilities that usually afflict people decades younger, let alone at or near 100.
So what do people in these communities – which span different cultures, climates, and environments – do to stay so healthy for so long?
Well, they each have their differences: for example, Sardinians consume a lot of fava beans and red wine, residents of Loma Linda, California are known for eating copious amounts of nuts and legumes, and Okinawans heavily utilize the spice turmeric in their diet.
This suggests that there are different paths to having a long and healthy life. But the similarities are what are especially informative. Here is a breakdown from NPR:
You may remember this Blue Zone from Buettner’s wonderful 2012 New York Times Magazine article entitled “The Island Where People Forget To Die.”
As we’ve reported, health researchers have long praised the Mediterranean diet for promoting brain and physical health and keeping chronic diseases at bay. So what makes the diet of the people on Ikaria, a small island in the Aegean Sea, so special?
“Their tradition of preparing the right foods, in the right way, I believe, has a lot to do with the island’s longevity,” writes Buettner.
And “what set it apart from other places in the region was its emphasis on potatoes, goat’s milk, honey, legumes (especially garbanzo beans, black-eyed peas, and lentils), wild greens, some fruit and relatively small amounts of fish.”
Ikaria has a few more “top longevity foods:” feta cheese, lemons and herbs like sage and marjoram that Ikarians use in their daily tea. What’s missing that we usually associate with Greece? Lamb. The Ikarians do eat some goat meat, but not often.
Buettner calls the islands of Okinawa a kind of “Japanese Hawaii” for their laid-back vibe, beaches and fabulous weather. Okinawa also happens to have one of the highest centenarian ratios in the world: About 6.5 in 10,000 people live to 100 (compare that with 1.73 in 10,000 in the U.S.)
Centenarians on Okinawa have lived through a lot of upheaval, so their dietary stories are more complicated than some of the other Blue Zones. As Buettner writes, many healthful Okinawan “food traditions foundered mid-century” as Western influence brought about changes in food habits. After 1949, Okinawans began eating fewer healthful staples like seaweed, turmeric and sweet potato and more rice, milk and meat.
Still, Okinawans have nurtured the practice of eating something from the land and the sea every day. Among their “top longevity foods” are bitter melons, tofu, garlic, brown rice, green tea and shitake mushrooms.
On this beautiful island in the middle of the Mediterranean, the ratio of centenarian men to women is one to one. That’s quite unusual, because in the rest of the world, it’s five women to every one man who live that long.The sharp pecorino cheese made from the milk of grass-fed sheep in Sardinia, has high levels of omega-3 fatty acids.
Buettner writes that the Sardinians explain their exceptional longevity with their assets such as “clean air,” “locally produced wine,” or because they “make love every Sunday.” But when Buettner brought along a researcher to dig deeper, they found that pastoralism, or shepherding livestock from the mountains to the plains, was most highly correlated with reaching 100.
So what are those ancient Sardinian shepherds eating? You guessed it: goat’s milk and sheep’s cheese — some 15 pounds of cheese per year, on average. Also, a moderate amount of carbs to go with it, like flat bread, sourdough bread and barley. And to balance those two food groups out, Sardinian centenarians also eat plenty of fennel, fava beans, chickpeas, tomatoes, almonds, milk thistle tea and wine from Grenache grapes.
Loma Linda, Calif.
There’s a Blue Zone community in the U.S.? We were as shocked to learn this as you may be. Its members are Seventh-day Adventists who shun smoking, drinking and dancing and avoid TV, movies and other media distractions.Tofu links sold in Loma Linda, Calif. The Blue Zones research shows that adherents of the Adventist diet, which is mostly plant-based, have lowest rates of heart disease and diabetes in the U.S. and very low rates of obesity.
They also follow a “biblical” diet focused on grains, fruits, nuts and vegetables, and drink only water. (Some of them eat small amounts of meat and fish.) Sugar is taboo, too. As one Loma Linda centenarian tells Buettner: “I’m very much against sugar except natural sources like fruit, dates or figs. I never eat refined sugar or drink sodas.”
Gary Fraser, a cardiologist and epidemiologist at Loma Linda University and an Adventist himself, has found in studies that Adventists who follow the religion’s teachings lived about 10 years longer than people who didn’t. Another key insight? Pesco-vegetarians in the community, who ate a plant-based diet with up to one serving of fish a day, lived longer than vegan Adventists.
Their top foods include avocados, salmon, nuts, beans, oatmeal, whole wheat bread and soy milk.
Nicoya Peninsula, Costa Rica
We’d love to be invited for dinner by a centenarian here, where they #putaneggonit all the time. One delicious-sounding meal Buettner was served by a 99-year-old woman (who’s now 107) consisted of rice and beans, garnished with cheese and cilantro, on corn tortillas, with an egg on top.
As Buettner writes, “The big secret of the Nicoyan diet was the ‘three sisters’ of Mesoamerican agriculture: beans, corn and squash.” Those three staples, plus papayas, yams, bananas and peach palms (a small Central American oval fruit high in vitamins A and C), are what fuel the region’s elders over the century.
Here is a visual of the data from three of the earliest discovered Blue Zones (absent Nicoya and Ikaria, though they too meet at the middle):
So to recap: people in Blue Zones tend to enjoy varied diets made up of fresh and whole foods, particularly greens, nuts, herbs, and seafood; they consume portions that are often smaller than average, with an emphasis on eating only enough to be satiated (rather than stuffed); and they tend to eat little meat proportionally, aside from lean cuts and seafood.
Beyond diet, Blue Zone residents engage in regular moderate exercise – usually walking, gardening, or yard work – and also maintain active social and community lives, especially with their families. They maintain an easy-going and slow pace of life, often setting aside time to relax and de-stress. Smoking is also virtually nonexistent.
In short, the people living in Blue Zones work on all dimensions of a healthy life: not just a healthy diet, but a modest and light one; strong social ties with an even stronger, life-affirming dedication to family and the community; and an appreciation of the finer things in life, like a nice walk or time to unwind, which does wonders for mental health.
Though there is still a lot of research to be done, the evidence seems clear: a long and healthy life doesn’t require anything fancy or technological, but the sort of diet and values that are accessible to most of us — at least up to a point.
It is telling that among the handful of similarities common to all the Blue Zones was strong family and social ties and healthy community life. I think it says as much about the importance of building a good and generous society, and what such a relatively prosperous society may look like, then its does about the importance diet (which is just one dimension of overall health and wellness).
Just as physical and mental health are intricately intertwined, so too are individual and community health. It is much easier and more feasible to live a long and healthy life when your society provides the sort of stability, socioeconomic support, and environment to facilitate it all.
When your economic system requires you to work long, punishing hours at too fast of a pace to relax; when your food distribution system makes fresh produce expensive or inaccessible, and conversely makes less healthy processed food plentiful in its place; and when your society lacks mutually beneficial values of generosity and altruism, it is a lot harder for most people to maximize the potential of their minds and bodies.
Here is hoping that Blue Zones become less of an anomaly and more of a model to emulate and expand elsewhere. We see clear examples of the sorts of behaviors and
As humans live longer than ever, it is not surprising that what we define as middle age is also shifting upwards.
A study conducted by researchers from the International Institute for Applied Systems Analysis (IIASA) and Stony Brook University confirmed this, as HuffPo reports:
The researchers used projections of Europe’s population until the year 2050 to look at how an increasing life expectancy changes the definition of “old.” They used different rates of increases, ranging from a stagnant life expectancy to one which grew 1.4 years per decade, to look at the portion of the population who was considered to be old. They looked at both the conventional definition, which considers people over age 65 old, and a new measure, which advances the threshold for old age as overall life expectancy grows.
The findings, published in the journal PLOS ONE, say that as the life expectancy increased with the new measure of old age, the proportion of older people in the population continually fell. The researchers say that we must adjust the threshold we use to determine old age, otherwise the proportion of older people will grow as life expectancy increases.
“What we think of as old has changed over time, and it will need to continue changing in the future as people live longer, healthier lives,” Scherbov said.
It is amazing to live in a time when humans are pushing the limits of both longevity and quality of life: not only are we adding more years to our time on Earth, but we are increasingly managing to maintain relatively healthy mental and physical faculties (especially with regards to Blue Zones and other countries where centenarians are increasingly common).
Given the rapid gains in medicine, nutrition, and public health, who knows how much longer and better people will continue living over the course of the 21st century.
It seems we cannot go a week without scientific and medical institutions (or even the wider public) flip-flopping on the healthiness or unhealthiness of particular foods. Slate explores what this often chaotic and confusing state of affairs says about nutrition science and its present limitations.
The takeaway from the potato controversy is not that lobbyists sometimes base their campaigns on real science. Rather it’s that the David-and-Goliath narrative of science versus Big Ag may be blinding us to another, even bigger problem: the fact that there is often very little solid science backing recommendations about what we eat.
Most of our devout beliefs about nutrition have not been subjected to a robust, experimental, controlled clinical trial, the type of study that shows cause and effect, which may be why Americans are pummeled with contradictory and confounding nutritional advice. Nutritional bad guys that have fallen from grace in the national consciousness—white potatoes, eggs, nuts, iceberg lettuce—have been redeemed years later. Onetime good guys, like margarine and pasta, have been recast as villains. Cholesterol is back in the probably-won’t-kill-you column after being shunned for 40 years, as of the latest nutritional advice from the Dietary Guidelines Advisory Committee in February. (That advice was still too timid, according to Cleveland Clinic cardiologist Steve Nissen, who also wants the nutritional guidelines to admit our best evidence suggests fat isn’t bad for you either). And then there’s salt—don’t eat too little, says the newest research. You could die…
…Many nutritional studies are observational studies, including massive ones like the Nurses’ Health Study. Researchers like Willett try to suss out how changes in diet affect health by looking at associations between what people report they eat and how long they live. When many observational studies reach the same conclusions, Willett says, there is enough evidence to support dietary recommendations. Even though they only show correlation, not cause and effect, observational studies direct what we eat.
Apart from their inability to determine cause and effect, there’s another problem with observational studies: The data they’re based on—surveys where people report what they ate the day (or week) before—are notoriously unreliable. Researchers have long known that people (even nurses) misreport, intentionally and unintentionally, what they eat. Scientists politely call this “recall bias”.
The coupling of observational studies and self-reported data leads some observers to the conclusion that we know neither how Americans do eat nor how they should eat. A recent PLOS One article even suggests that several national studies use data that is so wildly off base that the self-reported caloric intake is “incompatible with survival”. If people had eaten as little as they reported, in other words, they would be starving.
Peter Attia, a medical researcher and doctor, started questioning the basis of dietary guidelines when he saw that following them didn’t work for his patients. They didn’t lose weight, even when they virtuously stuck with their diets. When he took a look at the research supporting the advice he was giving to his patients, he saw shoddy science. Attia estimates that 16,000 nutritional studies are published each year, but the majority of them are deeply flawed: either poorly controlled clinical trials, observational studies, or animal studies. “Those studies wouldn’t pass muster in another field”, he told me.
It is little wonder that quackery, ignorance, and deceit are increasingly taking hold of people’s health decisions. Not only does all this contradictory or ambiguous evidence make room for all sorts of unverified or dangerous claims, but they erode public trust in science and medicine — even if specialists finally get something right with certainty, they will likely be met with incredulity or apathy.
It is not unlike how the inefficiencies of the U.S. health care system, combined with the predations of big pharmaceutical companies, taints evidence-backed medicine as a whole and sends people into the arms of frauds and scammers. With distrust of institutions and authoritative bodies — political, academic, and religious — at an all time high, it seems health and lifestyle choice will be increasingly determined by individual fiat, errors in reasoning, anecdote, or other unreliable bases.
Of course, this is not to condemn all scientific bodies or the scientific approach as a whole. The article makes clear that while a lot of the misconceptions around nutrition and health are attributed to “shoddy” research, various psychological biases, as well as the sheer complexity of measuring all the variables involved with health, make the endeavor a difficult one to pursue in itself.
Ultimately, nutrition science is still a new and burgeoning field of study, and I trust that it will be self-correcting in time, especially now that both the public and establishment are scrutinizing these problems. But while we try to work out better and more reliable ways to learn about what is good for our bodies, there are going to be a lot of mistakes — and outright fakery — made.
Moreover, let us not overstate the problem: while the minutiae and other details are an open questions, there are still general rules that seem to hold true: smoking cigarettes is broadly unhealthy, a plant-centered diet is generally the healthiest, regular physical activity is beneficial, and so on. Of course, we will have to see what more can be said about such conventional health wisdom.