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Nutrition Past and Future

44 Humanity Past and Future

Near the beginning of Robb Wolf's The Paleo Solution, he asks the reader to imagine replacing his or her current view of time, a word that he curiously places in quotation marks, with a view of time he says comes from the ancients. He provides no reference for us to determine the authenticity of this view. We are to just feel his truth as he channels the wisdom of the cavemen and deepens our understanding of time.

"You are in the middle of a river (Time) and facing downstream. The future approaches you from behind - only to recede into the past, which actually lies in front of you, moving ever farther away. If you could look far enough downstream you would see the beginning of the stream and, in essence, everything." Pretty deep, right? I'm not sure what any of that means, though. I'm pretty sure he isn't saying that if you stand in a river imagining you're a caveman that time will pass you by, even though that seems to be the face value message here. No, this is supposed to be pithy. Why he thinks primitives who lacked written language and hunted with stone-tipped spears would have conceptualized time through an extended metaphor, I don't know.

I happen to know a much better metaphorical "river of time" quote which actually relates to evolution in a profound way, and unlike Wolf, I didn't have to make my quote up. It is attributed to Heraclitus. It goes like this: "Into the same river we descend twice and do not descend, for the name of the river remains the same, but the water has flowed on." Sometimes this saying is reformulated to read, "No man ever steps in the same river twice, for it's not the same river and he's not the same man." It makes about as much sense to suggest that evolution has not changed us and everything around us over time as it does to suggest that a river flows today with the same water and in the same way that it flowed in the past.

There is a concept in evolutionary theory called Dollo's law of irreversibility. The idea here is that an organism can never return to a previous stage of its evolution already realized by its ancestors.

Richard Dawkins clarifies what this means in The Ancestor's Tale.

To suggest that we can go backward, or even stay fixed in the same place, is to completely misunderstand evolution. Evolution is about change. That's the meaning of the word. It never moves backward. Even if you think of marine mammals like whales that could be said to have returned from the land to the oceans of their ancestors, they never actually evolved backward. They still bear an inheritance of traits developed during their evolutionary line's stay on dry land. For example, whales are warm-blooded and they breathe into lungs.

Wolf doesn't just think of us as primitives in a biological sense. He wants us to be primitive in our understanding of the world. This is actually how he argues against vegetarianism in his book. "Your protein needs to have the following criteria: 1. It needs a face. 2. It needs a soul. 3. You need to kill it, and bring its essence into your being. 4. Really." Beneath the facade of scientific-sounding distractions the Paleo entrepreneurs have strung together - from lectins to zonulin to xanthine oxidase - the real beliefs at the root of Paleo have nothing to do with science. The ideas are ignorant, primitive, selfish, and cruel.

Wolf has to imagine foolish nutrition scientists who say things no decent scientist would ever say to convince his unsophisticated audience that he knows best. He imagines a PhD saying that evolution "is of limited utility in understanding human beings" to which he replies in his reverie, "so, humans are exempt from the laws of biology?" Yes, Robb Wolf. Humans are exempt from the laws of biology. That's what they teach in research universities now. Scientists wear tofu T-shirts in his fantasies. How crazy is this? How can he not be ashamed of himself for putting such idiocy into writing? And people pay money to read this! Paleo posers feel educated by this!

Actually Mr. Wolf, evolutionary theory is of limited utility in understanding human beings since one cannot reliably apply evolutionary theories to clinical practice. No matter how much you are enthralled with your fantasies, they are still just fantasies. If we just rely on inferences from history to explain everything, we are likely to wallow in speculative just-so stories and adopt stupid ideas like the Paleo diet. That's why there is this thing called medical science, which includes nutrition science. Real scientists, unlike broscientists, have to come up with testable hypotheses that might actually cure or treat disease. The very man who originated the idea of evolutionary medicine has said that he doesn't like the Paleo Physicians Network because doctors know very little about evolution. He said he "would like to distance evolutionary medicine from any direct application in the clinic until we can do some real trials." In other words, Mr. Wolf, your fantasies may please you and make you money, but they aren't medical science.

Let's listen to a guy who doesn't do a podcast or run a gym. Instead, Michael Brown's major qualification is that he has been at the forefront of research into heart disease for the last 30 years. What does he think we should know about diet and heart disease?

BROWN: So we can cure heart disease. And yet you ask, well, what’s the government doing about this? Why aren’t we all being urged to eat low-cholesterol, low-fat diets? There doesn’t seem to be any kind of campaign going on and I think that’s a real tragedy.

He's pretty clear, isn't he? This man is a legend in bioscience and yet I'll bet hardly anyone watching my videos has heard him speak about this. This dedicated and accomplished scientist is not heard above the din of pretenders. The fad diet salesmen have the loudest voices instead.

Doctors like Brown work tirelessly to find new ways to help patients. Enormous sums of money are poured into research to develop new drugs. Scientists around the world are up at all hours trying to produce breakthroughs. But is all this effort by the medical profession focused where it will have the greatest effect? One of the best weapons in their armamentarium against heart disease is statin drugs. And yet many patients can't be bothered to take their medication consistently. If people don't take their drugs, how effective can their drugs be?

Doctors focus on drug therapies because they don't believe that adequate lifestyle changes are realistic for most patients. Unfortunately, the data show that they are right. Behavioral counseling produces only modest improvements in the dietary habits of patients.

How do we address the health problems of humans when these problems and the best solutions for them depend upon the behavior of humans? Humans aren't consistent about taking their medications and they are resistant to lifestyle changes. What if there were a switch we could throw in people to get them to be deeply and personally dedicated to a heart-healthy lifestyle? I don't pretend to have all the answers, but I do have an idea that I think will help. What if part of the answer to non-communicable diseases doesn't even relate directly to medicine? What if one of the best ways to help a person to be healthier involves shifting his attitude about our world? What if one answer is to believe in something?

I think cultivating compassion for animals can make us healthier. People who think it's morally wrong to consume animals tend to be pretty consistent with their diets, and I've shown you that as a group, vegans and vegetarians are less fat and are less likely to develop diabetes and heart disease. As strange as this may sound, you can make choices every day out of your love for animals and be in alignment with the best and most current science in nutrition at the same time. In a way, the Paleo diet idea gives us a fresh perspective from which to view our treatment of animals. We humans have progressed beyond the primitive values of our ancestors. Our relationship with animals should reflect that.

Historically we have gotten into trouble when we divide and labels ourselves, and just think of someone different as the other. Loren Cordain wants to believe that at some point in the past we just turned into a whole new species called homo sapiens. We began and left them behind. There is a clear separation.

Yet Darwin said, "Certainly no clear line of demarcation has as yet been drawn between species and sub-species." And, "These differences blend into each other by an insensible series..." Our development has come about ever so gradually, and this fact should cause us to rethink our connectedness to other species. "Homo sapiens" is just a label we made up. Sometimes our labels limit our thinking.

We have come so far from the other end of that imaginary football field. Who would want to go backward to the other side? Who would want this for their children?

Could there be a more retrograde understanding of our place in the world than Paleo? That seems to be the furthest a reactionary could possibly retreat into the past for his inspiration.

Paleo romanticizes a past that was blanketed in the darkness of a profound ignorance like we can scarcely imagine.

Darwin himself observed the human behaviors that preceded the introduction of civilization and reason. He attested to the practice of human sacrifice and intractable bloody warfare. What if our supposedly primal existence was far more savage and brutal?

It has been argued that the first humans who left Africa to inhabit Eurasia were culturally violent. We would not share a common sense of morality with these people. Their world would be a living nightmare for us.

Within a single paragraph in this paper describing how primitive tribes neglected and killed female infants, Loren Cordain's name appears as a reference. These hunter cultures he fetishizes assigned women a lower value. If you believed that infanticide is authentically Paleo, would that make it ok?

If you knew that incest and child sexual abuse were commonly practiced by hunter gatherers, would you decide that that behavior was programmed into your genome?

As offensive as that will be to you, consider that those are examples of how children could be treated within their own tribes. Steven Pinker's The Better Angels of Our Nature describes the high rates of violence among humans living in non-state societies. Primitive humans were capable of astounding barbarism, even toward children, as you will understand if you read this slide. Pinker’s abundant descriptions of the violence of the past will clarify for you on which end of the Paleo football field is the better place to stand. Even more recent than agriculture is the civilized world’s respect for the dignity and value of all human life. The brutality of the past has been left behind for good, and there is no gimmicky descriptor for it like “Paleo” that can make it more attractive. We are gradually figuring out what is wrong with violence toward humans. At some point we’ll realize that violence toward animals is wrong, too.

Thankfully, we are now more morally developed creatures thanks to civilization. It makes no sense for us to take our lifestyle cues from a concept - evolution - that has nothing to do with morality. Dr. Pinker reminds us that evolution is inherently cruel and pitiless. It is replete with the most extreme violence.

Perhaps Katharine Hepburn's old line is the best response of all to Paleo. She said, "Nature is what we are put in this world to rise above."

Do you remember how we saw that human populations stagnated for eons before the adoption of agriculture and the formation of governed societies? One of the ways population sizes would have been limited was through violence and warfare.

We live in a much less violent time, and we are much healthier now. Our lifespans are far longer. Hunter gatherers have a mortality profile that is similar to that of wild chimpanzees. They experience death rates many times greater than we see in modern peaceful societies.

For this reason, these researchers said that an age of about 72 years old for culturally modern people is comparable to 30 years old among hunter gatherers. These are the points at which probability of death are the same in each group. Yet the hunter gatherers are the models upon which the Paleo fad is based.

There can be no doubt that humans intuitively associate meat with masculinity. The reasons for this must be primitive and instinctual.

Paleo seems perfectly positioned to tap into this built-in, unthinking bias. Men who are overly concerned with displaying their masculinity will be drawn to the meat in Paleo as well as its rejection of processed foods. Vegetarians are more likely to be women. Food has always been a hard-wired preoccupation for us. Some of our reactions to it are automatic and irrational.

Therefore, it should not be surprising that the values of vegetarianism sometimes elicit mindless responses from hypermasculine and ignorant men. Their regressive values clash with progressive ideas that arise around them, and they react defensively.

If a man were to consider the possible side effects of eating the low carb way, he might reconsider his association of meaty diets with masculinity.

Even statin drugs might be better associated with masculinity than low carb diets. Erectile dysfunction has been improved with the use of cholesterol-lowering drugs.

And LDL over 120 was associated more strongly than any other factor with erectile dysfunction in this study, with the exception of obesity. Any diet that raises LDL had better improve your sense of masculinity in other ways because it probably won't do you any favors in this department.

We live in an entirely different world than that of our ancient ancestors. Let's not allow fantasies to prevent us from accepting our present reality. Meat eating threatens our environment in many ways. 43% of the land of this planet is already committed to agriculture and development. We are pushing our planet toward a potential state shift that could result in ecological disaster.

Animal agriculture takes up more land mass than development, amounting to one-third of all land. It uses two-thirds of all the land utilized by agricultural.

Meat consumption is inherently wasteful and inefficient, so it worsens our environmental problems.

Land use is just one major problem with meat production. As meat consumption rises, so will water use, water that the world cannot spare.

Fortunately, we in the US have recently begun to bend downward the line on meat consumption, but meat eating is predicted to increase worldwide well into the future.

Meat eating also generates waste that harms the environment. A typical cow produces almost 80 pounds of manure a day. This waste is filled with hormones and other contaminants.

These wastes also promote the accelerated evolution of disease-causing and antibiotic-resisting microbes.

I showed you that meat-eating wastes land resources, yet despite that, some would suggest we should convert even more land to animal food production in order to raise grass-fed beef. This will only worsen some of the present problems with beef production, like deforestation...

And climate change caused by greenhouse gases. Pasture-grazing of beef actually worsens this problem.

The pasture-raising of livestock will not be a part of any serious solution because this practice requires an especially large ecological footprint. We shouldn't pretend that converting more land to food production is a new way of protecting nature. If we care about the environment we should be looking for ways to leave wild areas alone, free of human corruption.

Grass-fed beef is less efficient than conventional beef because animals fed this way do not grow as fast. Less meat is produced from them, yet they produce more methane emissions.

They also are more likely to have toxins concentrated in their tissues via bioaccumulation.

I have seen it claimed by Joel Salatin that cows do not affect methane emissions one way or the other. He offers no reference for this and I have not been able to verify this statement. He says that wetlands emit much more methane than livestock, as if this is a defense of livestock.

It seems to me that the production of methane in livestock is fairly well understood, with bacteria acting under the anaerobic conditions of the animal's rumen to generate the methane. This is called enteric fermentation.

Meanwhile, wetlands perform very valuable services for both humans and the animals that live in them. Try to figure out Salatin's point in that comment. What is he saying? That we should get rid of wetlands before we get rid of cows? Or that methane and global warming don't matter? Or is he just trying to confuse the issues the way the cholesterol deniers and low carbers do? If I were trying to protect the antiquated practice of eating animals, I guess I would try to change the subject, too.

Methane emissions are just one part of the greenhouse gas story. Along with livestock comes deforestation and the loss of carbon sinks that represents.

Whether it comes from the feedlot or the pasture, beef is an inefficient way to produce food if you are at all interested in greenhouse gas emissions...

Even if you consider the argument that cattle convert otherwise inedible biomass into human food. Biomass should not by default be equated with potential human food. Rather than searching for ways to exploit and ruin more ecosystems, we should try to more efficiently feed ourselves with less land.

Look past the truthiness of grass-fed for a moment at the real world around you, and you might notice that droughts in the US have left most pasture and rangeland in poor or very poor condition. This will drive up the cost of meat. As weather becomes more extreme into the future, an already unstable source of food will probably become even less stable. Grass-fed beef is no answer to this.

The current fascination with grass-fed beef seems to me to be derived from locavorism. This famous study showed us that from a greenhouse gas perspective, locavorism doesn't have much to offer, either.

The health claims for grass fed also seem to me to be totally speculative. Tiny changes in the amounts of certain fatty acids or vitamin E are supposed to compensate for the other disease-causing properties of beef. If this were true, why when I look at the countries that rely on pastured beef the most do I still see evidence of an association between beef consumption and disease? In Uruguay and Argentina, the land of the gaucho, we see some of the highest rates of breast and colon cancer in the world.

Why do Japanese immigrants to Brazil have an increased risk of stomach cancer when they eat more beef, which is typically grass-fed there? Fruit consumption was associated with a lower rate of stomach cancer for these same people. Fruit is easier on the environment and it doesn't promote disease. But to an ignorant person struggling with weight control problems, fruit's a carb, so fruit must be bad for you.

Why in Australia is fresh red meat associated with an increased risk of rectal cancer? Aren't they mostly grazing their cattle?

By the way, environmentalists, cattle are not native to Australia.

Beef production now stretches over nearly one-half of the land surface of Australia. When cattle were brought there, they brought harm to native ecosystems. The land use problems of grass-fed beef are apparent there.

Along with those cattle have come non-native species of vegetation for them to eat and these have aggressively displaced native species of vegetation. In Australia as anywhere, the climate is not stable and in times of drought, grains are fed to cattle. This is because people won't reduce their meat consumption in times of drought unless there is a clear price spike that would cause a change in eating habits. This illustrates how the needs of the commercial market for beef come first, not a commitment to grass-fed. When was the last time you heard of a Paleo dieter going hungry or eating just potatoes because his local area was in the midst of a draught?

As we often see with invasive species, cattle have displaced native wildlife, causing what is here called "a significant biodiversity extinction debt, the full impact of which will not become apparent for 50-100 years." If you are going to eat beef, be clear that you are not doing this for the good of the planet.

We often hear about how well-managed the water use is in the Australian beef industry, but the deforestation associated with beef may be causing Australia's climate to become hotter and drier. In the long run, even in Australia, beef is probably harmful to fresh water resources.

Grass-fed beef is falsely offered as a solution to the environmental harm of beef. To the contrary, it will not displace much of the global demand for beef that is produced using conventional intensive methods. There is a simple reason for this. Grass-fed beef is a luxury product. Look at this huge difference in price I found comparing beef at two grocery stores near where I live. Most people simply don't have the money to squandered on this. The money saved on conventional beef will be more intelligently spent on the pressing economic needs of families rather than as a membership fee to join the vanity meat trend.

Meanwhile, lentils are far healthier and far cheaper than any kind of beef. The adoption of plant-based diets on a large scale is totally realistic, especially when people realize that eating this way actually makes you richer. A penny saved is a penny earned. A whole food vegan diet will keep more money in your pocket in the short term. Over the long term it should save society money, too, since you'll be more likely to maintain a healthy body weight and clean arteries.

Because grass-fed beef is a luxury product, industrial livestock production is growing six times faster than grass fed. This is what happens when such a huge cost differential exists between similar products, and this is why I think anyone who says grass-fed is the answer to any big problems is dreaming. The market has spoken. People will seek lower cost food. This will not change.

It is predicted that as peak oil is reached, the cost problems with beef will become even worse.

Other forms of meat aren't better for the environment than plant foods, either. Take fish for example. 40% of marine catches are classified as by-catch - unwanted marine species caught at the same time that the wanted species are caught. These fish are usually thrown back into the water dead and dying, discarded and forgotten.

An example of the extreme waste and irresponsibility of marine food harvesting is shrimping in Argentina, where most of the life dragged onto a boat is by-catch. Only one seventh of the usual catch is shrimp. The next time you eat shrimp, you might consider all the other marine species killed for you that do not appear on your plate, as Jonathan Safran Foer has suggested in his book Eating Animals.

This paper notes that those figures should be regarded as indicative of only the minimum estimates of the amounts of by-catch that are now being wasted.

Paleo dieters apparently think that chicken, of all things, is a bird they evolved to eat. Actually, they are designed by us just to be put in our mouths, and there's nothing Paleolithic about that. Today's poultry are not the results of natural selection. They are human-created genetic freaks. Today's birds sometimes flip over and die spontaneously in what is termed "sudden death syndrome," and the cause of this is likely genetic.

A similar sudden cause of death among chickens is called ascites. That kills them through oxygen deprivation. This strange type of death is probably a result of our manipulations of them.

Chickens today are extremely different than they were even one hundred years ago. Sudden death syndrome and ascites should give the Paleo dieter a clue that their chickens are distorted modern creations that have nothing to do with the world of Paleolithic man.

It seems about right that retrograde concepts like Paleo and meat-based diets are associated with a certain strain of cultural conservatism. This article by Vasile Stanescu makes for interesting reading on this topic. I suggest you look this article up.

Like those quotes you saw from Robb Wolf, it is sometimes a bit jarring how openly reactionary some of the icons of modern meat promotion can be. Here is Joel Salatin again, quoted in The Omnivore's Dilemma, responding to a question about how New York City might fit into his vision of a locavore food economy. He said, "Why do we have a New York City? What good is it?" That's just a little ironic considering where the publisher of this book is located. How could any intelligent person say such a thing? Does this question even deserve an answer? Mr. Salatin, cities are the places where we generate most of our culture and science and commerce. I don't expect you to understand.

It's an odd thing to say, but in making these videos about low-carb, Paleo, and the myths surrounding meat, I have often felt like I am in the position of defending human progress. There is apparently an inclination even among the well-educated to idealize a fictional past, as if they would rather live in some bygone era. This nostalgia can only be sustained with a selective memory and a narrow focus. The "good old days" had awful problems that we are lucky to have avoided by the accident of the timing of our births. When we contemplate that slavery and discrimination were found to be acceptable in the relatively recent past, we might ask ourselves what institution we uncritically accept today that will be regarded with disgust by later generations. I submit to you that the unnecessary abuse and killing of animals for food is an excellent candidate for just such an immoral institution.

Why would any modern intellectual romanticize a savage past? Here is an old article by Jared Diamond. In it he argued that the adoption of agriculture was the worst mistake in the history of the human race. He blamed it for the creation of kings and classes of social parasites, as if he thinks we are still in the middle of the French revolution. He says that it is inconceivable that a Bushman could starve the way the Irish did during the potato famine, apparently without understanding that a mass famine was only possible in Ireland because the potato had nourished the Irish well enough to support a large population. You don't hear about famines among hunter gatherers because they are small in number, scattered, and disconnected from the civilized world. An historic large-scale famine is not possible within a tiny population.

Diamond wrote some truly silly things. His argument against those who would say that civilization allowed for such artistic triumphs as Bach's B-Minor Mass is that great art is a product of free time and hunter gatherers have free time. Yes, Dr. Diamond, but they don't have the B-Minor Mass, do they? He says primitives produced paintings and sculptures, but he doesn't seem to have noticed that civilization has produced far more, and it has produced more and better art in practically any other medium that you can think of. And it is not only art that was made possible by agriculture, but science. Completely blind to this fact, Diamond later argues that archaeology is not a mere luxury. No, he says, archaeology is something so useful, it has led to the ridiculous ideas he put into this article. Did hunter gatherers have archaeology, Dr. Diamond? I don't think so. Does it not follow that there would have been no Jared Diamond had there been no agriculture? How can he not have realized this?

Diamond, like the Paleo gurus, is very selective about where he places his attention. He even makes reference to hunter gatherer infanticide in his article, but it is in passing and without judgment. I guess that doesn't offend him the way agriculture does.

He wrote, "Suppose that an archaeologist who had visited us from outer space were trying to explain human history to his fellow spacelings." He then gives us his version of the football field metaphor of the human race, except in this case the yard lines on a football field are instead the markings on a 24-hour analog clock. Civilization doesn't take hold inside the one-yard line in this version. Here it kicks in at six minutes before midnight. It's the same idea, though. This passage is absolutely comical to me! Dr. Diamond, let me ask you. That space-traveling archaeologist - in your head, is he a hunter gatherer? Was there no industrialized society back wherever he came from that built his spaceship for him? I can't believe he actually wrote that. He put no thought into that at all. Doesn't his clock metaphor actually put into perspective the cultural and intellectual stagnation that enshrouded humanity in ignorance for eons, which was only slowly and painstakingly removed by the heroes of science and reason once agriculture and the specialization of labor allowed us to pursue our own unique talents and dreams? Dr. Diamond's values, if he really believes in them, might lead him to some unconventional ideas about what would be in the best interest of society. Perhaps he would like to propose that the World Bank change its current mission of economic development. Instead, they should reverse course and look for a way to return us all to the Stone Age. Life was better then, wasn't it? No kings or social parasites, right? Mad Max, here we come!

Does Diamond not realize that his imaginary spacecraft presupposed a culture built upon an extreme specialization of labor, and that this very system can only exist where there is efficient agriculture? Does he not realize that his own labor as an academic is extremely specialized and useless in a hunter gatherer society? I wonder how he found time to earn his PhD if he was also running around with a basket and a spear looking for food while he was in school.

It is so hard for me to understand why a scholar would romanticize a time before scholarship. Who doesn't remember the teacher who taught us the best with gratitude?

Aren't the heroes of history those who shattered our self-serving delusions?

Didn't our greatest leaders make us more civilized?

Steven Pinker has pointed out how difficult it has been to speak honestly about the savagery of the past. Romantic notions of the natural state of man are preferable to the ugly truth for some. Apparently they would prefer that our history be sanitized.

I found a very good opinion piece that was published in 1975 in Harper's Magazine that relates to this bias against modern lifestyles and values. It was written by Samuel Florman and it is called "In Praise of Technology."

In it, Florman expressed his frustrations with the few intellectuals who argued that the world was a better place before it became industrialized.

He called those intellectuals anti-technologists and of them he said, "Their ideas are so obviously false, and yet so persuasive and widely accepted, that I fear for the common sense of us all." I know exactly how he felt.

He quoted Daniel Callahan, who said that "Man is by nature a technological animal." This is to me the salient quality of humanity from the perspective of evolution. We have been ever adaptable and curious. We constantly remake and reshape our world as we learn more. Callahan said, "we should recognize that when we speak of technology, this is another way of speaking about man himself in one of his manifestations." This is a profound truth. The advances we have made in the last 10,000 years are a part of us. There is no going back. Our progress has made us more human, because our desire for progress is what makes us human.

Florman said, "It is difficult not to be seduced by the anti-technologists' idyllic elegies for past cultures. We all are moved to reverie by talk of an arcadian golden age. But when we awaken from this reverie, we realize that the anti-technologists have diverted us with half-truths and distortions." Not much has changed, has it?

He concluded by saying of the anti-technology philosophy, "It is a hollow doctrine, the increasing popularity of which adds the dangers inherent in self-deception to all the other dangers we already face." We face dangers today as well, both to our own physical health as well as the health of the planet. We must look toward our future and not the past, and we must be able to distinguish reality from fairy tales.

This doesn't mean we should forget who we are and where we've come from. Maybe a lesson from evolution that can guide us into the future is a recognition that one of our more advanced characteristics as a species is our ability to feel empathy. Mammals must be able to sense and respond to the feelings of others. This is necessary to understand and address the needs of our newborns, who cannot communicate their needs to us with words. We have empathy because empathy is clearly adaptive.

Our worst moments happen when we ignore our impulse to feel for and care about others. We create barriers and divisions and we diminish the value of those not like us. We create ingroups and outgroups. We use labels. This is what happens in the mind of a racist.

Simon Baron-Cohen has written a wonderful book called The Science of Evil. In it, he proposes that what we call evil can best be understood scientifically as the absence of empathy. He says we all lie within a spectrum of capacities for empathy. Those who cannot feel empathy for others are said by Baron-Cohen to have zero degrees of empathy.

He has suggested the outlines of what he calls an empathy circuit in the brain. A pathological lack of empathy is caused by some type of dysfunction or disruption in the empathy circuit. He advocates treatment for those whose lack of empathy harms their ability to be productive members of society.

Baron-Cohen's idea that the lack of empathy represents an impairment of structures in the brain is gaining support. A student of evolution might take from this the view that the empathy circuit is a higher-level social function that is likely a sophisticated result of natural selection, and therefore conclude that to lack empathy is be less evolved, less whole, and less human.

In The Better Angels of Our Nature, Steven Pinker argues that over human history and even through the 20th Century there has been an unmistakable reduction in violence. Over time we have gradually found better ways of resolving our differences and we have come to be more concerned for the suffering of others.

Pinker is quite right to include a section in his book about our treatment of animals, which in many ways has improved dramatically, even quite recently.

And yet violence against animals persists on a massive industrial scale worldwide. How can this be? It is because this violence is hidden from our sight. It is even mostly out of the sight of the workers who we pay to carry out that violence on our behalf. The stages of slaughter are segmented and isolated. It is this detachment from reality that allows this violence to continue.

We can't look at these horrors because we have empathy. We can relate to animals and they can relate to us.

If we could see it with our own eyes, most of us would understand that the practice of killing animals for food is wrong. It is unnecessary. It is an injustice.

MLK understood that for humanity to advance, we must expand our circles of empathy. It is time for us to remove another barrier built from labels and divisions and extend our consideration to those who are innocent and cannot speak.

An official at the NIH wrote a piece in 1953 called "Nutrition – Past and Future." He took stock of the triumphs of nutrition science up to that point in addressing deficiency diseases and he anticipated the need for nutrition science to answer the new challenges from non-communicable diseases. Sixty years later, it is time to take stock of our place in history again. If we care for the environment, if we seek less violence, and if we desire better health, we must rise above our old ways. The future of nutrition is now inseparable from the future of humanity.