Welcome to Earth, Population: 7 Billion

This month, the global population will surpass 7 billion people, for the first time in history. Predictably, this milestone has sparked a discussion of overpopulation and sustainability. Pessimists are quick to point to the historical trend. Two thousand years ago, the global population was a mere 200 million people. Even by 1900, there were only 1.6 billion of us. But during the 20^th century, population growth exploded as modern medicine dramatically increased life expectancies all across the world. Even people in the shortest-lived countries today (Afghanistan and Zimbabwe) live longer than those in the longest-lived countries did in 1800 (United Kingdom and Netherlands).

The unfortunate side effect of that amazing record of progress has been an ever-increasing population, consuming more and more resources from our planet. Many have questioned how long this can continue. As early as 1798, Thomas Malthus argued that growth in population was outstripping growth in the food supply, and this would inevitably result in widespread famine. In 1968, Paul Ehrlich wrote The Population Bomb, which predicted that overpopulation would soon cause mass starvation, destroy the environment, and lead to widespread war.

So far these predictions have failed to materialize, and it is unlikely that they ever will. Concerns of global overpopulation are overblown. There is plenty of room for everyone; we could fit the entire world’s population into the state of Texas, and the population density would be no greater than New York City. On the question of food security, the Malthusian predictions have always failed to take into account technological development. When Malthus made his original prediction, he completely overlooked the Industrial Revolution that was beginning to unfold around him, making the production of food much more efficient. When Ehrlich did the same, he overlooked both the Green Revolution that increased the production of food threefold, and the invention of new birth control technologies which reduced the rate of growth in the population.

In fact, population growth peaked in 1968, just as The Population Bomb was hitting bookshelves. Although it has not yet stabilized, the rate of growth continues to decline. Some parts of the world are already losing people; the fertility rates in Europe, Russia, and East Asia are well below the replacement rate. The United Nations projects that the global population will plateau by the end of this century, between 10 and 15 billion people.

Even the upper end of the UN’s projection is not unsustainable; if we have 15 billion people by the end of this century, we will easily be able to feed them all, with plenty of food to spare. The population doomsayers will continue to be wrong for the same reason that Malthus and Ehrlich were wrong: they ignore technological developments that allow the production of much more food. The coming Genomic Revolution will play a huge role in this process. Not only will it soon be possible to genetically engineer crops that produce a much higher yield in a given amount of space, it will also be possible to breed crops that can grow in much harsher climates than is currently possible, allowing for the widespread production of crops in parts of the world that were previously considered off-limits. The drought-ravaged Sahel Zone of Africa could one day be a breadbasket. Cold climates like Canada and Russia may one day be able to grow coffee.

Additionally, the development of in vitro meat production will soon mean that it is no longer necessary to raise large herds of livestock when meat can be more efficiently grown in a laboratory. This will free up a huge amount of the earth’s farmland and fresh water, which would otherwise be required to feed the animals. These technological developments – as well as others which may not even be anticipated yet – will undoubtedly allow us to continue feeding our growing global society.

Although global overpopulation is not a problem, the problems of specific regions of the world should not be minimized. South Asia is the hardest hit by overpopulation. India has 1.2 billion people crammed into an area one-third the size of the United States. Bangladesh has 150 million (half the population of the US) packed in an area smaller than Florida. In both of these cases, the vast majority of people live in crushing poverty, with some of the highest rates of malnourishment anywhere in the world. But even here, there is some good news. Both India and Bangladesh have taken steps to get their fertility rates under control, and now their fertility rates are only slightly above the replacement rate of 2.1 children per woman. The era of rapid population growth is drawing to a close for South Asia, although it will still take several decades before it levels off completely.

Many Sub-Saharan African countries have a demographic problem as well, although the nature of the problem is different from South Asia’s problem. With a few exceptions, Africa is not particularly densely populated. Some UN officials and developmental economists have even gone so far as to argue that many parts of Sub-Saharan Africa are underpopulated. I think that’s a bit of an exaggeration for a region of the world that cannot currently feed itself, but there is no denying that Africa’s population is nowhere nearly as densely populated as South Asia. India alone has more people than the entire African continent. Africa’s demographic problem is the rapid rate of growth in its population. Unlike India and Bangladesh, which have finally gotten their growth rates under control, many African nations still have fertility rates as shockingly high as 4 or more children per woman. In the case of Niger, the fastest-growing country in the world, women have 7.6 children on average. In other words, the problem facing many Sub-Saharan African nations is that their population is growing faster than their ability to provide for their people.

Can Africa’s demographic problem be solved? Of course. High fertility rates are closely linked to poverty. Families tend to have more children in societies where the opportunity cost of having kids is low, where children can assist with subsistence farming, and where infant mortality rates are high enough that having extra children provides a hedge against the tragic risk that some of them will not survive to adulthood. As Sub-Saharan African countries continue to develop their economies, these underlying problems will fade away just as they did in South Asia and Latin America, and fertility rates will drop. This issue has been widely studied by developmental economists, who have concluded that the best ways to reduce fertility rates are to ensure access to cheap birth control, improve education (especially for girls), and improve health care and nutrition for infants. Many African nations are making tremendous progress toward these goals, and are already seeing the dividends in reduced fertility rates.

So when our global population officially hits the 7 billion mark this week, remember to take the doomsayers with a grain of salt. Our planet is not overpopulated. At the present time, it is a localized problem for only a couple regions of the globe, and soon it will not be a problem at all. Our economic and technological development will see to that. There is plenty of room on our pale blue dot for more people.

The Future of Sleep: Entirely Optional

Why do we sleep? This seemingly simple question is one of the longest-standing unsolved mysteries in biology. As bizarre as it sounds, there is no obvious reason why we are inactive for a third of our lives. National Geographic and TIME have both tackled this subject to explain some of the most predominant theories, but the bottom line is that no one really knows. Some scientists believe that sleep restores some as-of-yet-undiscovered substance in our brains, which is depleted while we are awake…or that it removes some as-of-yet-undiscovered substance that accumulates while we are awake. Some observers have noted that getting REM sleep is necessary for our learning of new tasks. Although this is true, it fails to explain how sleep helps us learn or why it is necessary for us to be dormant during this process. Others have theorized that the reason that mammals sleep so much compared to other animals is an artifact from the age of the dinosaurs: At the time, most mammals were nocturnal. Perhaps sleep forced mammals to keep quiet during the day, to avoid becoming dinner for a hungry Tyrannosaurus.

Last year, biologists identified a rare gene which allows people to feel rejuvenated after only a few hours of sleep, indicating that it should be possible – at least in theory – to modify the amount of sleep we need in the near future. As the Genomic Revolution picks up in the next year or two, there will undoubtedly be many other genes identified that govern our sleep processes. Understanding them may unlock the key to understanding sleep.

Meanwhile, neurologists are making progress in understanding how sleep affects our brain. As electroencephalograms become more and more obsolete, scientists are gaining access to new ways to monitor our brain activity. Improved neural scans should allow scientists to pinpoint which areas of the brain are most affected by sleep, and how.

Perhaps soon we will understand the nature of sleep. Is it vital for our survival in a way that we don’t understand? Or is it simply a relic of our evolutionary past, with no useful purpose? Understanding sleep is the first step to conquering it. Is it possible that we could develop safe medication to mimic the benefits of sleep, allowing us to remain conscious for 24 hours per day, without the nasty side effects of caffeine or other drugs? This would change our world profoundly. We would essentially be living 50% longer by squeezing an extra eight hours out of our days. People could earn much more money by working more hours without sacrificing their leisure time, or alternatively, they could have much more leisure time without sacrificing their career.

Although some people often claim to enjoy sleep, I think most people would prefer to do without it, if we had the option. I have difficulty believing that anyone could truly enjoy something that they aren’t even aware they are doing. For most of us, our “love of sleep” is really “dislike of waking up.” If we could invent a safe way to remain constantly awake while still reaping whatever benefits we get from sleep, most of us would jump at the opportunity.

PREDICTIONS:
By 2030 – Scientists have a basic understanding of the reasons (if any) that we sleep, as well as why it evolved in the first place.
By 2050 – Medication exists that makes sleeping optional, providing people with any benefits of sleep without the need to actually do so, and without any nasty side effects.

Black Swan Events: Bioterrorism

The Genomic Revolution is a double-edged sword. As I mentioned previously, the benefits will be enormous. Genomics will allow us to have personalized, preventative health care, instead of mass-market sick care. However, there is also a ghastly dark side to the Genomic Revolution. We will soon face the truly horrifying prospect of bioterror (or bioerror.) When any college student has access to pathogens and the capability to modify them to make them even more virulent or transmissible, someone almost certainly will.

Within a few years, the genomes of nearly all human pathogens will be publicly available. This will be necessary in order to better understand these diseases and develop cures. However, those who wish to use this information to commit acts of mass murder will have access to it as well. Some diseases may not require very much modification to become even more deadly. The 1918 Spanish flu pandemic, which killed more people than World War I, is very genetically similar to many of the strains of flu that are still circulating to this day. Soon it will be possible for an individual to create a virulent flu strain like the Spanish flu by genetically modifying other strains.

Since genomics is essentially an information technology, it is possible to swap genes from one species into another. This is what allows agronomists to copy the cold-resistant genes of Arctic fish and paste them into tomatoes (in theory.) However, the same principle could be used by bioterrorists to create a Frankenstein’s monster, combining the worst traits of many diseases. Imagine an illness with the virulence of ebola, the transmissibility of the common cold, and the evolutionary adaptability of HIV. Such a disease is the stuff that nightmares (or B-movies) are made of. Yet it will eventually be possible for malevolent individuals or groups to create them.

If a manmade disease was sufficiently different from anything found in nature, it could prove devastating. We humans have had a chance to evolve alongside influenza, the plague, malaria, and other naturally-occurring afflictions. People alive today are mostly descended from the hearty individuals who survived earlier strains of these diseases. But we would not have evolved such immunities to manmade diseases. Just as the vast majority of Native Americans were decimated by European diseases to which they had no immunity in the 16th century, we could face the same prospect with manmade superplagues.

Fortunately, we have a defensive weapon in our arsenal that the 16th century Native Americans did not have. Just as genomics can create such frightening diseases, it holds the potential to cure them. Within a few years, it will be possible to sequence a genome in a couple hours. As our understanding of how genes work continues to grow, it will take less and less time to understand the genomes we sequence. Assuming that bureaucratic procedures were waived to combat a public health emergency, a cure for a manmade disease could be on the market almost as quickly as software antivirus programs are patched when new threats are discovered. Soon, naturally-occurring diseases could be a mere minor annoyance. The real public health danger could shift to the arms race between bioterrorists and scientists racing to cure their latest concoctions.

BLACK SWAN EVENTS:

By 2040 – A disease created or modified by humans has been released into the public. Probability: 90%

By 2040 – A disease created or modified by humans has killed at least 100,000 people. Probability: 75%

(I hesitated to even call bioterrorism a “Black Swan,” since that implies that the event is at least somewhat unlikely to occur. In my opinion, the danger of manmade diseases being released onto the public is not a question of if, but when and where. Since we cannot forecast this, it is unpredictable enough to be considered a Black Swan Event in my opinion.)

Blissful Genetic Ignorance - Will We Want to Know Our Genomes?

A couple readers have questioned me about the Genomic Revolution, wondering if people will truly want to know their genome even if they are able. As I mentioned in a previous post, people prefer to avoid thinking about things that seem both horrifying and inevitable. This is understandable. Would a person truly want to know that they are doomed to suffer from, say, Alzheimer’s disease or some other affliction that is commonly regarded as a fate worse than death?

While I can’t speak personally for anyone other than myself, I think that most people will ultimately prefer to know. As personal genomics becomes more commonplace, the mindset of blissful genetic ignorance will probably fade away. This wouldn’t be the first time that a new medical paradigm has changed public opinion about how much they should know. In a 1961 poll, 90% of US physicians surveyed said that they wouldn’t tell their patients if they had cancer. At the time, most doctors believed that patients would be better off not knowing since little could be done. But as cancer screening and treatment became more common in the subsequent decades, this mindset vanished almost entirely. Today it is hardly even imaginable that a doctor would not tell a patient if they had cancer.

There are so many advantages in knowing what conditions we are most at risk for. Ultimately, I think the knowledge of which of our unhealthy behaviors we most need to change (and which we can indulge in), and what prescriptions are most likely to be effective for our personal genome is simply more important than the unpleasant knowledge that we will eventually develop a certain condition. Practically everyone is at risk for something, and everyone accepts this. Would it really be so much worse for our psyches to know our specific risks instead of just a vague sense that we will develop something?

Please share your opinion. Would you want to know if you would eventually develop a disease?

The Future of Health Care - The End of Aging

What disease kills 100,000 people every day (usually after a prolonged period of pain and illness), affects nearly everyone, and kills about 90% of people in the industrialized world?

Aubrey de Grey, a renowned gerontologist, is on a quest to eliminate aging. The search for the fountain of youth has confounded humanity for millennia, but de Grey is on more solid scientific ground than most of his predecessors in this field. He has identified what he believes are the seven causes of biological aging – a list which has remained unchanged for the past 30 years – as well as the solutions for dealing with each cause. These solutions are not merely theoretical; they have all been demonstrated in labs, although most of them are many years away from being generally available.

Some casual observers may conclude that it is physically impossible to prevent aging since people have been trying and failing to do so for millennia. But the fact is that there are naturally-occurring examples of cells that do not age. Unfortunately, they’re called cancer cells, and tend to have the nasty side effect of killing people. Nevertheless, they do demonstrate the reality of cells that do not age.

Each cell in our body normally has an hourglass in it; the cell replicates as many times as it can, then commits suicide when the hourglass runs out of sand. But scientists have discovered how to add more sand to the hourglass. It’s an enzyme called telomerase that occurs at the end of DNA strands. Each time our cells divide, the DNA strands become frayed at the end, until eventually they are too unstable and self-destruct. For the discovery of telomerase in 1984 and subsequent analysis of how it relates to aging, three scientists were awarded the 2009 Nobel Prize in Medicine.

There is still a lot of research that needs to be done before it is possible to halt or reverse the aging process in humans. De Grey’s organizations, the SENS Foundation and the Methuselah Foundation, are currently testing life-extension therapies on mice. The Methuselah Foundation offers the MPrize: a reward of up to $4 million to anyone who can extend the lifespan of mice to record-breaking lengths. The goal is to eventually apply this knowledge to increase the human lifespan.

De Grey is not interested in extending the portion of life in which people are old, frail, and sick. His goal is to extend the healthy portion of life, and ultimately to prevent people from ever growing old at all…and reversing the aging process for those who are already elderly. This is not pie-in-the-sky immortality, as it won’t eliminate all causes of death. It would, however, offer the possibility of lifespans of indefinite length. De Grey has explained the concept as the “Longevity Escape Velocity.” Over the past century, medicine has done an excellent job preventing people from dying at young ages, but very little to prevent aging or increase the maximum human lifespan. At the present, medicine is progressing relatively slowly, adding a few weeks to our lifespan every year. When the Genomic Revolution picks up pace within the next few years, it is likely that this will be increased to a few months every year. De Grey hopes that eventually we can attack the root causes of aging itself to add more than one year to the human lifespan every year. He believes that the first person to reach age 1,000 is alive today…and is probably only about ten years younger than the first person to live to age 150.

The concepts of aging and old age are so ingrained in our mindset that we tend to not even think about them. Like anything that is both horrifying and seemingly inevitable, we have a remarkable ability to push aging out of our minds, or even to go through mental contortions to rationalize it as a good thing. Virtually all major life decisions we make – what career to pursue, how much of our money to save, how much risk to take, who to marry, how many children to have, when to retire, what our religious beliefs are, if or when we should go to college – are ultimately premised on the assumption that we will grow old and die, probably between ages 70 and 100. But what if this ceases to be the case? There is almost nothing that would alter our lifestyles, worldviews, beliefs, and culture as profoundly as the end of aging and the mindset that accompanies it.

Modern biology has already discovered theoretical solutions to all of the causes of aging; it is now a matter of applying them and developing solutions that work for human beings.

(The SENS Foundation and the Methuselah Foundation are non-profit organizations under US law. All donations are tax-deductible. If you have some money to donate, these organizations are helping to solve the single worst disease threatening humanity.)

PREDICTIONS:
By 2045 – The aging process has been halted, for all intents and purposes. People no longer grow old beyond their peak healthy age, between 18 and 25.
By 2060 – It is possible to reverse existing damage from the aging process. It is no longer possible to estimate an adult’s chronological age merely by looking at them. Diseases of old age have, for the most part, ceased to be a problem.

Genome sequencing? There's an app for that.

Richard Dawkins talking about the Genomic Revolution.

I think we'll look back on 2010-2011 as the tipping point for the Genomic Revolution, just as we look back on 1993-1994 as the tipping point for the World Wide Web...and the Genomic Revolution will be every bit as transformational as the World Wide Web, if not moreso.

The Future of Health Care - The Genomic Revolution

For the first time in decades, we are due for a completely transformational change in health care. We are on the cusp of the Genomic Revolution, and we will start seeing the earliest results in the immediate future. Personal genomics – the practice of tailoring prescriptions, treatments, and lifestyle choices to an individual based on their genes – will soon depose the old paradigm of medicine. No longer will doctors merely give patients the drugs with the highest chance of success; they will be able to predict whether or not the drug will be effective for a specific person. No longer will patients try to base their diet and exercise habits on generic recommendations of what is healthy and what is not; instead, they can determine the healthiest lifestyle for their genetic makeup specifically. Health care will become mostly preventative, rather than reactive.

Why now? What is the driving force behind this paradigm shift? For the first time in human history, we have enough computing power to cheaply and quickly sequence the human genome. In the very near future, nearly everyone will have access to their entire DNA code, which they can carry on their smartphones. When Craig Venter became the first person to have his genome sequenced in 2000 as part of the Human Genome Project, it cost $3 billion and took thirteen years. When James Watson had his genome sequenced in 2007, it cost $2 million and took two months. Today, sequencing a human genome costs about $6,000 and takes a couple weeks. Within the next year, it is very likely that companies will offer genome sequencing for less than $1,000. Some observers view the $1,000 mark as a tipping point: the point at which average people can afford the service, and at which health insurers may start covering it. And after we have $1,000 genomes, $1 genomes won’t be far behind. Let’s not forget that the cost has dropped nearly a thousandfold in the last three years. Fast-forward a few more years, and it is conceivable that the cost of genome sequencing will be essentially nothing. I envision a day in the not-too-distant future when Walgreens and CVS will have self-service genome sequencing machines, as quick, cheap, and user-friendly as self-service photo machines.

Of course, merely knowing one's genetic code is worthless without knowing how to interpret it. While biologists have identified thousands of disease markers, there is vastly more that we don’t know about our genetic code. Some services available now, such as Google-funded 23AndMe, can test DNA to determine one’s predisposition to a narrow range of diseases, but this is only the tip of the iceberg of what is possible. As the cost of genome sequencing approaches zero, nearly everyone will have it done. As the total number of genomes grows from thousands to millions to billions, scientists will have a treasure trove of data to analyze diseases and patient responses to medication. A machine called a microarray allows scientists to compare different DNA sequences and search for correlations. As more and more human genomes are available to be analyzed, patterns will become more evident and it will become much easier to unearth the specific genes associated with certain diseases. Patients who know the diseases for which they are at risk will be able to modify their lifestyle to prevent them from arising.

Those who are unlucky enough to get a disease in spite of (or because of) their lifestyle will have access to much more robust treatments than those currently available. By pinpointing the genetic location of a particular disease, scientists will be able to understand what caused the disease and how it can be reversed. Think of our genetic code like a computer program: Understanding the cause and location of the bugs will enable us to fix them. In the slightly more distant future, it will be possible to directly repair defective genes, such as those that cause cancer, through genetic therapy.

The next ten years will be the most transformative decade in human history for medicine, as we finally unlock the secrets of our genetic code which have been a mystery since the dawn of humanity. The things I have described here are by no means a comprehensive description of the benefits of the Genomic Revolution, and the new paradigm will not be without problems of its own. To be continued in another blog post…

PREDICTIONS:
By 2011 – At least one company offers genome sequencing for $1,000 or less
By 2014 – At least one company offers genome sequencing for $100 or less
By 2019 – Over half of all Americans have had their genomes sequenced
By 2021 – U.S. sales of personalized medicine (i.e. drugs tailored to the patient’s specific genetic profile) are greater than sales of non-personalized, mass-market medicine