The Root of the Matter Blog

How did we get so fat? Part 1

We have an obesity epidemic in our country, in case you hadn’t noticed. Over two thirds of American adults are overweight or obese. But why should we be concerned about this in the middle of a COVID pandemic? Here’s why. Obesity and its cousins diabetes and hypertension are three of those “comorbidities” that are causing people to die from COVID when they might have otherwise survived. Also, when this pandemic is over, the epidemic and its costs and consequences will still be with us.

I would like us to look hard at what are the causes of this epidemic and consider where some of the blame can be placed. This may help us in finding a way out. In this first part we will look at the scope of the problem and how we got here. In the second part next week we will look at the larger social context and some solutions.

It is difficult to place a starting date on the problem but if we put a stake in at about 1960, then we have had a problem for about 60 years. At that time about 13% of adults were considered obese. This would be a body mass index, a ratio of weight to height, over 30. By 2018, it is now about 42% of Americans in that category and about 30% in the overweight groups with a BMI between 25 and 30. As a real-life example, for a person 5’8” tall, obesity starts at 197 lbs by this definition. America has seen a 3-fold increase in this category in the past 60 years. Childhood obesity has also risen. For children above 6 years old, since the early 1960s the obesity rate has risen from about 4% to nearly 20%.

Obesity is not evenly spread. About 50% of Blacks are obese; 42% of Whites are obese, 45% of Hispanics, and 17% of Asian Americans are obese. We also vary by state, with Mississippi having about 70% more obesity than Colorado. A more complex picture of obesity emerges when considering sex and race. Among White men there is little difference in the obesity rate across income groups. But among Hispanic and Black men and especially among all races of women, obesity is more prevalent among poorer SES classes. The same basically holds true for education levels, with college educated women of all races having lower prevalence.

Obesity costs about $117 billion a year in direct and indirect costs, about half of that paid by taxpayers. About 100,000 deaths in the US per year can be attributed to obesity. The cost of obesity to our nation now exceeds that of smoking.

Dieting, as many of us know, is a lost cause, unless you are in the dieting business. The global market for dieting products and services has grown to about $255 billion this year. Of course, this includes the thousands of diet books available, diet foods that one can purchase, drugs one can take, supplements that are available, groups one can pay to join, and counseling one can receive. And probably over two thirds of folks who successfully lose weight will regain it in five years.

History

So, we Americans are in quite a pickle, but it wasn’t always this way. We are familiar with the sin of gluttony. Back when sins were sins this was serious business. In certain societies obesity and gluttony were associated. This was not true for every society and every era. In Europe when class structure was more rigidly in place, it was expected that higher classes would be heavier and have fairer skin. Both of these traits were associated with not being in the sun working all day and having generous quantities of rich foods. Famous paintings of nudes from the time show women that would be considered rather large by today’s anorexic standards. And in some non-European cultures, these perceptions of overweight and obesity in women still persist, including certain Arab cultures, in parts of Africa, and in certain Pacific Island cultures.

How did we get here? You may be familiar with the concept of calories in and calories out. If more calories go in as food than come out as physical activity, then weight is gained. While there is indeed truth in this thermodynamic balance, there are factors inside and outside the body that have driven the dramatic increase in obesity over the last 60 years. As we parse out apparent causes, we have to think about things that have actually changed over that time period.

Causes

Let’s start with two examples.

Genes. We are now in the genomics age with the full library of the human genome and we have been able to identify at least 76 genes whose mutations can contribute to obesity. So, are genes responsible for the obesity epidemic? We humans have had basically the same genes for the past 10,000 years or so including these various obese-prone mutations, and yet we are only getting fluffier in the past century. While we can show that folks with more of these mutations have a higher risk of obesity, there are still plenty of folks with lots of obese mutations that are normal weight. These mutations might best be called obesity susceptibility mutations. They only turn on the fat when they meet various internal cues that are facilitated by external factors like lifestyle and environment.

My second example- diet. Has this changed over 60 years? Yes, in fact it has. Caloric intake has increased from 2880 kcal in 1961 to 3600 kcal in 2013, a 24% increase. This corresponds to roughly 100 kcal of meat, 100 kcal of sugar, 175 kcal of starchy foods, and 400 kcal of vegetable oil used in snacks and other prepared foods.

Most food in 1960 was home cooked, had less sugar and salt, and few people ate out, especially at fast food restaurants. Many families ate together. Today, families rarely eat together, often eat out, and often eat pre-packaged foods and a lot more snack foods and sugary drinks. Where we eat, what we eat, and how we eat have all changed. Is it any surprise that our weights have changed?

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Then there are factors in our environment that have changed. Our pharmacies are dispensing many more diabetes medicines, antidepressants, antipsychotics, and antihypertensives. Many of these are known to increase weight, not only by their direct effect but also because they put us in better health and better moods.

We are sleeping less than in the past, between one and two hours a night and with much more shift work. Epidemiologic and experimental work has shown that sleep deprivation adds pounds.

We are exposed to more endocrine disruptors. These are chemicals that benefit us in some way but have been shown to have untoward effects on health including weight gain. These include flame retardant polybrominated diphenyl ether (PBDE), and the plasticizer bisphenol A (BPA) and phthalates, DEET the bug repellent, and dioxins.

Air conditioning has increased since the 1960s. In a counterintuitive way, bringing our homes to a steady 70 degrees or so year-round actually burns less calories.

We all have more screen time than in the past. In the 60s it was a grainy black and white screen with 13 channels if you were lucky. Now we have multiple devices for multiple purposes. Our children spend 5-7 hours a day watching screens big and small. Research has shown a clear link with obesity. While watching screens, we are all less likely to be paying attention to the snacking we are doing. We call this mindless eating. We are also clearly not outdoors being active. We are not eating home cooked meals with the family. Kids see more food commercials and tend to have less sleep and more disrupted sleep.

Now for our diets. Since 1950 we have consumed about 18% less fiber. Since the early 1800s we have steadily increased our sugar intake by over a half a pound a year every year. We now consume about 120 lbs per year or about 1/3 lb per day. Most of this is in snacks and beverages. It is amazing to walk into a convenience store and see the huge array of drinks and snacks available.

This problem has come on us slowly. We can’t really remember a time when half the people we meet in the mall or on the street were too large to be healthy. We don’t think it is unusual to walk into a gas station/convenience store and find it wall-to-wall with junk food. Heck, when did gas stations and convenience stores first get married? When did the size of McDonald’s drinks start to creep up? We are surrounded by an obese culture that we are immune to. Next week we will talk about this culture, where it comes from and what to do about it.

Dermatology vs. Nutrition, the Case of Vitamin D

I went to my dermatologist last week for my yearly checkup, an experience almost as pleasant as my semiannual trip to the dentist. I got checked over and we had a distracting conversation while he did his thing. On the way out he gave me some paper instructions and an interesting flier that is the topic of this post. I have attached it below. It is titled SUNSCREEN RECOMMENDATIONS and has this recommendation, “Boone Dermatology Clinic recommends daily sunscreen use for all patients over the age of 6 months. We recommend a broad-spectrum sunscreen with a minimum of SPF30.” It is important to notice how inclusive this is: everyone over 6 months with no exceptions, broad spectrum for all wavelengths, a SPF30 so that it is a complete blockage, and daily use with no exception for season or weather or time of day. This apparently means all day. Here is my problem with this statement as a nutritionist. This pretty much guarantees that all their patients will be vitamin D deficient.

Here is what pretty much any textbook will tell you about vitamin D. We get most of it from the sun. It is called the sunshine vitamin for a reason and is barely even a vitamin in the usual sense. The same UV radiation that gives you sunburns allows you to make vitamin D in your skin. But any SPF greater than about 6 completely blocks vitamin D synthesis in the skin. We only get the right UV from the sun between about 10AM and 3PM. All latitudes north of about 35 degrees (think Atlanta, Georgia) is too far north to get sufficient vitamin D from our usual exposure to the sun. Most Americans get almost no vitamin D from the sun in the winter both because the sun is too low and because we are so covered up. Just imagine what this says about the vitamin D status of Canadians. About 15 minutes in the full summer sun with bare arms and face will give most folks enough vitamin D for most of a week. As a rule of thumb, if you aren’t worried about getting a sunburn, then you aren’t getting vitamin D.

Vitamin D deficiency is surprising common around the world, with about a billion people affected. People who tend to stay out of the sun, people with darker skin, people north of Atlanta, and older people are all affected. There is a threshold for sun exposure. A sunbather on a sunny day in January in Boston could stay out all day and apart of the frost bite, would gain no vitamin D benefit. [1] But, a White person exposing only arms and legs, thinks short and a tee, need only stand in the Texas sun for 15 minutes for all the vitamin D for a couple weeks. A Black person would take about three times as long.

Now my dermatologist will counter that it would be so much easier and safer if we all just took a vitamin D supplement, and this is true. So, the full recommendation is to slather every citizen every day all day with sunscreen and also take a vitamin pill every day. How about this as an alternative? Don’t worry about the sun for 3 seasons of the year if you live north of Atlanta. In the summer, wear comfortable clothes and wait 15 minutes (if you are White and longer if you are Black) before putting on sunscreen in exposed areas. Easy to remember and will save you gallons of sunscreen.

The real issue here is the balance between the risks of melanoma, a very lethal skin cancer that is greatly enhanced by excess UV exposure, and the risks associated with vitamin D deficiency. Yes, the risks of melanoma are real. Recent data show that in the US there are about 106,000 cases annually with about 8,000 deaths. This makes it the 12^th most lethal cancer in the country. Compare this to lung cancer with 235,760 cases and 131,880 deaths. In contrast to the effect of UV rays on melanoma, research has shown a strong possible role for vitamin D deficiency in breast cancer risk. A recent meta-analysis combining 22 studies showed that women with vitamin D deficiency had 91% increased odds of having breast cancer. Those that said they took supplements had a 3% decreased risk. So much for supplements. [2] In fairness, another similar study of supplements and breast cancer mortality showed a 14% reduction with vitamin D supplements. [3] The same study showed no effect on overall mortality. Others have found roles for vitamin D in possibly preventing colon cancer[4], prostate cancer[5], and lung cancer.[6] If vitamin D can reduce the risk of these four big killers by only a small fraction, this might easily balance the effect of UV on melanoma. A recent meta-analysis of vitamin D clinical trials suggests that supplements may cause about a 20% reduction in overall cancer mortality. [7]

Now this may sound like I am an apostle of vitamin D. Not so. I have been around the field of Nutrition long enough to see things come in and out of vogue. Vitamin D was hot when we nutritionists and many in the general public thought it would prevent or cure everything from lupus to hangnails. That day has passed and a more sober view is setting in. Notice that I did not make any claims for vitamin D and COVID or for immune function. These are rather dubious claims. Even the 20% cancer reduction that I quoted above has been challenged. [8]

So, should we slather and supplement or just delay slathering and only in the summer? From the public health perspective, I think delaying in the summer is the better message because it has the added advantage of getting people outdoors where they can play, exercise, breath fresh air and lower risk of COVID. Some have suggested that insufficient sunlight is responsible for about 400,000 deaths per year in the United States. [9] While I personally think this may be an overestimate, it is interesting to compare this to the 8000 known melanoma deaths per year and the slather and supplement regimen my dermatologist recommends to prevent them.

Looks like I may need to have a talk with my dermatologist.

References

1. Hollis, B.W., Circulating 25-Hydroxyvitamin D Levels Indicative of Vitamin D Sufficiency: Implications for Establishing a New Effective Dietary Intake Recommendation for Vitamin D. The Journal of Nutrition, 2005. 135(2): p. 317-322.

2. Hossain, S., et al., Vitamin D and breast cancer: A systematic review and meta-analysis of observational studies. Clin Nutr ESPEN, 2019. 30: p. 170-184.

3. Zhang, Y., et al., Association between vitamin D supplementation and mortality: systematic review and meta-analysis. Bmj, 2019. 366: p. l4673.

4. Mahendra, A., et al., Vitamin D and gastrointestinal cancer. J Lab Physicians, 2018. 10(1): p. 1-5.

5. Trump, D.L. and J.B. Aragon-Ching, Vitamin D in prostate cancer. Asian J Androl, 2018. 20(3): p. 244-252.

6. Wei, H., et al., Associations of the risk of lung cancer with serum 25-hydroxyvitamin D level and dietary vitamin D intake: A dose-response PRISMA meta-analysis. Medicine (Baltimore), 2018. 97(37): p. e12282.

7. Manson, J.E., S.S. Bassuk, and J.E. Buring, Principal results of the VITamin D and OmegA-3 TriaL (VITAL) and updated meta-analyses of relevant vitamin D trials. J Steroid Biochem Mol Biol, 2020. 198: p. 105522.

8. Manson, J.E., et al., Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease. N Engl J Med, 2019. 380(1): p. 33-44.

9. Alfredsson, L., et al., Insufficient Sun Exposure Has Become a Real Public Health Problem. Int J Environ Res Public Health, 2020. 17(14).

Is America a Democratic Country?

I am asking my readers to consider what may seem like a rather obvious question. We Americans are quite proud of our democratic foundations as an example to the world. But, compared to other nations and other systems, we may find some deficiencies in our system of government. Herein, I will give you five examples to consider that show some weaknesses in our current system.

In light of much of the news lately, I want to make clear that I am going to discuss institutions and systems. There is a lot of divisiveness and certainly a great weakening of public discourse that has weakened our democracy, but that is a subject for another time. If you are interested, a fine editorial in the NY times addresses this issue nicely and dispassionately with solutions that we can all embrace.

Before we start, let’s see if we can define what we mean by a democracy. To me, democracy is a system of government that allows a majority to be fairly chosen to rule, while still allowing substantial rights to the minority. It is important to remember that our founding fathers, when writing our Constitution, had no concept of political parties or the immense loyalty they would derive and wield.

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Here then are institutional factors that have for years deeply flawed our democracy.

The Electoral College

Yes, that system by which we elect our president and vice president is quite undemocratic. We have this mantra from voting rights that we occasionally pull out, “One person, one vote.” But consider the reality of the process of the electoral college. The state of Wyoming has a population of 581,075 and 3 electoral votes. The state of California has a population of 39,613,493 with 54 electoral votes in the 2024 election. That means that the voters in Wyoming have 3.8 times the voting power for the president than voters in California. Some democracy! Of course, this could be fixed with a constitutional amendment, but do you think that Wyoming will approve that? States could partially solve the problem themselves by apportioning electoral votes in proportion to the popular vote. But would California approve that if Wyoming doesn’t. We are in a stalemate. Others have reviewed the situation with similar conclusions.

The Filibuster Rule

This is the complex rule by which every act that does not involve money must pass the Senate by a 60-vote majority. This is very unlikely in that evenly divided chamber. And so, apart from budgets (and Supreme Court appointments), nothing substantial gets passed in Congress. The filibuster is also widely misunderstood, even by senators. While I favor protecting the minority party, I would also like a government that solves problems and advances the welfare of the country. With our deeply divided political parties who consistently chose party over country, we all are the losers. Compromise is no longer possible. This rule has to go. There are also various ways that it could be reformed.

Voting Rights

In some of the most shameful legislation of the past two years, many states have passed laws limiting the ability to vote. They use conspiracy theories and fake news to create barriers to the very people who might vote them out of office. This transparent raw use of political power is an embarrassment to our founding fathers and the many who have sacrificed for our freedoms. The only direction in which voting legislation should go is to create more access, more freedoms, less barriers, and more openness and transparency in the process. The John Lewis Voting Rights Act is before Congress at this point and would correct many of these problems but has little chance of passing.

Gerrymandering

The apportionment of voting districts has become a blood sport for state legislatures. The sole purpose is to stay in power by any means possible. My own state of North Carolina is an example. Our state is fairly evenly split with 36% registered Democrats and 30% registered Republicans, but you wouldn’t know it with our congressional representatives being 9 Republicans and 5 Democrats. How was this done? Our state house is 69-51 Republican, and our state Senate is 28-22 Republican. Gerrymandered districts have been in court almost continuously for the last couple of decades. The Republicans will do whatever it takes to stay in power, even as they lose the edge in the popular vote. If you think is just a Republican phenomenon then check out Maryland where the opposite is happening.

Lobbyists

This is the quietly undemocratic arm of government. If you don’t have a lobbyist working for you then you aren’t getting the benefits you deserve from your government. What? You say that you have a congressional representative? Sorry, that doesn’t count in the halls of power. You may think your vote brought your representative to Washington, but it was actually lobbying money. Technically, any citizen can walk the halls of Washington and plead their case. But there are several factors that tips the scale in undemocratic ways. Most obviously is the complexity of the governmental apparatus. Who do you go see and specifically what do you ask for? So, who benefits most from our current lobbying process? The most likely to be engaged are those with the most to gain and with the concentrated wealth and focused need to make the investment. That would include specific industries with specific policy and legislative needs. Who loses? That would be large unorganized groups with vague needs that have no organization or time to organize. That would include poor people and consumers of the products from said industries. These also tend to come from certain localities, think rural, and certain minorities, think Hispanics. So, lobbying tilts our democracy in favor of those with money and a knowledge of the apparatus of government, not those who often need the protection of their government.

A Democratic Solution?

Is there a possible fix to these issues that might improve the democratic nature of our “democracy”? It is not an easy fix. We would need lobbyists to fix lobbying and new legislatures to undo legislative gerrymanders that set legislatures in stone. We would need representatives who would be willing to give voting rights to their possible opponents and undo the legislative barricade known as the filibuster. And can anyone see Wyoming and California agreeing on anything? This is how empires slowly rot from the inside and collapse. I am of the baby boomer generation. We grew up singing, “If I had a hammer”, thinking that we would change the world before we were 30. Sorry gang. It looks like even in retirement we still need to be swinging that hammer if we want to see our grandchildren in a more democratic country. GenX and Millennials, you’re up next. It will be a long fight.

Book Review of Theistic Evolution

Theistic Evolution, A Scientific, Philosophical, and Theological Critique. Edited by J.P. Moreland, S. C. Meyer, C. Shaw, A.K. Gauger, W. Grudem. Crossway, Wheaton, Il. 2017

A pastor friend of mine gave me this tome of 1007 page and 31 chapters because he knew my interest in the topic. It was very generous and thoughtful of him. I will admit that I did not read the whole thing but read substantial portions that fit my interest and expertise and gave me enough to form a clear opinion of the work.

First of all, this is an awesome work by an astounding number of accomplished authors and editors. They are to be commended for the consistency of the work. It is an intellectual tour de force. It took me several months to get through what I did read, which was most of eight chapters. It was engaging, mostly well-written, though occasional rather thick and incomprehensible. I focused most on the two Introductions, some of the Science chapters, and some of the Philosophy chapters. I avoided the Theology section. As I was reading it, I reasoned that someone somewhere must have a written a scholarly review. This might have come from the society of which I was a member, the American Scientific Affiliation, a group a Christians in the sciences. With only a little searching in their journal Perspective on Science and Christian Faith, I found a 20-page article written by Denis Lamoureux, an ardent defender of theistic evolution, or as he prefers to call it, “evolutionary creation.” As a scholar in this area who I greatly admire, he has done a far better job that I could of understanding and countering the arguments of the text, particularly on philosophical and theological grounds. Herein, I can only add my modest insights as a working scientist and believing Christian.

What became very clear from the first few pages of the book was that this book was not really about theistic evolution. It was about an alternative theory called Intelligent Design (ID). ID posits that God specifically intervened in the creation or evolution process to direct or accelerate the development of life and species. Theistic evolution (TE) by contrast says that God was sovereign over the whole process of creation and evolution but that it happened by entirely understandable means, i.e scientifically understandable means. So, the overall purpose of the book was to criticize TE and thereby to validate ID. From the outset, of course, this is a false premise and to say the least a false title to the book. A better title might have been Countering Theistic Evolution in Support of Intelligent Design. Putting down one theory does not prove another.

One of the greatest faults of the book was its failure to defend ID. At no point in the eight chapters that I read, especially the philosophical chapters, was ID ever really clearly defended. Much ink was spilt in trying to tear down TE arguments but not one shred of positive evidence was given to support the ID view. In the scientific chapters, much time was spent on why current evolutionary theory was wrong. But not a single positive verifiable testable case was given for ID. I ended up taking a bookmark and writing this on it, “Where is any verifiable evidence for intelligent design? An absence of support for other theories doesn’t count.”

The book spends 17 chapters tearing down the current scientific understanding of evolution as false, erroneous and inadequate. I skimmed most of these chapters. They entirely miss the point. Scientists follow science. If it is all completely wrong, then the scientists studying evolution will just keep looking for scientific and natural answers. Scientist love gaps in their science. This is what motivates us to write grants and return to the lab every day. In my own field of Nutrition, I could easily point out a number of things we don’t know. Does this mean that I now need to call in a God Hypothesis to explain these? No, it just means I need to return to the lab and write more grants. Or let’s take the field of astronomy and the current puzzle about what dark matter is. Astronomers are puzzled and intrigued. Do any of them say, “Well, I can’t explain it so it must be God?” No, they don’t. They just keep working on it. At one point there were gaps in the fossil record that some folks loved to point to as places where God obviously must have been at work. But in the last couple of decades there has been an explosion in new-found fossils that has closed many of these gaps. Where did God go? He was always there to be marveled at and worshiped for his creatively and manifold mercies.

The biggest criticism of ID is that it is a God-of-the-gaps theory. This was addressed directly and woefully inadequately in the philosophy chapters. The authors said that what scientists view as gaps, ID folks view as an opportunity. This is wordplay that has and will come back to haunt them many times over, especially in this genomics age.

The most interesting arguments in the book were why God is excluded from modern science. If we want to search for all Truth, shouldn’t we be willing to open any door and willing to hear any theory. I can admit to the attraction of this simple argument. The actual fact is that for the past 700-800 years of modern science, we haven’t needed the God hypothesis. In fact, the folks who gave us modern science in Europe, mostly monks from the Middle Ages, were the ones who stood firmly on the foundation that all natural observable event should be explained by observable repeatable science without recourse to divine explanations. While they understood that a creative and active God was the first and primary cause of all natural phenomenon, the duty of us humans was to search out natural explanations. Until the advent of ID, we have been actively and aggressively shedding the God hypothesis with good effect. If the ID folks could show even one conclusive verifiable example of the God hypothesis closing a gap of science somewhere, then maybe they would have an audience. But they have not.

Quite to the contrary, in the philosophy chapters they made some astonishing claims. At one point, in an attempt to show that ID or any creationism was indeed a scientifically sound perspective, the authors argued that since Darwin himself argued against creationism in his scientific text, Origins, then creationism itself and ID derivatives must be considered science. The argument is that you cannot argue against the science of ID without first validating it as a true science. I laughed out loud. Later it is argued that TE folks are not allowed to use theology since their science allow no God. Therefore, ID is unassailable from either the science or the theology. I was rolling in the aisles.

Finally, I turned to the Lamoureux review, which I do recommend. He reaffirmed several things that I saw. He especially drilled down on the God-of-the-gaps problem. He showed how unscientific and how unbiblical it was. He reaffirms the strength of the fossil record and the shrinking nature of scientific gaps. He showed how genomic data confirms common descent in evolution. But his biggest criticism was the surprising and newly revealed biblical nature of ID. Previously, especially in the courts, ID folks have tried to wave their hands and declare that they have no theological interest in what or who the Intelligent Designer might me. Now in Theistic Evolution they are explicitly Evangelical Christians with 4 theological chapters and hundreds of biblical references. He calls out their concordism. This is the belief that there is modern scientific information in the Bible. A more flexible understanding is that the authors of the Bible understood the world around them using the science of the times. The Bible reflects this with no special revelation of modern science. Lamoureux has some great and rather shocking quotes that the authors have made elsewhere supporting unscientific views from scripture such as a seven-day creation and that the curse of sin, including thorns and diseases and earthquakes came only after Adam. Lamoureux’s point is that if these authors accept concordism, then they have bought the whole field including the entire cosmology of 1000 BC. They cannot believe in a seven-day creation and yet think that the earth revolves around the sun. One is from the science of biblical times, and one is from the science of our times that is contradicted by the biblical text.

In conclusion, I found the book in part misleading, in part thought disappointing, and in part comical. I came away with a stronger faith in science and in a mighty God and a savior Jesus who meets us where we are and takes us where we need to be. Rightly understood, a biblical faith and a scientific understanding of the world do not need to conflict.

COVID from the virus’s point of view

There are a lot of headlines and news and predictions about where COVID has come from and where it is going. While lots of good studies have been done and lots has been learned, I want to suggest that a lot can be learned by just looking at this pandemic from the virus’s point of view. While I am not a virologist myself, it is fairly easy to image how this can happen and what is to the virus’s advantage and disadvantage in surviving and thriving.

Let’s start with a pre-COVID virus in a bat. From the virus’s perspective it is all about the success of propagating its RNA, its reproductive molecule. A virus is barely more than an RNA molecule packed with a minimum of reproductive machinery and a protective coating that doubles as a docking molecule looking for a cell type in a host to attach to. Success for a virus is spreading itself far and wide. The more hosts the better, the more copies the better. Its method of reproduction is fairly simple and fairly prone to error, which is actually to its advantage since this allows it to mutate to overcome various barriers to its spread.

So, a COVID-like virus in a bat is happily reproducing and mutating and spreading around among bats. A number of these viruses end up in humans and chickens and pigs by the natural processes of moving through the air. But this does the virus no good since those protective coats cannot bind or attach to any cell types in humans, chickens, or pigs. But then, by random chance, its RNA gets mutated in just one or two places and the shape of the protective coat, we now know to call them the spike proteins, changes just enough to stick to a cell type in the lungs of pigs. (Of course, I am fabricating some of this because we do not know the exact path of the evolution of COVID, but this is a common pathway for a number of these flu-like viruses.) Now here is where it gets complex. The $10 question is whether the pigs get sick? Does it really matter to the propagation and success of the virus whether its host gets sick and maybe dies? Only partially. Think like a virus. If the pig gets sick enough to cough and sneeze and spew clouds of viruses into its environment, then yes, it is an advantage. It the pig rolls over and dies within two days of catching the bug without barely a cough, then it is probably no advantage to the evolving virus. Hence, we see a lot of successful viral diseases that involve clear modes of dispersal such as the common colds with lots of sneezing or certain stomach bugs that cause copious diarrhea or vomiting.

In another interesting and devious twist, consider when most of our viral diseases are most contagious. Is it when we have been diagnosed and are sick in our beds and masked up and isolated? No. Most often, we are unknowingly spreading the disease in the earliest days when we don’t even know we have it, in the pre-symptomatic period. If you are thinking like a virus, this is genius.

So, back to our pigs who are in close contact with their human owners and are being taken to markets with even more humans and pigs and are being sold and transported around the country. You already know the next step. Another mutation happens and those viruses that the pigs were transmitting to their owner without much problem suddenly become a problem because the mutated spike protein can now attach to the cells of the human lung. It is amazing to think that this disease, now officially called COVID-19, probably came about by a change of one or two molecules with one or two viruses within one pig in China in the summer of 2019, or some other equally improbable event.

This first variant of COVID-19 that attacked humans may not have been very effective. It might not have bound very well and might not have used the human reproductive machinery very well. But slowly with additional mutations it probably got more effective until it reached the point of being recognized and being named the alpha variant.

Now we can see that in the lifecycle of the virus there are several problems to be overcome and optimized. Hosts must be infected; viruses need to be reproduced efficiently, and they have to be spread widely. To be infected, a host must take in the virus to the cell to which the virus attaches, and it has to attach firmly. The fewer inhaled viruses that can kick off an infection the better. The omicron variant seems to be particularly good at infection. Next the host cells need to be co-opted to make more viruses. The more the better. Again, it appears that delta and now omicron have become increasingly productive of new viruses. As for the spread, we are now learning that the R0 of omicron is probably higher than delta. The R0, or R-naught, is the average number of people that one infected person infects. Both delta and omicron seem to be running about 3-7. These are wide ranges, but it means that if a person is infected with omicron, they will infect about 3-7 more before becoming non-infective. This explains why COVID is traveling so fast right now.

But what about severe illnesses and deaths? Doesn’t this matter to the virus? It certainly matters to us. As I explained above, it is all about propagation, and sickness only helps the virus if it helps propagation. And dead people don’t propagate viruses. So, this gives us some hint on how this virus might evolve. If you were the virus, would choose to infect people and give them no symptoms while you went through your lifecycle and spread, or would you choose to kill off a large fraction of your hosts after they have been quarantined in a hospital for two weeks? I vote for fewer symptoms and fewer deaths. I suspect that the pre-symptomatic but infectious phase is going to get longer and longer while the sick but not spreading phase is going to get shorter and shorter. Deaths that don’t help spread viruses will also probably go down. This a conjecture, but I have read that most virologists agree with this probable scenario. Omicron seems to be headed in this direction with more infections and less lethality.

But this should not make us complacent. This is a very smart virus with a long-term plan to take over the world. It will patiently lay in wait until we are not watching and then a mutant might spring up that is much more infectious and also, for a short time, much more lethal. And we can also expect variants to emerge that resist or avoid the vaccines but are still very infectious. Omicron also seems to be taking us down that road.

So, in thinking like a virus we have learned a couple things. Viruses are wicked smart but not necessarily committed serial murderers. They just want to take over the world. Please keep up those vaccinations and boosters. Please encourage worldwide vaccinations. Please keep those masks up.

This link can help find a vaccine near you in the US.

Paleo, Keto, and Gluten-free Diets

A Nutritionist’s Perspective

First, a quick preamble. This is the first in what I hope will be a series of posts on food and nutrition. This essay was adopted and updated from a talk I gave three years ago on my campus at Appalachian State University in Boone, NC. I had great help from my graduate student at the time, Drew Hilton, in preparing this material.

I want to talk about diets and some of the problems with undertaking one to lose weight. To make this more interesting and applicable I have decided to discuss three popular diets and to draw lessons from them that can be applied to all diets. The diets I have chosen are generally considered fad diets and are not generally recommended by dietitians. That will heighten the lessons we can draw. I will try to be objective about the pros and cons of these diets.

A word of caution here. I am not a Registered Dietitian, nor do I pretend to be able to prescribe specific foods and diets to specific people. I am an expert in the biochemistry of nutrition and metabolism, and I tend to see diets from that perspective. So, let’s get started.

I have chosen three diets to draw lessons from, the paleo diet, the keto diet, and the gluten-free diet. Many people would call these “fad diets” because they tend to be out of favor with nutritional experts and their popularity waxes and wanes, but they still remain popular with many people today. We will address them one at a time. My goals here are not to discredit every diet out there or completely discourage you from undertaking a diet if you need. I hope to give some sensible advice riffing off these diets that many of my readers have already tried.First though, why are so many people dieting? America has been in an obesity epidemic for about the last 70 years. And we have seen the consequences in rising cases of diabetes and hypertension and many other chronic diseases. People are constantly worried about their weight. About 43% of teenage girls admit to being recently on a diet. Dieting is a $43 billion industry with videos, supplements, books, mail order foods, and medications for dieters. A search for “diet books” on Amazon brings up 60,000 hits. Recent research showed that half of all diet advertisements had at least one false claim. Here is one of my favorites. And for all of that, only about 5% of dieters are successful in keeping the weight off.

Photo by uff2cuff41uff52uff41 on Pexels.com

The Paleo Diet

The paleo diet is a diet loosely based on what our paleolithic ancestors may have eaten. It eliminates dairy, grains, sugar, legumes, processed oils, salt, alcohol, coffee, and most processed foods. There was growing interest in the 80s and 90s, but Loren Cordain’s book The Paleo Diet in 2002 established the diet as a national phenomenon. The rationale is that we are evolutionarily adapted best to a diet prior to the development of agriculture in the Neolithic age. Hence, agriculturally developed foods such as grains, dairy and sugar are discouraged on this diet. If we return to this diet we will avoid the modern degenerative diseases- heart disease, diabetes, and cancers. Characteristics of an ideal paleo diet include higher protein, lower carbs, higher fiber, higher unsaturated fats, higher potassium, alkaline load, and higher vitamins, minerals, antioxidants, and phytochemicals. Prohibited foods include cereal grains, legumes, dairy, refined sugar, potatoes, processed foods, refined vegetable oils, and salt. Promoted foods include grass-fed /free-range meats, fruits and vegetables, fish/seafood, eggs, nuts/seeds, and healthful oils (olive, walnut, avocado, coconut, etc.). Obviously, the paleo diet tends to cost more than the usual western diet.

Here are some of the errors that I see in the philosophy underpinning the paleo diet. We have a rather rudimentary understanding of what paleolithic people ate, but what we know for sure is that by that time humans were all over the world and eating all kinds of foods. There is no single paleolithic diet. Another wrong assumption is that the human genome has not changed or evolved since then and since the advent of agriculture. One simple counterexample is the advent of lactose tolerance in some folks, allowing for the common practice of drinking milk. This probably came about in more than one place by a genetic mutation about 10,000 years ago. Also erroneous is the simple assumption that the foods our ancestors ate are the same ones available in the supermarket. What our ancestors might have called “corn” or “carrots” bear almost no resemblance to those products today. A true paleo diet would be almost inedible to the modern consumer. Finally, the paleo adherent gives no credit to the marvelously flexible human digestive physiology. Consider all the diets that currently exist around the world that humans thrive on. We are truly a wonderfully omnivorous and adaptive species that seems to be able to do rather well on almost any diet. My apologies here to my dietitian friends who are cringing at the thought of all their well-crafted dietary recommendations being subverted.

All that said, I’m not suggesting that you will die a short terrible death on the paleo diet. Let’s take a quick look at some scientific studies. There aren’t many of these, but we can draw some conclusions. In a study titled, “Long-term effects of a Palaeolithic-type diet in obese postmenopausal women: a 2-year randomized trial”, the researchers ran a trial in which they trained half of the subjects to prepare a paleo diet and half a healthy control diet. They concluded that, “A Palaeolithic-type diet has greater beneficial effects vs a [control diet] regarding fat mass, abdominal obesity and triglyceride levels in obese postmenopausal women.” In another more comprehensive study titled “Paleolithic nutrition for metabolic syndrome: systematic review and meta-analysis” the authors summarized the results from four studies, “The Paleolithic diet resulted in greater short-term improvements in metabolic syndrome components than did guideline-based control diets.”

So, these studies support the benefits of the paleo diet as a weight loss diet that improves our lab numbers. While this is encouraging for paleo enthusiasts, it is not surprising. Restrictive diets tend to result in weight loss. Also, diets that can decrease hunger pains are also helpful. We know that foods higher in protein and fats tend to be satiating, meaning the eater feels full longer. This diet and the keto diet both are higher in protein and fat than the normal western diet. If I suggested a diet to you that removed all grains that began with the letters W and S and all vegetables and fruits and began with C and G, you would lose weight, if only because you would spend half your day in the grocery store, trying to figure out what not to eat. The question I would pose to purveyors of these diets is whether the success is in the story they tell or the restrictions they impose.

Secondly, almost any diet that results in weight loss almost invariably results in improved metabolic scores. This often puzzles the critics. How can a high fat diet result in lower blood cholesterol levels or lower blood pressure? It happens because the high fat diet is more satiating and results in weight loss that results in healthier cholesterol and blood pressure.

So, is the paleo diet safe? Three thoughts. Safe compared to what diet? First of all, we know that the standard American diet, shared by many around the world, is not exactly the epitome of perfect nutrition. For starters, it has too much sugar, not enough fiber, is low in some key minerals and has way too much salt. So, compared to that diet, many diets are better. But compared to a healthy vegetarian diet, I would vote for the veggies. Two, at what weight? One topic I am not addressing here is who should be on a diet and why. It would be (and might be someday) a topic for a series of blogs. Let me say simply that the risks associated with obesity go up with weight and the benefits of weight loss and being on any diet that works go up with weight. For normal weight folks, I would take you back to the faulty assumptions and the numerous restrictions and ask you to consider a more enjoyable and healthier alternative. Finally, consider the cost. For the extra cost you are giving up beans, beer, and bread.

The Keto Diet

Having covered some of the common issues, these next two diets will go more quickly. First is an issue with names. The original ketogenic diet was a true medical diet that was quite extreme, with up to 90% of energy coming from fat and protein compared to the usual 50%. It was used successfully to treat children with refractory epilepsy. The so-called “Keto Diet” in modern use is nowhere near that in proportions. Most keto diets are low-carbohydrate diets with about 20-30% compared to the usual 50-60% carbs. The most famous of these diets is the Atkin’s Diet, named after the famous doctor who invented it.

These diets are very popular and much scientific research has been published on them. One major study titled “Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomized controlled trials” summarized 13 clinical trials of 12 months or longer. They found, “Overall, 37% dropout rate. Average 37% carbs, Keto diet had 0.91 kg greater weight loss, lower triglycerides, diastolic BP, and LDL and higher HDL.” Several points to make here. There is always a high dropout rate from weight loss studies. Weight loss is hard and keeping people in the studies is hard. Note the high carbs at 37%. This is not all that restrictive. Note the marginal benefit of 0.91 kg, about 2 lbs for the keto groups. The benefits to triglycerides, blood pressure, LDL, and HDL, were equally small.

The physiology of the keto diet is intriguing and deserves some attention. The basic idea is that if we can lower the incoming carbohydrates, then we can lower the blood glucose levels. This will have specific benefits for people tending towards or in diabetes. If the body gets low in blood glucose, which it absolutely needs to fuel the brain, then it has a backup system called ketogenesis. In ketogenesis a group of metabolites call ketone-bodies can be produced from fats when sugars, like glucose, are in low supply. Keto enthusiasts will emphasize at this point that burning up fat is what dieting is all about, so this state called ketosis and being fueled by ketone bodies is a good state to be in. But the body still sees it as an emergency state, not the preferred state. As an analogy, imagine working in a building where the fire alarm was sounding about half the time.

Is the keto diet safe? Three concerns. Based on the physiology I just described, certain folks should be concerned. Folks who can run into super low blood glucose levels should beware of this diet. That would include folks with diabetes who are on glucose controlling drugs such as insulin. These ketone bodies, in high enough concentration can be acidic. There is a small risk of ketoacidosis. This takes us back to the original definition of the keto diet and the question of just how restrictive of carbs the diet is. With moderate carbs at 30-40%, there is going to be little ketosis. At low carbs of 10-20%, ketosis will be frequent. When ketones are high and glucose is low, the brain says, “Hungry.” This doesn’t sound all that pleasant. So, what is the quality of life here, especially given the increased cost again, and the restrictive diet. Remember, no doughnuts, drinks, or Doritos. As stated before, any benefits we see from this diet are more than likely due to the restrictions that lead to modest weight loss that lead to healthier lab numbers.

Gluten-free diet

Gluten is a protein in 3 grains: wheat, barley, and rye. It is also found in processed foods such as soy sauce, salad dressing, food starch, beer, etc.. The diet was first developed for people with celiac disease, an autoimmune disease that affects the intestine and slowly blocks absorption of nutrients. Untreated leads to death from malnutrition. Here is an interesting full disclosure for my readers. I have celiac disease. I have been diagnosed for about 12 years. While there are inconveniences to be sure, it is one of the least troublesome autoimmune diseases to have.

The fad diet we know today largely developed in the early 21st century with books Grain Brain and Wheat Belly, condemning wheat and other grains as bad for health. People started diagnosing themselves with “non-celiac gluten sensitivity” and popularizing gluten-free diets for many health benefits. The medical profession has been puzzled by this new condition and has slowly recognized it. Gluten-free products are now a $15 billion food industry.

There is now a cross-over between gluten-sensitivity and the FODMAP diet and Crohn’s disease and irritable bowel syndrome. Common symptoms include abdominal pain, bloating, and gas. This is a very complex topic. Suffice it to say that Crohn’s and irritable bowel are both mystifying intestinal conditions that are difficult to treat and may be diet related and may be related to the carbohydrates in the diet. Gluten may be mixed up in there somewhere. Others have suggested gluten-free diets as possible cures for schizophrenia, fibromyalgia, and endometriosis. These have been largely disproven.

Gluten-free diets have not been taken up as often as the other diets for weight-loss. To the extent that they have and to the extent that studies have followed up, it appears that the results follow our previously established wisdom that restricting a diet for any reason often means less calories, which generally means weight loss and improved number. But if you are restricting wheat, you must imagine a diet that restricts donuts, cakes, and most office treats. Imagining losing weight on that diet is not too hard.

Please allow me just a minute to elaborate on the common errors found in the popular book Wheat Belly. Many of the benefits of eliminating wheat are due to weight loss, not to some toxic properties of wheat. The book has many testimonials, but few clinical trial results. While the author will point to the dangers of various constituents of foods, none of the dangerous properties were unique to wheat starches or proteins. The author claims that dramatic changes to the gluten content of wheat varieties has happened over time, especially since the Green Revolution of the 50s and 60s. However, recent research has clearly shown that no changes in wheat composition has occurred. The connections between a large number of diseases and wheat are completely unproven.

Here are some concerns that nutritionists have about gluten-free products currently on the market. They tend to be lower in fiber than their glutenous alternatives. They are not necessarily fortified with B vitamins and iron. They often contain more salt, fat, and sugar. They tend to be more than two times as expensive.

Overall Conclusions

We have seen some common threads through these three diets. Let me summarize those for you here:

Most fad diets won’t hurt in the short-term.
Most diet benefits come from restrictions that lead to weight loss.
Long-term adherence is hard and may not be as helpful as one would like.
They are almost always more expensive.

If these three diets are not recommended in the long-term, what makes a good diet? Here are some common-sense suggestions:

One you can stay on for a lifetime
That is balanced and minimally restrictive
That lowers metabolic syndrome and other disease risk factors
That moderates weight slowly

Best Diets Overall

Best Diet Advice from author Michael Pollan

My favorite food and nutrition author is actually not a nutritionist. He is a journalist who has written several thoughtful books on the subject. At the end of one of his books he give this advise for a good diet.

Eat (whole) foods
Not too much
Mostly from plants