I don’t know about you guys, but I like these link-o-rama posts because they let me get rid of a bunch of tabs on Firefox and disseminate info that probably isn’t worth an entire post.

First, let me start out by linking to one of my wife’s recent posts.  We’ve had a spate of people writing us through the website asking about cookbooks, of all things.  She did a post a couple of months ago about her favorite cookbooks.  In case you missed it, here it is.

Second, I’m going to start using these link-o-ramas to link to some of my older posts that I think would be of interest to a lot of people now.  One that I thought was pretty good on how to dissect a scientific article didn’t get many readers since I wrote it back when maybe three people read this blog.  The notion that it didn’t get many readers is evidenced by the fact that there are zero comments on it.  So, without further ado, here is Baboon Business.

After all the recent posts about the savagery of the nature, I thought I would throw this item into the mix just to show that nature can be tamed, at least in the short run.  There is a guy who is a fixture in downtown Santa Barbara who has a dog, a cat and a rat as pets.  He is always down on State Street, the main street running through town, with the cat riding on the back of the dog, and the rat riding on the back of the cat.  Here is the YouTube, so you can see for yourselves.

Click here to view the embedded video.

I came across an interesting article titled Is Food the New Sex? in a little journal I get called Policy Review.   The writer of the article posits that our appetites for food and sex have more or less switched positions in our hierarchies of taboos since the 1950s.  She uses a woman who was a housewife in her 30s in the 1950s and her hypothetical granddaughter who is in her 30s today.  The housewife of the 1950s had no taboos on food and all kinds of taboos about sex whereas her granddaughter reads every label and is scared to death of her food, yet expects to live together for a trial run before marriage to her boyfriend and has friends with all sorts of alternative lifestyles.  A fun, but long, article to read.

What follows are a couple of quotes separated by years, but nevertheless related.  So I figured I would post them juxtaposed so that the connection would be obvious.  The first is from Ludwig von Mises (1881-1973), an economist of the Austrian school.

The luxury of today is the necessity of tomorrow. Every advance first comes into being as the luxury of a few rich people, only to become, after a time, an indispensable necessity taken for granted by everyone. Luxury consumption provides industry with the stimulus to discover and introduce new, things. It is one of the dynamic factors in our economy. To it we owe the progressive innovations by which the standard of living of all strata of the population has been gradually raised.

The next quote is from the transcript of a CNBC interview with Warren Buffett last year.  I don’t agree with Mr. Buffett on everything, but I do on this.

…we’ve had a number of recessions in this country; in fact, we had a Great Depression, we had–we’ve got world wars. And throughout, the genius of the American economy, our emphasis on a meritocracy and a market system and a rule of law has enabled generation after generation to live better than their parents did. And, I mean, most of the people in this room, practically all of them last night, lived better than John D. Rockefeller lived. I mean, all kinds of things have happened. And in the 20th century alone, the standard of living of the average American went up seven for one. There’s never been a period like it in history. And that’s not an accident. It’s because we unleash human potential and will continue to do that in the future.

Here is a link to a site containing a video of Gary Taubes, Dr. Jay Wortman, Dr. Alan Einstein and me taken last year at a conference in Phoenix.  We’re all expounding on the problems of the low-fat diet.  It’s the first video in the link.  I haven’t watched the other two, so I can’t tell you what’s in those.

For those of you interested in intermittent fasting, here is an article on the subject from the Los Angeles Times.  I’m working on another post on IF that I hope to have up within the next couple of weeks.

Researchers aren’t sure why the body apparently benefits from a state of mini-starvation. One theory is that the process produces just enough stress in cells to be good. “What our evidence suggests is that nerve cells in animals that are on dietary energy restriction are under mild stress,” Mattson says. “It’s a mild stress that stimulates the production of proteins that protect the neurons against more severe stress.”

What they do know is that occasionally going without food or reducing calories daily makes the body more sensitive to insulin, which helps maintain normal blood sugar levels. And animal studies suggest calorie restriction may reduce the risk of cancer by slowing the growth of abnormal cells.

I’ve got about a hundred (93 to be exact) tabs up on my Firefox browser, many of which are filled with articles about which I would like to post.  But these articles either keep getting displaced by something more timely or more blogworthy or even more substantive.  Many are interesting, but not worth an entire long post.  So, I decided to do one of those sort of potpourri linkfest things like so many bloggers do and be able to close a bunch of these tabs.  Plus it gives me a chance to indulge in my interest in the political situation without having to devote an entire post to it.

First and foremost, I want to link to the latest post in MD’s blog.  When I posted earlier about our meals in Mexico, I mentioned this great Andalusian gazpacho recipe she had.  A bunch of people asked for it, so she put it up.

Richard Feinman sent me a link to an annoying Mayo Clinic nutrition blog by a couple of ignorant dietitians.  Reading stuff like this that is written with such certainty always makes me think of a couple of lines from Shakespeare’s’ Measure for Measure:

Man, proud man!
Dress’d in a little brief authority:
Most ignorant of what he’s most assur’d.

These women are oblivious to the fact that the studies upon which they base their idiotic ramblings are worthless as proof of the nonsense they spout.  The first considers a diet with 45 percent of calories as a low-carb diet.  Oh, really?  The second is an observational study, and, as such, totally useless for proving causality.  Yet, in their words, these studies

caused a couple of “aha” moments

for them.  I suppose they could have meant, “aha, we’re really clueless.”

I read a nice little summary in the journal Hepatology of a study published in Nature Medicine.  The study looked at chaperone-mediated autophagy (CMA) and aging.  As we age, we tend to accumulate protein debris in our cells.  Over time this accumulation interfers with the proper functioning of the cell and is thought to be one of the components of aging and cellular sensescence.  Organelles within the cell called lysosomes are charged with the responsibility of basically chewing up (auto-phagy: self eating) these junk proteins to keep the cell free of garbage, allowing it to do its job.  Chaperones are proteins that bind to junk proteins and move them into the lysosomes for degradation.  Researchers developed transgenic mice that had the ability to make more of the chaperone proteins than normal mice, giving them the ability to increase the degradation of junk protein.  Their study showed that increasing the CMA in these mice resulted in lower accumulation of junk protein, better ability to deal with protein damage, and improved organ function.  The reason I like this paper so much is that it confirms what I wrote in one of my favorite posts from the past about ketosis doing the same thing.  Maybe you don’t have to be a transgenic mouse to get the benefits of cleaner cells; maybe just staying in ketosis more of the time will do the job, too.

Politics alert! POLITICS ALERT! POLITICS ALERT! For those of you who chastise me for daring to bring politics into what is at heart a nutritional blog, beware: politics to follow.  If you want to avoid reading about anything to do with politics and get back to the nutrition stuff, skip on down until the politics alert has been removed.

Here is one from the Karma-is-wonderful department.  By now everyone knows that Tom Daschle got the rug pulled out from beneath him in his attempt to become the secretary of Health and Human Services in the Obama administration because of his failure to pay over $100,000 in taxes.  And everyone knows that former Senator Daschle didn’t pay taxes on the car and driver he was provided as part of one of his lobbying efforts. (One wonders what kind of car would run up enough imputed income to result in over $100,000 in taxes.) But what many people might not know is that Mr. Daschle, in his days as a Senator from South Dakota, ran ads showing that he drove an old car while working in Washington for the folks back home.  The irony is so sweet.

Click here to view the embedded video.

While we’re at it, you might enjoy this cartoonist’s ideas on how we can afford the stimulus package being argued in Congress. Now we can add one more with Solis.  We really can begin to refill the coffers if this keeps up.

An insightful article in the Economist from a few weeks ago got me thinking.  This piece was talking about the government in the UK, but it could be applied to any government anywhere when faced with a crisis.  Governments all follow these two rules:

First, eschew all blame.
Second, do something.

I’ve never seen our own government here in the US not follow these rules.  For example, let’s look at the subprime mortgage situation that has gotten us into our current bad way.  When the house of cards began to fall, what did the government do?  Pointed fingers at everyone but itself.  It eschewed all blame.  It was the fault of all the independent mortgage lenders making shaky loans; it was greed on Wall Street; it was Bernard Madoff.  And on and on and on.

And what did our government then do, after all the finger pointing?  It did something.  It passed an emergency stimulus bill to the tune of $700 billion to keep all of these people from losing their homes and to keep the economy from cratering as a result.  As near as I can tell, I have about 5,000 people who read this blog every day.  And those 5,000 people know a lot of other people.  In fact, I would imagine that, on average, each of these 5,000 people probably knows or knows of at least 50 people, which means that all of us together know around 250,000 people.  Of all these people, some are bound to be in financial trouble and are behind on their mortgages.  So I ask you this, has anyone reading this blog learned of anyone he/she personally knows getting mortgage help from this $700 billion?  I didn’t think so.

So the government pointed fingers and did something.  We know that whatever it did, didn’t really help the individual people who were hurting during this mess.  It helped Wall Street guys get their bonuses, and it helped management of troubled banks get their health insurance premiums covered, and it redecorated a few offices, so maybe the do-something part of the equation actually helped some individuals (though not the ones it was sold to us to help).  But what about the blame?  Wasn’t it Wall Street greed and independent mortgage brokers?  As Will Rogers used to say, “All I know is what I read in the newspapers.”  I’m kind of the same way, but I like to think I’m a little bit of a critical reader.  The single best and most comprehensive piece I’ve read yet on the current financial debacle was written several months ago in The Spectator, published in London, and my favorite weekly magazine.  The author of this article musters the data to show that it is the government itself that is at fault.  And if you don’t believe the author, here is a piece written in the New York Times on September 30, 1999 when the seeds for this subprime meltdown were sown, discussing the potential problems that could come to pass.  Sadly, they did.

On the global warming front, here is part of an email I received today from an outraged friend of mine in the UK.  This friend is a famous author who hobnobs with everyone who is anyone in the UK.  Name withheld mainly because it’s too late at night there for me to be asking for permission.

Tonight I sat watching television which I don`t do a huge amount of. We have been snowed in for 4 days and tonight it is minus 8. I watched a hapless man from a council lamenting that they had run out of salt and grit so the county`s roads would be death traps. Asked why their stocks were so low, he said because they had all been led to believe we would never have winters like this again because of GW. so they spent the money on recycling and ‘Climate Change initiatives’ instead. ‘And I have to say,’ this brave man ended ‘I think we`ve all been badly conned.’   Ten minutes later the US Vice President Biden appeared on my screen – what a pleased-with-himself guy he is. In Munich, and he said to me that the USA was now wanting dialogue with Iran and Pakistan and Russian and…. and that this will be an initiative that will work … well I am glad he is so cocky about it. He then said ‘we have far more to fear from global warming than we have from international terrorism.’    What the hell planet is this guy ON?   It`ll take a 9/ll and the entire mad middle east to explode in their faces for the truth to dawn….. meanwhile, does it not occur to them that most of Western Europe has been trying to engage these countries in dialogue for the last 10 years – and that meanwhile, weekly, a terrorist plot is detected and defused by our counter-intelligence and  anti-terrorist police … He looked so smug I wanted to throw something at him.

Okay.  Politics over.  The all clear whistle has sounded.  It’s safe to go back into the water.

One of my readers sent me this great link to an article in the journal Archeology about the diet of the Roman gladiators.

It appears that far from being the cut and shredded specimens of masculinity that we see portrayed in films, the real gladiators were fat.  Why?  Because body fat protected them from injury.  It provided a kind of a built-in shield.  And how did the gladiators make themselves fat?  According to researchers on the subject, gladiators ate a lot of simple carbohydrates and not much animal protein.  I can already see Dean Ornish’s next book: The Gladiator Diet.

You’ve all read my whines and rants about the sorry press coverage of scientific studies.  Apparently I’m not the only one who feels this way.  Here is a writer from the prestigious British Medical Journal bitching about the same thing.

Says he:

Every day one of our national newspapers publishes a piece reporting on “scientific research” and nearly every day the report is misleading, inaccurate, shows poor understanding of science and scientific research methods, and irritates the hell out of many a hardworking researcher. Often the original research is crap too. Millions of innocent people are misdirected and confused as new and often harmful myths are started.

Couldn’t have said it better myself.

Last week an article appeared in the Los Angeles Times about intermittent fasting.  I’ve gone through quite an evolution myself on this subject, going from pro to not so pro back to pro with some reservations.  I’m planning a post within the next couple of weeks on the subject, specifically about one of the papers mention in this LA Times article.

A pretty good review article on the treatment of obesity appeared in Nature Clinical Practice Gastroenterology & Hepatology (free full text and pdf) last December. (See, my tabs have been up for a long time)  This article provides an overview of all the different diets available for the treatment of obesity.  And, what makes it nice, is that not only does it not ridicule or give the low-carb diet short shrift as most mainstream journals do, it actually seems to imply that the low-carb diet works the best.  Slowly but surely we’re making progress.

Last but not least, lets end with a death-defying bit of daredevilry.  Watch this guy jump this motorcycle both ways.  I like to push the envelope risk-wise sometimes, but you couldn’t get me to do this for all the money in the world.  Bravo!

Click here to view the embedded video.

My friend Tim Ferriss asked me to post an up to date version of my thoughts on intermittent fasting. I wrote a post about a year and a half ago on intermittent fasting that generated numerous comments and questions. Between then and now I’ve received many emails from readers who have gone on intermittent fasts, some with success, others with not so much. The early animal studies that looked so good prompted a number of researchers to look at intermittent fasting as a potential therapeutic tool for humans. I figured it was time for an update.

You can find my two part post on Tim’s blog.

Part I

Part II

I would be curious to hear from any and all who have given intermittent fasting a good solid try, so feel free to post your thoughts and/or results in the comments section.

I’ve posted on the health benefits of intermittent fasting (here and here) and on my thoughts on the inflammatory properties of food and overnutrition. These posts, particularly the one on inflammation, inspired a host of questions on whether intermittent fasting decreases inflammation. Based on my knowledge of the medical literature on inflammation and intermittent fasting I’m pretty sure that it does. A recent paper presents data indicating that it indeed does.

The April 2007 issue of Annals of Nutrition and Metabolism includes an article on the positive changes in inflammatory markers brought about by the intermittent fasting Muslims undergo during Ramadan.

As the authors put it in the introduction:

Intermittent fasting over a certain period of time is a feature of great religions all over the world and it is well known that nutritional habits, sleeping patterns and meal frequency have profound effects on maintaining human health. One of these fasting ceremonies is Ramadan. Ramadan is a religious month during which over one billion Muslims worldwide refrain from eating and drinking during the daylight hours for 1 month. The duration of restricted food and beverage intake is approximately 12 hr/day for 1 month, which makes Ramadan a model of prolonged intermittent fasting.

The authors are right in that Ramadan is a model of intermittent fasting with a host of subjects to pick from. I’m not sure that 12 hours of food abstinence a real intermittent fast makes, but it is a lot longer without food than the vast majority of us go for a month at a time. There is usually a pre-dawn meal that must be consumed before the sun rises and a post-fast meal that starts after sunset. I’m sure that Muslims don’t eat all night long during Ramadan, so I would venture that every 24 hours is made up of 12 hours without food, a few hours of eating before bedtime, sleep, then a meal in the pre-dawn hours. I would guess that there would be a total of maybe 5 hours during which people eat and 19 hours of each day in which they don’t. And for data gathering purposes, it’s nice that this schedule is maintained for an entire month. Since this fasting is a strong religious tenet for a group of people who take their religion very seriously, the data obtained from Ramadan fasting studies is probably much more valid than that obtained from typical volunteer subjects.

In this study 40 healthy, normal weight men and women aged between 20-39 years who underwent Ramadan fasting were compared with a group of 28 similarly aged men and women who did not fast. Data derived from questionnaires indicated that the majority of the fasting subjects ate their last meal between 1-2 AM and their first meal after the fast at around 6:30 PM, which means that most fasted for around 16 hours. (I assume that these subjects did not consume a predawn meal, eating late and preferring to sleep in instead.) The non-fasting subjects ate breakfast, lunch and dinner at regular times. Researchers collected twice-daily blood samples 1 week before Ramadan, during the last week of Ramadan, and 20 days after Ramadan.

Interestingly there was no difference in energy intake and no weight loss difference between the two groups. Apparently the fasters made up for lost time when they chowed down and ate as much as those who ate three squares throughout the day.

…average daily energy and water intake remained comparable in both the fasting and nonfasting group and the working hours of both groups did not change during the whole study. During Ramadan, in the fasting group, meals were taken exclusively at night while in the nonfasting group there was no change in the eating and sleeping habits. …the sleep pattern of the fasting group was delayed by approximately 2-3 h[ours] on average. The energy and the water balance seemed to be constant on a daily basis as the body weight and the 24-hour urinary volumes did not change during Ramadan. Hence there were two major changes in the routine of the fasting subjects: meal times and sleeping patterns.

What did the study show in terms of inflammatory response?

There were significant reductions in interleukin-6 (IL-6), C-reactive protein (CRP) and homocysteine during the fast that, in the case of IL-6 and CRP, lasted for at least 20 days beyond the fasting period.

What does this mean?

In short it means that the Ramadan intermittent fast brought about a significant decrease in inflammation.

IL-6 is a proinflammatory substance released by macrophages and other inflammatory cells that reaches the circulation and ultimately the liver. A number of studies have shown that about 30 percent of IL-6 comes from adipose tissue, especially abdominal or visceral adipose tissue (or more correctly, from the macrophages and other cells of the innate immune system that attack these fat cells). When IL-6 levels are high enough they stimulate the acute phase response in the liver. During the acute phase response the liver releases a number of proteins -including CRP- into the circulation. The job of these acute phase proteins is to prevent ongoing tissue damage, isolate and destroy the infective organism (or, in the case of visceral fat, the invasive organism) and activate the repair processes necessary to restore normal function. CRP is an acute phase protein that binds to certain sites on microbes, probably assists in the helping other parts of the immune system attack foreign and damaged cells, and enhances the consumption of these cells by the macrophages. CRP is an important player in the innate immune response, which is the blind, hardwired early responding part of our immune system.

Both IL-6 and CRP are elevated during inflammation, and both, but particularly CRP, are used as markers for inflammation. There is now a large amount of data showing that elevated CRP levels are a potent risk factor for cardiovascular disease.

The decreased levels of homocsyteine during fasting are an intriguing phenomenon. Homocysteine can react spontaneously with many biologically important molecules, especially proteins. It can react with and cause damage to the folding of important proteins, i.e., enzymes, immune proteins, receptors, growth factors, and structural proteins, leaving them with a configuration that is less than optimally functional. High homocysteine levels cause oxidative damage and are thought to cause inflammation, especially in the endothelium. As a consequence, elevated homocysteine levels are, like CRP, a fairly potent risk factor for cardiovascular disease.

Homocysteine is an intermediary in the metabolic pathway between methionine and cysteine, both important amino acids. Folate and vitamin B12 are essential in making the transition from methionine to cysteine without allowing large amounts of homocysteine to stack up. A deficiency of either folate or vitamin B12 (both B vitamins) allows an increase of homocysteine, which makes it’s way into the circulation and causes problems. What makes this study so interesting is that both folate and vitamin B12 levels increased substantially in the fasting subjects despite their not eating any more food containing these substances than the nonfasting subjects. It’s this increase of the folate and B12 that more than likely decreased the levels of homocysteine in the fasting subjects.

The authors speculate:

…both folate and vitamin B12 levels were increased in the last week of Ramadan in the fasting subjects and a negative correlation has been detected between these two vitamins and homocysteine levels. None of our subjects used any kind of vitamin supplements and according to the questionnaire, consumption of food containing B vitamins did not change during the whole study period. The changes in the rest-activity cycle and meal schedule during Ramadan may beneficially affect the bioavailability or redistribution of cofactors like B vitamins in the methionine pathway, which in return may lower plasma homocysteine levels. These results are consistent with [a] previous study in which homocysteine levels but not B vitamins were evaluated in the fasting subjects during Ramadan.

This ‘bioavailability’ and/or ‘redistribution’ is similar to that which happens with vitamin C during an all-meat diet. It is well known among arctic explorers that those on diets of nothing but fresh meat don’t get scurvy. The British sailors in the 1700s who were afflicted with scurvy consumed a diet composed primarily of carbohydrates. When British naval surgeon James Lind gave them fresh lime juice their scurvy was cured or prevented. As we all know now, the cure and prevention came about due to the vitamin C in the lime juice. Most researchers and physicians still believe that diets deficient in vitamin C will cause scurvy, but this isn’t the case, especially with fresh meat diets. The glucose molecule competes with the vitamin C molecule for entry into the cells. When glucose molecules are high – as they are in high-carb diets – much more vitamin C is required to compete with the glucose and actually make it into the cells. During all-meat diets, glucose is low, and a much smaller amount of vitamin C can still enter the cells and do its job.

Whatever the case, fasting reduces the levels of homocysteine, which is a very good thing.

Below are the charts showing the reduction of IL-6, CRP and homocysteine in the fasting subjects.

IL-6 Males

IL-6 Females

CRP Males

CRP Females

Homocysteine Males

Homocysteine Females

This study adds to the data showing that intermittent fasting does indeed reduce inflammation. Whether the reduction comes from the long period without food or from the change in sleep patterns the study doesn’t show. But I think it’s reasonable to assume that it is probably the former rather than the latter. Reduction in sleep time all by itself has been shown to be inflammatory, so I would guess that were these subjects to have maintained their regular sleep patterns and fasted fasted, they would have shown an even greater decrease in inflammatory parameters. But that is speculation; we’ll have to wait for the real data.

This paper confirms for me the idea of not eating between meals and not consistently snacking as some would recommend. I like to let things rest totally between meals and not nibble, even on low-carb snacks. Based on the intermittent fasting data that is rapidly accumulating, I think that eating as infrequently as possible is probably the best bet to keep your innate immune system behaving as it should, especially if you follow a higher-carb diet.

Anyone who is a regular reader of this blog will have noticed that the last post on intermittent fasting generated an enormous number of comments, just about all of which I tried to answer. Most of these comments were questions about intermittent fasting or people giving their dietary histories or people informing us that they were starting an intermittent fast. Other comments asked for answers to specific medical questions while others wanted to know if MD and I had abandoned the low-carb diet in favor of intermittent fasting. I figured that this would be a good time to set the record straight.

MD and I feel strongly that we as a species have a genome that was molded by the forces of natural selection over the past few million years to operate optimally on the food that was at hand during those few million years. What was available? Mainly fairly high-protein, high-fat fare. There weren’t a lot of carbohydrates readily available until the advent of agriculture a few thousand years ago. For the time that we developed our ancestors ate meat, fish, insects, clams, reptiles and pretty much anything live they could get their hands on. This primarily protein and fat diet was supplemented with whatever fruits, nuts, berries, roots, shoots and tubers were in season. Work done by Loren Cordain shows that, based on the Ethnographic Atlas, modern day hunter gatherers get about 65 percent of their calories from animals and the other 35 percent from plants. Most researchers believe that Paleolithic man got more than that from animals because during Paleolithic times many more large animals roamed the earth than do today. In fact, Paleolithic man hunted many of these large animals to extinction.

It is pretty safe to say that the macronutrients that set our genome were fat and protein. Many unenlightened people seem to believe that early man lived in land of carbohydrate abundance, and, consequently, thrived on a high-carbohydrate diet. It can easily be seen that this wasn’t the case simply by calculating how much food would have to be consumed to get enough calories from the available plant sources.

Taking 3000 kcal as being the average (it’s probably on the low side) daily energy intake of our Paleolithic ancestors and looking at how much plant food would be required to obtain those kcal is an eye-opening experience. I ran just a few foods through the USDA nutritional calculator and found that it would take 48 cups of blackberries–that’s 3 gallons of blackberries–to provide 3000 kcal. I don’t know how many readers have ever picked blackberries, but I have, and I can tell you that picking 3 gallons takes a lot of time. And, much though I love blackberries, I couldn’t come anywhere near eating 3 gallons of them in a day. How about blueberries? 36 cups; over 2 gallons. Spinach? 103 cups. Celery? 111 stalks. Apples? 42.

It was only after the advent of agriculture that calorically dense carbohydrate foods came into existence and became the common fare for man. Until then, our ancestors, if they were to subsist on plant foods only, would have had a pretty rough time of it getting enough without eating all the time. Which is exactly what the mountain gorillas do. Although mountain gorillas have the same carnivore GI tract that we do, early in their evolution (probably lead by the gorilla version of Dean Ornish) they opted for vegetarianism. These animals eat constantly to get enough plant food to meet their energy needs. They take food to bed with them so it will be available when they first awaken. They roam through the jungle throughout the day eating non-stop except for brief rest periods.

Given the above facts, it’s pretty clear that early man ate a fair amount of meat. After all, it takes only a couple of 16 ounce fatty steaks to provide 3000 kcal, which is a whole lot easier to down than 3 gallons of blackberries. It would then stand to reason that as a species we would perform better on a meat, or at the very least, a higher protein, lower carb diet since that’s what we had to eat for a few million years. In one of my favorite quotes, Dr. Blake F. Donaldson, a crusty old physician from New York who wrote a book called Strong Medicine, says:

During the millions of years that our ancestors lived by hunting, every weakling who could not maintain perfect health on fresh fat meat and water was bred out.

When we saw patients in our clinic for obesity and the other so-called diseases of civilization, MD and I successfully treated them with diets that approximated what we–based on the anthropological evidence–believed early man ate. We basically gave them the food they were designed by nature to eat. Obviously we couldn’t have them eating fresh mastodon steaks or cave bear fillets, so we had them eat the modern day equivalent (or as equivalent as it could get in the modern day) that could be found at the grocery store or in restaurants. We had to develop a diet that was palatable, not overly difficult to obtain and prepare, and that would allow them to live their regular lives and go about their business. After refining and tweaking, the diet we came up with is what we described in the book Protein Power. We diddled with it a little more and added a few supplements and made some more lifestyle recommendation such as getting more sunshine and getting rid of excess iron that went along with our Paleolithic origins and published the Protein Power LifePlan.

Since that time we’ve continued to think about the optimal diet and experiment with different permutations of the Paleolithic diet. We still believe that a low-carbohydrate, higher-protein, higher-diet is the optimal one for humans. In thinking about how to make a low-carb diet better, it dawned on us that there is another factor besides the actual food eaten in any particular diet: the timing of the eating. We began to think about how often Paleolithic man ate. We looked at data from modern day hunters and found that most of them didn’t eat all that often, and that when they did eat, they gorged.

Once we decided that meal timing was probably important in the development of our genome just as was the kinds of foods consumed, we started looking for evidence in the medical literature. There we came upon the studies on intermittent fasting (IF).

I covered intermittent fasting at length in the previous post. I was amazed that whatever goes on during the fasting process is potent enough to overcome the health negating effects of ad lib feeding because the animals that were underwent the IF had the same health benefits as did those that were calorically restricted yet the IF animals ate the same as the (ultimately sickly) ad libitum fed animals. And the IF animals lived as long as the calorically restricted animals despite eating as much as the much less long-lived ad lib fed animals.

Clearly something powerful takes place during a fast. What is the mechanism? Who knows at this point. But it’s something that should inspire a battalion of researchers to get busy looking into.

Now, based on the IF research data, MD and I are of the opinion that a Protein Power style diet interspersed with a little fasting is probably the optimal diet. We ourselves follow this diet. We eat one meal a day sometimes, a couple of meals others, and sometimes three squares. If we’re not hungry we don’t eat. We try to fight off the culturally induced feelings of, Oh, it’s lunchtime, so I must we must be hungry: let’s eat.

We tried the IF as written up in the post because we wanted to see if there was a particular regimen we could give people wanting to try it out. We know from many years of taking care of people on diets, that dieters want rules. The more we would write our material in such a way as to give patients (and readers) a lot of lee way in how they could prepare their low-carb diets, the more calls we got from these patients asking for us just to give them a set of meal plans. We found that the IF was easiest for us with a 6 PM cutoff; that’s why I described it that way.

There is probably no magic in the 24 hours; who knows, maybe it’s 15 hours. It just isn’t known at this point. I’m firmly convinced, however, that there is an advantage to going without food for periods here and there. I’m convinced for a couple of reasons. First, all the data on IF is pretty persuasive. Second, all the Ornishes, Barnards, Grundys and the other AOE (Architects of the Obesity Epidemic) recommend that we all eat a lot of small meals throughout the day. Given the track records of these people alone, it militates that we should eat large meals separated by long periods of time.

We still fully believe in Protein Power. We haven’t abandoned it in favor of IF. We have added IF to our own lives from time to time, especially if we go off the Protein Power wagon. But, we also IF using strict Protein Power, too, In short, IF is just an adjunct to the Protein Power diet that makes it work better by making it even more like the Paleolithic diet we cut our collective teeth on.

Once again I have to reiterate that I can’t answer specific medical questions over the Internet. Unless you’re my patient (and by that I mean someone who I have examined) I can’t tell you why you’re having this reaction or that. If your ankles are swelling, I don’t know why unless I can take a medical history and examine you. If you’re exhausted on the IF or any other regimen, it could be that you need a little potassium, or it could be something else. Whatever it is, I can’t give you an answer unless I take a medical history and do an exam.

One final note:

One of the commenters on the IF post is Robb Wolf who has worked with Loren Cordain and is himself well read on the literature of IF. He sent me an interview with Dr. Thomas Seyfried on ketosis and cancer that he said I could share with my readers. (click Download file to download the PDF) In the interview Dr, Seyfried discussed IF and some of its therapeutic uses. (You can also click here to read Dr. Seyfried’s paper on ketosis and brain cancer published this year in Nutrition & Metabolism)

Robb is the Editor-in-chief of the publication Performance Menu: Journal of Nutrition and Athletic Excellence, which contains articles on IF. (Click here to take a look)

How would you like it if I told you there was a way to eat pretty much anything and everything you wanted to eat and still maintain your health? Or better yet, what if I told you that you could eat pretty much anything and everything you wanted and even improve your health? Would you be interested? I figured as much.

There is a way to reduce blood sugar, improve insulin sensitivity, reduce blood pressure, increase HDL levels, get rid of diabetes, live a lot longer, and still be able to lose a little weight. All without giving up the foods you love. And without having to eat those foods in tiny amounts. Sounds like a late-night infomercial gimmick, but it isn’t.

Before I get to the real nitty gritty of how such a thing can be done, let’s look at a method that has been proven in countless research institutions to bring about all the above-mentioned good things. It’s called caloric restriction.

When researchers restrict the caloric intake of a group of lab animals to about 30 to 40 percent of that of their ad libitum (all they want to eat) fed counterparts, they find that the calorically restricted animals live 30 percent or so longer, don’t develop cancers, diabetes, heart disease, or obesity. These calorically restricted (CR) animals have low blood sugar levels, low insulin levels, good insulin sensitivity, low blood pressure and are, in general, much healthier than the ad lib fed animals.

Most of the work in caloric restriction has been done on rodents, but there is a long term study on Rhesus monkeys (17 years at this point) that appears to confirm the rodent data on longevity and health with CR in primates. There are no human longevity studies, but there are a number of human studies on CR and health that show that human subjects under CR conditions reduce blood sugar, improve insulin sensitivity, reduce blood pressure, etc., so it stands to reason that if humans reduced their caloric intake by 30-40 percent for their entire lives, they would also live longer.

Caloric restriction is a terrific way to lose weight and get healthy; problem is, it’s not much fun. When rats live out their little ratty lives calorically restricted in their cages they seem to show signs of depression and irritability. Primates do for sure. If primates don’t get enough cholesterol, they can actually become violent. But, if you’re willing to put up with a little irritability, hostility and depression, it might be worth cutting your calories by 30 percent for the rest of your long, healthy miserable life.

Doesn’t sound so cheery? You’re not ready to sign up yet?

Well, there is a better way.

A number of different research teams have studied a method by which rodents can get all the health and longevity benefits of caloric restriction without calorically restricting. And the method has been studied in humans and seems to achieve the same health benefits and, if an old Spanish study can be believed, maybe even an increase in lifespan.

What is this magic method?

Intermittent fasting.

In regular fasting one goes entirely without food, which is caloric restriction carried to the extreme. Going entirely without food in the short term leads to improvement in health, but also leads to an extremely short life unless the fast is aborted.

Intermittent fasting (IF) is just as its name implies: a period of fasting alternated with a period of eating.

But isn’t that what we do anyway? We eat breakfast, then fast until lunch. Then, after lunch, we fast until supper. Then we fast all night. Uh, not exactly.

In research settings animals that are intermittently fasted are fed every other day, so they eat whatever they want for a day, then they are denied food for a day. Interestingly, on feeding days most of the animals eat a almost double the amount that their ad lib fed mates do. Thus the IF animals eat about the same number of calories overall that the ad lib fed animals eat, but, and this is a huge ‘but,’ the IF animals enjoy all the health advantages that the CR animals do, and, in fact, are even healthier than the CR animals.

Like caloric restriction, intermittent fasting reduces oxidative stress, makes the animals more resistant to acute stress in general, reduces blood pressure, reduces blood sugar, improves insulin sensitivity, reduces the incidence of cancer, diabetes, and heart disease, and improves cognitive ability. But IF does even more. Animals that are intermittently fasted greatly increase the amount of brain-derived neurotrophic factor (BDNF) relative to CR animals. CR animals don’t produce much more BDNF than do ad libitum fed animals.

What’s BDNF? (The Wikipedia definition is actually pretty good)

BDNF, as its name implies, is a substance that increases the growth of new nerve cells in the brain, but it does much more than that. BDNF is neuroprotective against stress and toxic insults to the brain and is somehow–no one yet knows how, exactly–involved in the insulin sensitivity/glucose regulating mechanism. Infusing BDNF into animals increases their insulin sensitivity and makes them lose weight. Humans with greater levels of BDNF have lower levels of depression. BDNF given to depressed humans reduces their depression. And Increased levels of BDNF improves cognitive ability. In short, you want as much BDNF as you can get., and with IF you can get a lot.

But, who wants to go all day every other day without food?

Well, you don’t have to. MD and I, using ourselves (selflessly, I might add) as subjects have worked it out.

Most rodents feed throughout the day and night, so restricting them for 24 hours does just that: it restricts them for 24 hours. In humans, however, the situation is different. We humans, for the most part, eat only during our waking hours. So if we fast for a day, we end up fasting for about 34 hours and eating for 14, which isn’t the same as 24 on, 24 off.

Let me show you what I mean.

Let’s say you pick a day to start. You eat all day, then go to bed, wake up in the morning and fast all day, then go to bed. You wake up the next morning and eat all day, then go to bed and start again. So, assuming you eat until 10 PM on your eat day, once you quit eating you don’t eat again until 8 AM 34 hours later. If you eat from 8 AM that day until 10 PM, you’ve eaten for 14 hours. so, you’re on (eating) for 14 hours and off (fasting) for 34. MD and I spent a couple of weeks doing it that way, and I’m here to tell you, it’s no fun. At least not on the fast days. The eating days were a different story; they were great, but we would spend the entire day dreading the fast day coming up.

We fooled around with a number of different eat-fast-eat regimens and came up with something that works pretty well. We set up our cutoff time as 6 PM. On the day we started, we ate until 6 PM, then fasted until 6 PM the next day. On the next day we ate supper right after 6 PM and ate breakfast and lunch (and a few snacks) the next day until 6 PM when we started fasting again.

The advantage of this regimen is that we were able to eat every day. One day we would get supper–the next day we would get breakfast and lunch. On no days would we go entirely without food. This schedule worked the best for us.

On the times during the day that we ate, we didn’t stick with our normal low-carb fare; we ate pretty much whatever we wanted, including a fare amount of higher carb stuff. We stuck with the regimen for a few weeks just to see if we could tolerated it, which we did just fine. We ultimately drifted back to our normal low-carb diet, however, just because it seemed to work better with our schedules. We could have been happy on the intermittent fasting regimen for the long term.

I would think that the optimal way to go would be to follow an intermittent fast using low-carb foods during the eating periods. One would get the best of all worlds healthwise this way.

Over the period that we followed the various IF regimens we lost a little weight because, unlike the rodents, we couldn’t eat twice as much during the eating days as we would have eaten were we not fasting. We didn’t check any lab work to see if any values had changed. We weren’t doing a hard core study; we were simply evaluating IF as a practical means for humans to use to improve their health.

In thinking about the process I came to the conclusion that IF was probably the way Paleolithic man ate. We modern humans have become acculturated to the three square meals per day regimen. Animals in the wild, particularly carnivorous animals, don’t eat thrice per day; they eat when they make a kill. I would imagine that Paleolithic man did the same. If I had to make an intelligent guess, I would say that Paleolithic man probably ate once per day or maybe even twice every three days. In data gathered from humans still living in non-Westernized cultures in the last century, it appears that they would gorge after a kill and sleep and lay around doing not much of anything for the next day or so. When these folks got hungry, they went out and hunted and started the cycle again.

If you buy into the idea that the Paleolithic diet is the optimal diet for us today because it is the diet we were molded by the forces of natural selection to perform best on, then you should probably also buy into the idea that a meal timing schedule more like that of Paleolithic mean would provide benefit as well.

One of the things MD and I took away from our IF experience is the idea that we don’t have to eat three meals per day. We now often skip lunch and don’t seem any the worse for it. Sometimes we get up and get going with all our projects and don’t eat breakfast. We try to skip a meal here and there because figure it’s probably good for us. When you get used to it, you don’t really even think about it. And it’s good for you. Don’t take my word for it–look at the medical literature.

There have been a few human studies on IF, and all have shown a marked improvement in virtually every parameter tested. None of the subjects in any of these studies has done the full 24 on-24 off that MD and I did. Most fasted until 5 or 6 PM on the fast days, then ate, then ate regularly on the eat days. Even with this wimpy IF schedule the subjects did better.

One of the recent papers published on the less rigid IF schedules caught my eye because one of the authors was Don Laub, who used to be the chairman of the plastic surgery department at Stanford. When I was in medical school I thought I wanted to be a plastic surgeon so I went to Stanford during a part of my senior year and worked with Dr. Laub as my mentor.

In this study, published in the journal Medical Hypothesis in March of this year, Dr. Laub along with two other physicians (neither of whom I know) underwent their version of and intermittent fast. The three of them have since May 2003 been on a version of the IF in which they consume about 20-50 percent of their estimated daily energy requirements on the fast day and eat whatever they want on the non-fast days.

Since starting their regimen they have

observed health benefits starting in as little as two weeks, in insulin resistance, asthma, seasonal allergies, infectious diseases of viral, bacterial and fungal origin (viral URI, recurrent bacterial tonsillitis, chronic sinusitis, periodontal disease), autoimmune disorder (rheumatoid arthritis), osteoarthritis, symptoms due to CNS inflammatory lesions (Tourette’s, Meniere’s) cardiac arrhythmias (PVCs, atrial fibrillation), menopause related hot flashes.

In their paper these researchers discuss a 1957 paper from the Spanish medical literature.

…the subjects were eating, on alternate days, either 900 calories or 2300 calories, averaging 1600, and that body weight was maintained. Thus they consumed either 56% or 144% of daily caloric requirement. The subjects were in a residence for old people, and all were in perfect health and over 65. Over three years, there were 6 deaths among 60 study subjects and 13 deaths among 60 ad lib-fed controls, non-significant difference. Study subjects were in hospital 123 days, controls 219, highly significant difference. We believe widespread use of this pattern of eating could impact influenza epidemics and other communicable diseases by improving resistance to infection. In addition to the health effects, this pattern of eating has proven to be a good method of weight control, and we are continuing to study the process in conjunction with the NIH.

There is much more to the IF story that I will continue in another post. I would do it in this one, but I (actually my web guy) upgraded my blogging software and somehow the little buttons that let me link to other sites are AWOL. I can’t italicize or set off quotes or do any of the things I normally do in the course of posting. I’m hoping that I will get this straightened out soon. When I do, I’ll go into the subject in a little more detail and show a chart that demonstrates the difference between CR and IF. (Note: the problem is solved; all links are working.)

In the meantime, if any of the readers of this blog would like to undertake an intermittent fast, I would love to hear the results of the experience. Please send a comment.