Tuesday, May 24, 2011

Into the Depths of Nutrition Science

It all started in my senior year of college. It can be questioned how much I learned in my four years as an ORFE major at Princeton, but what is indisputable is that on April 30, 2008, my world changed forever. On that particular Wednesday, Tim Ferriss of The 4-Hour Workweek and The 4-Hour Body fame was the guest lecturer in my entrepreneurship class. As I walked out of that lecture hall, I could think about nothing more important at that moment than for me to get back to my dorm room and order 4HWW on my original kindle. It wasn't long before I realized that Tim had my dream life. Funny thing is, I didn't even know what my dream life was until I heard him describe it in his lecture.

Fast forward a year, Tim posts this article by Dr. Mike Eades on his blog about saturated fat. Hrm, interesting. A couple months later, Tim posts this article by Gary Taubes. In it, Tim calls Gary's book Good Calories, Bad Calories the "definitive" work on nutrition. From someone like Tim, that is VERY high praise, praise that I take extremely seriously. A couple of weeks later, a video I saw of Anthony Johnson touches on similar points about carbs and fat, and also talks about exercise science, and in particular the book Body by Science. I buy it on my kindle and start going through it. In the book, Doug McGuff talks about nutrition, and references these similar "animal fats are fine, carbs are problematic, humans evolved as hunter-gatherer" sentiments. On Sunday, November 1, 2009, the day after Halloween, I decided that I was going to get freaking jacked while losing bodyfat on a Body by Science routine and a low carb diet. I also purchased GCBC on the kindle and read it.

The theory that Gary put forth in his book is that insulin is the primary hormone responsible for fat storage, and that insulin is secreted by the pancreas in response to carbohydrates in the diet, so it would make sense that carbohydrates make us fat. It explains the effectiveness of low carb diets, and it creates a good story about how we as a society got fat over the last 30 years despite being lean for the most part prior to that. It explains why diabetics cannot store fat without insulin injections, and why most people who are extremely overweight have muscular insulin resistance. There are some unexplained phenomena, but I was in denial about those at the time.

Did the low carb thing for a while, lost a lot of body fat, saw some small muscle gains, but not the Geek-to-Freak gains I was hoping for. Oh well, I'm still a work in progress on the muscle gaining front, tweaking routines and supplementation as I see fit, although I have about 20 extra lbs of lean mass now as compared to then. Still, the takeaways from this period of my nutrition education are clear: saturated fat and dietary cholesterol don't cause heart disease, all diseases of civilization are preventable through lifestyle changes, my illness, systemic scleroderma, was caused by my taste for pasta, and people don't get fat because they eat too much and don't exercise enough, they get fat because of the quality of the food that they eat. All you diet agnostics (I'm talking to you Brad Pilon) are wrong about the quantity vs. quality debate.

At some point, my low carb world-view came crashing down. Bloggers in the "paleo" community started talking about the Kitavans and their high carb life, Stephan Guyenet and Mark Sisson endorsed potato consumption for lean individuals, Robb Wolf had already been preaching about the virtues of sweet potatoes forever, and Paul Jaminet was writing about zero carb dangers and calling white rice a "safe starch," Maybe the carbs aren't the problem? Maybe it's specific elements in the food, in particular Kurt Harris' "neolithic agents of disease,"  wheat, excess fructose and excess omega-6 fats. I was in this camp for a while before I really understood the mechanisms, so I was straddling the low carb and paleo worlds unable to reconcile to two. Enter leptin.

Leptin is produced by adipose tissue roughly in proportion to the fat mass on the body. This signal gets interpreted in the hypothalamus, and when it reaches a certain threshold, eating more becomes very difficult. Like body temperature, fat mass is regulated within a very tight range in the hypothalamus, and when overeating and undereating, the body will defend against changes to this fat mass, even in overweight individuals. Your metabolism doesn't "break," it is still working properly, it's just not regulating body fat mass at a healthy level or at least at the level you want it to. In obese individuals, this level or "setpoint" that the hypothalamus aims for is either changing or remaining the same while the leptin signal that is interpreted by the brain is weakening for the same amount of leptin, known as leptin resistance.

This negative feedback loop between the adipose tissue and hypothalamus via leptin signaling makes sense. It's validated by the data. If inflammation is disrupting the signaling, this would explain why paleo diets work. My world makes sense again. Anti-predation proteins in plant seeds (grains and legumes) inflame the body, this inflammation inhibits leptin signaling, and this inhibited leptin signaling causes us to eat more. This is pretty much were I stood when Dr. Harris put out his series about how there's no such thing as a macronutrient, Part I here and Part II here, as well as when he published his post entitled Paleo 2.0, A Diet Manifesto.

This theory was put into practice by my dad when he set out to lower his cholesterol and get off of Lipitor toward the end of last year. My dad, who was already pretty lean, went grain, legume, and dairy free between Thanksgiving and Christmas of 2011. In the intervening four weeks, he lost 15lbs, or nearly four pounds per week (a number which the Calories-In/Calories-Outers would call impossible for a lean individual). After Christmas, he lost another 5+lbs before his weight stabilized. It's proof of concept, at least in that n=1 experiment. Still, this wasn't the end of my learning. Thursday, April 28th, 2011, my world-view with respect to nutrition and adiposity would be shaken again.

On his blog, Stephan posted this article, which talks about a study in which rats get fat eating chocolate Ensure but not vanilla or strawberry Ensure. W-T-F? How can chocolate Ensure be more inflammatory than the other flavors? Well, it can't. But Stephan is proposing a new mechanism, one involving food reward changing the setpoint. How? In Stephan's words in response to a question of mine about food reward being short term vs long term:

Food reward is heavily intertwined with the dopamine-secreting regions of the brain, the VTA and substantia nigra. These regions project to the hypothalamus, the region that seems to encode the setpoint, and we know that dopamine modulates the activity of that region. Reward is not inherently short term, although it has a short term component. Reward-related behaviors change over time as an animal becomes habituated to highly palatable food, and they end up resembling a drug addiction state in some ways.


Another piece of the puzzle. So now we have two mechanisms by which leptin signalling fails: inflammation, which is caused in large part by diet, and food reward, which is primarily caused by food manufacturers creating the processed foods to specifically be hyperstimulating to the food reward system. Inflammation interferes with the leptin signalling, and food reward upregulates the setpoint (Stephan defines food reward more specifically in the comments here).

In this model, fast food/processed food is the perfect storm of obesity creation because it is both highly rewarding and inflammatory. Part of the blame needs to lie on us as the consumer. Every time we buy these super satiating foods, we are voting with our dollars for their production. Still, we can't place all of the blame there. These foods are artificially cheap because of government agricultural subsidies to the tune of $0.62 for every $1 or a total of $180 billion in 2009. We have a government that is pushing a high grain, low saturated fat diet AND subsidizing it with our tax dollars/national debt. Big Agro certainly got their moneys worth on those lobbyists. Of course it wouldn't be a good conspiracy theory without the Oil Lobby or Pharma Lobby being involved. These crops are grown with fertilizers created from fossil fuels, which represent the the overwhelming majority of governmental energy subsidies as compared to sustainable energy. And of course, as we've stated earlier, these subsidized foods are the ones that are making us sick, so it's definitely in the interest of pharma and health insurance companies to support these policies, whether they do so overtly or not.

Still think the government has your best interest at heart? The American government is sold to the highest bidder. My generation, those of us in our early to mid 20s, is going to take it back.

3 comments:

  1. glad to see Americans are (finally) looking into the difference between grains. btw I never get the crave for pasta/pizza/hot pocket/calzone, they are essentially the same awful stuff.

    I agree conAgra, Tysons and others are lobbying otherwise their packaged frozen goods cant be that cheap all the time.

    -Meng

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  2. "We have a government that is pushing a high grain, low saturated fat diet AND subsidizing it with our tax dollars/national debt."

    What you don't realize is that both of these things stem from government claiming the right to initiate force against individuals when subject individuals has violated the rights of no one.

    When that shit ends, the world will be a better place, literally, in the sense that fiat money would be a thing of the past, and any "tax" that was involuntary. Property, income, or otherwise.

    Attack the source not the symptom.

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  3. Hey Anthony,

    I'll get into political theory in a future post, but for now let's just say that this is the fundamental point that you and I disagree on.

    I believe that the government is not an entity separate from the people, but rather an entity created and owned in whole by the people with the sole purpose of being a monopoly on force. The idea behind creating such an entity is to remove the threat of violence from our day-to-day lives.

    You and I both have the option to opt out at any time by leaving the country, but as long as you live in the United States you are voluntarily choosing to enter into a contract with the government to abide by its laws.

    Thanks for commenting!

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