Right now I am stuck in my book. I am trying to write about Calories and obesity without actually talking about dieting to lose weight. I want to focus on the ecological implications of excess Calorie consumption and the unique microbial ecosystem that obese people have in their gut. But I keep getting derailed. I have to admit that I have fully assimilated society’s paradigm that the only way to talk about fat and Calories is how to lose one and restrict the other (without depriving yourself of course). And damn it if I don’t have those five or so nasty pounds I need to lose in order to “get that beach body.”
While I was researching this part of my book, I told my mind to turn that nagging “you need to be skinny” part off. I am a scientist. I can be analytical. I can focus on the theoretical implications of these studies rather than how they can take a dimple of fat off my ass—ooh, is that a study that validates the chips and salsa diet!!!???
Apparently, I can’t. As I looked through one scientific paper after another, my mental ears kept perking up at the suggestion of the One Thing we can eat that would be the uber health magic bullet.
And then we all eat chia seeds and live happily bikini-bodied ever after.
Or in the actual science literature:
Though how you’d get access to any of these in a magic bullet form if you aren’t a lab mouse is anybody’s guess.
The thing is there is no magic bullet food or compound. If we remove the Western diet from our figuring (even though it’s a huge pink elephant in the room, it’s a relatively new elephant), we find an amazingly disparate number of diets that convey health to its eaters. As biochemist Harold Draper (no relation to Don) says about the Inuit diet of primarily seal fat, “There are no essential foods–only essential nutrients. And humans can get those nutrients from diverse and eye-opening sources.”
However, if we now acknowledge the pink elephant of the Western diet, my research into current scientific literature is showing that perhaps WHAT we eat may not be as important to our gut health and micro-ecology as HOW MUCH we eat.
Self-control? I don’t like that idea at all.
Remember Morgan Spurlock’s epic Supersize Me documentary? When I used to teach English Literature, I showed that movie every semester to my students. Spurlock embarks on a 30-day McDonald’s-only eating experiment that ends up almost killing him. His argument makes intuitive sense: eat crappy food, you will be unhealthy. And that movie (along with Eric Schlosser’s Fast Food Nation and the film Food Inc) has indeed triggered some much-needed changes (however small) in how we market and view fast food. However, there are other–perhaps edgier–voices out there that claim we can have our fast food and be healthy too. There are actually quite a few examples of people who set out to prove Spurlock and Co wrong which included Julie Dove’s My McDiet movie and various fast food diet books. The thing is that these people do seem to improve their health on fast food … through Calorie restriction (caveat: the parameters of health in these pop culture movies and books are human metabolic markers like insulin sensitivity and cholesterol. These things do have some connection to our microbiota but still it isn’t as simple as saying “good cholesterol equates to a healthy gut ecosystem.” But read on . . .).
Let me restate those last two words because you might have lost them in my aside:
How much we eat matters as much as what for both our human health as well as our microbial health. Actual scientific research (as opposed to anecdotal documentaries) confirms this premise. Mice and humans who lost weight on a Calorie restricted diet experience a shift in their microbiota towards a population with more diverse functions which seemed independent from what they ate as long as they lost weight (the papers do argue that it isn’t Calorie restriction per se that leads to the weight loss, but what is it then?). Cells that experience a decrease in available energy (and severe stress) appear better at taking out the toxic trash that builds up inside than those who experience extended periods of energy glut. People who have gastric bypass surgery experience an increase in insulin sensitivity and other health benefits. Not because any of these are accessing a magic bullet compound but because they are all getting less energy. Fewer Calories are available and the system seems to thrive. The list goes on and on and many studies are still looking at the long term affects of Calorie restriction on health.
It is as simple as Calorie restriction equates to better health and then again not quite that simple.
Science is not an exact science. Which is why I love it and why it makes such a bad boyfriend.
It is argued in a recent and seminal paper that gastric surgery leads to changes in gut microbiota that is independent of Calorie consumption (and when the new post-surgery microbial population is transplanted to non-surgery mice, they also experienced the weight-loss benefits without changing their diet). Fair enough. It could be that the changed topography of the gut is what actually drives the microbial population shift from that of an obese profile to one that is different. Other research on the gut ecology of different types of stomach structures and diet has shown that microbial population does seem to be specific to the gut structure.
However, the authors of the gastric bypass mice research do allow that this type of surgery does decrease the net energy available from diet and increases net energy expenditure (sound similar to diet and exercise to anyone else?); further, they point out that the results of the surgery were similar to that of dietary restriction. So, it could be argued that “decreased energy available” is mighty close to “Calorie restriction” aka “decreased energy consumed.”
We need to eat. That is something we can’t get around because we need to feed our expensive big brain. But how much energy becomes too much?
In 2000, the USDA determined that the average American had access to 3,800 Calories per day. After accounting for food wasted or thrown away (1,100 Cal), it claimed that American’s ingested, on average, 2,700 Calories of food energy each day–a 24% increase in food consumption since 1970 . In this same report, most Americans surveyed expressed great concern over what they ate, but none at all about how much they ate.
Around WWI, we developed the commercial fertilizer. Using scientific methods, we perfected the best combination of nitrogen, phosphorus, and potassium to cause plants to grow big fast. It is only now that we are realizing that growing big fast isn’t the same as thriving.
The Western diet is the human equivalent of fertilizer: with its various nutrient fortifications, it has all the stuff we need on paper but doesn’t quite equate to thriving. Scientist Peter Turnbaugh describes the energy-saturated obese gut ecosystem as “a fertilizer run off where a reduced diversity microbial community blooms with abnormal energy input.” We are very very good at growth. Look at how fast we can get livestock to slaughter with the right foods and antibiotics. But growth is not health. We need to see what happens to that growth over time. And so far, time is proving not to be our friend in this matter.
The nutrition industry examines the what we eat a lot and rightfully so. I agree that what is important. I will always advocate a kale salad over a jelly donut and implement a diet of whole and fresh foods in my house. But we shouldn’t discount paying attention to quantity as merely the archaic “calorie counting” and not helpful to our overall health.
The sad news is that we didn’t evolve to be able to eat whatever we want all the time in any amounts. We have no internal safeguards against that type of energy exposure (though we have a ton of internal mechanisms to protect against famine). Evolutionarily, we don’t care about how much we eat because until recently (and still current in much of the world), we have had external stops to how much food energy we have access to. The problem was never stopping but how to get that rare and much-needed energy for our big brains and how to effectively store it against future times of famine.
I don’t want to slip into talk about diets because this post isn’t about a diet (just like my book chapter isn’t). But I will add that a lot of those diets whose practitioners see health results have external Caloric restriction even if they aren’t touted as that. We don’t (as much as we know we need to) get up from the table when we are full (ever wonder why it takes 20 minutes for your stomach to register fullness to your brain?); we keep eating because that is what every cell in our body is screaming at us to do. Diets that “work” have external stops whether is it chewing a million times. Or eating things that are “bulky” and literally fill your stomach. Or using a smaller plate to put less food on it.
There are some awesome studies out there about WHAT we eat and how it affects our microbes (I am participating in one for the American Gut Project), but they don’t really address or compensate for Calorie differences (or energy availability differences). I would love to see a study that actually addresses that idea. Perhaps it is out there lost in the chaos of the interwebs, I just haven’t found it yet.
All this to say, there is no WHAT magic bullet to make us healthy with better microbes. It still boils down to conventional wisdom of diet (HOW MUCH) and exercise. Damn that need for self-control.
However, maybe there is a physical magic bullet out there: maybe it’s Roux-en-Y gastric bypass, but I’ll be there are a few of us out there unwilling to undergo major surgery for it.
Now a shit enema from research mice . . . that’s a whole ‘nother thing.