|Nutrition is Science, not opinion.|
So, I had another Thanksgiving post in mind, but I'm going to save that one for another day. I have a little bee-in-my-bonnet about a few things that have come across my lab bench these past couple of weeks. Given that we are approaching a holiday that is entirely about eating, I thought it would be as good a time as any to discuss the apparent disconnect in the public between nutrition and sound science (something you all know I am a little fanatical about...). A couple of weeks ago, I posted an article on my FB page written by Dr. David Katz, M.D. He blogs pretty often for the Huffington Post and he wrote this interesting piece called "The Raw Food Diet, Overcooked". Basically, his premise was that, despite the very obvious benefits to eating a largely plant based raw diet, there were also some misconceptions within the raw movement that disregarded some of the science we know as fact.
|Photo Courtesy of vegan-raw-diet.com|
An interesting point he makes is, "All too often, opinions about nutrition are disseminated with religious zeal, as if gospel...Nutrition IS science...We tend to honor this implicitly in almost every science but nutrition. Unsubstantiated opinions about how to build a suspension bridge, perform neurosurgery, or accelerate atoms are of no particular interest. We recognize in these disciplines that expertise matters...Somehow, though, we make an exception for nutrition." A friend shared my post on his own page, and one of the comments that it received was, "Nutrition is chemistry (as biology is mostly applied chemsity [sic], which is in turn applied physics). That said, I was under the impression that understanding the nuances of nutrition is still not wrapped up in a tight formula. There's still holes and gaps in how nutrition theory works. Or am I wrong?" Well, friend, you're right about the first part. But, here's the thing...no science is "wrapped up in a tight formula". Go ask Dr. Neil deGrasse Tyson if the science surrounding theories in astrophysics are all "wrapped up". Ask Dr. James Hansen if he's got climate change completely figured out. Ask the particle physicists that discovered the Higg's Boson (God Particle) while working at the Large Hadron Collider if they've settled that whole quantum mechanics thing.
|Great Scott!! 1.21 Gigawatts??!!|
Let me save you the time (although you should definitely check out their work, it's all amazing). They don't have all the answers. No scientist does. It's WHY we do what we do. We have questions. And the answer to one question leads to another question. And so on...to ∞. One of my favorite quotes is "The most exciting phrase to hear in science, the one that heralds the most discoveries, is not "Eureka!" (I found it!) but 'That's funny...'” -Isaac Asimov It's true, scientists do have ongoing questions about nutrition. But there is a pretty solid understanding of what food does in your body. Unfortunately, with nutrition, the factual science often gets lost in the messaging. Perhaps because everyone eats every day, people feel like they ARE experts. They KNOW what foods make them feel good or bad, which they are allergic to, which make them gain weight or help them shed a few extra pounds. They're not really sure why these things happen to them with food, it just does. But the thing is, what's actually going on in your body is less of a mystery than everyone tends to think. Part of the problem comes into play with the types of studies that examine nutrition (actually that happens in most biologic sciences). We have (generally) three types of studies: population, individual, cellular. Population studies show associations, which tend to be extended into assumptions (i.e. Americans are eating more carbohydrates...Americans are getting fat...Therefore, carbohydrates must be making people fat). Unfortunately, these studies are more often than not, the end-all for media and food industry messaging. When, in the scientific world, these studies are really only useful as very general roadmaps - guiding researchers on where to look.
In fact, when you do drill down a little further, you see that your original assumption about carbs may not be the whole story. When you actually feed humans carbohydrates, they don't get fat, unless they eat too many of them (as it turns out, you can even eat a diet of Twinkies and not gain a pound if you don't eat too many...I know, don't even get me started...). And when you look a bit deeper, you can actually see the very specific things that happen to these carbohydrate molecules as you chew, swallow, absorb, and transport them into tissues.
|This is a simple diagram of the absorption of carbs...there's a lot more going on once they're in...|
You can even go FURTHER into the cell, and see how these tiny carbohydrates are able to affect your genes - like, literally how they bind to each other. You can then trace the proteins that your RNA translates after your genes have been stimulated to see which other "signals" are turned on or off...all from interacting with that little carbohydrate. So, this discovery process leads to a billion more questions (literally a billion...more than a billion...a ba-jillion). Because then, we can isolate specific cells in the lab from each tissue type (i.e. muscle cells, fat cells, liver cells, old cells, young cells, sick cells, healthy cells, etc) and start adding or witholding nutrients to isolate which pathways are activated in each specific state. Think of this this way...you walk into an unfamiliar dark room and feel for the light switch on the wall. You find the switch, which is actually a panel of eight switches. So, you have to start flipping them on and off, one at a time, until you find the one that turns on the light. Then, you decide that you also want the ceiling fan on, so you start the process again until you get the perfect combination of switches that keeps the light on and the fan whirring.
That is what we are doing in nutrition science right now. We are literally making models of cells in a petri dish to purposefully turn on and off switches. We are way beyond "Do carbohydrates make me fat?" We are now looking into, "How exactly does this particular carbohydrate (there are several) affect this particular gene (there are tens of thousands) in this particular person (there are now >7 billion)"? And this is why nutrition SCIENCE is so important (and yet so difficult to translate into mass media). Everyone has a specific set of genes. It's why you may be deathly allergic to peanuts, but the rest of your family could snack on the nuts in the bowl on the bar all night. In general, our bodies respond to food in a pretty similar fashion, but it's the important details - mostly about diseases and disorders - that we are working out. And here's the thing...the facts are not sexy. There is no magic diet. Most of the diets out there DO ignore science, or cherry pick snippets that suit their predetermined conclusions (I'm looking at you, Master Cleanse...).
In the end, there is no panacea. There is only food. REAL food. There is food that is generally good for you (like vegetables...you should eat a lot of these) and there is food that is generally not so good for you (like saturated fat...although, to be fair, only in excess...so only eat a little). Then, there are food-like products (like Twinkies...you should never eat these...seriously, even scientists don't really know what's in those things).
|37 ingredients in total...bleh.|
If you're confused about what to eat, it's not because science is confused. It's because the people interpreting and blaring the messages are confused. It's because the food industry wants you to be confused so they can continue to sell you crap-in-a-box. It's because celebrities and their know-nothing trainers are trying to get you to pay attention to them. It's because fill-in-the-blank "expert" wants to make a million dollars on a book touting an amazing new diet where you eat only snozzberries juiced carefully into mystical water from a secret spring in Asia (I made that up, it doesn't really exist...yet). Don't be confused. Nutrition IS science, but it really isn't that complicated when it comes to what you put in your mouth. Put REAL food on your Thanksgiving table and be grateful for how biologically equipped your body is to make use of it. Then, based on the laws of physics, you probably can't actually burn all the calories you will consume (~4500kcal), so you should probably plan to go for a run...