21 Eylül 2012 Cuma

Nutrition Science Initiative (NuSI)

Some of you may have heard of an ambitious new nutrition research foundation called the Nutrition Science Initiative (NuSI).  In this post, I'll explain what it is, why it matters, and how I feel about it-- from the perspective of an obesity researcher. 
What is NuSI?
NuSI is a nonprofit organization whose stated goal is to "facilitateand fund experimental research in nutrition with the goal of reducing theeconomic and social burden of obesity and obesity-related diseases."  In other words, its goal is to understand obesity more thoroughly so it can be prevented and reversed more effectively.  NuSI was founded by Dr. Peter Attia and Gary Taubes, and is funded by the Laura and John Arnold foundation and other sources.  Dr. Attia is primarily responsible for running the organization, and he's also the author of the blog The Eating Academy. 
NuSI is attempting two main things at this point: 1) bring together top scientists; 2) give them the funding to do ambitious research that has never been done before, or test questions more rigorously than they have been tested previously.  I can attest to the fact that they're accomplishing goal #1.  Dr. Attia has told me who they've involved at this point, and it includes some of the top scientists in obesity research-- people who I strongly support.  Whether goal #2 happens remains to be seen, but if everything goes according to plan, NuSI may end up being a major new funding mechanism for obesity research.  Apparently, the potential for funding is significant enough that NuSI has been able to draw the attention of certain senior researchers.
Why I Support NuSI
Dr. Attia and Taubes have asked for my support on this project.  As everyone reading this knows, I've had high-profile disagreements with Taubes.  Dr. Attia and I have had a few positive exchanges, and although I don't know him well, he strikes me as a reasonable and constructive person.  Both of them are proponents of the low-carbohydrate diet, and they have both had personal successes with this eating style.  Dr. Attia also has clinical experience with diet, including but not limited to low-carbohydrate diets.
NuSI is proposing major funding for some very ambitious experiments that have never been conducted before.  I'll let Dr. Attia give more details on this, but suffice it to say that the project could be very exciting if it materializes as planned.  
So the question arises, should I support an organization that's run in part by a person whose approach to scientific inquiry I disagree with?  It would be remiss of me not to question the wisdom of putting a major science funding mechanism into the hands of a journalist who is, shall we say, very attached to his ideas.  To put my conscience to rest, I contacted Dr. Kevin Hall, an obesity researcher who is acting as lead scientist on this initiative.  He explained to me that NuSI will have no control over research design, conduct, or reporting, and in fact he's contractually obligated to the National Institutes of Health not to allow NuSI to have any control over these things.  So although NuSI will get to choose what experiments it funds, it has no control over what happens after that, and so its potential to compromise research integrity seems low.
I may not always agree with NuSI's funding priorities (although I suspect I often will), but the bottom line is that it will increase funding for top scientists in a tough economic/political climate, potentially make experiments possible that were formerly inaccessible due to excessive cost, and add to human knowledge about diet and health.  That's why I support it.
My Concerns about NuSI
NuSI was organized ostensibly with the goal of promoting high-quality, objective scientific research.  However, reading the information on the website and press releases, it's obvious that the organization has strong preconceived notions about diet and obesity. 
The language of the website suggests an attitude that rejects currently existing nutrition research as invalid.  I've seen this attitude before, and it's typically an effort to discredit contradictory evidence so it doesn't have to be incorporated into one's worldview.  Here are some examples of this:
If people had the correct information- based on rigorously produced scientific evidence- about which foods predisposed them to obesity and its related diseases, most would make the correct choices and lead happier and healthier lives.
Poorly controlled experiments are considered sufficient basis on which to form dietary recommendations on the belief that they are the best science can offer, not because they are inherently rigorous enough to establish reliable knowledge.
There is more than a grain of truth to this, but the reality is that we already know a lot about how to prevent obesity and type 2 diabetes, and a fair amount about how to combat existing obesity.  Much of this knowledge comes from well controlled experiments in humans and animals spanning decades of research.  The average person doesn't eat donuts and pizza, drink sweetened beverages, and sit in front of the TV for hours a day because she thinks they're going to promote a leaner, healthier life.  There are certainly gaps in our knowledge.  But the main reason we have an obesity epidemic isn't that we lack the right information, it's that most people don't apply the information we already have!  This doesn't apply to all individuals, but at a population level it does apply.
The NuSI website goes on to attribute the obesity epidemic to the US government dietary recommendations since 1977, when Americans were advised to reduce fat intake and replace it with unrefined carbohydrate (the fact that the recommendation was for unrefined carbohydrate is not mentioned).  This is inappropriate for an organization whose stated goal is to objectively support research on what causes obesity-- they should be keeping their personal opinions to themselves.  The way the website is written, it sounds like they already have their minds made up about what causes obesity, and they're simply looking to drum up confirmatory evidence. 
The press release states that "despite following current dietary recommendations- for example, reducing fat intake- Americans are getting more and more obese".  Then comes the familiar graph of macronutrient changes over the last 40 years showing a decline in the percent energy from fat, and an increase in the percent energy from carbohydrate.  Yet what escapes mention is that the only reason the percentage of fat went down is that total carbohydrate (and calorie) intake went up.  The absolute, total amount of fat intake in grams stayed the same or increased over that time period (depending on the data source-- USDA food disappearance or NHANES surveys).  Does that count as "reducing fat intake"?  Below is a graph of macronutrient intake in the US between 1970 and 2006, expressed as calories not percentages, from USDA data adjusted for loss.  You be the judge.

If we go back to 1909, a time when obesity was less common than in 2012 or even 1970, the US diet was 57 percent carbohydrate, as opposed to 49 percent today.  Total carbohydrate intake in grams was also higher than today, and most of it came from white flour (1).  Why would carbohydrate cause an obesity epidemic today when it didn't 100 years ago, and it continues not to cause obesity in numerous high-carbohydrate cultures throughout the world?
The reality is that the USDA dietary guidelines since 1977 didn't tell Americans to:
  • Increase our intake of sweetened soda by 41 percent
  • Replace fresh potatoes with french fries and potato chips
  • Increase added sugars by 16 percent
  • Increase our intake of refined instead of unrefined carbohydrate
  • Nearly double spending on fast food
  • Eat more than twice as many snacks
  • Increase total calorie intake by 20 percent
Are the USDA dietary guidelines perfect?  In my opinion, no.  Did they cause the obesity epidemic?  Absolutely not.  If everyone in this country ate strictly according to the USDA dietary guidelines, including the recommendation to favor unprocessed foods and avoid sweetened beverages, as a population we'd be leaner and healthier than we are right now. 
For these reasons among others, the materials released by NuSI do not scream "objectivity", which is troubling considering the organization's stated goals.  However, keep in mind that NuSI is a funding mechanism and will not have control over how research is conducted or reported in scientific journals.
The Bottom Line
I support NuSI, despite its flaws. It's hard to predict the long-term effects of something like this, but I think it has more potential to do good than to do harm.  I wish it well and I'm happy to help if help is requested.

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