Friday, August 19, 2011

A Different Approach to Obesity Counseling

Disclaimer: If improperly cited references gets your skirt in a twist then hit the back button now.  This is a review of an article I read in JADA and I have no intention of citing the 98 references from the article.  These concepts are not mine, I'm simply providing an opinion on them.  I don't know how much more clear I can make it. 

Ironic as it may be, I was recently reading an article on obesity counseling while pedaling away on the ol' recumbent bike, all in an effort to...you guessed it...drop some weight.  The name of the article was Time to Abandon the Notion of Personal Choice in Dietary Counseling for Obesity and it was published in the August, 2011 Journal of the American Dietetic Association.  Now I admit, when I read the title I had to fight the urge to let out a "what the..!" and throw the rag across the room but I had another 30 min of biking to nowhere so I thought I'd give it a rip.

The premise of the article is that the bulk of the current dietary counseling for obesity is based on personal choice or more specifically, making good personal choices.  This means that when things don't go as planned and the weight isn't coming off, the client is "stigmatized" as having low willpower.  Again, I was bristling with rebuttals and ready to toss this piece but my cardio theater options were limited and Swamp People didn't have enough RJ and Jay Paul to keep my interest so I really didn't have anything else to keep me occupied.  Let me be clear, I DO think obese patients have low willpower hence the reason I show them ways to lower their caloric intake as painlessly as possible or in dietitianese "make small changes that lead to healthy lifestyle habits". Low willpower isn't by any stretch the only etiology (poverty, mental health issues, etc..) for their obesity but it plays a huge role.

Do they really have a choice?

"The term personal choice implies that human behavior derives from conscious, volitional decisions, and connotes that human beings have free will to decide between alternative courses of action-independent of biological and environmental forces". As Riggs and Murtaugh would say "that's pretty thin" but I'm willing to leave all the counter-arguments on the gym floor (eg  plug in the morally corrupt activity of your choice and get to justifying it with the wiring and environment card) for the sake of finding a more effective counseling strategy. I was also swayed by this statement, "studies that future actions can be predicted by brain activation patterns up to 10 seconds before individuals become aware of having made a decision"supposed link. I went to the link they provided for this study and it doesn't work but after some Google-Fu I found their reference and I didn't find anything worthwhile or more meaty than that little teaser but the concept got me to put on my listening cap and I settled into the article. The link I posted works but I didn't think it provided much info.

Wasn't this a Tom Cruise movie?
The big questions around the aforementioned prediction concept would be:
1. How accurately are they predicting it? If it's not 100% it means they still have a choice and thus we really are talking about a lack of willpower.

2. What type of activities are they predicting? In otherwords, what type of sensitivity are we talking about?  I can predict if I tell my daughter not to eat any more Goldfish crackers and I leave a bowl in front of her and walk out of the room that she will eat them.  Does this mean she didn't have a choice in the matter because I could predict it? Now if they're predicting that Joe Smith will choose the chocolate wingtips over the rust cap toes 10/10 times, 10 sec before he does, then I'm intrigued.

Let's try to avoid any false dichotomies though and say their personal choice is severely compromised. So as we head into the rest of the article, we'll operate on the assumption that they don't have full control over their dietary choices.

Food Reward

"Obesity has been viewed almost exclusively as a disorder of energy homeostatis in which overeating results from insufficient satiety signaling or amplified hunger signaling. However, research conducted over the past decade has demonstrated that the sensory experience of palatable food can easily override homeostatic controls of energy balance, leading to overeating in the absence of true physiological hunger".  Ya don't say!  Captain Obvious, does this mean that I missed my chance to have NIH fund my trips to the Chinese Super Buffet so they could determine if I would eat past satiety?  Team Obvious goes on to further point out that the increased sugar, salt, and fat in our dietary habits has contributed to the palatability and thus overconsumption issues (Is Swamp People back on yet?). Finally though it gets into something interesting.  There are two factors at work in Food Reward.  The first is the pleasure you get from consuming the palatable food and the second is the motivational drive to have to get this palatable food and consume it.  Interestingly enough, obese individuals do not report any more pleasure than nonobese individuals upon consuming it.  This means that the motivational factor is likely more relevant although the article doesn't explicitely state that it is.

Bring on the Neurobiology!
According to the article, the mesolimbic system aka the reward circuit is what regulates food reward.  Of note, it also determines motivation to engage in sex, gambling, and other no-nos.  The article goes on to further explain that the food pleasure portion is tied to "opioid neurotransmission in several small hotspots in the nucleus accumbens and other regions" and the motivation to seek out this palatable food is policed by "dopamine pathways from the ventral tegmental area to the nucleus accumbens". 

Why is any of this relevant? Well, it turns out that blunted mesolimbic system neurotransmission and blunted dopamine signaling (using surrogate markers) are indeed associated with higher adiposity! Association is not causation but the theory goes that those with compromised mesolimbic systems or "mesolimbic resistance"(my term, not the article's) need more palatable food to satisfy this circuit.  The article states that "deficient neural reward processing appears to equate with greater reward sensitivity at the level of behavior"; which doesn't make a drop of sense to me but ok.  In my opinion, if the person's reward sensitivity is elevated that should mean that a little palatable food will satisfy the circuit or if the circuit is deficient then it will take a lot of palatable food to complete it.  The authors go on to say that "greater sensitivity to reward is linked to stronger food cravings, preferences for sweet and fatty foods, greater ad libitum food intake in laboratory studies, and higher body weight among adults and children". I think they are contradicting themselves here a bit. For example, earlier they stated that "obese individuals do not experience greater pleasure from palatable food than normal weight individuals".  Now they're saying that the blunted mesolimbic system in individuals with higher adiposity creates a more sensitive reward circuit (eg, a jelly donut gets them twice as excited as someone without mesolimbic resistance) resulting in stronger food cravings, especially for sweet and fatty foods?  I'll take off my wordsmithing apron though and concede that if obese individuals do indeed experience some sort of mesolimbic resistance then it is indeed more than a lack of willpower.

Inhibitory Control

So the next question is; if we have skewed food reward systems r/t mesolimbic resistance, can we suppress our urges for palatable food in the absence of physiological hunger?  The short answer is a resounding "yes!" but how often we are successful is what makes our breaks our BMI. Inhibitory control is a more scientific term for willpower and it can actually be quantified.  Just so we're on the same page; IC is the counterweight to food reward.  For example, if you have the mesolimbic resistance and your reward circuit is out of whack, the IC is what allows you to override it and still make healthy choices.  So, if you have mesolimbic resistance it will indeed take more IC than normal. According to the article, the prefrontal cortex is powerhouse for inhibitory control. Neuroimaging studies done on dieters who were given a choice between 50 pairs of healthy or tasty foods have shown that those that consistently chose healthy had greater PFC activation!  There have also been studies showing that greater PFC activation following food consumption is associated with lower adiposity and food cravings!  The not-so-exciting news is that some studies also show that stress can lower PFC activity and drop IC. To summarize, you're obese, you have mesolimbic resistance, so your reward circuit is skewed but your IC is hanging on for everything it's worth and then "boom" your tire blows out and is making you late for the in-service to your biggest account.  That my friend was the final nail in the coffin for your IC and when you finally arrive you're now able to completely justify pigging out on the Panera with your customers!

Time Discounting

This is sure to be the most explosive section of my post.  I have no doubt I will be accused of being insensitive, out-of-touch, judgemental, and probably even Republican but my skin has never been thin. Time discounting is the concept that we tend to make choices that provide pleasure in the short-term but are not in our best long-term interest. Hopefully these abilities increase/improve as we age, especially past 18 y/o but there's clearly a disparity in all aspects of life quality for those that don't progress vs. those that do. The article illustrates this phenomenon by predicting that many of us would take $200 today instead of $300 in a year. Granted, generally money is worth more today than it is tomorrow but you'd be hard pressed to get a 51% ROI in a year, in today's market. I won't flesh out the examples but could time discounting explain the number of drug dealers in low income communities, the alarming number of unwed, teen pregnancies, or the generational welfare?  Does time discounting increase risk for poverty? Could this be another possible reason why poverty and obesity are associated? Does this time discounting/poor decision making carry over to food intake as well? I could write a detailed post on any of the above examples and explain how time discounting is the real culprit but I won't; I'll keep this limited to nutriton.
I'll step off the soapbox now and get back to the neurobiology except there isn't a whole lot in this part.  Basically Team Obvious states that those who tend to time discount a lot (take the $200 today instead of the $300 at the end of the year) are going to have a hard time losing weight since it doesn't come off quickly, Jillian Michaels be damned.

Let's tie this all together!

1. You have mesolimbic resistance so you have a blunted reward circuit.  The article states this increases your reward sensitivity; meaning you get much stronger food cravings, especially for fatty and sweet foods.  I think this is hogwash or at least poorly written and that the garbled mesolimbic transmissions mean you need a greater amount of highly palatable foods to complete the circuit and thus have diminished reward sensitivity.  The greater quantity is quantified as "stronger cravings". Either way, you have reward circuit that is hard to complete.  As the article states, this fried reward circuit is associated with greater adiposity.

2. The second fork of mesolimbic resistance would be decreased dopamine signaling and that is clinically significant because dopamine is what shuts down your motivation to seek out this highly palatable food.  The article states that obese individuals don't report a greater reward for highly palatable food but they do report a much greater motivation to go find it. Not surprisingly, markers that predict poor dopamine signaling are correlated with greater adiposity.

Applications: The article states that you would need to limit the food reward by doing things like shopping with a grocery list, planning restaurant menu selections in advance, etc..  To quote my boys from Lethal Weapon, "that's pretty thin".  Number one, just because I don't put klondike bars on my grocery list doesn't mean I that I no longer find them rewarding and the elephant in the room is...wait for it...I still have to have the willpower to not put them on my list/not buy them. It also gives an example of removing palatable food cues from home and work environments but again, you have to have the willpower to do that.

Food Outreach Integration:  The majority of our clients at Food Outreach (http://www.foodoutreach.org/) are struggling with food insecurity which means they heavily rely on Food Outreach for their food.  In other words, we have a captive audience; so if we control what goes on the menu and they get most of their meals from our menu, we have a good chance to "limit the impact of reward on food choice".  Myself and the Chef(s) work together on our menu to ensure that our frozen meals are on average <100mg of cholesterol and get <10% of their cals from saturated fat. We aren't trying to be Snackwells so this has an indirect effect on our meals' caloric content as well. The clients really can't go wrong with anything they choose on our menu, assuming they aren't eating 2 or 3 meals vs. 1 in a setting.  We have built-in portion control since our frozen meals come in single serve containers.   It will be a challenge to search for ways to limit the palatable foods (for our obese clients) but at the same time keep our menu appealing for our clients that are experiencing involuntary weight loss.

3. Inhibitory Control is the angel on your shoulder telling you to "hold off" when your mesolimbic resistance has your reward circuit in overdrive.  IC is a hardworker that's chugging away at absolute capacity so when IC has to contend with anything other than policing the reward circuit (eg stress) it loses its grip on the reward circuitry and all hell breaks loose. 

Applications: Supporting your IC system is a two-pronged process.  One; don't put it in bad situations. For example, don't head to the Chinese Super Buffet and dare IC to keep you at one plate.  Oh wait...are we talking about willpower again? I have to have the willpower not to go to the Chinese Buffet.  I know, I know, I'm such an ass.  The second step in IC support is creating an environment that fosters it.  This would be lowering your stressors and/or anything that's going to get IC off task and give the mesolimbic system the chance to get buckwild.  For example, if you meet your friend once a week for dinner and it's a rat race to get to the restaurant by 6 and you feel like you always come in out of breath and barely on time; move the time back to 7pm or maybe just a different day.  Evaluate yourself and see what gets you stressed and more importantly, identify which stressors that you can actually change (eg flexible scheduling at work?).

Food Outreach Integration: The biggest thing we do at Food Outreach to support IC is to NOT place bad choices on our menu.  If we were to start an obesity support group, I would have at least one class dedicated to showing the clients how to assess their environments for pitfalls or traps that would compromise their IC.  I would likely design some type of inspection list and they would need to use said sheet as a guide to assess their environments.  Now ideally, I could go home, to work, etc.. with them and personally help them identify IC black holes but that's not feasible on a number of fronts. This is an area I'm excited about though and an IC inspection list is only the beginning.  I have a few more ideas brewing..

4. Time Discounting: TD simply put, is a tendency to make choices that give us short-term pleasure even when it is not a good long-term strategy (eg eating a whole box of chocolates while our favorite show is on TV).  Relative to obesity, this is a nightmare because food gives us immediate pleasure and depriving ourselves of food in an attempt to lose weight is a hard sell because the weight loss is something that occurs in the long-term.

Applications:  The article states that setting short-term goals, maybe even daily energy goals, are ideal for those with time discounting issues. In other words, you're taking advantage of the knowledge that they will likely make the choice that benefits them most in the short-term.  The authors also recommend  the patients prepare healthy foods ahead of time to they have easy access to them.  This is another manuever to use their predictable behavior to their advantage.  To clarify: if they have a convenient supply of healthy food right in front of their nose or they have to drive to McDonalds, which do you think someone with time discounting issues will choose?  I thought this was the weakest section in the article as far as neurobiology but this section has the most realistic and effective applications.  I would be remiss though if I didn't mention that they have to have the willpower to prepare/procure convenient, healthy foods and not put the calorically dense, highly palatable foods in their home/in competition with them.

Food Outreach Integration:   I've already discussed our frozen meals program but this is the perfect solution to providing them with an accessible, convenient source of healthy foods.  All they have to do is reheat them and they're ready to go! An opportunity for us might be a weekly support group, held on Mondays at 1pm.  We currently provide a Monday lunch to our clients.  The idea behind our Monday lunch program is to create a restaurant-like environment for our clients so that at least once a week, they feel like they can still go out and get something to eat.  Due to the cost of their treatments and medications, many of them never get to go out to eat anymore, unless you want to count dollar menu.  More importantly, since we allow them to bring a guest, it gives them the opportunity to take their careperson out for a nice meal. Where I'm going with this is simple; we already have a ton of foot traffic every Monday, so this would be the prime spot to host a support group.  The advantage to a weekly support group, relative to time discounting, is it allows us to set weekly/short-term goals and would give them the pleasure of meeting those goals in front of their peers on a weekly basis. For example, if I know I'm going to get a bunch "attaboys" on Monday, that might be enough to override my desire to blow into that bag of chips on Sunday while I watch the game.

In conclusion, although I still think a lack of willpower plays a huge role in obesity (it drives the strategies for combating mesolimbic resistance, you must have it for IC support, it essentially is IC, and much of time discounting can be explained by a lack of willpower) I can appreciate how someone's willpower might be compromised from a neurobiological standpoint. One thing is certain, we are losing the war on obesity and losing it badly.  I'm willing to try some new things and hopefully others are too! 

Thanks for reading!

Josh

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