Depression and Obesity: Which disorder begets which?

The relationship between obesity (BMI >30) and depression has been characterized as the chicken/egg dilemma. Which came first? It seems self evident that depression might lead one to seek out the solace and sensory rewards of foods. And viewing that seemingly self-evident proposal in the mirror; obesity might lead to social isolation, discrimination and other real or perceived losses all associated with social stigmata, which might lead inevitably to a depressive state. The question that might be posed is: Do those with obesity have mood disorders (specifically depression) more often than those without obesity?

Research in the past has shown that obesity is significantly associated with depression and other mood disorders. What the research hasn’t been able to show is a cause and effect relationship between obesity and depression. There are a small number of studies examining the possibility of depression leading to obesity[1]. And an equally small number of studies showing that obesity might lead to depression[2]. The research in general doesn’t really lend a direction to this dilemma.

A recent study published in the Archives of General Psychiatry sought to better define the population of obese individuals at risk for depression. Or if you look at it from the other perspective, depressed individuals that happen to be obese. The study looked at a cross section of America[3] and simply examined the association between obesity and mood disorders.

They found in their cross-section of America that from 2001 to 2003 in a random sampling of the 48 contiguous states, that 25.5% of us have a BMI greater than or equal to 30. That is, 25.5 % of us are obese or larger. Further, 18.6% of those with a BMI > 30 had a major depressive disorder at one time in their lifetime. I’ll sum up the other findings:

1. White (non-hispanics) were more often depressed if obese than non-whites
2. Depression was more common in those obese individuals with higher levels of educational attainment
3. As age increased, obesity was more often associated with depression

Cross-sectional analysis such as the study above might be more a snapshot of America than an analysis of trends, but the snapshot shows some interesting associations. In higher socioeconomic circles there might be more pressure to be normal weight and those with obesity are shunned to a greater extent than those in lower socioeconomic circles. Cultural and ethnic analyses show that in some racial groupings, depression is low and may be low due to greater acceptance of obesity by peers. And those attaining higher levels of education may feel guilt and loss of self-control (with subsequent depressive episodes) due to a contrast between the self-control and will power it takes to attain higher levels of education and the state of obesity.

Which begets which? I think after examining a sampling of the studies it appears to work both ways. In some cases, possibly those in higher social strata with higher levels of education, obesity might lead to social isolation and depression. However in some (not so clearly identified by the above research study), depression and isolation may lead to overeating and sensory rewards which can lead to obesity. I think the forces leading one disorder to the other are situation specific and not amenable to generalized identifying markers or settings.
WG

[1] Goodman, et al. A Prospective Study of the Role of Depression in the Development and Persistence of Adolescent Obesity. Pediatrics 2002; 110, 497-504
[2] Roberts EE, et al. Prospective Association between Obesity and Depression. Int J Obesity Rel Met Disorders 2003;27: 514-26
[3] Simon et al. Association Between Obesity and Psychiatric Disorders in the US Adult Population. Archives of General Psychiatry. 2006;63:824-30

Happy Feel-good Reward

In the course of an interview today I had the opportunity to observe an interesting exchange between a mother and her 2 year old daughter. Interesting, in the sense that it gave me a reason to pause and think about the roots of obesity briefly and the factors we as parents promote by encouraging overeating, and eating what we would all consider the wrong kinds of foods. It’s a surprisingly common approach to children’s behavior and in this case the child was acting fine; she was making faces at me and acting goofy, but nothing out of the ordinary for a 2 year old. The mother made the remark to her daughter, as we were discussing her 2 year old daughter’s health, that if she’s good during the interview, she would be rewarded with a trip to McDonald’s.

The mother in this case was herself obese (roughly 5’4”, 250lbs) and it struck me that the reward to the child might possibly be rewarding the parent as well. So what did I learn from that short exchange? Food is being given to children as a reward. There’s nothing fancy or scientific about it. There is nothing profound to say, other than the carrot being dangled in front of this small child is a trip to McDonalds. More than that, it’s teaching the child about a reward system which offers up fast food at the end of that sequence of promises.

Turning the universe upside down, what would happen in The Land of Nutritionally Correct Foods, if the mother offered up something simple like an apple or an orange as a reward if the child’s behavior was exemplary? More to the point, why in any circumstance are we offering food rewards to children based upon good behavior?

Garlic: Good for the Heart or Bad for the Breath?

The answer to the title appears to be: Bad for the breath. In a study published recently in the Archives of Internal Medicine, the impact of oral garlic either through supplementation or raw cloves, had no impact on Low Density Lipoprotein concentration (that cholesterol moiety we all call “Bad Cholesterol”).

In a randomized trial of raw garlic versus two varieties of garlic supplement versus placebo, four groups were followed over the span of 6 months whereby intake of said smelly phyto-therapeutic bulb was taken six of seven days and lipid levels were monitored. On the seventh day breath mints were handed out.

In a nutshell, by the end of the 6 month study, the groups showed no statistically significant differences in lipid levels and in particular in LDL-C levels. The study follows up other studies which have found no lipid lowering effect of garlic. It may do other things, like flavor stews or pasta dishes, but it wont prevent heart disease.

Food Policy

Nutrition policy might appear to be a concrete concept describing something meaningful and weighty, but it has no greater impact and no greater importance than the individual’s perception of the need to change—and more fundamental than that, the actual changes it induces. In a nutshell, the government and private health organizations can promote change all they like, but if the citizenry makes no change based upon the policy, the policy has done nothing.

Applying Benford’s Law of Controversy to nutrition policy: Passion in the generation of public nutrition policy is inversely proportional to the amount of information available. That is, we may be passionate in creating a policy, setting daily limits on certain macronutrients and food groups, but we risk the effect of scientific research updating current understanding and potentially showing our “policy” to be at best outdated and at worst flat wrong.

The public was universally confused in just this manner with the butter versus margarine debates over the past thirty years (actually the last 100 years). Many who flipped back to butter after the trans fat scare of the late 1990’s, are now filtering back to margarines with low trans fat content. However, ask the average shopper about the health risks of either and you get a rambling confused diatribe of concepts and fears brought on by the conflicts between science and public health policy.

Nutrition policy is ideally designed to inform and change behavior based upon a consensus of information derived from current and past science. The implication is that changing eating behavior rewards the individual with a more favorable health outcome. An example might be directed at children: Eat fewer calories, more fruits and vegetables and less saturated fats from animal sources, and enjoy lower rates of heart disease, obesity, type 2 diabetes and a host of other issues and problems. The policy, however, is actually directed at their parents and the public institutions where they learn. The policy is directed toward the prevention of obesity, heart disease and the other conditions mentioned, without directly targeting the susceptible audience (a roundabout bid once again for essential nutrition education in classrooms). What that implies, is the significance of nutrition policy is disease specific, asks a caretaker (parent or government) to administer the policy and offers no real roadmap to accomplishing the terms of the policy. It tells the parents and schools, in essence:

“We’ll tell you what to feed your children for the next twenty to thirty years, even though it’s less satisfying and offers a somewhat reduced taste experience. And we have no idea how to discourage them from eating all the good tasting, bad-for-you foods. After that, we’ll see if it prevents disease.”

And there are few real world examples of a policy that takes 30 years to bear fruit. In fact, no policy can be 100% sure of all outcomes and a policy that prevents a disease 30 years in the future is vulnerable to say the least.

The seatbelt law represents a wonderful example of a public policy that had legislative backing and thus moved quickly from policy to law. The change is immediate if one encounters another car head on at just forty miles-per-hour. However, food policy takes decades to see potential benefit. And what if the policy makers overlooked an intervening exposure? Intake of certain fruits and vegetables over time with low levels of pesticides may be found to promote certain cancers. What would we tell the populous in twenty years if the last assertion were found to be true? In truth, no policy can capture all possible conditions and situations. And no policy is perfect. But nutrition policy to prevent lifestyle accumulating disease is without question on a very buttery slope.

All-you-can-eat

The all-you-can-eat buffet is based upon a couple of very basic marketing principles and engages two very fundamental human characteristics. In an effort to scratch out another blog on this very topic, my wife and I visited a local buffet restaurant chain in an effort to see first hand the aforementioned principles in action. We both agreed that we would not enjoy the experience, although I swore to keep an open mind and evaluate the concept and the restaurant based strictly upon my senses and what I was about to observe.

The marketing principles at work in this particular establishment are:
1. Make the atmosphere as appealing as possible.
2. Deliver highly palatable foods in large quantities.

The human characteristics augmenting those principles are:
1. The need to be satisfied by the foods consumed with a variety of taste experiences.
2. The perception of a “good deal” or “bargain” based upon the price paid for the quantity and quality of food received.

The combination of marketing principles with human characteristics has allowed all-you-can-eat buffets to flourish. This particular restaurant is located near a shopping mall in an area with fairly high traffic. It’s a national chain and well-known locally.

We drove into the parking lot in stealth mode. I checked each license plate against a database of friends and coworkers to ensure anonymity. We both donned sunglasses and hats. Upon entry, the crowd gets funneled into a series of cash registers where you identify how many in your party (as well as the ages) and order drinks. The all-you-can-eat breakfast was $7.49 with coffee and tea as add-ons. The bill came to $18.00 and change. We were given a tray with six large plastic plates with two wraps of silverware.

After sitting down we each took one of the six plates and walked over to the food. It was divided up into a High Fat section and a High Refined Carbohydrates section. I started with some cantaloupe and grapefruit from the scant offerings of fresh fruit. My empty plate with fruit immediately drew numerous stares.

“Look, someone’s eating the fruit?”

In keeping with the theme I walked over to what was quite literally a mound of freshly cooked bacon. There was easily seven to ten pounds of bacon dripping with fat in a large pan. I was stupefied. I can’t remember the last time I saw that much bacon in one tray. My wife silently gave me a stern look and a nod such that I should back away from the bacon. To my amazement, a series of patrons recognizing the freshness of the bacon, lurched in front of me with elbows flared and piled the bacon on their plastic plates.

Not surprisingly, the atmosphere and tables were nicely adorned with ranch-style hominess. The tables were clean and the floor spotless. Contrary to my perceptions of trough rugged seats worn through by obese patrons eating in a miasma of bacon smoke, the restaurant was well ventilated and kept immaculate.

My wife took the first bite and declared, “Industrial food. I hope they don't get their wheat gluten from China."