Now a study by Jennifer Fenn and colleagues from the University of Vermont report significant weight gain with methadone treatment for opioid addiction in a paper published in the Journal of Substance Abuse Treatment.
The retrospective chart review included 96 patients enrolled in an outpatient methadone clinic for ≥ 6 months.
Overall mean BMIs increased by about 3 units (from 27.2 to 30.1), which corresponds roughly to an 18 lb or 10% increase in body weight.
Interestingly, the weight gain was predominantly seen in women, who gained about 28 lbs or 17.5% body weight compared to men, who only increased their weight by about 12 lbs or 6.4%.
As the study did not have access to food records, one can only speculate as to the causes. While better nutrition may well play a role, one could also speculate that there may be some addiction transfer from opioids to calorie-dense foods.
Whatever the cause, clinicians should probably be aware of this potential impact of methadone treatment on body weight, as prevention of excess weight gain may be easier than treating obesity once it is established.
Now a study by Benoit Chassaing and colleagues published in NATURE, suggests that dietary emulsifiers may promote weight gain and the metabolic syndrome by altering the composition of intestinal microbes.
The researchers hypothesized that emulsifiers may increase bacterial translocation across intestinal mucosa, thereby promoting local and systemic inflammation as well as affecting the composition of gut bacteria.
Their study in mice show that relatively low concentrations of two commonly used emulsifiers (carboxymethylcellulose and polysorbate-80) can induce low-grade systemic inflammation, weight gain and features of the metabolic syndrome, as well as promote intestinal inflammation in mice susceptible to inflammatory bowel disease.
Importantly, they used germ-free mice and faecal transplants to show that these changes can be induced simply by transferring the gut microbes from emulsifier-treated animals to controls.
As the authors note,
“These results support the emerging concept that perturbed host-microbiota interactions resulting in low-grade inflammation can promote adiposity and its associated metabolic effects. Moreover, they suggest that the broad use of emulsifying agents might be contributing to an increased societal incidence of obesity/metabolic syndrome and other chronic inflammatory diseases.”
While these findings (if replicated in humans) certainly point to the industrial use of food emulsifiers as a potential cause of the global increase in obesity and inflammatory bowel disease, given that these compounds are present in virtually all processed foods, they may well be difficult to avoid.
Guess it’s back to home cooking with raw ingredients.
Visiting the local farmers’ market is one of our family’s dearest weekend rituals. It is indeed hard to not come away feeling that you’ve done good for yourself (thanks to the fresh produce) and for the local farmer community.
But this illusion is challenged by Sean Lucan and colleagues from New York in a paper published in Appetite.
The researchers assessed all farmers’ markets in Bronx County (n=26), NY, in terms of specific foods offered, and compareed their accessibility as well as produce variety, quality, and price to that of nearby stores (within a half-mile walking distance, n=44).
Not surprisingly, farmers’ markets were substantially less accessible (open fewer months, days and hours), carried far fewer items and were far more expensive than nearby stores that also sold fresh produce.
The researchers also found that about one third of what farmers’ markets sold was not fresh at all, but rather consisted of refined or processed foods including jams, pies, cakes, cookies, donuts, and juice drinks).
Thus, overall, the researchers conclude that,
“Farmers’ Markets offer many items not optimal for good nutrition and health, and carry less-varied, less-common fresh produce in neighborhoods that already have access to stores with cheaper prices and overwhelmingly more hours of operation.’
So, while there may well be good reasons to celebrate your local farmers’ market, their contribution to improving population health through healthy nutrition, is probably not one them.
They are indeed little more than “feel-good boutiques” for a small minority of the urban population, who values and is willing to pay dearly for the experience.
No surprise there I guess.
A study by Ryan Newton and colleagues in mBio, the open access journal of the American Society for Microbiology, found that the bacterial composition of city sewage can almost precisely predict obesity rates in that city.
The researchers studied the microbial community of sewage from 71 US cities from 31 states using high-througput 165 rRNA gene sequencing technology.
Although on average only 15% of bacterial sequences in each sample represented bacteria known to occur in human stool, they were able to capture most (97%) of human fecal oligotypes.
Based on the distribution of three primary oligotypes representing different proportions of Bacteroidaceae, Prevotellaceae, or Lachnospiraceae/Ruminococcaceae, the researchers were able to predict whether samples came for cities with high or low prevalence of obesity with 81-89% accuracy.
No such relationship was found with non-fecal oligotypes, suggesting that this relationship was indeed due to the representation of human fecal bacteria in the sewage samples.
Obviously, it is very possible that the sewage bacterial composition reflects “lifestyles” associated with obesity rather than actual body weights, but the very fact that it was possible to identify important predictive differences in bacterial patterns between cities with varying obesity rates, together with the increasing recognition that gut bacteria may well play a role in obesity (and other metabolic diseases), is fascinating enough.
Should these findings be reproducible across other populations, I can only wonder whether sewage sampling may one day serve as a simple way to study changes in nutrition and obesity rates in whole populations.
Indeed, I can picture future public health scientists poring over sewage data to check if their public health policies to reduce obesity are in fact working.
In last week’s 2015 Lancet series on obesity, the majority of papers focus on policy interventions to address obesity. It suggests that a reframing of the obesity discussion, that avoids dichotomies (like nature vs. nurture debates) may provide a path forward – both in prevention and management.
The policy framework presented by Christina Roberto and colleagues in The Lancet, is based on the NOURISHING framework, proposed by the World Cancer Research Fund International to categorise and describe these actions.
Together, the actions in this framework address the food environment (e.g. food availability, taxation, restrictions on advertising, etc.), food systems (e.g. incentives and subsidies for production of healthier foods) and individual behaviour change (e.g through education and counselling).
This “food-centric” view of obesity is complemented by recognising that physical activity, much of which is dictated by the built environment and captivity of the population in largely sedentary jobs, also has a role to play.
On a positive note, the Christina and colleagues suggest that there may be reasons for careful optimism – apparently 89% of governments now report having units dedicated to the reduction of non-communicable diseases (including obesity), although the size and capacity of many of these units is unknown.
On the other hand, despite an increasing number of such efforts over the past decades, no country has yet reversed its epidemice (albeit there is a flattening of obesity growth rates in the lower BMI ranges in some developed countries – with continuing rise in more severe obesity).
Despite the potential role of government policies in reducing non-communicable diseases (including obesity) by “nudging” populations towards healthier diets and more physical activity, the authors also note that,
“…the reality is that many policy efforts have little support from voters and intended programme participants, and although the passage of policies is crucial, there is also a need to mobilise policy action from the bottom up.”
Indeed, there is growing list of examples, where government policies to promote healthy eating have had to be reversed due to lack of acceptance by the public or were simply circumvented by industry and consumers.
Nevertheless, there is no doubt that policies in some form or fashion may well be required to improve population health – just how intrusive, costly and effective such measures will prove to be remains to be seen.
All of this may change little for people who already have the problem. As the article explains,
“There are also important biological barriers to losing excess weight, once gained. Changes in brain chemistry, metabolism, and hunger and satiety hormones, which occur during attempts to lose weight, make it difficult to definitively lose weight. This can prompt a vicious cycle of failed dieting attempts, perpetuated by strong biological resistance to rapid weight loss, the regaining of weight, and feelings of personal failure at the inability to sustain a weight-loss goal. This sense of failure makes people more susceptible to promises of quick results and minimally regulated claims of weight loss products.”
Not discussed in the article is the emerging science that there may well be other important drivers of obesity active at a population level that go well beyond the food or activity environment – examples would include liberal use of antibiotics and disinfectants (especially in agriculture), decreased sleep (potentially addressable through later school start times and mandatory afternoon naps in childcare settings), increasing maternal age at pregnancy (addressable by better access to childcare), time pressures (e.g. policies to address time-killing commutes), etc.
Perhaps what is really needed is a reframing of obesity as a problem where healthy eating and physical activity are seen as only two of many potential areas where policies could be implemented to reduce non-communicable diseases (including obesity).
Some of these areas may well find much greater support among politicians and consumers.