Arya M. Sharma, MD

Regular readers of these pages will be well aware of the recent slew of evidence suggesting that not getting enough sleep is an important risk factor for weight gain (as anyone who works shifts probably knows from their own experience).

But, as always, not everyone appears to be equally affected.

A paper by Jean-Philippe Chaput and colleagues from the University of Ottawa, just published in SLEEP, suggests that sleep deprivation may especially tend to promote weight gain in people who tend to be disinhibited eaters.

Based on the examination of 276 adults aged 21 to 64 years and followed for 6 years in the Quebec Family Study, Chaput and colleagues found that individuals having both short sleep duration (loss than 6 hours a night) and high disinhibition eating behaviour (as assessed by the three factor eating questionnaire) were more likely to gain weight and increase their abdominal circumference over time.

In contrast, short-duration sleepers with a low disinhibition eating behavior trait had the same weight trajectory as those with average sleep duration.

Over the 6-year follow-up period, the incidence of overweight/obesity for short-duration sleepers with a high disinhibition eating behavior trait was 2.5 times more frequent than for short-duration sleepers with a low disinhibition eating behavior trait.

This increased risk of high disinhibition in short-duration sleepers was largely explained by higher caloric intake.

For those of us still dealing with leftovers from yesterday’s turkey, getting enough sleep may help with any ‘disinhibition’ we may experience when opening the refrigerator.

AMS
Edmonton, Alberta

Chaput JP, Després JP, Bouchard C, & Tremblay A (2011). The Association between Short Sleep Duration and Weight Gain Is Dependent on Disinhibited Eating Behavior in Adults. Sleep, 34 (10), 1291-7 PMID: 21966060

Today’s post is another excerpt from “Best Weight: A Practical Guide to Office-Based Weight Management“, recently published by the Canadian Obesity Network.

This guide is meant for health professionals dealing with obese clients and is NOT a self-management tool or weight-loss program. However, I assume that even general readers may find some of this material of interest.

CHAPTER 5: MEDICAL BARRIERS

Physical co-morbidities are common in people with obesity and need to be addressed as part of any weight-management plan. Co-morbidities associated with obesity will improve as weight is controlled, but often make it difficult for patients to undertake the effort required for lifestyle-based weight management. In some cases, these physical barriers to weight loss may be insurmountable and the focus of treatment should, from the outset, aim to prevent weight gain rather than achieve weight loss. Strategies for obesity treatment should always be adapted to the patient’s particular situation to make it easier for them to cope with required changes over the long-term.

SLEEP DISORDERS

Sleep disorders are very prevalent among obese people. Obstructive sleep apnea is the most common disorder, but disturbed sleep may also be due to primary insomnia, or insomnia secondary to medications, medical or psychiatric disorders.

Sleep deprivation is linked to obesity. The primary putative connection can be found in the neuroendocrine regulation of appetite and food intake. Neuroendocrine regulation appears to be influenced by sleep duration and sleep restriction, with sleep deprivation favouring obesity as it increases serum cortisol and decreases serum leptin levels. Another reason for the sleep disorder-obesity connection may be simply that the more time a person spends awake, the more time they have in which to eat.

Insufficient sleep causes important neurocognitive changes such as excessive daytime sleepiness, fatigue and altered mood. These may, in turn, have a significant impact on the patient’s ability to persist with healthy lifestyle changes such as increasing their level of physical activity or taking the time to cook a healthy meal.

© Copyright 2010 by Dr. Arya M. Sharma and Dr. Yoni Freedhoff. All rights reserved.

The opinions in this book are those of the authors and do not represent those of the Canadian Obesity Network.

Members of the Canadian Obesity Network can download Best Weight for free.

Best Weight is also available at Amazon and Barnes & Nobles (part of the proceeds from all sales go to support the Canadian Obesity Network)

If you have already read Best Weight, please take a few minutes to leave a review on the Amazon or Barnes & Nobles website.

Readers will recall a post earlier this week on the importance of sleep for weight management.

Researchers and clinicians, wanting to know more about the underlying biology and mechanisms on how lack of sleep, disruption of circadian rhythm (e.g. through shift work, jet lag, or having a baby), and alterations in light/dark cycles can impact ingestive behaviour and energy metabolism may wish to read a comprehensive review just published in the Annals of Medicine.

In this paper, Russel Reiter and colleagues from the University of Texas, San Antonio, summarize the potential contributions of three processes that may be contributing to humans becoming progressively more overweight: circadian or chronodisruption, sleep deficiency, and melatonin suppression.

As the authors point out:

“Circadian disruption, sleep deficiency, and melatonin suppression have at least one common causative feature, i.e. excessive light exposure including even brief periods of light at night. Indeed, interrupting the normal dark period with a short interval of bright light may be the most disruptive. Certainly, light pollution throughout the world, and especially in the economically well developed and developing nations, where obesity is also the most common, has become a major problem and is a serious concern. The use of artificial light after darkness onset in the evening and in the morning before sunrise is commonplace and impacts the physiology of the circadian system which influences both nocturnal melatonin synthesis and sleep. Moreover, being exposed to light after darkness onset due to what is referred to as trespass light or intentionally turning on a lamp is disruptive to the circadian system, which reduces melatonin levels and disturbs sleep.“

Obviously, looking at bright light sources such as a TV, a computer screen or a backlit e-Book can be even more disruptive.

Perhaps we should now all plan for candle-light dinners and then call it an early night?

AMS
Leipzig, Germany

Reiter RJ, Tan DX, Korkmaz A, & Ma S (2011). Obesity and metabolic syndrome: Association with chronodisruption, sleep deprivation, and melatonin suppression. Annals of medicine PMID: 21668294

Regular readers of these pages will be well aware of the many studies that now show a close association between less sleep and weight gain.

In fact, a now often shown slide clearly documents, how steadily decreasing hours of sleep remarkably parallels the steady increase in obesity rates over the past decades.

In addition, substantial data from animal experiments clearly documents how sleep deprivation has profound obesogenic effects on appetite and metabolism.

So does getting more sleep protect against obesity or even help with weight loss?

This question was now addressed by Jean-Phillipe Chaput (CON Bootcamper) and colleagues at the University of Ottawa in a paper just published in the International Journal of Obesity.

The researchers analysed data from a 6-year longitudinal, observational study in adults aged 18-64 years.

Short-duration sleepers (<6 h per day; n=43) at baseline were divided into two groups: (i) those who increased their sleep duration to a ‘healthy’ length of 7-8 h per day at year 6 (mean increase: 1.52 h per day; n=23); and (ii) those who maintained their short sleep duration habits (mean change: -0.11 h per day; n=20).

While both groups had similar baseline characteristics, short-duration sleepers who maintained their short sleep duration experienced a greater increase in body mass index (BMI) (difference: 1.1) and fat mass (difference: 2.4 kg) over the 6-year follow-up period than short-duration sleepers who increased their sleep duration, even after adjustment for relevant covariates.

In contrast, there was no significant difference in adiposity measures between short-duration sleepers who increased their sleep duration and a control group of individuals who reported sleeping 7-8 h per day at both baseline and year 6 (n=173).

As the authors point out, this is the first longitudinal data suggesting that increasing sleep duration in individuals with short sleep duration is associated with a reduced risk of weight gain.

Clearly, it would perhaps now be time for a controlled trial of sleep intervention in short-sleepers with weight problems.

While it is unlikely that simply getting more sleep will lead to weight loss - remember, prevention of weight gain is the first sign of success.

I wonder if my readers notice any relationship between lack of sleep and their own propensity for weight gain.

AMS
Edmonton, Alberta

Chaput JP, Després JP, Bouchard C, & Tremblay A (2011). Longer sleep duration associates with lower adiposity gain in adult short sleepers. International journal of obesity (2005) PMID: 21654631

Yesterday, the media were awash with reports on a new study out from Temple University, Phildadephia, regarding the strong association between bottle feeding beyond the age of two and the prevalence of childhood obesity at age 5 1/2.

In this paper, published in the Journal of Pediatrics, Rachel Gooze and colleagues examined data on 6,750 kids born in 2001 from the Early Childhood Longitudinal Study, Birch Cohort.

According to their analysis, about 23 per cent of kids, bottle fed after age two were obese at 5 1/2, compared to only 16 per cent of kids who were off the bottle.

Surprisingly, more than one in five kids over the age of two were still using the bottle as their primary drink container and/or were being put to bed with the bottle.

In an interview with Anne-Marie Tobin from the Canadian Press, I offered the following comments:

“Liquid calories tend not to have the same effect on satiety, or feeling full, as solid calories. In an older infant, it’s usually that the calories in the bottle are on top of what that kid might be eating, because those liquid calories have virtually no effect on satiety or hunger.”

“Thus, as discussed in the study, if a 24-month-old girl of average weight and length who is put to bed with a 250-millilitre (eight-ounce) bottle of whole milk, receives approximately 12 per cent of her daily caloric needs from the bottle, this might be fine if the child is eating 88 per cent less calories in regular meals throughout the day”

“But what happens in reality is the kid will eat 100 per cent of the calories it needs, and then you’re adding another 12 per cent at night because you’re giving her the bottle to put her to sleep.”

I also noted that:

“When kids are at this crucial stage of development, issues of satiety, appetite, hunger and a reward system are being hard-wired into a child’s brain, and they’re very hard to undo.”

“It makes a lot of good sense not to be drinking your calories in the first place once you can move to actually eating your calories.”

“Food is not a narcotic, it is not a sedative … and here, you’re using food to put someone to sleep. That’s like taking a sleeping pill. You’re using it as a narcotic. That’s not a good use of food or calories. And that’s not a good habit to get into in the first place.”

Furthermore:

“A child who is breastfeeding is in control and drinks until he’s full, whereas control is with the parent when a child is bottle-fed. Even if the child is satisfied and pushes the bottle away, a caregiver might continue insisting that it be finished.”

Importantly, however, I also noted that a longitudinal study, although revealing findings that are highly plausible, should not be taken to prove causality.

Nevertheless, given the strong biological rationale based on what we know on neurodevelopmental aspects of ingestive behaviour, I would not be surprised if similar associations are found in other birth cohorts and that future intervention studies (although hard to do) may well prove that denying kids the bottle after age two may reduce the risk of future obesity.

It should also be noted that although this study found a 33% increased risk of obesity at 5 1/2, this comes nowhere near the 300% increased risk of obesity associated with less sleep found in the Quebec Family Study.

There will never be one thing that fully explains obesity in everyone - not unlike genetic risk, each single factor can be a small piece of the puzzle - impacting some folks more than others.

The more we understand this, the better (some would say the only) chance do we have to deal with this issue.

AMS
Toronto, Ontario

Gooze RA, Anderson SE, & Whitaker RC (2011). Prolonged Bottle Use and Obesity at 5.5 Years of Age in US Children. The Journal of pediatrics PMID: 21543085