Posts Tagged ‘New England Journal of Medicine’

Breaking the Obesity Cycle

by G. John Mullen, DPT 2011 |

The United States is the most obese nation in the world. Awesome…well done, America. 30.6% of Americans are believed to be obese, 6% higher than the next country, ironically, our Americanized neighbor… Mexico (3)! It is estimated 50% of Hispanics born since 2000 will become diabetic. Mississippi currently holds the crown as the fattest state in the fattest union and has been for the past 5 years, with obesity estimated at 32.5%3. Mississippi also holds the award for fattest children at 44.4% of 10-17 year olds (3). Five states have a current adult obesity percentage over 30%3. To top it off, obesity rates have more than tripled in the past 30 years! These obesity rates are out of control and are a huge weight on the United States budget. On the other end of the spectrum, Colorado is the thinnest state in the union with an obesity rate of 18.9% and is the only state with an obesity rate under 20% (3).  The take home message: America has a weight problem.

Where is all this weight coming from?

The cause of obesity is relatively simple: weight gain occurs when caloric intake exceeds caloric expenditure. Despite the simplistic nature of obesity, weight maintenance and loss are thought of as difficult or impossible tasks. Roughly 25% of American adults report no leisure time activity and 60% report activity levels less than the value shown to reduce their risk of disease (5). No wonder we’re overweight! To add insult to injury, overweight individuals are more inclined to be inactive, with 33% of men and 41% of women reporting inactivity (5). At the same time, roughly 50% of women set a New Year’s resolution to lose weight2. We, as a society, acknowledge the problem and are committing to fixing it each January 1st but seem to fail over the course of the year.

What does it take to lose weight?

Federal guidelines suggest a minimum of 150 minutes a week of moderate-intensity exercise to obtain “substantial health benefits” (4). These health benefits are not associated with weight management, but rather with lowering rates of chronic disease. A recent publication in the Journal of American Medical Association followed 34,079 healthy US women from 1992-2007 studying their activity level and associated weight gains/losses. This study concluded that (amongst women consuming a “normal” diet) physical activity was associated with less weight gain (5 lbs) in women with a BMI lower than 25. The “activity level” was defined as 60 minutes of daily moderate-intensity activity for the duration of the study (4). However, only 45% of women in America are estimated to have a BMI of 25 or less. This study does a great job looking at activity level for weight management, but does not tell us about the volume of exercise necessary for weight loss.

Weight Loss vs. Weight Management

The Harvard study discussed above looked at women with an average age of 54.2 years with no medical complications (cardiovascular disease, cancer, etc.) (4). Women with a BMI of 25 were able to maintain their weight within 5 pounds of their weight at the beginning of the study if they exercised with moderate-intensity activity for 60 minutes a day throughout the study. Moderate-intensity exercise includes bicycling, callisthenics and fast walking (~3.0 MPH or 55-69% of maximal heart rate). However, these same protocols were not successful for weight management in females over a BMI of 25, which constitutes more than half of Americans! This research suggests that overweight or obese women need to change one of the two variables associated with weight management: decrease caloric consumption or increase caloric expenditure. The most important piece of a weight management program is consistency. As stated, many New Year’s resolutions include weight loss goals (fitness centers see an exponential membership increase during January), but the volume of people in the gym returns to normal within a month. The intent is correct but the execution falls short. There are many theories for this. We believe that lack of interest and enjoyment plays a huge role in the gym attrition rate between January and March. If someone does not like riding a stationary while bike watching CNN report another Earthquake in a third world country or another vandalism case by their neighborhood, then it is highly unlikely they will exercise consistently. If we don’t like it and we don’t have to do it, we don’t do it. It’s called human volition. The American view of exercise needs to shift dramatically from a chore to a hobby. The Harvard study used METS (metabolic equivalent) to assess activity level and determined a total of 14 MET hours per week or 3 MET hours a day was sufficient in weight management for women with a BMI of 25 or less. As stated, activities with a 3 MET or higher rating include biking, fast walking, etc. 3+ MET activities also includes various hobbies not typically viewed as exercise: canoeing/kayaking, dancing, ice/roller skating, hiking, gardening and racquetball to name a few (full list of activities with their MET ratings). If you perform these activities at a more rapid pace (really start cruising with that paddle!) these activities can reach the upper echelon of METS. The take home message: Make exercise fun. If you don’t, you’ll quit. If you do, you can potentially burn more calories than you would boring yourself to death on a stationary bike watching Larry King.

Weight loss is a tougher nut to crack and is often person-dependent. Common sense makes it sound as simple as increasing caloric expenditure, but exercising greater than one hour a day is unrealistic for many and leads to failed goals and the aforementioned NYE resolution abandonment. Often times, physical activity is not sufficient in weight loss due to the multivariable nature and complexity of the problem. Many of these issues are related to diet.

Diet is the number one contributor to weight loss. Here are a few simple tips for those trying to lose weight (be sure to stay tuned for more from our staff dietitian):

  • Do not limit yourself to strict caloric restriction diets. The math is complicated and the stress at each meal is unnerving. This approach is hard to consistently maintain leading to failed goals and disappointment. Strict diets can decrease metabolism making the body more likely to gain weight once the diet is discontinued. Instead, monitor diet and decrease consumption of high caloric foods. For example, you can eat four bananas or one McDonald’s double cheeseburger…they have the same number of calories. We guarantee that eating four bananas will be just as filling as a double cheeseburger and the four bananas cost less and have more vitamins than the McDonald’s double cheeseburger.

  • Monitor drink consumption. Energy drinks, frappuccinos, etc. contain high quantities of unfilling calories. Replace these high calorie, high cost options with….water! Simple and effective.

  • Prepare your own food and eat foods that require some work. When was the last time you ate an uncooked carrot? It takes a while to consume and requires a lot of chewing. Increasing the amount of chewing can trick the mind regarding the amount of food being consumed, decreasing hunger.

These three tips are easy to perform and are, most importantly, cost efficient. Some additional factors affecting your ability to lose weight include:

  • Sleep: Inadequate sleep impairs hormones (ghrelin and leptin) that regulate hunger and satisfaction following food consumption. One study found people who slept less than 8 hours a night had lower levels of leptin (controlling satisfication) and higher levels of ghrelin (controlling hunger) AND higher levels of body fat (1).

  • Stress: Cortisol is a hormone produced in response to stress. Cortisol release causes insulin release resulting in increased hunger. The take home message: Relax! You can use multiple stress reduction techniques including deep breathing, meditation, visual imagery, and exercise. Take your pick.

We all know that weight management is an issue in America as obesity rates continue to rise. An undeniably effective approach to weight loss is exercise. The goals is a calorie expenditure > calorie intake. Remember that exercise should be a hobby and not a chore! Find activities you enjoy and stick with them. Set realistic goals that target three areas: appearance, health and consistency. If exercise alone does not achieve your weight goals, diet, sleep and stress can also be manipulated to make your weight goals a reality.

Questions? E-mail John:


  1. Bouchez C. How Sleep Affects Your Weight. 2007.

  2. Losing Weight Is One Of The Most Popular New Year’s Resolutions. Medical News Today. 2005.

  3. F as in Fat 2009 – Trust for America’s Health. 2009.

  4. Lee I, Djoussé L, Sesso H, Wang L, Buring J. Physical activity and weight gain prevention. JAMA. Mar 2010;303(12):1173-1179.

  5. Mokdad AH, Bowman BA, Ford ES, Vinicor F, Marks JS, Kaplan JP. The continuing epidemics of obesity and diabetes in the United States. JAMA JAM Aabbr. Journal of the American Medical Association 2001;256:1 195-1200.


05 2010

Prevent Jet Lag: Who wants to be tired on vacation?

by Kelly Erickson, MD 2010 |

Sleeping on the PlaneWith record-breaking storms keeping many Americans trapped indoors this winter, it is hard to imagine that summer will ever come.  Daydreaming about your spring getaway or summer vacation to Europe may be your only respite from the cold.  But when you consider vacation, especially one that takes you multiple time zones away from home, one of the major drawbacks is coping with the even harsher reality of “jet lag”.  Whether it requires you to sleep when you arrive at your destination rather than enjoying immediate exploration or demands that you take yet another day off from work once you return home, jet lag is undeniably inconvenient.  Here we will explain the causes of jet lag and how to best prevent it from hindering your well-deserved adventures.

What is jet lag?

According to a recently published article in The New England Journal of Medicine, jet lag is a “recognized sleep disorder that results from crossing time zones too rapidly for the circadian clock to keep pace.”  It is a constellation of symptoms that can Jet Laginclude insomnia, daytime sleepiness, fatigue, poor physical performance, cognitive impairment and gastrointestinal changes.  What the scientists meant to say was that you are going to feel lousy.   Jet lag is most commonly experienced after crossing at least 5 or 6 time zones (the East Coast-West Coast trip doesn’t apply here!).  Jet lag is most commonly confused with “travel fatigue”, which is the unfortunate result of the combination of sleep deprivation, stress caused by traveling, diet changes, etc.  While travel fatigue can be easily treated with a little rest and T.L.C., jetlag is a horse of a different color.

How does this “jet lag” nonsense happen?

The body’s circadian clock is located in the suprachiasmatic nucleus (SCN) of the hypothalamus (imagine a point directly between your eyes and two inches towards the back of your head…eureka, you’ve found it!).  It communicates with the retina, allowing it to sense light and dark.  Suprachiasmatic NucleusBased upon our regularly predictable cycle of waking and sleeping, the SCN promotes alertness or sleepiness in sync with our daily routine by regulating the secretion of melatonin from the pineal gland.  The system works such that light inhibits the secretion of melatonin.  Therefore, melatonin has often been referred to as the “dark hormone”, because it is only secreted when there is no stimulation by external light (aka nighttime).  The problem with this system is that our circadian clock does not adapt quickly to changes in the cycle (i.e. flying half-way around the world in single day).  Therefore, in the same way that “motion sickness” is the result of desynchronization between visual and spatial stimuli in the setting of movement (didn’t know that, did you?), jet lag is the body’s response to the imbalance between a predicted sleep-wake cycle and a change in external light and dark stimuli.

How to Beat It:

1.  Re-sync your clock. This is accomplished with 2 strategies.

  • Timing of Light Exposure: Based on what we now know about the circadian clock, we now understand how light can be used as a powerful tool to “trick” the circadian clock and therefore advance or delay it.  Although it may seem logical to think that sleep itself resets the clock, it is actually exposure to light and dark that is most effective.  What does this mean?  Studies have shown that light exposure should be used as follows after travel. Eastward travel: Upon arrival seek exposure to bright light in the morning.  This will help delay your circadian clock.  Westward travel: Seek exposure to bright light in the evening, which will help advance your circadian clock.

  • Taking Melatonin:  Because light inhibits melatonin secretion, recommendations for Melatoninmelatonin are the opposite of those for light exposure.  When melatonin is taken in the evening, it resets the body clock to an earlier time and when taken in the morning, it causes the clock to be set to a later time.  Guidelines for melatonin use are, once again, broken down depending upon the direction of travel.  Eastward travel: Take 0.5mg-3mg at bedtime to shift your circadian clock to an earlier time and help you fall asleep.  Westward travel: Take 0.5mg during the second half of the night to shift circadian clock to later time and allow you to continue to sleep.  When traveling westward, the most common sleep disturbance is difficulty staying asleep.  Therefore, melatonin should be taken after awaking in the middle of the night in your new time zone.


2. Plan out your ZZZZZ’s. When planning a trip, you buy your airlines tickets in advance, purchase your travel books and research all of the best sites to visit.  Why not spend a few extra hours sleeping before you leave to help ease the jetlag when you arrive?  More sleep plus less jet lag sounds like a good deal to us.  In general, this means shifting the timing of your sleep 1-2 hours earlier for a few days before eastward travel and 1-2 hours later for a few days before westward travel.

3. Medication. When all else fails, manage your symptoms with some good old-fashion meds.

  • Downers (aka sleeping pills):  Studies have shown that 10mg zolpidem at bedtime helps patients get a good night’s rest after long-distance travel and helps to reduce the symptoms of jet lag.  It’s best if you give the medication a test-run before you leave to ensure that you do not have any unwanted side effects while in the safety of your home country (amnesia and confusion…not so fun in a new city where you don’t speak the language).

  • Uppers: Caffeine, while generally discouraged for those attempting to overcome jetlag, can be used in small doses early in the day to increase daytime alertness and decrease sleepiness.  Small doses for those of you who missed that part the first time.

The Take Home Message: Jet lag sucks (as the scientists so eloquently explained) but can be mitigated with some planning, preemptive measures before you leave home, and a little proactive management once you’re on the ground in your exotic location of choice (our advice: print out this article so you can remember all these tips when it’s go time).  There’s no reason to feel like poop during your valuable travel time.  Vacation, here we come.  Now get packing!

Questions?  E-mail the author: Kelly Erickson, MD 2010 |

Bora Bora, French Polynesia


1.  Sack, Robert L.  Jet Lag.  The New England Journal of Medicine 2010; 362:440-7.

2.  Herxheimer, A., Sanders, M., Mahowald, M., Sokol, H.N., Jet Lag. UpToDate, 2010.

3.  Herxheimer, A, Petrie, KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database Syst Rev 2002; :CD001520.

4.  Jamieson, AO, Zammit, GK, Rosenberg, RS, et al. Zolpidem reduces the sleep disturbance of jet lag. Sleep Med 2001; 2:423.

5.  Morris HH, 3rd, Estes, ML. Traveler’s amnesia. Transient global amnesia secondary to triazolam. JAMA 1987; 258:945.


02 2010

Decoding Diets

There are millions of diets in existence, with new fad approaches to weight loss popping up each month.  From theApple a Day ever popular South Beach Diet, a high-protein, low-carbohydrate approach, to the very entertaining Cayenne Pepper and Water diet, essentially a starvation diet, it’s hard to sort through the myriad of approaches to weight loss.  Additionally, there is little scientific evidence to support the effectiveness of any of these plans.  Why punish yourself with cayenne pepper water three times a day if it doesn’t even help you lose weight?

This month, the New England Journal of Medicine, one of the most reputable journals in medicine, published the study, Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates,” to help dieters decode the plethora of diets peppering society.  The study examined 811 overweight adults (people with a Body Mass Index between 25 and 40) who were assigned to 4 different diets.  The participants received regular, personalized diet training during the entire study encouraging diets with less saturated fat, at least 20 g of dietary fiber per day, and low cholesterol.  The four diets studied were classified by the amount of fat, protein, and carbohydrates that each diet consisted of:

1.      Low-Fat, Average Protein: 20% Fat, 15% Protein, 65% Carbohydrates

2.      Low-Fat, High Protein: 20% Fat, 25% Protein, and 55% Carbohydrates

3.      High Fat, Average Protein: 40% Fat, 15% Protein, and 45% Carbohydrates

4.      High-Fat, High Protein: 40% Fat, 25% Protein, and 35% Carbohydrates

The target number of calories consumed per person was calculated as a 750 calorie deficit per day (meaning that if your body consumes 3000 calories per diet, which we call your Basal Metabolic Rate, your target diet would consist of 2250 calories per day).  You’re saying to yourself, “How on earth am I supposed to know what my Basal Metabolic Rate (BMR) is?”  There are a series of formulas that calculate this value for you based on age, height, weight, and amount of exercise you complete each day.  Follow this link to a convenient BMR Calculator (Click on BMR & RMR Calculator…and don’t forget to adjust your caloric need based on your daily physical activity).

Big KidAfter 2 years of monitoring participants weight loss, the study concluded that “reduced-calorie diets result in clinically meaningful weight loss regardless of which macronutrients they emphasize.” Essentially, it doesn’t matter which diet you choose.  The most important factor in creating a diet is calculating the number of calories your body needs to consume, making sure that the diet you design consists of 750 calories less than your BMR per day. The study found that the majority of weight loss occurred in the first 6 months of the diet (i.e. if you haven’t lost any weight after 6 months, you aren’t on the right diet).  Additionally, all of the diets reduced risk factors for cardiovascular disease and diabetes (a definite bonus).

The Take Home Message: The amount of food you consume is just as important, if not more so, than the types of food your diet consists of.  Whichever diet you choose, be sure to calculate your individual caloric needs based on your age, height, weight, and physical activity and are eating the appropriate number of calories per day based on that number.

Diet Results


03 2009

WordPress SEO