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Study Indicates That Calories, Not Protein, Lead to Increase in Body Fat

Study Indicates That Calories, Not Protein, Lead to Increase in Body Fat

A study appearing in the the January 4, 2012 issue of JAMA indicates that when people increase the amount of food they eat, where the calories come from may significantly impact whether or not people gain fat when they gain weight.

Following 25 participants on tightly controlled diets, researchers at Pennington Biomedical Research Center in Louisiana found that when calories from protein were increased, while participants gained weight, they mostly gained lean body mass (muscle) and they ncreased thier resting energy expenditure. Those on a lower protein diet, gained body fat and lost muscle.

While controlling calories is obviously an important part of weight management, studies such as this lend insight to how the source of calories impacts critical factors like resting energy use and body composition - both of which have bearing on overall health.

Reference: JAMA. 2012;307[1]:47-55.

Health Benefits of Harder, Shorter Exercise

Health Benefits of Harder, Shorter Exercise

Exercise has long been show to benefit those with Type-2 Diabetes.  However, the American Diabetes Association current recommends 150 minutes per week of moderate to intense exercise. At just over 20 minutes per day, every day of the year, this recommendation is prohibitive for many.

A study published in the December 2011 issue of the Journal of Applied Physiology has supplied some new data suggesting that there may be other alternatives. Researchers at McMaster University assessed the benefits of of using 30 minutes per week of high-intensity exercise.  They found significant benefits and improvements in key areas of diabetic health.

While the study was very small, and is really just a proof of concept, it is an indication that those with diabetes may be able to get substantial benefits from exercise without lengthy time commitments.


Reference:

Little JP, Gillen JB, Percival M, Safdar A, Tarnopolsky MA, Punthakee Z, Jung ME, Gibala MJ. Low-volume high-intensity interval training reduces hyperglycemia and increases muscle mitochondrial capacity in patients with type 2 diabetes. J Appl Physiol.  2011 Aug 25. (epub, ahead of print)

Hit the Trail

Want to exercise outside but don't know where to start?

Staying physically active is an important part of good health and maintaining your weight.  Some people love the gym, for others a great fitness DVD gets them going, but the outdoors also offers up many options for exercising while enjoying the natural environment.

If you are drawn to exercising outside, but often have thoughts like "it's going to take too long", "what if the trail is too hard for me" or simply "where do I go" then we have found a great app to help you on your way.

The AllTrails app (from AllTrails, inc) give you access to over 40,000 trail guides for everything from walking/hiking to snowshoeing.  By accessing the GPS on your phone it lets you easily browse trails in your area by distance, length (shortest), and most popular.  A simple to use map device will even give you directions from where you are.  Once you choose a trail, you can access the trail map, read reviews by others who have been there, and more.

Because the app also gives you time estimates for completing an activity, you can also plan your outdoor time in a way that you know will work in your schedule.

This app is available both in the iTunes App Store and the Android Marketplace.  It's free - so you don't lose anything by trying it out - but you may just discover something wonderful!

Happy trails!

http://alltrails.com/

"Eat Less and Exercise More" -- It's Not That Simple

The study question: What effects do diet and lifestyle changes have on long-term weight gain? Most weight gain happens slowly over time, at the rate of roughly 1 pound a year, and few studies have previously examined what factors can affect weight gain over the long haul in healthy individuals.

This study investigated the relationship of several diet and lifestyle changes such as beverage choices and amount of sleep in nonobese men and women living in the United States. The study combined data from three different, long-term cohort studies—the Nurses' Health Study I and II, and the Health Professionals Follow-up Study—conducted from 1986 to 2006, with more than 280,000 participants. After people with chronic health problems were excluded, data from 120,877 participants were analyzed. Once participants reached age 65, they were excluded from further analysis to avoid confounding due to the loss of lean muscle mass that commonly occurs with age.

Changes in diet and lifestyle factors were measured at four-year intervals. Adjustments were made to take age, baseline body mass and lifestyle factors including physical activity, television watching, alcohol use, sleep duration, and cigarette smoking in account. Dietary factors examined included the amounts of fruits, vegetables, whole and refined grains, potatoes, nuts, dairy products, sweets and desserts, meats, fried foods, alcohol drinks, and trans fat. Several categories were broken down further: boiled and mashed potatoes, french fries, and potato chips; whole-fat and low-fat dairy products; processed and unprocessed meats; sugar-sweetened beverages, diet sodas, and 100% fruit juices; and different types of alcoholic drinks.The relationships between dietary choices and lifestyle factors were analyzed both separately and together.

The results: Small changes in individual behaviors make a big difference in long term weight. The average difference between those with the largest amount of weight gain over the study period and those with the smallest gain or actual weight loss was only 3.1 servings of vegetables per day and 25.3 metabolic equivalents of physical activity per week. Metabolic equivalents (METs) are a practical way to express the intensity of energy expended during various physical activities in a way that is comparable among different levels of physical activities performed by people of different weights. For example, brisk walking at 3 miles per hour, a moderate intensity activity, is roughly equal to 9-10 METs.

While eating more or less of any one food would change the number of calories consumed, the magnitude of weight gain was associated with specific foods and beverages. These show a strong positive association with increased weight gain. Per serving per day, potato chips resulted in a 1.69 pound gain and french fries resulted in 3.35 pounds gained. Refined grains (.39 lb) increased weight gain almost as much as sweets and desserts (.41 lb) per daily serving. Sugared sweetened beverages (1 lb), processed meats (.93 lb) and unprocessed red meats (.95 lb) all showed a similar pattern. The relationship between alcohol consumption and weight gain was not clear and requires more investigation. However, liquid carbohydrates, including alcohol, were associated with increased weight gain.

Less weight gain was robustly associated with increased consumption of other categories of foods. Per serving per day, vegetables resulted in -.22 lb, whole grains in -37 lb, fruits in -.49 lb, and nuts in -.57 lb. Dairy foods overall appear to be neutral. A surprising result was that a daily serving of yogurt was associated with -.82 lb. The authors speculate that the probiotic bacteria in yogurt may alter gut bacteria in such a way that influences weight. Increased consumption of these foods likely means less consumption of those foods associated with increased weight gain.

Physical activities such as sleep and television watching are also associated with long term weight. Weight gain was lowest among those who slept 6-8 hours a night, and was higher for those sleeping less than 6 or more than 8 hours a night. More hours of television watching appears to influence weight gain, and this may due to the opportunity for increased snacking and reduced physical activity. Smoking appears to result in a small initial weight gain, but little weight change afterwards, and the health benefits of smoking cessation far outweigh the associated risks of continuing to smoke as a means of weight management.

Is this study relevant to me? Yes. Anyone interested in maintaining a healthy weight as they age can benefit from the information contained in this study. Eating more nuts, fruits, vegetables, and yogurt appear to reduce weight gain over time, while consuming starches such as potatoes and processed foods high in fat and sugar can increase weight gain. A habitual imbalance of 50-100 calories a day may be enough to result in the gradual weight gain observed in most people.

Limitations of the study: Although this is one of the largest and most comprehensive studies to date on this issue, the study does have some limitations. Portion sizes and lifestyle behaviors were estimated, and could have resulted in some degree of error. The authors note that the true relationship with weight change is likely to be an underestimate. Participants in the study were largely white, educated adults in the United States, which may limit the generalizability of its findings to other populations.

Find this study in PubMed:
Changes in diet and lifestyle and long-term weight gain in women and men.
Mozaffarian D, Hao T, Rimm EB, Willett WC, Hu FB.
N Engl J Med. 2011 Jun 23;364(25):2392-404.

Another Reason to Avoid the Late-Night Drive Thru

The study question: Is going to sleep later in the evening associated with other factors that promote weight gain, in and of itself?

This article examined the association between the timing of sleep, that is, what time people go to bed, and whether timing alone was linked to behaviors such as eating more fast food and fewer fruits and vegetables, a higher caloric intake, and having a higher BMI (body mass index), independent of how many hours people slept.

The study sample of 27 men and 25 women was drawn from the Chicago area using flyers and online advertisements. These participants were asked to wear a wrist actigraph, a small device worn on the wrist that records movement during sleep, for 7 days. Data collected from the actigraph was used to determine sleep and wake times, and the total duration of sleep. Participants used food logs to record every food or drink they consumed daily, along with the time, location, description, and quantity of each meal or snack. Fast food was defined as anything that can be purchased from a drive-through. The calorie content of all food and drink consumed was calculated using publically available nutrition information found at www.sparkpeople.com, in conjunction with restaurant and manufacturer websites.

The results: Participants were classified as having normal or late sleep times, and these two groups were compared to each other. Those with normal sleep times had the midpoint of their sleep earlier than 5:30am and those with late sleep time had the midpoint after 5:30 am.

Compared to the normal sleep timers, late sleep timers reported fewer calories consumed at breakfast and more calories at dinner, more calories consumed after 8pm, more fast food meals consumed, more sodas, and fewer fruits and vegetables. Late sleep timers also had shorter sleep duration (5 ½ hours versus 6 ½ hours) and a higher BMI (an average of 26.0, SD = 6.9), compared to normal sleep timers (an average of 23.7, SD = 3.2). Over the 7 days of the study, later sleep timers consumed an average of 248 calories a day more than the normal sleep timers. While this difference was not statistically significant, most of these calories were consumed at dinner and after 8pm, a behavior that was associated with having a higher BMI.

Is this study relevant to me? Yes, if you are trying to lose weight. The results of this study are consistent with previous research about  weight loss, the timing of meals, and sleep. Eating after 8pm and going to sleep later in the evening may increase the risk of obesity.

Limitations of the study: The study used a convenience sample and the sample size is relatively small. The study relied on self-reported information by the participants about their dietary behavior and weight. The researchers did not measure objective metabolic and hormonal markers, so it does not address biological mechanisms that might help to explain the relationship between sleep timing or sleep duration to appetite and weight regulation. Showing an association between a behavior and an outcome alone, in and of itself, suggests but does not conclusively demonstrate a cause and effect relationship between the two.

Find this study in PubMed:
Baron KG, Reid KJ, Kern AS, Zee PC.
Role of Sleep Timing in Caloric Intake and BMI.
Obesity 2011 Apr 28.

Better Sleep, Less Stress, Lower Weight?

A new study conducted at Kaiser Permanente in Portland, Oregon looked at the impact of lifestyle factors - sleep, stress, television watching, computer use and depression - on success with a weight loss program.

For approximately 500 patients trying to lose 10 pounds, getting adequate sleep (6 to 8 hours per night) and reducing stress, was associates with a much greater degree of success in achieving their goal.  (Patients who lost 10 pounds in 6 months were admitted to the second phase of the study which will look at acupuncture and acupressure as a means of maintaining weight loss.) Individuals with the best sleep and lowest stress were twice as likely as those with poor sleep (under 6 hours) and high stress to move into phase 2 of the trial. 

While the authors caution that this data may not apply to all individuals trying to lose weight, the question of how lifestyle may impact weight loss success is one that is important.  Better sleep and lower stress have many health benefits, and unlike other kinds of interventions, do not come with unwanted side effects. 

Reference:
C R Elder, C M Gullion, K L Funk, L L DeBar, N M Lindberg, V J Stevens
Impact of sleep, screen time, depression and stress on weight change in the intensive weight loss phase of the LIFE study
International Journal of Obesity (29 March 2011) doi:10.1038/ijo.2011.60

Dieting Puts Vitamins and Minerals at Risk

The results of the "A to Z" study from Stanford University, confirm that most popular weight loss diets put vitamins and minerals at risk.  This trial look at people in four diet groups:

  1. Atkins Diet (73 patients) - high protein, low carb
  2. Zone Diet (73 patients) - low glycemic
  3. LEARN - a low calorie diet
  4. Ornish Plan - a vegetarian, very low fat diet
Researchers found that at 8 weeks, all dieters were wating about the same amount of calories, and each diet had unique nutrient deficiencies as follows:
  1. Atkins - thiamine, folic acid, vitamin C, iron, and magnesium
  2. LEARN - vitamin E, thiamine, and magnesium
  3. Ornish - E and B-12 and zinc
By contrast, those on the Zone plan had a decrease in risk for deficiency of A, E, K, and C.

Reference
http://www.ajcn.org/cgi/content/abstract/ajcn.2010.29468v1
Am J Clin Nutr 2010 Jun 23. [Epub ahead of print]

Omega 3 For Bones?

While there are many nutrients - calcium, vitamin D, vitamin K - that we know are important for bone health, there are still things that we are learning about the impact of other nutrients.  A new study indicates that fish oils like DHA may also be important for healthy bone.

The study, conducted in rats, found that animals supplemented with DHA had healthier bone marrow and increased bone density.
It is not known if these findings would extend to humans, although a recent study commissioned by NASA found that astronauts supplemented with the Omega-3 EPA had less bone loss in space compared to unsupplemented astronauts.

References:
Yong Li, Mark F. Seifert, Sun-Young Lim, Norman Salem and Bruce A. Watkins Bone mineral content is positively correlated to n-3 fatty acids in the femur of growing rats. British Journal of Nutrition, Published online by Cambridge University Press 27 Apr 2010 doi:10.1017/S0007114510001133

Journal of Bone and Mineral Research
Published online ahead of print, doi: 10.1359/JBMR091041
"Capacity of Omega-3 Fatty Acids or Eicosapentaenoic Acid to Counteract Weightlessness-Induced Bone Loss by Inhibiting NF-κB Activation: From Cells to Bed Rest to Astronauts"
Authors: S.R. Zwart, D. Pierson, S. Mehta, S. Gonda, S.M. Smith

Abnormal GI Flora May Be Linked To Obesity

Researchers from Cedars Sinai Hospital in Los Angeles, California, presented data at Digestive Disease Week (May 2010) showing that GI flora may be different in those with a higher BMI.  They found specifically that individuals with higher BMIs have more methane-producing bacteria.  The lead researcher in this study has proposed that higher methane levels in the gut may slow digestive motility and allow for absorption of more calories from a meal.

Reference:
LA Times, May 6, 2010

Whey Protein Improves Satiety and Blood Sugar

When used before a meal, a dose of 10 to 40 grams of whey protein may decrease food consumption and improve post-meal blood sugar and insulin levels.

Researchers studying the impact of dairy proteins on satiety, found that giving whey protein in advance of an "all you can eat" meal, caused young adult subjects to eat less, feel more satisfied and have healthier blood sugar and insulin levels.

Reference:
Effect of premeal consumption of whey protein and its hydrolysate on food intake and postmeal glycemia and insulin responses in young adults
Am J Clin Nutr 91: 966-975, 2010
http://www.ajcn.org/cgi/content/abstract/91/4/966

Omega-3 Fatty Acids and Obesity

New research published in the British Journal of Nutrition has shown that people with lower body mass indexes (BMI) have higher blood levels of essential fatty acids such as EPA and DHA.  The researchers looked at 124 subjects and classified them by BMI as normal weight, overweight, or obese. Obese people had omega-3 levels of 4.53 per cent, compared to 5.25 per cent in their healthy-weight peers.  Researchers do not yet know whether essential fatty acids play any role in helping people to lose weight or to maintain weight loss. It is not clear from the results of this study if the link is causal or a simple correlation, however researchers are hopeful that future studies will help to answer these questions.  Essential fatty acids are known to support other areas of health such as brain, eye and cardiovascular health.

Source: British Journal of Nutrition
Published online ahead of print, doi: 10.1017/S0007114509382173
"Plasma n-3 polyunsaturated fatty acids are negatively associated with obesity"
Authors: M. Micallef, I. Munro, M. Phang, M. Garg

Dietary Fish Oil and Weight Gain

A study published in December 2007 in the Journal of Nutrition compared two groups of mice on high fat diets. In one group, 8% of the fat calories came form fish oils high in Omega-3 fatty acids, in the other it did not. The high fish oil group gained less weight and metabolised more fat than the control. The high fish oil diet was further found to improve fat metabolism-related enzyme activity, including fatty acid beta-oxidation, omega-oxidation, and malic enzyme activities in the small intestine.

Mori T, Kondo H, Hase T, Tokimitsu I, Murase T. Dietary fish oil upregulates intestinal lipid metabolism and reduces body weight gain in C57BL/6J mice. J Nutr. 2007 Dec;137(12):2629-34.

Childhood Obesity and Coronary Artery Disease

A study appearing the the December 6, 2007 issue of the New England Journal of Medicine significantly connects childhood weight to adult risk of coronary artery disease. Danish researchers looked at 277,000 children born from 1930 to 1976 and found that those with higher BMIs were significantly more likely to have heart disease as adults. Researchers further predicted that with the global rates of childhood obesity rising, that this will lead to a potentially epidemic rise in adult coronary disease in the next 3 decades.

Baker JL, Olsen LW, Sørensen TI. Childhood body-mass index and the risk of coronary heart disease in adulthood. N Engl J Med. 2007 Dec 6;357(23):2329-37.

Multivitamins May Support Healthy Weight Loss

November 2007 - Two studies published in late November the British Journal of Nutrition indicate that taking a multivitamin and mineral supplement may assist in weight management. The first study reported on a survey of survey of 267 men and 320 women aged 20 to 65. The survey found that in men regularly taking a dietary supplement weighed less, had less body fat, and lower BMI than those who did not. Women reported similar results, as well as generally reduced appetite.

In the second study, obese patients were placed on a low calorie diet and either given a multivitamin or placebo. While both group lost weight equally, those taking the multivitamin reported significantly reduced hunger both between and after meals.

G.C. Major, E. Doucet, M. Jacqmain, M. St-Onge, C. Bouchard, and A. Tremblay. Multivitamin and dietary supplements, body weight and appetite: results from a cross-sectional and a randomised double-blind placebo-controlled study. Br J Nutr. 2007 Nov 1;:1-11

Dairy Calcium May Help Slim Adolescent Girls

MANOA, Hawaii -- Scientists at the University of Hawaii have linked dairy calcium intake with lower iliac skinfold thickness (a measure of body fat) and body weight, according to a study published in the August 2004 issue of the Journal of Nutrition (134, 8:1905-09, 2004).

The study examined the body fat and weight of 323 Pacific Islander and Asian girls, aged 9 to 14 years, in relation to age, ethnicity and physical activity. Subjects were surveyed for mean age, calcium intake, weight and iliac skinfold thickness.

Calcium intake, age and physical activity were found to have significantly negative associations with iliac skinfold thickness, whereas height, Tanner breast stage and Pacific Islander ethnicity were found to have significantly positive associations. One mg of total and dairy calcium was significantly associated with lower iliac skinfold thickness and one milk serving was associated with 0.78 mm iliac skinfold thickness. Nondairy calcium was not associated with weight or iliac skinfold thickness. In addition, soda intake was significantly positively associated with weight in both models.

The researchers concluded decreasing soda intake and increasing dairy consumption among Asians may help maintain body fat and weight during adolescence.

"The future belongs to those who prepare for it."

- Ralph Waldo Emerson