Mothers Who Limit TV Time Have Slimmer Kids

            How much time kids spend with entertainment media is strongly linked to weight. More TV time generally means higher body weight. Many research studies have consistently shown this over the years. The possible reasons are many. More television watching may mean less physical activity. Watching television while eating may be related to “mindless eating” and eating more calories. Food advertising during children’s programs is aggressive and effective and the ads push sweet, high calorie foods like candy and sodas.

            However, can parents influence, for the better, the effects of media on their kids?  A new study shows that the answer may be “yes”. Researchers followed 112 mothers and 103 fathers of 213 children. They interviewed the children and their parents at ages five, seven, and nine and gave them physicals at each of those ages. They found that the children of mothers who did not monitor their entertainment viewing tended to be heavier at age seven than at age five. They also found that weight in general was more irregular over the whole study period with less motherly media monitoring. Fathers’ media monitoring did not have any influence on their children’s weights. The effects of the mothers’ monitoring were independent of the parents’ BMI, education, and income. So that means the media monitoring itself was related to lower body weight!

            This is an important study because it shows that parents may be able to influence their children’s weight by actively monitoring and restricting how much time they spend watching TV and playing video games. There may be other good reasons to limit your children’s media use. Studies show that too much media may also be linked to attention problems, eating and sleep disorders, and, of course, obesity. Too much media can have such a negative impact on our children’s health that the American Academy of Pediatrics actually has guidelines for how much media kids should be using.

The American Academy of Pediatrics Media & Children Guidelines:

• All entertainment media should be avoided for infants and children under 2 years old

• Have a “screen free zone” meaning no entertainment media in children’s bedrooms or during dinner

• Limit Children & Teens to 2 Hours or Less of High Quality Entertainment Media 

• Encourage Children to Play Outside, Read, and Play Games

• Set an Example By Limiting Your Own Media Time

       This study has its limitations. This kind of study cannot show cause and effect but there did seem to be a link between mothers’ media monitoring and their kids’ body weights. The study was done in Oregon and most of the children were Caucasian so we don’t know if these results apply other ethnic areas or geographic locations. Parents reported on their own behaviors and how much TV their children watched so they may not have provided completely accurate information. 

Beth Kitchin, PhD, RDN
Assistant Professor, Nutrition Sciences
University of Alabama at Birmingham

References:

American Academy of Pediatrics. www.aap.org. accessed 3/24/14.

Tiberio SS, Kerr DCR, Capaldi DM, Pears KC, Kim HK, & Nowicka PN. 2014. Parental monitoring of children’s media consumption: the long-term influences on body mass index in children. JAMA Pediatrics online.

These Old Bones Aren’t as Old as You Think!

            Dolly Parton sings “These old bones will tell your story, these old bones will never lie”. But your bones only tell part of your story because every 10 years, you have a completely new skeleton. This is a little known “factoid” that I love relaying to my patients in the UAB Osteoporosis Prevention and Treatment Clinic because it’s really kind of cool.

                We think of our bones as being with us throughout our lives but your bones are in a constant state of flux. Cells called “osteoclasts” break down old bone and make way for cells called “osteoblasts” to come along and build new bone in its place. The rate of this “bone remodeling” ends up replacing much of our adult bones from the previous ten years! So if you’re 45, your skeleton is not really made up of any of the same bone you had at 35.

                This bone remodeling also paves the way for bone loss and possibly osteoporosis later in life because as we get older the osteoclasts speed up and the osteoblasts slow down. In other words, we are losing more bone than we can replace. For women, this is a particular problem as our estrogen levels drop with menopause. Estrogen slows down the osteoclasts (the cells that break down old bone) so when we lose estrogen we lose bone much more quickly. Getting older also speeds up bone loss in both men and women.

For more information about osteoporosis visit our virtual clinic at www.uab.edu/toneyourbones

Beth Kitchin, PhD, RDN
Assistant Professor, Nutrition Sciences
Patient Educator, UAB Osteoporosis Prevention & Treatment Center
University of Alabama at Birmingham

Exercise: The Best Medicine

A very interesting article was just published in the British Medical Journal. The researchers reviewed meta-analysis studies that compared exercise and medications to each other or placebo and the effects they had on the risk of death. Collectively, these studies suggest that exercise and medications have similar outcomes when it comes to lowering death. 

A quick lesson about Meta-Analyses:  Any time you see an article that talks about results of a meta-analysis, you should proceed with caution!  A meta-analysis is tricky business. Researchers combine data from several studies and reanalyze it as one study. They do this when there are few large, definitive studies in a specific research area. So they take a bunch of studies that meet their specific criteria as far as study design, research variables, study participant characteristics, etc. and crunch the data together. This method is imperfect at best because no matter how similar studies may be, the differences in how the data were gathered can result in much less precise results when you put all the data together. That said, these studies can be useful in areas where larger studies are lacking.  And if the researchers conducting the meta-analyses use rigorous methods, then the data can at least be somewhat useful. 

What this study found: The results of this particular meta-analyses are particular interesting and encouraging. The researchers looked at studies that looked at deaths related to heart disease, stroke, heart failure, and pre-diabetes. The risk of all of these diseases can be lowered by diet and exercise. But no one has ever shown if exercise by itself can reduce the risk of dying from these diseases or if exercise is as effective as medicines in lowering the risk of dying from these diseases. 

For heart disease and prediabetes, the researchers found that exercise was just as effective as medicines for preventing deaths caused by these two common diseases. In the case of stroke, exercise was found to be more effective than medicines in preventing death from stroke. 

What kind of exercise? Because the studies reviewed were meta-analyses, the exercise programs in each of the studies were different. Most used a combination of muscle strengthening exercises and aerobic exercise like walking, biking, or swimming.

The exciting message – that we do have to approach with caution – exercise may be as effective – and in some cases more effective – than medicines when it comes to treating several  of the diseases that Americans are most likely to die from. Since medicines can be expensive and have possible side effects, this is a good news message. And don’t forget that exercise has other benefits as well such as improving mood and your ability to do the day to day activities you need and want to do.

Beth Kitchin, PhD, RDN
Assistant Professor,Nutrition Sciences
University of Alabama at Birmingham

Naci, H. & Ioannidis, J. Comparative effectiveness of exercise and drug interventions on mortality outcomes: metaepidemiological study. 2013. BMJ 347:f5577.

Extra Protein May Minimize Muscle Loss During Dieting

The Study  One of the big challenges of losing weight is preventing muscle loss. When you lose weight by cutting calories, you always lose some of that as fat and some of that as muscle. But you want to minimize that muscle loss because muscle burns more calories than fat and also helps to keep you strong.

In a recently published study, researchers showed that when study participants on a weight loss diet were put on twice the recommended level of protein, they lost more fat and less muscle than the participants at the recommended level of protein intake. Participants who ate three times the amount of recommended protein did not get any extra benefit.

Everyone lost weight in the study – about 7 pounds for the people on the lower protein diet and just under 6 pounds for the people on the double protein diet over 21 days. But the people on the lower amount of protein (the recommended level) lost 58% of their weight as muscle while the people in the 2x protein group only lost 30% of their weight as muscle. The other 70% of weight lost was as fat.

Some cautions on this research:

• Small Study.  There were 12 to 14 people in each of the study groups – that’s small and those 12 to 14 people may not be like the rest of us! 
• Short Study. The weight loss portion of the study only lasted 21 days – so we can’t say what would happen long term.  
• Was it the protein? It is possible that because the people in the double protein group lost a little less weight, that the lower weight loss itself could have accounted for losing less weight as muscle.

So this finding is not conclusive by any means but it does raise this idea that we may be able to minimize muscle loss on a low calorie diet by boosting protein.

Protein Recommendations  So what is the recommended level of protein now? It is 0.8 grams of protein per kilogram of body weight. To change your body weight from pounds to kilograms, you divide by 2.2. So the protein needs for someone who weighs 220 pounds looks like this:

220/2.2 = 100 kilograms body weight    

100 kilograms x 0.8 grams/kilogram of protein = 80 grams of protein

So, if this person wanted to lose weight, you would double that to 160 grams of protein a day. Now things get a little complicated at this point because the rest of the diet also has to be adjusted to accommodate this increase in protein. Just increasing your protein intake won’t help you lose weight. In fact, you would probably gain weight from the extra calories!

So, you have to lower your overall calorie intake to a reasonable level that will help you lose weight. Then, you have to calculate how much fat and carbohydrates fit into your diet. In this study, the researchers had the participants eat less than 30% of their calories as fat and then added the rest of the calories in as carbohydrate. The bottom line is that you may want to consult with a registered dietitian to help you devise a plan that is accurate and works for you! Getting all that extra protein may not be as easy as you think. Here’s a list of the top dietary sources:

Best Protein Sources:

4 ounces of lean meat: 28 grams
1 cup skim milk: 8 grams
1 egg: 6 grams
4 ounces Greek yogurt: 12-14 grams
1 ounce of cheese: 7 grams
½ cup tofu: 10 grams
1 cup soy milk: 6 grams
½ cup pinto beans: 7 grams

Beth Kitchin PhD, RD
Assistant Professor Nutrition Sciences
University of Alabama at Birmingham


Source: Pasiakos, S. M., Cao, J. J.,Margolis, L. M., Sauter, E. R., Whigham, L. D., Mc-

Clung, J. P., Rood, J. C., Carbone, J. W., Combs, G. F.,Jr., Young, A. J.

Effects of high-protein diets on fat-free mass and muscle protein synthesis following weight loss: a randomized controlled trial. FASEB J. 27,

3837–3847 (2013). www.fasebj.org

Short on Sleep May Mean More Calories – and Weight Gain

     Over the past several years, the evidence that points to lack of sleep as a contributing factor to overeating has increased. In a 2010 study, researchers put 10 overweight participants on a moderately low calorie diet and then let them sleep up to either 8.5 hours or 5.5 hours for two weeks. They then switched participants to the other sleep group for another two weeks. They measured weight and body composition (fat vs. muscle) after each two period.  

Here’s what they found:

• More Sleep, More Fat Loss. When people got more sleep, they lost more of their weight as fat (3 pounds vs. 1.3 pounds) and less of their weight as muscle (3 pounds vs. 5 pounds).
• Less Sleep, Higher Hunger. When people got less sleep, they were hungrier. Their levels of a hormone called ghrelin were higher than when they were allowed to sleep longer. Ghrelin is a hormone in the stomach that makes you hungry.

      A study published last year in the Annals of Internal Medicine gives us a clue as to how a lack of sleep contributes to insulin resistance – which can lead to obesity and heart disease. The researchers found that when people were sleep deprived, their fat cells ability to respond to insulin dropped by about 30%. 

      But both of these studies were very small and inconclusive. Now a study published in this month’s edition of the journal Sleep, adds to the data. And this was a big study – 225 people. In this study, the researchers found that the people who were allowed only four hours of sleep over 5 consecutive days ate 500 calories above their needs a day and gained about 2 pound over the following 9 days. The people who were not sleep deprived did not eat extra calories above their needs nor did they gain any weight.  This was a short-term study so we cannot say whether these changes would remain over the long haul.

      Now, getting more sleep alone is not going to make you fit into your bikini in time for summer vacation. For one thing, not everyone is sleep deprived and not everyone who is sleep deprived overeats as a result. But lack of sleep could be contributing to America’s weight problem. The Centers for Disease Control reports that over 20% of Americans are getting 6 or fewer hours of sleep a night – well below the seven to nine we need.

So here are some tips to get the best sleep:

• Stay Calm Before Sleep: avoid caffeine, alcohol, troubling reading, and over stimulating, violent TV at bedtime
• Avoid Energizing Activities Before Bed: avoid exercise and bright lights around bedtime; try dim lights, meditative thoughts, and warm milk (yuck!).  A warm bath right before bed can help with sleep. Computers and cell phones seem to stimulate brain activity so avoid them before bed!
• Set the Stage: make sure your bedroom has curtains that are heavy and keep your room dark.
• Make Sleep a Priority:  just like you make time for your family, exercise, and eating, making the time to sleep should be just as important.

Now if only we could find a way to add more hours to the day!

Beth Kitchin PhD RDN

Assistant Professor, Department of Nutrition Sciences

University of Alabama at Birmingham

Sources:

Nedeltcheva AV et al. Insufficient sleep undermines dietary efforts to reduce adiposity. Ann Intern Med. 2010;153:435-441.

Broussard JL, Ehrmann DA, Van Cauter E, Tasali E & Brady MJ. Impaired insulin signaling in human adipocytes after experimental  sleep restriction: a randomized, crossover study. 2012; 549-557.

Spaeth AM, Dinges DF & Goel N. Effects of experimental sleep restriction on weight gain, caloric intake, and meal timing in healthy adults. Sleep. 2013