Tuesday, July 30, 2013

Myths, Assumptions, Nuances and Obesity

I have been writing about health and wellness in one form or another for 13 years. During that time I have gone to graduate school twice.  
My plan for the blog has always been to present information to the public that goes beyond the headlines.
My goal is to educate the reader in the hopes that he or she will take new science and recommendations for better health into consideration.   These recommendations include consuming a quality diet, getting sufficient exercise, limiting sedentary activity and maintaining a weight lean enough to prevent diseases that are associated with adiposity - or over fatness.

My understanding of research has improved over the years, especially the last few, but the science into the causes of obesity (adiposity) has been plagued with flaws.  Scholars far more experienced and critical than I, have begun to point out these flaws.
I tell you this because I am sensitive to the fact that I may have perpetuated false claims in my own blog or given too much credibility and attention to tenuous claims.  This exactly opposite my goal.  

Here I am speaking about diet quality and healthy weight.
It IS still about calories and the sources of those calories, but it is much more nuanced.  By nuanced, I mean that numerous factors are independently and interdependently related to health and weight.  

There are many problems with the methods used in obesity research and that makes it hard to pull together evidence that can suggest a solution.  Science has taught us a lot. We now need to use more precise measurement methods (e.g. with dietary recall, and body fatness), be consistent with our definitions (what is obesity?) and have more open minds about what the causes could be (is it really just too many calories ?).

This was wonderfully explained by Herbert et al (2013) in a commentary published in the journal Mayo Clinic Proceedings.  The summary can be found here.  They give good advice for improving research.  I will apply this advice in my career.

I will continue to talk about calories (food energy availability) and policies, but these are small parts of a very complex, multi -facted system.

Let me quote from the Herbert article.  I assure you that I believe every word in this paragraph.
...obesity arises from the dynamic interplay of the external environment, inclusive of the social milieu, built environment and food energy availability, behavioral and development processes and a variety of genes and epigenetic effects that, in turn, control a myriad of metabolic systems and subsystems that regulate energy intake, energy expenditure and nutritional partitioning.   
Now I will do my best to restate this in simpler terms:

There are many factors both inside and outside of our bodies that work together to create a condition where obesity is likely.  As one factor changes one or more others reacts and these changes and interactions are continual (dynamic). The external environment can make it easy or hard to be physically active (built environment) and easy or hard to eat too many calories (especially nutrient poor ones) (i.e., food energy availability). These two factors are also impacted by social cues (preferences, norms, advertising, ' peer pressure' - i.e., the social milieu).  Behavior is what we do - exercise or not, choose certain foods or drinks, and development is the body changing over time.  Genes, or heredity, are usually activated by some interaction with the outside environment (epigenetics) and together impact how the food a person eats is processed by the body - whether or not one gets high cholesterol, or diabetes for example.

That is a lot to process.  The simplest truth is that one should not eat too much, and a very complex set of circumstances determines if one eats too much and whether their eating too much causes a bad outcome (illness).   I would point out one last thing from the article.. the authors say that it is social and environmental factors, NOT genes, that have had the greatest influence.

So here are 3 interesting links about calories.
Link 1 This is a story about peoples desire for calorie information and how some restaurants are starting to provide lower calorie meals.  It actually summarizes a lot of the research I have used in my literature reviews and in this blog.  I love how it mentions Dardens Restaurants use of nutritionists and calorie counts when creating new entrees.  Also, it points out some REALLY high calorie entrees ~ over 2000.  Oh one problem, the writer keeps referring to the national menu law as a proposed law.  The law is a law.  It has been passed.  The rule - how to follow the law, is being proposed. 
Link 2  This links to a 3 item quiz on which item has the lowest amount of calories... I scored 100.
Link 3  This links to a story about smoothies and juices, both of which I personally avoid at all costs.

Friday, July 26, 2013

Do calorie recommendations make a difference in calories purchased?

   I want to mention a few things from the study I cite below.  Here is the most important one. A conclusion statement in the summary is misleading.  The statement, "Posting calorie benchmarks had no direct impact..." implies that the benchmarks were posted on the menu or menu board, but they were not. The study did not assess the effect of posting daily or per meal calorie recommendations (i.e., the benchmarks) ON A MENU.  It tested the effect of handing someone a piece of paper with this information on it as they walked into a restaurant.  That is a huge difference.  The researchers do not try to say otherwise.  It is just the one sentence that is wrong.  Unfortunately, a lot of people will not read the study to find out the difference.  In addition, it is that conclusion that most of the popular press headlines are touting.
   This was not a study on whether or not menu labeling works.  The study tested the effect of telling someone how many calories they might need in a day and the effect of telling them how many calories they might need in a meal.  In other words, would  people given either piece of information purchase a lower amount of calories than people not given any information.  (This was tested in a situation where calories were listed on menus and in a situation where calories were not listed on menus. That condition did not make a difference.)
    The slips of paper they handed the customers did not seem to help.  But I caution you not to conclude that the information isn't helpful.  There is a big difference in a menu board disclosure and a piece of paper someone hands you.  Still, it fuels my argument for something more powerful and less mathy... traffic light labeling. 
   There was something else I found interesting in this study.  The researchers asked the customers how many calories a doctor or nutritionist would recommend that they consume in a day.   Both men and women substantially UNDER estimated their own caloric needs, by 200 or 300 calories.. and YET, they ordered enough to far exceed their own estimated daily number.
E.g.,  a person who thought they needed 1100 calories for a whole day ordered 900 calories for their lunch.  Again, too much math.  Too much thinking at the point of purchase when other factors, like taste, cost, time, etc are more important.  (isn't it crazy that people think they need 1300 to 1600 hundred calories when our packages refer to a 2000 calorie diet AND people tend to actually consume 2000 or more a day  - more than most people need)
   STILL, the menu item calorie information should be available to every one every where.  Consumers have the right to know what they are eating. However, the best chance for changing the number of calories purchased may come when the restaurants start revising their recipes and the calories AVAILABLE to us become fewer.  Traffic light labels and lower calorie meals.. that's the ticket :)

 (Also, note - the people in this study were all eating at McDonalds.. there might be something about McDonalds customers that is different than other restaurant customers)

Article cited:
Downs, J. S., Wisdom, J., Wansink, B., & Loewenstein, G. (2013). Supplementing menu labeling with calorie recommendations to test for facilitation effects. American Journal of Public Health, e1-e6. doi: 10.2105/AJPH.2013.301218

Sunday, July 21, 2013

Fat in food vs Fat on your body

    I was frustrated by the research study on M&Ms. I was frustrated because it is 2013 and I thought we had learned that low fat is not the answer to our collective weight problem.
   Studies that continue to focus on promoting low fat choices add to the confusion.
As someone who has expertise in public health nutrition, health education and health promotion, I must try to clear this up. 
   Fat in food does not equal fat on your body.
   Too many calories from any source does. When a person regularly consumes more calories than their body needs, the extra is stored as body fat.  (Note: Over indulging every weekend is regularly consuming too much.)  There are ways to increase your intake to build lean body mass but that is not the focus here.

YES it is true that there are more calories in a gram of fat than there are in a gram of carbohydrate, protein or alcohol.   (9,4,4,7)  
YES it is true that some foods are more nutritious than other foods.  It is recommended that we fill our plates with nutrient dense, not energy dense, foods 
    Foods that are especially important are complex carbohydrates (vegetables and many fruits), whole grains and so called 'healthy' oils or fats (like those in olive oils and salmon).
Complex carbohydrates contain phytochemicals, flavinoids, and antioxidants.  These substances have been associated with reduced risk of many chronic diseases.
And YES it is true that refined or simple carbs, like sugar, white flour (rice, pasta, bread) baked goods, sugary or starchy fruits with little fiber, and all sugar sweetened beverages have more calories than they do nutrients.
AND Yes, it is true that some sources of fat just like some sources of carbs are believed to be harmful. (e.g., red and processed meats are associated with colon cancer).
   The reason some foods are calorically (energy) dense is because they are full of sugar or fried in grease.  
   Too many calories from either  = fat storage. 
    And because its politically palatable to promote, physical activity as a solution to the country's obesity 'problem,'  I have to address that too.  Initiatives to build more parks and alert people to "take the stairs" are only going to work (for weight control) if two things happen.  TWO things.

1) people actually start using the stairs and parks, and
2) they stop eating too much

It does not matter how many stairs a person climbs (Mayor Bloomberg), if he or she eats more calories than needed - weight loss will not occur if 'we' keep eating too much.

There are people (fewer than the drug/genetic companies would have us think) who fall outside these generalities.  In other words, some people do not gain weight no matter how much they eat and others do not lose weight not matter how much they restrict.  These are very unusual people and I suspect you are not one of them. 

Disclaimer: I am not a nutritionist or a dietitian who can give individual diet advice.   I share information based on research and public health recommendations.

Tuesday, July 16, 2013

M&Ms: Labels, Calorie Estimates, and Calories Eaten

   This month, researchers Ebneter et al published the results of a study that explored 4 outcomes related to labeling and calorie disclosure.  I am only going to tell you about 2 of the outcomes. One is the amount of calories consumed and the other is the amount of calories the people 'guessed' were in a serving size.  Outcomes 3 and 4 are not a research interest of mine.  For your information, they were 'taste perception' and 'perception of healthiness.'
   The study was an experiment that took place outside of a natural setting.  The people involved in the study were all undergraduate female college students attending a Hawaiian university.  I tell you this so you can consider how much you are like the people who were in the study.
   For the experiment, the researchers placed the women in one of 4 rooms.  Each room had a bowl of uniquely colored M&Ms.  The women were told that they were taking part in a taste test.  A card was set next to each bowl of M&Ms. One card said Low Fat M&Ms and nothing more.  One card said Low Fat M&Ms and one serving (~55 pieces) has 240 calories.  A third card said Regular M&Ms and nothing more and the last card said Regular M&Ms and gave the same calorie information.  (There was no actual difference in the M&Ms).
   The researchers weighed the bowl before and after each of the 175 women went into a room (one woman at a time per room). They gave the women 15 minutes to do the taste test and then removed the items. When the items were gone, the researchers asked the women to estimate the number of calories in a serving of the M&Ms they had tasted. 
   Here is what they learned. (NOTE: the differences might have been by chance alone, i.e., there was not a statistically significant difference between the numbers).
   People with a low fat label ate more calories than those in the regular label group. People without a calorie label in the low fat condition guessed the calories per serving lower than 240.  People without a calorie label in the regular label condition guessed the calories too high (more than 240).
   I will let you think about that.  My concern is the focus on high and low fat when the problem (in general) is consuming too many calories.  I am especially concerned that people mistakenly think low fat is low calorie AND that people do not know how many calories is low or high.  I believe that this study doesn't support the use of low fat labels as much as it supports the use of a traffic light label.  With a traffic light label we can put a big red circle around the fat grams and the calories.
    Here is a nutrition facts panel for a bag of M&Ms - I don't think they make 'low fat' ones.  M&Ms are high in fat - but have 3 times as much sugar as fat!
   There are several labels out there, but according to Mars, the maker of M&Ms, a package this size has 240 calories, 10 grams of fat and 30 grams of sugar.

Here is the study citation.

Ebneter, D. S., Latner, J. D., & Nigg, C. R. (2013). Is less always more? The effects of low-fat labeling and caloric information on food intake, calorie estimates, taste preference, and health attributions. Appetite, 68(0), 92-97. doi: 10.1016/j.appet.2013.04.023

Friday, July 12, 2013

See how the type of nutrition label impacts your understanding.

I have spoken of front of pack nutrition labels many times and provided examples of different systems.  A system can be one that appoints stars for meeting a certain criteria, or one that uses a symbol to denote healthiness, or my favorite, one that uses a multiple traffic light.  The multiple traffic light system shows whether the product is low, medium or high in amount of each nutrient most people should limit (i.e., sugar, salt, sat fat and calories).
The most important thing about a front of pack label is that it be standardized across all products, manufacturers and restaurants (if it goes to menu labeling).  Imagine how confusing it would be (and is now in the US) if each company decided what information, if any, to put on the front of a package.  
When it comes to making health and weight related dietary choices the most important disclosures are these: calories, sodium, sugar, and probably saturated fat. We need to be able to see the amount of these nutrients at a glance across items as we shop.  The traffic light system goes one better.  If the traffic light is used, a consumer does not have to do math or know the number of grams or milligrams that are recommended for any one nutrient in a daily diet.  The consumer just has to know that green is better (GO) and red should be limited or avoided (STOP).  In essence, a consumer can aim for mostly green and yellow.
The UK has begun its voluntary traffic light labeling program in grocery stores and it seems to be doing well.
When researchers and public health professionals were making the case for front of pack labels, they put together an on line quiz to test consumers understanding of nutrition labels.  It is still available, here.  I took it and suggest you do as well.  

Tuesday, July 9, 2013

What's your plan B?

**** post note.  I have been working on my 12 mile bicycle ride. (I am riding a mountain bike on the street -  they aren't fast on the street).  See how I my speed increased almost every time!   This is a fun, challenging way to survive a vacation from running.  Look at the column on the right, and start at the bottom.  I started at 12 mph and increased to 13 mph.

**original blog post:
No, not for birth control... your exercise plan B.
What do YOU do if you can't do what you planned to do?  What do YOU do if you can't do your planned exercise for one day?  What if you can't do it for weeks or months?

By now, you should be convinced that exercise is not something you do because you want to lose a few pounds (though it sure helps) but something you do to prevent disease, boost your mood and to age successfully (not normally - successfully).  In other words, exercise is not meant to be temporary.  It benefits you for as long as you do it (like healthy eating).

So if you have plans for a walk at the park and it rains, what is your plan B?  If you planned to swim, but a thunderstorm or faulty equipment closes the pool, what do you do instead?  Do you have a list of options for your plan B?

What if the activity you prefer, for me its running, is one you have to rest from?  IF you like to swim and tear a muscle in your shoulder that will take months to heal, what will you do for your exercise?

It is best to have more than one exercise - not just for plan B days, but in general.  This is because the body acclimates and what was once challenging can become ineffective.  The body needs variety  - could be little things like tempo, speed and terrain - and big things like alternating biking, swimming, running, walking, aerobics, sports, etc .

My usual routine is 5 days of running (with changes in place and pace) and two days of swimming (w/ 2 routines) and 2 days of weight training.  YES, that IS nine days.  You are very astute.  I swim and weight train on the same day.

Cycling is my plan B as is 'extra' swimming and step aerobics.  On a recent walk date, my friend and I got rained out, so we went to the mall and WALKED.  Corny, but effective. 

When the pool closes unexpectedly, I go to another pool, or I cycle or do some indoor cardio activity at the gym.  Sometimes I lift weights at home if the gym is closed on a weight train day.  ETC

Something else you might consider - especially if you are using exercise for weight control or perhaps, stress control, and you have to stop your high intensity exercise.  How do you handle the change in calorie burn that comes from decreased intensity?

You have a few options.  You can switch to low impact activities and do them longer, sometimes twice as long.  You can work on making that low impact activity, like cycling, walking or swimming happen FASTER. You can do the lower impact/low burn activity for the same time that you did your favored higher burn activity and choose to eat less - or you can do the low burn activity for the same duration and accept that you'll gain a few pounds.   (For me, I don't have more time to spend - but if I choose a 12 mile cycling routine, I can try to do it faster (even a few seconds) each time.  I would not be increasing distance, just pace.  For swimming, I could stick with my time limit, 50 minutes and try to get in more laps -so more distance)

 MOST important take home message - YOU DECIDE.  Take control and be ready with your plan B list.  You decide how you'll adapt to the change and you decide that this adaption does not include quitting.

Wednesday, July 3, 2013

Is a cold office the next new diet fad?

A recent study by Chen et al, suggests that a slight decrease in the air temperature increases calorie burn.  See the abstract from the study here.

Brief background: Our bodies contain two types of fat - or adipose tissue - brown and white. Brown fat is the kind that keeps us warm and is found in much greater abundance in babies and children than in adults.  It is referred to as BAT sometimes.

Adults have small amounts of BAT and when it is activated - to keep us warm - BAT takes its energy from white fat.  White fat is the kind that most of us are trying to lose.

In their small experiment, the scientists were able to measure this 'under the skin' BAT activity with a PET scan.  They found that when the temperature was lowered by just a few degrees, the volunteers' brown fat cells went into action.  The volunteers burned more calories (energy) under the lowered temperature than the 'normal' temperature.

As a person who never enters a building without a sweater and one who cannot afford to lose any of her white fat, I was not so happy with the authors comment....
this may represent a novel environmental strategy in obesity treatment.

I stay amazed at the lengths people go to in order to lose weight without having to eat less or move more..