Research Roundup – Jan. 30 2013

Research Roundup!

Research Roundup!

Study #1: Too Little Sleep Spurs Appetite-Boosting Hormones

Process worked differently in men, women.

Sources: MedLine Plus

Jason’s Thoughts:

Lack of sleep impacts many aspects of healthy living, including appetite.  Sleep is when your body repairs itself, converts thoughts to long term memory and more.  If you’re getting less than 6 hours of sleep, you could make a healthy habit change by focusing on getting even 30 or 60 extra minutes of sleep a night.  Set a timer to stop working at a specified hour, create a routine, try to keep as much light out as possible (including your cellphone screen) and don’t do anything in bed except sleep (well, and that too) so your body doesn’t associate your bed with any other activity that could keep you awake.  If you have racing thoughts when trying to go to bed, write down all of your worries or concerns on a piece of paper until you can’t think of anything else to write.  Then try going back to bed.  Or you could do warm milk if you’re not lactose intolerant.

Study #2: Yo-Yo Dieting Can Hurt the Heart:

Older women who lose weight and then regain it may raise their risk of cardiovascular trouble.

Sources: Healthday and Journals of Gerontology

Jason’s Thoughts:

There’s always been debate on whether yo-yo dieting can have negative effects beyond the weight regain.  This study suggests yes, at least for older women.  I think it really ultimately comes down to the related changes in body composition.  If your weight loss comes from ½ muscle and ½ fat and your weight regain is primarily fat, then you have less lean body mass, a slower metabolism and likely more inflammatory issues going on in the body.

Samantha Heller, exercise physiologist and clinical nutrition coordinator , says it best in the article, “This small study is a great example of why we need to avoid fad diets and diet programs, potions and pills that promise quick weight loss … while it can be frustrating to take the slower, healthier route to weight loss, the long-term results are ultimately more satisfying and healthier.”

Living healthier is a skill that must be learned, or relearned.  It’s not about the speed of weight loss, it’s about permanency.  I want every pound lost to be one that never comes back.

All Diets Work…and that’s the Problem

Dieting Advice Confusion-meter!

Which Diet is Best? All…and none.
Photo: Stuart Miles at FreeDigitalPhotos.net

All research starts as good ideas.  And then research validates if those ideas are, in fact, any good.  Many ideas can be proven to achieve similar effects, in this case, weight loss or improved health. In other words, there’s more than one way to skin a cat…or lose 20 pounds and improve cardiovascular disease risk.

Company spokespeople cite the “latest” research about their diet and how it’s the best and how no one else’s compares.  I politely respond, b*llsh*t.  Ask a dietitian, or even trainer, how many times they’ve heard: “What’s the best way for me to eat to lose weight, or get healthier?”  Like we’re supposed to magically have the answer…not even the research proves a single “holy-grail answer.”  (beyond eat better and move more).  But we need to have an answer, because we’re the experts.

So here’s an answer; let’s prove that all diets work, even ones that blatantly contradict each other in approaches:

*Note: This list is long.  If you want to skip to the punch line, hit Page Down a few times.

Similar weight loss between a high-protein, low-fat & high-carbohydrate, low-fat diet: http://ajcn.nutrition.org/content/81/6/1298.full

Both low-fat and low-carb diets led to 15 pound weight loss: http://jcem.endojournals.org/content/89/6/2717.short

When total calories are held constant, low-fat and low-carb diets yield similar weight and body fat loss (better insulin, but worse blood lipids in high protein group): http://ajcn.nutrition.org/content/90/1/23.abstract

Weight loss was similar between a high-protein and high-carbohydrate group after an initial 3 months of calorie restriction (better blood pressure improvement in high protein group): http://ajcn.nutrition.org/content/90/5/1203.abstract

Just cutting fat out of the diet works: http://ajcn.nutrition.org/content/53/5/1124.full.pdf

Low-fat, high-fiber diet predicts long-term weight loss and decreased Type 2 Diabetes risk: http://link.springer.com/article/10.1007%2Fs00125-006-0198-3?LI=true

Low-fat diets improve cardiovascular disease risk factors: http://circ.ahajournals.org/content/86/1/1.full.pdf

Lower carbohydrate diets lead to weight loss: http://phdres.caregate.net/curriculum/pdf-files/nejm2k3-2074.pdf

Zone (40/30/30), Atkins (low-carb), Ornish (low-fat) and LEARN (lifestyle-behavior change) all resulted in weight loss.  Atkins had best results in 12 months: http://jama.jamanetwork.com/article.aspx?articleid=205916

Those who have achieved significant long-term weight loss tend to consume a low-fat, low-calorie diet (~23% of calories from fat): http://europepmc.org/abstract/MED/9550162

Low-fat, low-carb and Mediterranean diet groups all lost weight, low-carb and Med groups did better: www.fammed.usouthal.edu/JournalClub/Journal%20Club%2032609/WtLossWithLowCarbMediterraneanOrLowFatDiet–NEJM.pdf

A lower-fat diet led to weight maintenance in postmenopausal women over 7.5 years compared to a 4 pound weight gain in the control group: http://jama.jamanetwork.com/article.aspx?articleid=202138

Those following a moderate fat Mediterranean diet had better adherence to the diet than low-fat diets.  Average weight loss after two and a half years: 7.7 pounds. http://europepmc.org/abstract/MED/11673773/reload=0;jsessionid=KaU6kHUz52R7Ig82Xxw1.20

Just eating less foods high in fat leads to weight loss, but restricting calories AND fat does better (plus self reported exercise): http://europepmc.org/abstract/MED/8281220

Consuming a reduced-calorie diet across a range of nutrient levels [protein (15 to 25%), fat (20 to 40%) and carbs (35 to 65%)] 424 participants lost a similar amount of weight independent of nutrient composition.  Interestingly, 40% of the weight was regained within 2 years, independent of groups as well: http://ajcn.nutrition.org/content/95/3/614.abstract

Meal Replacements work, better than food-based diets initially (28 vs. 20 pounds lost in first 16 weeks)…until the meal replacements stop (12 pound vs. 2 pound REGAIN in the following 24 weeks).  www.biomedcentral.com/content/pdf/1475-2891-9-11.pdf

Dairy IS effective for weight loss:

Dairy IS effective for reducing inflammation: http://ajcn.nutrition.org/content/91/1/16.long

Dairy IS NOT effective for weight loss:

Soy IS effective for weight loss:

Soy and Inflammation:

Whole Grains PROMOTE health and weight loss:

Whole Grains and Inflammation:

Paleo Diet Improves Weight and Health Biomarkers:

Intermittent Fasting is as Effective for Weight Loss as Consistent Calorie Restriction

More Frequent Meals Lead to Better Control of Appetite and Weight:

Recap – Here’s the summative review:

All diets work, but the results last ONLY if you stick with them – if your “diet” becomes the true meaning of the word: your permanent eating habits.  Some interesting statistics from the studies above:

1.   Poor long-term adherence to most diet recommendations: The average dropout rate of participants in these studies were usually somewhere between 25 to 50% with most studies lasting less than 6 to 12 months.  Imagine that many people dropped out of your school or quit your job…makes you think people don’t want to be there.

2.   Modest long-term results: And studies that lasted longer than a year resulted in modest average weight losses around 5 to 10 pounds.

3.   Only 33% use better eating AND exercise for weight loss: In a comprehensive look of over 32,000 people in 1998, nearly one-quarter of men and 38% of women reported trying to lose weight.  Unfortunately, only one-third of the people trying to lose weight were actually trying to eat better AND exercise more:  http://europepmc.org/abstract/MED/15165656

4.   When food is more than just fuel: Few of these dietary interventions take into account people dealing with issues of emotional eating.

This article is one of the best reviews I’ve seen of weight loss for obesity and metabolic syndrome (pre-diabetes, cardiovascular disease, etc.) and their conclusion quote describes the situation well:

“As shown in this review, there are many dietary strategies focused on macronutrient distribution or micronutrient and food-enriched manipulation for the treatment of obesity and features of MetS features. However, the real challenge is to find the appropriate approach for maintaining body weight loss and preventing subsequent relapse, while simultaneously reducing cardiovascular risk factors.

The ideal diet should be personalized to each patient and should include those dietary factors that imbue healthy and satiating dietary habits that are beneficial not only for effective weight loss, but are also good for body-weight maintenance as well as for reducing cardiovascular risk. Thus, a currently available diet may be one that has a moderate protein content (30%), high monounsaturated and omega-3 FAs, low-GI carbohydrates (40%), and includes adequate quantities of fiber, isoflavones, calcium, and antioxidant minerals.  Since adherence to healthy dietary patterns can be difficult, meal replacement and dietary supplements should be considered as effective strategies for weight loss, weight maintenance, and treatment of MetS. Several factors such as genetics, physical activity, psychopathological conditions, obesity type, gender, age, or yo-yo cycles may influence the outcome of any dietary intervention. They should be taken into account as much as possible when dietary advice is prescribed for body weight management.”

From: Obesity and the metabolic syndrome: role of different dietary macronutrient distribution patterns and specific nutritional components on weight loss and maintenance (2010) by Itziar Abete, Arne Astrup, J Alfredo Martínez, Inga Thorsdottir, and Maria A Zulet

It’s still a matter of calories in vs. calories out…even if you choose not to count them.  The rub is, the equation is always changing on both sides depending on your base metabolism (which tends to decrease if you’re chronically undereating – to be discussed in further posts), your exercise levels and, of course, your eating habits.

Remember the question from earlier about the best diet to lose weight?  Here’s a better answer:

There are 10,000 ways to lose weight, but only one of them matters: the one that works for you.

The Wheat Belly Diet: A Relatively Independent Perspective

America: For Amber Waves of Grain?

America: For Amber Waves of Grain?
Photo by: -Marcus- at FreeDigitalPhotos.net

First, my best wishes go out to all who have been affected by Hurricane Sandy.  May we all take the results in stride and take solace in the friends and family we have.

With the development of a hyper-connected culture (internet, Twitter, FB, etc.), new ideas can spread like wildfire.  Last week I learned about two of these ideas: Gangam style and the Wheat Belly Diet, both of which landed over the summer.  Amazing how even a couple months lag time really puts someone “behind the eight ball.”  So, of course I started to catch myself up.  Lots of amusing Gangam style parodies and wow, quite the firestorm of information regarding Wheat Belly.

While I will be the first to admit I haven’t read the book, I feel that the sheer strength of response to any remotely negative views on the diet shows there is a staunch, loyal following, similar to that of Atkins in the 1970’s and 1990’s.  Check out these sites for some lively, not necessarily science-based discussions on the topic:

Pro-Wheat Belly Backlash to Healthy Eats Blog Post
Anti-Wheat Belly Backlash from the Celiac/Gluten Sensitive Community

My views on wheat and gluten-free diets were previously discussed hereIf you are at all considering this diet, please read this well-researched review of the statements in Dr. Davis’ book.

From reading the reviews of the book and the advertising behind it, it appears that the current state of wheat (GMO, processed, etc.) is being depicted as the worst thing you can put in your mouth.  Not sure if someone’s done a randomized control trial comparing wheat to cigarettes or alcohol, but maybe one day.  In all seriousness, do you think there should be a wheat-aholics anonymous?

I agree that most foods in their current, GMO, processed forms are a pale shade of what they used to be.  We are indeed living in a different world than the 1970’s.  But we’ve been eating and living with wheat for centuries, dare I say millennia, without ill effects (obesity has really only been an issue in the past few decades, per those CDC graphs).  One thing that has changed in the past few decades is the amount of wheat (particularly heavily processed, GMO wheat) and other processed foods we eat.  Breakfast pastries and “energy bars” did not really exist 40 years ago.  So our bodies have adapted to our new food environment, in less than ideal ways.

So some people choose to get out of this poor food environment cold turkey.  And that’s what Wheat Belly proposes.  Just stop.  Some people can manage to do that and that’s fantastic.  I’ll always support cutting out processed foods and eating more fruits and veggies.  And frankly, if you cut out (or greatly restrict) one huge aspect of your diet, odds are you will lose weight.  But there’s a big issue that comes with restriction: sustainability.

For decades research has shown that the more we restrict our eating habits, the less likely we are to stick with any positive eating changes we make.  I just want to make sure you’re able to sustain any changes you make for the long haul.  And by long haul I don’t mean 3, 6 or 12 months.  I mean the rest of your life.  While it’s great to hear that people have changed their lives around over the past couple of months since reading this book, I fear that in three years from now this book will become another “fad” diet.

So what’s the best solution?  Well that depends.  I’m a proponent of the belief that our bodies really do best with a variety of whole-foods including fruits, veggies, healthy fats, lean proteins and whole grains.  Not processed, crappy grains, whole grains.  And honestly, wheat falls under the whole-grain category.  Ideally organic, naturally grown, non-GMO wheat.  In moderate quantities (i.e. not wheat at every meal).   We can die from too much water.  But that doesn’t mean we should stop drinking water.

Who Should Eat a Gluten-Free Diet?

Whole Wheat: Friend or Foe?

Whole Wheat: Friend or Foe?
Image: FreeDigitalPhotos.net

*Warning: A long post, but please stick with me here and let me know what you think.

Gluten-free foods have become all the rage the past five years, from quinoa pasta to rice-based crackers.  Many people swear by eating gluten-free: more focus, weight loss, greater energy, you name it.  But do you really need to give up gluten entirely?  Understanding the causes of and differences (or lack thereof) between gluten intolerance, wheat/gluten allergy, gluten sensitivity and celiac disease is crucial, and that’s what this article sets out to explain, in laymen’s terms.  I will be citing a few references, but will also be providing a few personal “logical extensions” of what we currently know.  If you agree with me, great.  If you don’t, I’d love to know why (with appropriate competing references and rationale) because it helps me learn more.  But before we delve in too deeply I want to know: do you know what gluten is?

According to Wikipedia (they have a good definition!), “gluten is a protein composite found in foods processed from wheat and related grain species, including barley and rye” (and kamut).  So, gluten is one of the primary proteins in wheat.  Sometimes you will see oats on the “avoid” list for gluten-free diets as well because many grain-processing facilities in the U.S. process wheat and oats in/near similar machines, so cross contamination can occur.  However oats themselves do not contain the gluten protein that those with gluten intolerances are sensitive to.

On the Internet and throughout the media these days the words “gluten sensitivity,” “gluten intolerance” and “wheat/gluten allergy” are used quite interchangeably.  Researchers, on the other hand, use these terms to refer to specific reactions and levels of severity.

Wheat/gluten allergy: Creates a systemic allergic reaction similar to other food allergies like hives, nausea, congestion and even anaphylactic shock in severe cases.  Low prevalence, only about 1% of children (many grow out of it) and a few adults.

Celiac Disease: A severe form of gluten sensitivity. When someone with true celiac disease eats a food with gluten, the body’s immune system attacks the gluten in their digestive tract and causes the destruction of many of the cells that are responsible for food and nutrient absorption into the body (properly called villi/microvilli).  The resulting inflammation and gastro-intestinal distress (i.e. diarrhea, bloating, cramps, etc.) is largely dependent on the severity of the celiac disease. Other symptoms may include malnutrition and increased risk of osteoporosis and cancer.  There are specific tests to determine whether you have celiac disease, and those with the diagnosis require gluten-free diets to remain symptom-free.

Considering how many people out there are swearing by gluten-free diets, you’d think that a huge portion of the population has celiac disease.  What percent of the American population do you think has celiac disease?  20%?  10%?  5%?  According to a recent study of nearly 7,800 people in the American Journal of Gastroenterology in July 2012, the prevalence of celiac disease in the U.S. is 0.71%.  Less than three quarters of one percent.  Interestingly, 29 of the 35 people who had celiac disease were undiagnosed until the study!  Non-Hispanic whites were the highest sub-group with a rate of 1.01%.

And this is not limited to the U.S.  In Europe here are some percentages (people 30-64 years old):

  • In total, across 29,212 participants: 1%
  • 2.4% in Finland
  • 0.3% in Germany
  • 0.7% in Italy

Interestingly, another study showed that prevalence of celiac disease has increased four-fold in the past 50 years, from 0.2% to 0.8%.  However, is this a result of changes to our diets or more sophisticated detection processes?  Either way, celiac disease is relatively uncommon.  The conclusion of the first study says it all: “Most persons who were following a gluten-free diet did not have a diagnosis of celiac disease.”

So why are so many people eating gluten-free diets?  Are there other types of people sensitive to gluten that do not have celiac disease?  It seems like there may be.

Undefined/Un-diagnosable Gluten Sensitivity: According to an interesting article in the Wall Street Journal, about 6% of the U.S. population may suffer from “gluten sensitivity,” resulting in stomach discomfort, headaches/migraines, balance problems and more.  But these sensitivities cannot currently be diagnosed.  So how can we tell the difference between this kind of gluten sensitivity and celiac disease?  The author of the article provides a great distinction:

“Their immune reactions were different, too. In the gluten-sensitive group, the response came from innate immunity, a primitive system with which the body sets up barriers to repel invaders. The subjects with celiac disease rallied adaptive immunity, a more sophisticated system that develops specific cells to fight foreign bodies.”

In other words, gluten-sensitive people have a more generalized inflammatory response to deal with the presence of gluten (i.e. the entire body gets pissed off) compared to those with celiac disease, where the body specifically attacks the gluten and the parts of the body immediately surrounding it (i.e. the body attacks the GI tract where the gluten is located).

Here’s my breakdown of the current information/research:

The body is designed to protect against foreign invaders.  Those invaders typically carry particularly identifiable “proteins” that our body can sense.  In celiac disease, there is a very specific auto-immune response (there is a direct, measurable cause-and-effect of eating gluten and getting sick) where a person’s body attacks itself when they consume gluten.  Therefore they should follow a gluten-free diet.

For gluten sensitivity, however, the issue is much more murky. There’s no particular measurable antibody response, although people do tend to feel better when they no longer eat gluten-based foods.  This “primitive immunity” results in an increase in general inflammatory proteins, that are impacted by many other factors besides gluten (to be discussed below). So what’s going on?  Maybe we’re just getting too much of a good thing?

This is where I take a logical leap, follow me for a minute and let me know your thoughts:

About 40 years ago the U.S. (and in some ways the world) went on a HUGE whole-grain kick when people realized that eating white bread and white rice all day wasn’t the best thing.  The fiber, vitamins and minerals from the bran and germ portions of the grain were important.  So we started eating more whole grains.  And what type of grain did the U.S. have an abundance of?  Wheat!  Fields and fields of wheat (points if you got the Woody Allen reference!).

So we started having wheat cereal for breakfast, wheat-bread with our sandwiches at lunch, wheat crackers as a part of our snacks and eventually whole wheat pasta for dinner.  We couldn’t get enough wheat.  In general, the more we expose our bodies to a particular stimulus without giving it a chance to recover (even good stimuli), the more potential we have for a negative response from the body.

Take running, for example.  Going for a run a couple times a week is good.  Our body gets the stimulus, recovers and then is ready for the next run.  Now imagine going for two or three runs a day, every day for half your life.  Do you think your body will wear out and get pissed off and inflamed?  Now consider how often we eat wheat each day.

Is it just possible that we’ve eaten too much wheat and need to reduce how much of it we’re eating?  This is the essence of most food sensitivities.  Your body gets pissed off because you’ve had too much of a particular food over and over again (consider dairy as another one).  If you’ve eaten a ton of it you may need to greatly reduce or cut it out to allow your body to “calm down.”  But then you can probably add it back in reasonable portions.  How much you have is up to you and your body’s reaction, but you could probably have it at least a few times a week, maybe even once a day.  Just not three times a day.

I would also like to mention that since the inflammatory response in gluten sensitivity is non-specific, it is affected by many other factors such as stress (mental or physical), exercise, consumption of other inflammatory foods, drinking alcohol, heat and more.

Non-specific inflammation (which is what occurs in non-celiac gluten sensitivity) is very much like a pool filling with water.  There’s a drain at the bottom of the pool which is our body’s natural ability to process and deal with inflammation.  However, causes of this inflammation (i.e. non-specific gluten sensitivity, stress, etc.) are streams of water pouring in.  The body is able to handle a certain amount of inflammation based on our ability to process it.  Healthier habits such as sleep, staying active, drinking water and stress management tend to slow the flow of water in and increase the size of the drain allowing water to flow out.  On the other hand, unhealthy habits tend to make the water flow in faster and make the drain smaller.  We only show symptoms when the pool reaches a critical point where the water is filling in so fast that it begins to spill over the edges, since the drain cannot clear it out fast enough.

In those with gluten sensitivity, gluten is one of the things that causes the water to flow into the pool faster.  So unless you want to go the rest of your life without pasta or bread, the key is to determine how much gluten you can eat without having your pool spill over (a tip: do lots of other things that help increase the size of the drain at the bottom of the pool to keep inflammation levels down).

If you have celiac disease or a true wheat allergy, then you should consult a Registered Dietitian and doctor for nutrition counseling before making any significant changes to your diet.

References:

Beck, M. (2011). Clues to gluten sensitivity.  Wall St. Journal, Health Journal, March 15, 2011.  Accessed on 8/16/12 at: http://online.wsj.com/article/SB10001424052748704893604576200393522456636.html#

Hadjivassiliou, M. et al. (2010). Gluten sensitivity: from gut to brain.  The Lancet: Neurology.  9, 318-330.

Mustalahti, K. et al. (2010). The prevalence of celiac disease in Europe: Results of a centralized, international mass screening project.  Annals of Medicine.  42(8), 587-595.  Accessed on 8/16/12 at: http://informahealthcare.com/doi/abs/10.3109/07853890.2010.505931

Rubio-Tapia, A. et al. (2009). Increased prevalence and mortality in undiagnosed celiac disease. Gastroenterology. 137(1), 88-93.  Accessed on 8/16/12 at: http://www.gastrojournal.org/article/S0016-5085%2809%2900523-X/abstract?referrer=http%3A%2F%2Fscholar.google.com%2Fscholar%3Fq%3Dceliac+disease+prevalence

Rubio-Tapia, A. et al. (2012). The prevalence of celiac disease in the United States.  American Journal of Gastroenterology. July 31, 2012 edition.  Accessed on 8/16/12 at: http://www.nature.com/ajg/journal/vaop/ncurrent/full/ajg2012219a.html

Sapone, A. et al. (2011). Divergence of gut permeability and mucosal immune gene expression in two gluten-associated conditions: celiac disease and gluten sensitivity.  BMC Medicine.  9(23).  Accessed on 8/16/12 at: charlotteceliacconnection.com/files/Divergence_of_Gut_Permeability_and_Mucosal_Immune_Gene_Expression_in_Two_Gluten_Associated_conditions_-_BMC_Medicine_-_March_2011.pdf

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