What?! People who eat more carbs tend to be thinner?
We've been talking about how hard it is to draw valid conclusions and make recommendations about diet based on epidemiological data in this recent post on saturated fat. But this latest epidemiological study on carbohydrates and obesity is so provocative, I have to comment.
The study, published in the current issue of the Journal of the American Dietetic Association observed that the lower the percentage of carbohydrates in your diet, the more likely you are to be overweight or obese.
A few details:
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It was a big study, involving 4500 otherwise healthy people.
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It was a cross-sectional study, meaning that they simply took a snapshot of people's dietary patterns and their current body mass index. In other words, they weren't tracking changes in diet or weight over time.
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They adjusted for variables that might otherwise explain these results. In other words, the differences in weight are not due to differences in age, activity level, education, or income. And it wasn't that the people who ate fewer carbohydrates were simply eating more calories. They adjusted for total calorie intake, too.
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They did NOT have any data on what kind of carbohydrates (simple, complex, refined, whole, etc.) were consumed.
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Not surprisingly, people who ate a greater percentage of calories from carbohydrates ate more fruits and vegetables and consumed more fiber. Interestingly, those who ate more carbohydrates also ate a greater percentage of those carbohydrates as sugar--but perhaps this reflects in part the increased consumption of natural sugars in fruits and vegetables.
The researchers conclude that a diet containing 47 to 64% of calories from carbohydrates results in the lowest risk of obesity. That range will seem shockingly high to low-carb proponents, who recommend levels anywhere from 5 to 40% carbohydrate diets. However, it's worth noting that the conclusions line up almost exactly with the Institute of Medicine's recommended range of 45- 65%.
What to make of all this?
In an accompanying editorial, Christian Roberts and Simin Liu point out potential weaknesses in the study. People who reported that they were on "high protein" or "high carbohydrate" diets were excluded from the study, for example. (Then again, including these people might also have been cited as a weakness; it's a toss-up). They point out that the snapshot involved a single day's intake, which might not be representative.
Who knows? Maybe the study simply reflects the popularity (if not the effectiveness) of low-carb diets among those who are overweight. In other words, perhaps people who are overweight are more likely to be restricting carbs in an effort to lose weight. What we really need is ANOTHER shapshot of the same population six months or a year later to see whether the folks who were eating fewer carbs were getting any smaller!
When the study appeared on the newswires, I expected an immediate hew and cry from low-carb blogosphere but the low-carb camp has been strangely silent so far. Perhaps they consider the study unworthy of a response.
If you come across (or have written!) blog posts or articles in response to this study, feel free to post them below and I'll do the same.
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Posted by: Robert | Oct 11, 2009 8:41:21 PM
They need to solve the carb cravings some of us get on any carb....whole wheat or otherwise.
You all know it, one or two little rolls, and the whole bag needs to be eaten...or you sit in the corner craving them all night.
I'd rather have my bacon eggs and a vitamin and forget about food for 5 hours.
That's the wonderful part of low carb, you forget about food between meals most of the time! No more snacking, or cravings for the most part.
It's like liberation from food.
Posted by: laura | Sep 12, 2009 3:21:20 AM
well I mostly eat carbs and I totally lost weight thru this diet and I maintein my weight.And yes I'm thin (99 lbs).I hardly eat any meat...I mostly eat grains/fruits/vegetables and skimmed milk products~drinking only water and ocazionally green tea(no more than 1200 cals a day)
Posted by: Robert | Aug 13, 2009 2:44:16 PM
You can totally loose weight with high carb, BUT...you can't have much fat at all. The body will just store it if you don't immediately start working out afterwards.
Again carbs are not bad, but they do trigger hunger in some people REGARDLESS of the fiber glycemic mumbo jumbo.
It doesn't matter if I eat white bread or 700 grain ;) I will get hungry for more in 30 minutes and continue that way.
All I know is I've done low carb for 2 months now, feel fine, and down to a size 33 waist...and falling.
You wanna stay heavy and eating carbs...please do so...I'll look even better next to ya. ;)
Posted by: Robert | Aug 13, 2009 2:37:05 PM
And let us be frank, healthy snacks are good...but taste lousy to some of us.
I've eaten more green vegetibles on low carb then I EVER did in my carb lifestyle.
The reason is simple, a big piece of meat or fish etc., eaten WITH those veggies, with all the oil etc., TASTE FANTASTIC.
I gobble down mounds of spinach and radishes now with my meat, when during the carb days, I couldn't stand veggies.
Posted by: Robert | Aug 13, 2009 2:33:56 PM
Carbs beget carbs in many people.
Carbs are not bad, but humans did not develop in a carb rich world, and the food supply we have right now...has only been around for MAYBE 100 years...I mean vast sources for even the poor. Taking that into account...maybe only 60 years.
So we have a vast amount of carb rich foods, which we never really had in the history of our race. You will not find carb rich foods in nature, we grew it and made it, and agriculture has only been around 10k years or so, not enough to evolve..and certainly not enough time in 60 years to adapt to food bounty like now.
My ONLY reason for being on low carb, is because it is the only way of eating that curbs my hunger between meals. Low fat doesn't do that, I was always hungry, always angry, and dreaded exercise because I never had energy.
I have no problem walking a lot now, because I can eat all the meat and fat I want...so I feel rewarded instead of the never ending punishment in low fat/gym/exercise regime.
I've been very low carb for 2 months now, and no reason to go back. Aside from occasional energy spikes and valley's, and some mood swings (minor) I feel fine. They are just different symptoms of this eating compared to my old carb days. I felt lousy at times then too, but didn't realize it was the food doing it to me...just as this food does. It's just different symptoms of the lifestyle.
Posted by: Sue | Aug 11, 2009 4:01:24 PM
I'm sure high carb diets work for some, just as low carb diets are more appropriate for others, including myself. One unscientific study does nothing to change these facts.
Posted by: Joanna | Aug 7, 2009 10:48:39 AM
I'm also glad to hear some potentially good news about carbs. I have been always been a "higher carb" type of eater. I have never been overweight. Conversly, I know people who are low carb believers who either have not lost the weight they need to or are now more overweight!
Posted by: Angela J | Aug 3, 2009 5:02:11 PM
I just want to thank everyone for sharing. About a year ago I met someone who had alot of success losing weight. She taught me that we need carbohydrates, protein and fruits and vegetables in every meal we eat. She shared that our largest portion should be fresh fruits and vegetables, the next poriton should be carbohydrates and the smallest portion should be protein. Of course some of these groups overlap. She shared that each snack should be balanced and each meal should be balanced in the same manner. I tried this and lost the weight I desired to lose. It makes since that we give our body the fuel it needs and that we don't deny our bodies. I too was one who tried all types of diets. I wanted to try something that made sense and didn't require that I have to be slave to a pill or anything man made. This worked for me maybe it will work for others. I guess balance is the key... Understanding how protein, carbohydrates, and fresh fruits and vegetables benefit our bodies can lead to us making healthier food choices.
Posted by: Vondi | Jul 31, 2009 7:00:07 PM
This is completely crazy. My doctor put me on a low carb diet due to my proclivity for borderline diabetes. Specifically she "outlawed" all starchy carbs--ie breads, pastries, potatoes, pastas, etc.
I live with my daughter and son in law. Out of concern for my health my daughter said she would follow the same eating plan to keep me encouraged. Here's the thing! She has dropped two dress sizes and Ive dropped one.
This has resulted only from eliminating the starchy carbs in our diet and keeping others under 120g per day. No counting calories. No trying to 'lose weight.' Only following the doctor's orders regarding my carb intake.
I don't care what the study says, my daughter and I have disproven it without even trying.
Posted by: Casey | Jul 31, 2009 3:38:44 PM
As a registered dietitian, I find these posts entertaining. The overall general theme I've noticed from all the posts is that just because one eats food, then one MUST be a nutrition expert. Instead of arguing incessantly about good carbs - bad carbs - no carbs - slow carbs...how about visiting with an *actual* nutrition expert to obtain evidence-based information for a change? You might find it refreshing...
Posted by: Olivia | Jul 30, 2009 6:46:46 AM
All carbs are not equal. Are we talking white bread and pastry or beans and oatmeal here? Can we all agree that processed carbs are not healthful and whole grains are?
Posted by: CC | Jul 28, 2009 9:44:38 PM
I believe the most fundamental flaw in this study is that they are taking correlation and then attaching causality to it. Just because skinny people wear smaller pants doesn't mean that wearing larger pants causes a higher risk of obesity...
Posted by: RebelHealth Chick | Jul 28, 2009 8:12:07 PM
I have to agree with one of the commenter's above (Tigger) from at least a subjective standpoint. We are human beings, last time I checked, not robots or machines. Why does something have to be right or wrong when we're talking about the metabolism of food, specifically carbohydrates. What might work for one won't work for another. Genes, environment, activity level, quality of food, mental health, etc...all are factors in whether a high or low carbohydrate diet might work for some and not others, don't you think? Do we have to be so political? How about some bi-partisanship here!
Posted by: Josh | Jul 28, 2009 7:13:04 AM
In my opinion and experience, it does not matter how many carbs you eat. If the overall caloric intake per day is more than what you need, you will get obese in the end.
Posted by: Heidi Yoder | Jul 27, 2009 10:01:12 PM
Come on we have to be smarter than this. If you don't differentiate between the type of carbohydrates, then you can throw the study right out the window. Broccoli di cecco is carbohydrates. Pasta is carbohydrates. A snickers bar is carbohydrates. They all cause your body to react in very different ways. All I know is a few decades of low fat, high carbohydrate eating got us two generations of obese, diabetic children. Thanks for the above poster who spoke to the insulin issue. Just a reminder...high glycemic carbs=sugar in the bloodstream=insulin rush=everything stored as fat AND constant high levels of insulin means the brain no longer senses it as a reason to send out the message that the body is satiated. Insulin, like the word "carb", becomes meaningless. Eating mostly vegetables, some lean protein, a little fat and having treats such as pasta or dessert once a week is a sensible way of eating for an adult. And not so bad for a kid either.
Posted by: Philip Landwehr | Jul 27, 2009 7:07:05 PM
I do have to agree with some of the findings here, I try to eat a minimum of 40 grams of fiber per day.
And I do have to like what I eat.
I am losing approximately 2#/week.
Posted by: Marty B | Jul 27, 2009 6:43:59 PM
Well it makes sense to me!!! The key is CONTROLLED carb intake!! Not the hundreds/thosands that some of us eat, but maybe 1/3 of that! I have been on a high protein, very low carb & calorie DIET for 5 weeks and yes I've lost 22 pounds, but I am miserable!!
Posted by: Patrick M | Jul 27, 2009 6:27:31 PM
Just a quick comment on the Rice issue. You cannot compare one persons reaction to consuming rice with another persons. One person may have a proper portion 1/2 cup and another will have 2 cups. The larger the portion the greater the glycemic response. Thus more insulin is released. The greater opportunity for conversion to lipids and stored as body fat. Not to mention being hungry 30 minutes later due to the significant drop in blood sugar levels, due to the deluge of insulin. Everyone's tolerance is different.
Posted by: sharons | Jul 27, 2009 5:02:14 PM
I agree with courtney - eat a balanced diet of whole foods, cut out anything processed or that comes in a box ready to heat up and you've got a recipe for successful weight control and maintenance. Not to mention the health benefits of the lower sodium and lack of chemicals in whole foods.
Posted by: D. | Jul 27, 2009 3:58:32 PM
Some people can clearly eat carbs and maintain a healthy weight. Others, like me, can't.
Perhaps the real study that needs to be done is to investigate the difference between these two distinct group of people.
So often studies and diets presume the same result will apply to all people. This simply isn't true - people metabolise foods differently. So why do some people put on weight the moment they eat carbs? And why can others eat carbs and maintain a healthy weight? I'd like to see the results of a study on this.
Posted by: Richard | Jul 27, 2009 3:16:47 PM
Many good points mentioned here but I think the study is painting these food groups with to large a brush. Not all carbs are equal in my opinion. Sugar-sweetened sodas, candy, potato chips, Twinkies can not be compared to foods like steel cut oats, fruits and vegetables. We should also note that unrefined foods (that are considered healthier choices) are usually not all one type of material, i.e. carbs, protein but are a mixture of these nutrients. It seems to me that in most cases a balanced diet is the healthier one with the ratio of carbs, proteins, and fats balanced to meet the physical needs of the person. One size does not fit all.
Posted by: Pat merewether | Jul 27, 2009 2:44:08 PM
I think there are many kinds of 'bodies' and metabolisms and what works for one person (low carbs) might not necessarily work for another. If I eat too many starchy carbs, I gain weight like crazy, but I have friends and family who say they gain weight faster if they eat red meat. We each have to get to know our own body and figure out what's best for us.
Posted by: Jim Linderman | Jul 27, 2009 1:59:25 PM
Now at age 60, and 5 years later - after changing to "low carb" diet; I remain 25 pounds lighter (180) with great "numbers" in my lab work.
Protein, animal fat, etc is what our bodies were designed for ...
Posted by: Carol | Jul 27, 2009 1:57:21 PM
As with all of this - caveat emptor! As someone with Type 2 diabetes I scrupulously manage my "bad" carbs and embrace the "good" carbs which include those with high fiber and lower glycemic indexes. A can of pinto beans has much less impact on my blood sugar than a piece of chocolate cake. The take away is that not all carbs are equal - but then you all already knew that!!
Posted by: Nick | Jul 14, 2009 12:42:54 PM
I'm a competitive runner at a number of distances (5K's to ultramarathons depending upon the time of year), currently cranking out 90 miles per week.
I can tell you that around 65% of my calories are carbohydrates, if not more. I eat a reasonable amount of protein, a lot of it from vegetable and fish sources, and as a result do not consume very much fat. Without a large amount of carbohydrates, I simply can't keep up with this sort of mileage. They're fuel for the body! But, I honestly have no idea what these proper ratios are for me. I just make sure to eat as much protein and carbohydrates as I can before the next run, and you know what, it works wonderfully.
My point is this: there six billion different lifestyles and six billion different diets. And arguing so intently about macro-nutrient ratios without considering whether foods are wholesome, provide proper vitamins and minerals, etc., is folly.
Posted by: courtney | Jul 13, 2009 4:08:10 PM
a diet rich in carbohydrates being good for weight loss. absolutely!! if you control your calories and eat lots of whole grains, along with fruits, veggies, lean proteins and good fats, then you will lose weight.
i am a pescatarian and i also disclude dairy my diet. my diet is 47%-64% carbohydrates if not more and i'm actually underweight.
the key to keeping slim isn't cuting out carbs. it's choosing smarter carbs (whole grains have more fiber which will keep you fuller and less prone to snacking), controling calories and exercising. it's that simple.
Posted by: Bruno | Jul 12, 2009 2:28:27 PM
Why most of the people here think this study is not "valid"?I'm a vegan, 5'6/170 lbs 5.7% body fat, and I'm basically eating only legumes,raw veggies/fruits, raw nuts, and wholewheat pasta + oysters once a year ;)
Posted by: Mike | Jul 12, 2009 6:57:41 AM
I've been loosing weight with meal replacement morning and noon, then if hungry a healthy snack between. It worked so well I joined the sales team!
Take a look. www.shopherbalife.com/freeoffer
Deep discounts and free products
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Posted by: Sean | Jul 12, 2009 2:32:48 AM
aw, but guys...corporate run fabrications are so much fun! believe, believe!
[weston a. price + raw food = NIIIIICE]
Posted by: James Reno | Jul 11, 2009 3:07:02 PM
I am working on eliminating my diabetes through a raw food diet. It does not involve a lot of carbs. However it includes many nutrient dense superfoods.
To Your Health!
James Reno (editor)
Raw-Food-Repair.com
Posted by: Jennifer | Jul 11, 2009 2:15:19 PM
This study doesn't seem to differentiate between people who have been overweight and people who have never been overweight. I think that is like comparing apples to oranges, also genetics/ancestry plays a much bigger role then people realize. Tell an overweight pima indian that they should just relax an consume more carbs like their caucasion cohorts do and you can sit back and watch them die from diabetes. Once you become severely overweight to morbidly obese you are metabolically/pychologically different from people who have always been within the average weight range. I had a friend who lived for 6 years in Nepal in the peace core, she commented on when new volenteers would arive after a few months or so of a traditional Nepalese diet, about 80% carbs, some people would be walking around looking like scarecrows and others would have to keep the top botton on their pants undone as they blew up on the diet and then others who didn't seem to change much at all. There seems to be an assumption that there is a one size fit all diet that will make us all one size!
Posted by: Georgia | Jul 11, 2009 11:57:15 AM
I looked further down into the comments and I saw someone mentioning diabetes and insulin resistance. I want to make a comment about that as well.
DR Weston Price many, many years ago traveled about the world and studied hunter-gatherer cultures eating their native diets and compared them to modern American diet. What he found was a lack of modern western diseases including diabetes. Paleoarcheoloigists have also noticed this in studying bones of various cultures. Those cultures that did not eat grains showed no signs of diabetes, tooth decay or osteoporosis, while those cultures that ate grains definitely had these conditions. The research is out there. It's been out there for years. There are many researchers continuing this research. The grains that most notably cause this issue are wheat, barley and rye due to the gluten proteins they contain. 1 in 133 people can not break down gluten in their small intestine and it leads to a wide array of dysfunctions including diabetes. That number may even be higher. Many grains including rice, buckwheat (which is actually a fruit), oats, qinoa and tapioca do not contain gluten. They will not contribute to the diabetes problem.
Please do your homework people. The information is out there. Sadly many in the nutrition community are unaware of this knowledge. I blame that on the education system. Most nutrition programs completely gloss over Dr Price's landmark and extremely important research.
Posted by: Georgia | Jul 11, 2009 11:41:54 AM
The reason may be that the more carbs a person eats the less protein they get. Protein being the building block for everything in your body, the less you have of it the less you will weigh. on the surface that looks great, but in truth is very dangerous. Protein not only is used for your muscles but is also required for all your organs and all your hormones and neurotransmitters etc. It basically controls all your body functions. Lack of enough protein in your diet can cause malfunctions. I see it in vegetarian clients all the time
Plus measuring Body fat with BMI is an oxymoron. BMI does not measure fat. It was developed by a mathematician as a math puzzle and never intended to be used in a medical or fitness setting. here is a wonderful article on BMI http://www.npr.org/templates/story/story.php?storyId=106268439
Body fat percentage is the ONLY way to measure obesity. That the study uses BMI completely invalidates it.
Any conclusions drawn from the study are erroneous. How many other invalid assumptions did they use in this study???? Just because it is a published study does not make it valid.
Plus just because the people are thinner does not make them healthier. If they are deficient in protein or other vital nutrients because of their high carb diets sets them up for many diseases. I'm am absolutely horrified to see a professional lauding such an erroneous study on a site that people come to for facts on nutrition. I have to re-educate people on nutritional misconceptions constantly. Publishing something like that here just makes the issue that much worse. Shame on you.
Monica's Response: I hardly think my post could be read as "lauding" this study. One way to counter nutritional misconceptions is to encourage people to look beyond the headlines. I think the kind of discussion that is going on here is the best possible way to get people to start thinking more critically about the research that gets reported in the media. Thank you for your contributions to that discussion.
Posted by: Mike | Jul 11, 2009 2:25:33 AM
I am completely unsurprised. The claim that eating carbs automatically leads to insulin resistance is not at all valid.
Rice-eating Asians in their native countries do not have high diabetes and obesity rates. Even Michael Eades says in response something anathema to many low-carbers:
"A couple of things. First, I think Asians are a little better adapted to carbs than non Asians, brought about by many thousands of years of rice consumption. Second, carbs can be consumed without all the consequences if the calories are kept low. It is my understanding that the Asian diet is pretty low-calorie as well as being high-carb."
http://www.proteinpower.com/drmike/weight-loss/low-carb-diet-triumphant-over-low-fat-in-meta-analysis/
The diets mentioned in "The Blue Zones" by Dan Buettner all had unrefined carbs. When one researches Asian centenarians, one finds rice mentioned as a part of the diet in almost every article (suggesting that Buettner was not distorting the diets).
Some people who have damaged insulin systems may benefit from a low-carb diet, but at least some are carb-adapted (Barry Sears says 25%) and I wonder if perhaps nearly everyone is born able to handle at least unrefined carbs.
It does amaze me how belligerent some low-carbers can be at even a slight expression of dissent.
Posted by: Hillery | Jul 10, 2009 10:28:56 PM
Maybe I'm new to this and don't know what I'm talking about, but the whole thing makes sense to me. The key words are "Not surprisingly, people who ate a greater percentage of calories from carbohydrates ate more fruits and vegetables and consumed more fiber."
That sounds like the basis for an ideal diet to me. I never did understand how lowering carb intake at the expense of limiting fresh fruit and veg made sense. You can lose all the weight you want, but are you healthy?
Posted by: Tigger | Jul 10, 2009 5:31:59 PM
Why is there so much anger involved when people talk about carbohydrates? If you found a diet that works for you and makes you feel great, why does it make you so mad when others don't agree with you?
Posted by: Rhomboid | Jul 10, 2009 8:16:30 AM
If they are controlling for the total number of calories consumed then that means they're compensating for all the obese people that practically live off refined carbs from chips, candy, cookies, snacks, etc. *That* is what people who turn to low carb diets are really escaping from, and the study seems to have intentionally excluded this effect.
Or in other words, take the total number of calories out of the equation and assume it is constant -- then what is the difference between different diets? This completely sidesteps the issue that by avoiding refined carbs you also reduce your calorie intake.
Posted by: Melissa | Jul 10, 2009 2:45:19 AM
I have to say i read this twice and it really didn't make sense to me how these people can state that eating more carbs is better on the long run, KNOWING that excess carbs leads to insulin resistance and diabetes, high blood pressure among others! i've been leading a low carb life *not diet* for almost 2 years and i'm 5 pounds from my goal weight so what i think is i should write a new study and i bet you it will be more valid than what they're talking about here because i would actually be SERIOUS and THOROUGH!
Posted by: Raymond | Jul 10, 2009 1:23:34 AM
I actually think that this study makes sense. The problem with very low carb diets is that the body still craves the carbs it needs. So a person will go through a lot of food searching for those missing carbs. In contrast, somebody who does not restrict his carbs in that way, will immediately eat the carbs his body craves, thus avoiding all those other kinds of calories that the body did not really crave in the first place. I hope it is clear what I am saying here.
Posted by: wifezilla | Jul 9, 2009 6:08:32 PM
You're right. It isn't worthy of comment. When I ate a carbohydrate based diet, not only was I 80lbs heavier, I was hypertensive and on my way to a stroke. I have been low carbing 2 years and not only is my weight down considerably, my blood pressure has gone from 149/95 to 101/62.
