By Tom Venuto, NSCA-CPT, CSCS
The new study, titled, “Weight Loss With a Low-Carbohydrate, Mediterranean, or Low-Fat Diet” was published in The New England Journal of Medicine (NEJM) in issue 359, number 3.
I quickly read the full text of the research paper the day it was published. Then, I shook my head in dismay as I scanned the news headlines. I found it amusing that the media turned this into a three ring circus, putting a misleading “low carb versus high carb,” “Atkins vindicated” or “Diet wars” spin on the story. But that’s mainstream journalism for you, right? Gotta sell those papers!
Just look at some of these headlines:
- “Study Tips Scales in Atkins Diets Favor: Low Carb Regimen Better Than Low Fat Diet For Weight And Cholesterol, Major Study Shows. “
- “Low-Carb and Low-Fat Diets Face Off “
- “The Never-Ending Diet Wars”
- “Low Carb Beats Low Fat in Diet Duel.”
- “Atkins Diet is Safe and Far More Effective Than a Low-Fat One, Study Says”
- “Unrestricted Low-Carb Diet Wins Hands Down”
Some of these headlines are hilarious! I wonder if any of these reporters actually read the whole study. Geez. Is it too much trouble to read 13 pages before you write a story that will be read by millions of already confused people suffering the pain and frustration of obesity?
Here’s a quick look at the study design.
The low fat restricted calorie diet was based on American Heart Association guidelines. Calorie intake was set at 1500 for women, 1800 a day for men with 30% of calories from fat, and only 10% from saturated fat. Participants were instructed to eat low fat grains, vegetables, fruits and legumes and to limit their consumption of additional fats, sweets and high fat snacks.
The Mediterranean diet group was placed on a moderate fat, restricted calorie program rich in vegetables and low in red meat, with poultry and fish replacing beef and lamb. Energy intake was restricted to 1500 calories per day for women and 1800 calories per day for men with a goal of no more than 35% of calorie from fat. Added fat came mostly from nuts and olive oil.
The low carb diet was a non-restricted calorie plan aimed at providing 20 grams of carbs per day for the 2 month induction phase with a gradual increase to 120 grams per day to maintain the weight loss. Intakes of total calories, protein and fat were not limited. However, the participants were counseled to choose vegetarian sources of protein (more on that bizarre-twist shortly).
The study subjects were mostly male (86%), overweight (BMI 31) and middle age (mean age 52)
Here were the study results:
There were some health improvements in cholesterol, blood pressure and other parameters in the Mediterranean and low carb group that bested the high carb group. That was the focus of many articles and discussions that appeared on the net this week. However, I’d like to focus on the weight loss aspect as I’m not a medical doctor and fat loss is the primary subject matter of this website. All three groups lost weight. The low carb group lost 5.5 kilos, the Mediterranean group lost 4.6 kilos and the low fat group lost 3.3 kilograms…. IN TWO YEARS! Whoopee!
My conclusion would be that the results were similar and that none of the diets worked very well over the long term!
Amanda Gardner of the US News and World Report Health Day was one of the few reporters who got it right:
“Diet plans produce similar results: Study finds Mediterranean and low-carb diets work just as well as low fat ones.”
Tara Parker-Pope of the New York Times also came close with her headline:
“Long term diet study suggests success is hard to come by: In a tightly controlled experiment, obese people lost an average of just 6 to 10 pounds over two years.”
Even this headline wasn’t 100% accurate. The study was HARDLY tightly controlled. Tightly controlled means metabolic ward studies where the researchers actually count and control the calorie intake.
The problem is, you can’t lock people in a hospital or research center ward for two years. So in this study, they used a food frequency questionnaire. Sure, like we believe what people report about their eating habits at restaurants and at home behind closed doors!
“No! I swear Dr. Schwarzfuchs! I swear I didn’t eat those donuts over the weekend! I stayed on my Mediterranean diet. Honest!”
One of the most firmly established facts in dietetics research is that almost everyone underreports their food intake BADLY, sometimes by as much as 50%. I’m not saying everyone “lies,” they just forget or don’t know. In fact, this underreporting of calorie intake is such a huge problem that it makes obesity research very difficult to do and conclusions difficult to draw from free-living studies. Another blunder in the news reports is that this study didn’t really follow Atkins diet parameters OR even the traditional low fat diet for that matter, so it’s not an “Atkin’s versus Ornish” showdown at all. If you actually take the time to read the full text of the research paper it doesn’t say ANYTHING like, “Atkins is the best after all.” That’s the spin that some of the news media cooked up (and what the Atkins foundation was hoping for). It says, “The diet was based on the Atkins diet.” However, the sentence right before that says, “The participants were counseled to choose vegetarian sources of fat and protein.” Vegetarian Atkins? The chart on page 236 says the low carb diet provided 40% of calories from carbs at 6, 12 and 24 months. If I’m reading that data properly, then the only low carb period was a brief induction phase in the very beginning. Does that sound like Atkins? 40% carb sounds more like the Zone diet or my own Burn The Fat program to me.
The Atkins Foundation, which partially supported this study, told reporters, “We feel vindicated.” HA! They should have paid the reporters and told the researchers they felt ripped off and they wanted a refund for misuse of their research grant!
After carefully reading the full text of this study, there are many interesting findings we could talk about, from the differences in results between men and women to the improvements in health markers. Here’s what the study really says that stood out to me. It’s what I would have talked about if the newspapers or TV stations had called me:
1. “Mediterranean and low carb diets may be effective alternatives to low-fat diets.”
I can agree completely with that statement. All three diets created a calorie deficit. All three groups lost weight. Low carb lost a little more, which is the usual finding because low carb diets often control appetite and calorie intake automatically (you eat less even if you don’t count calories). Also, if body composition is not indicated, there’s an initial water weight loss that makes low carb diets look more effective in the very early stages.
2. “Personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions.”
Absolutely! Nutrition should be individualized based on goals, health status, body type, activity level and numerous other factors. Different people have different phenotypes. Some people are more predisposed to thrive on a low carb approach. Others feel like crap on low carbs and do better with more carbs or a middle of the road approach. Those who dogmatically follow and defend one type of diet or the other are only handcuffing themselves by limiting their options. Iris Shai, a researcher in the study said, “We can’t rely on one diet fits all.” Hmm, far cry from “Atkins wins hands down,” wouldn’t you say?
3. “The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years.”
THIS was the part of most interest to me. When I read this, immediately I could have cared less about the silly low carb versus high carb wars that the news reporters were jumping on. I wanted to know WHY the subjects were able to stick with it so well. Of course, that’s boring stuff to journalists… adherence? What does that word mean anyway? Yawn - not interesting enough for prime time, I guess. But it was interesting to me, and I hope YOU pay attention to what I found. The authors of the study wrote:
“This trial suggests a model that might be applied more broadly in the workplace. Using the employer as a health coach could be an effective way to improve health. The model of group intervention with the use of dietary group sessions, spousal support, food labels, and monthly weighing in the workplace within the framework of a health promotion campaign might yield weight reduction and long term health benefits.”
Hmmmmm, lets see: * Dietician coaching
* Group meetings
* Motivational phone calls
* Spousal support
* Workplace monitoring (corporate health program)
* Food labels - calorie monitoring
* Weigh-ins (required and monitored)
Wow, everything helpful to long term fat loss that sticks. Can you say, ACCOUNTABILITY? These factors help explain the better adherence.
By the way, the adherence rate for the low carb group was the lowest.
90.4% in low fat group
85.3% in the Mediterranean group
78% in the low carb group
Here’s the bottom line, the way I see it:
First, please, please, please learn how to find and read primary research and take the news media stories with a grain of salt. If you want to know who died, what burned down or what hurricane is coming, tune in to the news – they do a GREAT job at that. If you want to know how to lose weight or improve your health, look up the original research papers instead of taking second hand information at face value.
Second, those who prefer a low carb approach; more power to them. Most studies, this one included, show at the very least that low carb is an option and it’s not necessarily an unhealthy one if done intelligently. I also have no qualms with someone claiming that low carb diets are slightly more effective for weight loss, especially in the short term, free living situations. Is low carb superior for fat loss in the long haul? That’s STILL highly debatable. It’s probably superior for some people, but not for others.
Third, low carb people, listen up! Even if low carb is superior, that doesn’t mean calories don’t count. Deny this at your own peril. In fact, this study shows the reverse. The low carb group was in a larger negative energy balance than the high carb and Mediterranean group (according to the data published in this paper), which easily explains the greater weight loss. Posting the calories contained in foods in the cafeteria may have improved the results and helped with compliance in all groups.
When energy intake is matched calorie for calorie, the advantage of a low carb diet shrinks or disappears. For most people, low carb is a hunger management or calorie control weight loss advantage, not metabolic magic (sorry, no magic folks!)
Fourth, choose the nutrition program that’s most appropriate for your personal preferences, your current health condition, your genetics (or phenotype) and most important of all… the one you can stick with. Then tend your own garden instead of wasting time criticizing how the other guy is eating. Your results will speak for themselves in the end. Take your shirt off and show us.
If I were forced to choose only one approach (and thank god I’m not), I would recommend avoiding the extremes of very low carb or very low fat or very high fat or very high carbs. Balance makes the most sense to me, and the research suggests that this helps produce the highest compliance rate. That’s not rocket science either, it’s common sense. If you have a serious fat loss goal, as when I compete in bodybuilding, then a further reduction in carbs and increase in protein makes perfect sense to me as a peaking diet. If an extremely low or extremely high carb diet worked for you, great. But generalizing your experience to the entire rest of the world makes no sense. Arguing from extremes is the weakest form of argument. The reason I have THREE nutrition plans (three phases) in my own fat loss program is because programs with flexibility and room for individualization beat the others hands down in the long term. In fact, I wrote an entire chapter in my e-book about unique body types, how to determine yours and how to individualize your nutrition – it’s THAT important. If you have more choices, you have more power. The people who are shackled by dogma and narrow thinking are stuck. They also risk missing what’s really important.
Train hard and expect success,
Tom Venuto CSCS, NSCA-CPT
Fat Loss Coach
PS. If you want to learn more about a balanced, flexible and proven approach, which teaches nutritional individuality and which can produce similar weight loss in one month, month after month, that the subjects of this study produced in TWO YEARS, (if you ADHERE to it!), then visit my fat loss website.
About the Author:
Tom Venuto is a natural bodybuilder, certified personal trainer and freelance fitness writer. Tom is the author of "Burn the Fat, Feed The Muscle,” which teaches you how to get lean without drugs or supplements using secrets of the world's best bodybuilders and fitness models. Learn how to get rid of stubborn fat and increase your metabolism by visiting: www.burnthefat.com