A brand new study performed by the Harvard School of Public Health and published in a recent issue of the The New England Journal of Medicine finally lays to rest the age-old question of which diet is the most effective for weight loss. So if you’ve got a couple of extra pounds you’d like to shed, should you reduce the amount of carbs in your diet? Increase amounts of fruits and vegetables? Reduce protein and animal fats? This study provides the definitive answer, and the simplicity of the “secret” it reveals will surprise you.
From October 2004 to December 2007, a total of 811 overweight adults in Baton Rouge and Boston participated in a study designed to evaluate the effectiveness of diets consisting of varying amounts of proteins, carbohydrates, and fats. In other words, they were trying to determine whether people on high protein/low carb diets (like the Atkins Diet) lost any more or less weight than people on high carb/low protein diets (like the Mediterranean Diet).
Most of the studies that had been done in the past were either, (1) relatively short term in duration (1 year or less), or (2) underrepresented a specific population group (usually men), or (3) were funded by a company with a direct financial stake in the outcome. These are usually the reasons that the conclusions of past studies tend to contradict each other. This new study attempts to address the shortcomings of past research.
The Harvard study was performed over a more than 2 year time span at the Harvard School of Public Health/Brigham and Woman’s Hospital in Boston and at the Pennington Biomedical Research Center of the Louisiana State University System in Baton Rouge. The group of adults were between 30 and 70 years of age and had a Body Mass Index (BMI) of 20 to 40. Approximately 40% of the study group were men.
The subjects were divided into 4 groups and each given a diet with different levels of carbohydrates, protein, and fats. The diets ranged from low fat/low protein, to high fat/high protein. Besides the composition of the diet, each diet represented a decrease of about 750 calories from the average daily intake of the participants. During the study, the participants also had a weekly goal of 90 minutes of moderate exercise and they attended group counseling sessions.
After about 6 months, it was found that the participants assigned to each group had lost an average of about 13 pounds (6 kg), which represented approximately 7% of their initial body weight. However, after about a year, it was found that they had regained some of the weight. By the end of 2 years, the weight loss had stabilized and remained similar across all of the diets. Among the 80% of participants who completed the study, the average weight loss, regardless of the type of diet, was about 9 pounds (4 kg). It was also found that all of the diets improved health risk factors and insulin levels equally.
So what can we conclude from this study? Despite all of the scientific jargon, what can we take away from this and use in our daily lives? Here are a couple of conclusions that I have come up with based on what I read in the study as well as my own experience (note: these are my conclusions – not necessarily those listed in the study):
- One of the conclusions noted in the study is that “Reduced-calorie diets result in clinically meaningful weight loss regardless of which macronutrients they emphasize.” Amen to that. The key to weight loss is to reduce the total number of calories you consume. Let me say that again. If you want to lose weight, eat less. This study shows that it really doesn’t matter what you eat, just that you eat less of it.
- Weight loss begins at the kitchen or restaurant table. I see people headed to the gym in order to “lose weight” all the time. Sorry, but you don’t lose weight at the gym. You can lift weights or ride the exercise bike all day long — and exercise is definitely an important part of any health plan — but you’ll never lose any weight unless you learn how to limit your serving sizes and push yourself away from the kitchen or restaurant table while there’s still food on your plate. Weight loss happens at the table, not at the gym.
- The body can adapt to just about any kind of diet. This study proves that it really doesn’t matter what kind of food you eat. Whether you eat mostly salads or Twinkies, organic health foods or junk, if you reduce the number of total calories you normally consume, you will lose weight.
- The study included having the participates attend regular counseling and group sessions. They found that there was a direct correlation between attendance and weight loss. What does this prove? It proves that your chances of losing weight go way up if you have a friend or support group to help keep you on track.
- Exercise is a critical part of any weight loss program. Why? I think it’s because when you’re exercising, you’re not snacking or being tempted to snack. It really doesn’t seem to matter what kind of exercise you do. Whether it’s a hard-core cardio routine or a leisurely walk around the block, the point is to get up off the couch, get away from that bag of potato chips that’s been calling your name, and get out and do something that gets you physically active.
- Ya gotta want to. The study found that the people that lost the most weight were the most motivated. Big surprise, right? But it still brings up a valid point. To fix any problem, you first have to admit it exits – and then commit to doing something about it.
- Permanent weight loss is a long term process. Sorry, but there is no “overnight” solution. There is no “lose weight fast” answer. PERMANENT weight loss is a 1-2 year process. In other words, “dieting” or making the right choices about what and how much you eat, should be a permanent part of your lifestyle, not an event that you undertake once or twice a year.
- If they can do it, you can do it. Of the 811 people that participated in the study, 80% of them completed the study. That’s about 650 people. 80% is a fantastic success rate and it shows that if they can do it, you can do it. All it takes is reducing your total daily calories by around 750 calories. That’s cutting out 1 bag of potato chips (150 cal), a soft drink (155 cal), 1 donut (200 cal), and a bowl of chocolate ice cream (225 cal) from your diet. Besides cutting down on snacks, you can find lots of areas where you can painlessly reduce calories such as getting a smaller portion size, leaving off the gravy, choosing baked instead of fried foods, and so on. Remember, if they can do it, you can.
So there it is. Nothing really earth shattering or surprising. If you want to lose weight, forget the fad diets. All you have to do is simply consume fewer calories.
You can read the full details of the study here: “Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates”
The Balanced Health Guy
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