Low-Carb Or Low-Fat Diet: Which One Is Better For Fat Loss?

People in the bodybuilding industry have been saying for years that there are more alternative solutions to one problem. Today, we’re working on the problem of obesity and the necessary weight loss. These people have witnessed that a number of dietary solutions are possible when overweight people start going to the gym. There are multiple ways to lose weight and improve your health, but in the media and gym culture out there, this answer has been considered insufficient.

The debate has been between eating a low-carb diet and eating a low-fat diet to get the job done, and so far we haven’t come up with a winner, even though the debate has been going on for decades. New studies come and go and each of the groups wants to use them to finally settle the discussion, but so far no decisive blow has been struck.

The last study to come into this debate is the one studying obese patients at Tulane University. The media pumped up the results of this study to mean that the low-carb group had won the discussion since low-carb diets were “found” to make you thinner, quicker. Even LeBron got mixed up into it somehow. Anyway, the low-carb group also delivered results that said that having that type of diet made you less susceptible to various factors of heart disease. At first, this may seem very important and a grand discovery because people on diets low on carbs and high on fat have been long considered to be riskier patients and more prone to heart disease. However, this was not the case and should not be celebrated with bacon and deep-fried cheese just yet. Let’s see what happened here.

How Was the Research Conducted?

This trial targeted obese people in Louisiana, but since the previous study for low-carb diets had included a very low number of people of color, this trial was made much more representative, with over 50% of the subjects being people of color. The demographers did make a mistake though – there were almost no Latin-Americans in this trial and zero Asians. Furthermore, over 90% of the enrolled people were women, so this study was in no way representative for men. That being said, here’s what they told the two groups to do:

  1. THE LOW-CARB GROUP was told to eat an amount of carbs smaller than 40g per day, for a year. Also, they were told not to change their activity levels and were given dietary counseling and meal replacements.
  2. THE LOW-FAT GROUP was told to eat less than 30% of daily calories in fat, for a year. They as well, were instructed not to change their activity levels and were given dietary counseling and meal replacements.

You can see a distinct number here – why 40 grams of carbs per day? That seems like an amount that only a diehard low-carb dieter would eat, and since previous studies had people eating about 100 grams of carbs daily, this turned out much better. Also, 40 grams is two slices of bread, so it’s easier to measure. However, taking someone who has been eating greasy American food for the better part of a century and putting them on a low-carb diet, things can become vague and unpredictable. In order to remedy this, the groups were given two more points to take care of:

  1. MEAL REPLACEMENTS. Each participating member was given a daily meal replacement bar or shake that was either low-fat or low-carb, in accordance with their prescription’s needs.
  2. COUNSELING. There were small sessions of group counseling with a dietician that told the people about dietary guidelines. Also, this was a great place for support.

When you take these two into consideration, you’re probably thinking nobody could possibly mess up the results, right? Wrong. Over four fifths of the participants completed the study, which is really high for a study of this type, but the calories they ate weren’t measured and controlled, and people sticking to the diet were self-reported, meaning they could have easily lied. My point is, the methods that were used here weren’t really scientific. Proof of this is that on average, the subjects reported eating about 2000 calories per day before taking up the new diet, and this not only seems inaccurate, but impossible. Remember that the study was conducted on obese people and take this information with some reserve.

So What Happened?

Well, instead of a low-carb and a low-fat diet, the researchers gave the people diets that barely classified as these things. The low-carb one wasn’t really low-carb and the low-fat wasn’t low-fat. Let me explain. The people were only instructed to eat 40 grams of carbs and report back, however nobody ever managed to eat that little. The first three months were the most beneficial since the people in the low-carb group cut from an average of 240 grams of carbohydrates per day, to just about a hundred grams. After the first three months, this number started rising and ended up just short of 130 grams of carbs per day after a full year of the program. So, if they somehow cut their carb intake in half but not really successfully, they must have increased their intake of other macronutrients, right? Of course. They ate the same amount of fat they did before the study, but they ate much more protein than before, jumping from 18 percent of their daily caloric intake to over 25 percent, which is way more protein than the amount consumed by the low-fat group.

The low-fat group wasn’t really low-fat either. I say this because it wasn’t really different than the normal American diet in terms of fat consumption. They started their fat intake at around 35 percent of their daily caloric intake, and then lowered it to fewer than 30 percent, which was great. However, since they cut the fat out of their diet, they also cut calories, about 500 of them per day. This meant that they consumed about 30 grams of fat per day, which isn’t a small amount of fat when it comes to calories! So, when it was time to replace the lost calories, they turned to carbohydrates, of course! They cut calories just as well as the low-carb people, but they ate a ton of carbs – over half of their total calories! Here’s what happened to both group’s bodies when compared to their previous bodily states.

  1. The low-carb group lost an average of 11.7 pounds per individual, 1.2% of fat mass was lost and 1.3% of lean mass was gained per person.
  2. The low-fat group lost an average of 3.9 pounds per person, with 0.3% of fat mass lost and 0.4% of lean mass lost.

The most exposed result in the media was the one that the low-carb group had far greater weight loss than the low-fat group, but the results were very different from person to person. The low-carb people also had a nice little boost in lean mass, but the low-fat group lost lean mass instead of gaining any. But, we have to look at the facts here – their body composition was measured by something called bioelectrical impendance, which is a very variable method, so you have to take these results with some reserve.

Even if the study doesn’t go into great detail when it comes to the mechanisms of researching the results, we know why the group that ate fewer carbs did better than the one that ate less fat when it came to lean mass gain and overall weight loss. This group ate a far smaller amount of carbs every day, slightly more protein and the same amount of fat, as opposed to the piles of carbs with the low-fat group. Also, when you factor in that a higher protein intake boosts weight loss, you start to think it might not have been the carbs or the fat alone – it’s all one big picture instead.

Heart Disease Predictors With Low-Carb Diets

The group that ate low-carb diets had a higher HDL to total cholesterol ratio than the group that ate low-fat diets. This is a very important predictor in the matter of avoiding heart disease. Also, the low-carb group had significantly lower triglycerides and a lower calculated heart disease risk score. Also, their LDL dropped more significantly more than that of the people in the low-fat group. Finally, the low-carb group had a significant drop in C-reactive protein, which is used to measure inflammation in the body.

So, as you can clearly see, the predictors of heart disease seem to have been bettered with the low-carb diet, even if the people in it consumed much more saturated fat than the people in the low-fat diet – over twice as much as the recommended amount, actually. Also, you should know that people in the low-carb group ate about the same amount of calories from fat as they did before they entered the study, and this means the same amount of saturated fat as well. So what does this mean? Can you finally get that deep-fried cheese and bacon? Nope. It means that when everything else stays the same, eating less fat is less beneficial than eating fewer carbohydrates, when it comes to heart disease predictors.

What Are We to Make of This?

Well, first we have to understand that there is no clear good or bad answer resulting from this study. It is still very unscientific and done without proper research modes, but there is a lot to learn from it anyway – it is, after all, a research study. Here’s what you can sum up.

  1. Weight loss can be achieved in a number of ways, and the one thing that matters the most is eating fewer calories over a longer period of time. A meta-analysis that was published the same week that this research was published said the exact same thing. The author of our study, Dr. Lydia Bazzano even agreed with the meta-analysis! Even if the two groups didn’t really cut their carb and fat intakes drastically, they did lose some weight over the course of the entire year just by cutting some calories.
  2. The inefficiency of helping techniques such as meal replacement bars or shakes, as well as nutritional counseling, may not be enough to get obese people to dramatically change their style of living. These techniques can help them boost their results, but never to start them up or comprise a main portion of the causes behind them.
  3. If you eat enough protein, it will help with your weight loss, even if you’re not changing anything else about your diet.
  4. If you cut your carbs you will lose weight and won’t have an increased risk of heart disease, so you may as well do it.
  5. When you put these last two together, you find out that this study indicated that if obese people cut their carb intake, that might be an indirect cause for them to boost their intake of dietary protein, which will help them with their weight loss. Eating fewer carbohydrates and more protein is a good way to lose weight, but the study didn’t really look into how exactly these two interacted with the body and what causes them to have this effect.
  6. All in all, eating less or causing any sort of dramatic dietary change is really difficult! When you’re telling people that have been eating the standard American diet for decades, that they should cut or remove one thing from their diet, which is probably one of their favorites, you’re going to have a lot of resistance! It takes real discipline to eat fewer than 40 grams of carbs per day if you’ve been living on cheeseburgers and fries for 50 years!

Note that a lot of people are never going to get that sort of carbohydrate reduction, and sustaining it is not an option for many of them, but even if their carb intakes go down, they will rarely go under 100 grams per day, never even getting close to drop the average under 100 grams. This means that the two camps will continue their fights based in dogma, since while these research results might have certain traits that we would consider valid, they still don’t prove anything. We still consider all macronutrients to be perfectly valid and the low-carb or low-fat groups still have a lot of debating to do, but this one may be considered as one little point for the group in favor of the low-fat diet because of heart disease predictors.

references: Effects of low-carbohydrate and low-fat diets: a randomized trial. (Bazzano LA, Hu T, Reynolds K, Yao L, Bunol C, Liu Y, Chen CS, Klag MJ, Whelton PK, He J.)


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