Can I Get Fat On A Low-Carb Diet?

During my fat burning experiment to get a six pack in three months, I was able to explore the effectiveness of a low-carb diet with limited exercise. Looking at the results, it would seem that going low-carb is definitely a great way to go if fat loss is your goal. But as often is the case, things are never quite so simple. While discussing the six pack experiment with a friend of mine, he asked an interesting question:

Could it be that a low-carb diet works simply because you are restricting what you eat and eating fewer calories as a result? 

Put another way, if during my six pack experiment I made sure to eat the same amount of calories as I did before I went low-carb, would I still have burned so much fat? Unfortunately, I didn’t reliably track my daily nutrition data until one month into my six pack experiment, so I have no idea what my calorie levels were prior to going low-carb. It may very well be the case that, even though I made it a point to always eat until full while on my low-carb diet, the total calories I ate could still have been significantly less than before. 

Based on my experience thus far, I do believe that training your body to burn fat is a lot more complicated that just reducing your calorie intake. But how large of a role do calories play? By reducing consumption of foods that tend to contribute the majority of calories in a conventional diet (e.g. bread, pasta, rice, potatoes), you naturally create a large calorie deficit that must be filled with calories from either fat or protein in order to keep calorie levels consistent with life prior to low-carb. Filling this carb deficit is not particularly easy, so I wouldn’t be surprised if many low-carb dieters are indeed consuming fewer total calories in addition to eating fewer carbs. 

Thus in my next experiment, I want to explore the relationship between low-carb dieting and calories. I also want to explore the validity of conventional calorie math that suggests you should simply eat fewer calories and spend hours on the treadmill if you want to lose weight. A fact often cited is that a pound of human body fat equates to roughly 3,500 calories. Therefore, if you want to burn off one pound of fat, all you need to do is create a calorie deficit in your diet of 500 calories per day for one week. On the flip side, if you maintain a 500 calorie per day surplus, you can expect to gain one pound per week. General acceptance of this oversimplified calorie math is the reason why so many people believe that starvation and excessive exercise is the route to fat loss. But is it the best route?  

Experiment Design

Trying to lose weight due to a calorie deficit doesn’t provide for a very interesting, nor pleasant, experiment. If you maintain a significant calorie deficit, you are indeed likely to lose weight but how much weight and what percentage is from fat loss depends on a lot of factors.  

For this experiment, I will instead try to gain weight by maintaining a large calorie surplus while eating a low-carb diet and keeping "exercise" to a minimum.  

Here is the plan for the experiment:

  • Duration: 1 month
  • Calories: Daily average surplus of 1,000 calories 
  • Calorie breakdown: 60-70% fat, 20-30% protein, <=10% carbohydrate (except on Saturday cheat days)
  • Exercise: zero cardio and only 10-15 minute sessions of body weight exercises 2-3 times per week   
  • Key metrics: body weight, body fat %, measurements for biceps, thighs, chest, waist 

And that’s it for now! I'm going on vacation to Jeju Island this week so I’ll start the experiment after I return. Stay tuned! 

Update May 7, 2014 - EXPERIMENT POSTPONED

This experiment has been postponed! After I returned from my vacation this week, I went to get a blood test to see where I currently stand prior to embarking on this over-eating experiment. In particular, I wanted to see how my cholesterol levels have changed since going low-carb, high-fat. Unfortunately, my cholesterol levels have shot through the roof! Looks like I should learn more about cholesterol before I continue eating unlimited amounts of butter and bacon! I’ll provide more details in my next post.