Round 10: Do Carbs Or Fats Make You Fat?

What will make you fat, carbs or fats?

JC: Calories make you fat. Now that I have put that out there – we can dig a little deeper. This question has the potential to become a book, so rather than lay it all out on the table, I’m going to take it one step at a time.

First and foremost, and this is what I tell those I work with, dietary fat does not make you fat. Carbs do not make you fat. The misuse of both however, has great potential to make you fat. It is a common misconception that fat makes you fat, and this is for two reason; 1. Fat is called Fat, and 2. Fat is more than twice as calorically dense than carbs or protein. One must keep in mind there are different kinds of fats, much like how there are different kinds of carbs. Monounsaturated fats, polyunsaturated fat, Omegas…Complex carbs, simple carbs/sugar…each has a role and if not properly incorporated into a diet you can find yourself in a bit of trouble.

To begin, one must be well versed on carbohydrates and how they work in the body. Knowledge of the glycemic index and the insulin response that accompanies the ingestion of food will help you better understand why one type of food has greater potential for weight gain over another. Since carbohydrates elicit an insulin response, you want to be sure that you are consuming good quality food when the insulin is released. Since the nutrients are going to be forced into the cell, consuming vast quantities of fat with your carbs will not be doing you a favor – especially if your fat is trans fat from unhealthy oils. Take a carnival funnel cake for example – crappy carbs, fried in crappy oil, topped with crappy sugar. Once you eat it your insulin is going to spike (from the carbs/sugar) to get your blood sugar down. All that junk (fat) that is coursing through your system is going to be forced into your cells. You won’t need it all and it is going to be stored for later…as fat.

So what made you fat, the carbs or the fat? Well, technically speaking, both…they worked together as they should, but in this case not in your favor.

Now, if you ate a whole avocado which is about 20g of fat and then a cup of brown rice which is about 60g carbs with a bit of fat and protein, would you achieve the same biological response. Not at all. Not only are the nutrients of a higher caliber, but the rate at which they are digested and absorbed is significantly different from that of the lower grade processed junk – allowing your body to process and distribute at a more reasonable and beneficial rate.

Matt: Let me first say that I 100 percent agree with every single thing JC said BUT (you knew that was coming, right?) I’d like to add my two cents anyway.

If you had two different macro splits, one leaning heavily to the carb side and one leaning heavily to the fat side, and both are exactly the same calorie totals, the diet that was higher in fat would allow for greater fat loss than the one that was higher in carbs and in turn the higher carb diet will be more likely to make you fatter.

Carbs are insulinogenic, fat is not. Due to this fact, carbs make fat burning difficult by raising insulin levels and also by providing the body’s preferred fuel source, glucose. You aren’t going to tap into fat stores with loads of glucose and insulin in your blood. If you replaced the majority of those carb calories with fats, you would keep insulin levels low and force the body to use it’s own fat for fuel due to the lack of glucose and in turn, glycogen available.

I’m not even talking deep ketosis (you know, that diet that I’m always telling you works even though it will kill you, if you believe everything that you read that is), I’m just talking about a good, low carb diet that is around 100 grams of carbs per day.

JC: I can’t disagree with that. When I prep for a show I work my way down to 100g carbs per day – there is no denying what works. I am of the same opinion though. A diet based solely on carbs has a greater potential for fat gain as opposed to a diet formulated around fat. But again, you can’t turn a blind eye to the facts.

1.   Calories in vs. calories out

2.   High GI vs. low GI.

3.   Metabolism.

I swear, there are times when I feel that my kids are running on nothing but chicken nuggets and chocolate. Hence the influence of number 3.

I’m treading on new ground here and am at the limit of my “expertise” – but I would be interested to see what happens when two similar subjects are tested on 2000 calorie diets, one based on carbs and the other on fat.

Colin: As much as I’m sure everyone would love an answer that says one or the other makes you fat, I think everyone also expects the answer to not be that cut and dry. I don’t think either one of them makes you fat. It’s not the marco that makes you gain fat, it’s the type of quality the macro is as well as how much of it is eaten. No matter what you eat, if you eat over your maintenance level of calories you are going to gain fat.

When it comes to fat the ones you want are the unsaturated fats, monounsaturated and polyunsaturated

fats. There is room for some saturated fat but the main one you want to avoid at all costs is trans fats. While the unsaturated fats have a good list of health benefits, trans fats clog arteries, increases LDL, decrease HDL and a host of other health problems.

When it comes to carbs, there is a huge difference between eating complex carbs and simple carbs high in sugar. The simple carbs produce a rapid increase in blood glucose levels which spikes insulin levels. The digestive system is pumping glucose into the bloodstream faster than insulin can move it into the liver and muscles so the body converts the excess glucose into fat to store for later “use.” The complex carbs are digested much slower and thus a slower glucose rise as well as insulin and fat storage. Not to mention complex carbs help you feel full while simple carbs do not, so you find yourself not only eating more, but eating more of the stuff that makes you fat.

The other thing that comes into play is how each individual responds to carbs. Some people can easily eat hundreds of carbs per day with no problem at all, while others may gain fat eating anything over 150 grams. It’s for that reason, if I had a gun to my head and had to pick between the two, I’d say carbs more so than fat. I don’t like that answer though, because as long as you are eating the right types of foods, it likely won’t matter.

Dara: I’m not going to reiterate what has already been said. Instead I’m going to simplify a bit by going back to the original question “what will MAKE you fat?” I think we’ve established the pros and cons of various fat/carbs ratios in terms of effective fat-loss diets, but that comes after you’ve already gotten fat, technically. When it comes to what will actually take you from lean to fat and cause you to fill your fat stores with adipose tissue. Keeping in mind that I agree with what has already been said, I’m going to answer from a behavioural rather than a physiological stance and say carbs make you fat. This is for a multitude of reasons but mostly because carbs are the quick and nutrition-less snack foods that we love the taste of and yet they just don’t satisfy so we eat way too much. As delicious as fat is, it does tend to satisfy and you can’t overeat it the same way you can carbs. Not to mention the carbs in alcohol. Quick and dirty carbs are cheap and easily available and taste so good that it’s easy to overeat your way to becoming fat very quickly. Just ask any college student living on ramen noodles, chips, and beer.

Michael: This is going to sound like a total copout, but I am just now learning how little I really know about the power of precise nutrition and the impact of macronutrients. I’m coming to understand that it’s more than what your total values are, but also when you consume them and from what sources… not just the sum totals.

So, I respectfully decline to give my “expert” opinion on this topic. It’s over my head!

Dara: I don’t feel it’s a copout at all. I have great respect for someone who is willing to admit where they are lacking knowledge and are making an effort to fill in the gaps, rather than trying to sound like they know what they are talking about. This industry is always changing and growing and if you find someone who claims to know everything about everything then I advise you to run far away from them! I find the more I learn the more I realize I need to learn, which is one of the reasons I love what I do!

Round 1: The best fat loss method

Round 2: Fasted vs fed cardio for fatloss

Round 3: Fat loss and muscle-building supplements

Round 4: Nutrient timing/meal frequency for fat loss/muscle-building

Round 5: The best 3 exercises

Round 6: The ideal training program

Round 7: How much protein for fat loss

Round 8: The last 10 pounds

Round 9: The ultimate training split

Happy Lifting!