The Pros and Cons of Low Carbohydrate Diets


Fat has pretty much been figured out; a little bit is good for you and a lot of it is bad for everyone. Carbohydrates, however, are another matter altogether, and a matter under some pretty hot debate and extreme scrutiny in many fitness and wellness circles. Are carbs good? Are carbs bad? Are carbs good some of the time and bad at other times? This article will hopefully give you some clarity on this controversial topic.

Many people have cut out carbohydrates from their diet, and for a variety of reasons, mostly related to fat loss. There are also those who cycle their carbs, only having moderate to high amounts of carbs on workout days. Lastly, there are the ketogenic dieters. The ketogenic diet is a nutritional program where you cut out basically all carbohydrates. The ideology is that once you cut out carbs, fats are replaced as your main energy source, which helps you lose body fat and stay lean.

In this article, we’re going to take an in-depth look at low-carb diets. We will find out what makes them tick, and how they can give us an advantage, or a disadvantage, in terms of reaching our fitness goals.

Muscle Gain
Diets low in carbohydrates are typically not optimal for building muscle. It isn’t just a problem with the energy source, it’s due to the glycogen stores in your muscles. Glycogen is the storage form of carbohydrates found in your muscles. This substance primes your muscles for movement and gives you that explosive power you need to complete your lifts, as well as to help spark the recovery process by inhibiting the breakdown of proteins in your body. When your muscles have a limited storage of glycogen, they have less energy and less ability to stop protein breakdown. Intra-workout and post-workout carbohydrates also perform the task of producing growth hormone which is the hormone that regulates muscle growth. Obviously, if you’re taking away the agent which causes muscle growth, you will be limited in the amount of growth you can achieve.

There are several low-carb and ketogenic dieters that claim that fat is an adequate energy source for building muscle, but there is no actual data to back that up. Fat isn’t stored in the muscles as an energy reserve in the way that carbohydrates are, and your body won’t be able to make use of it the same way. Will fat as an energy reserve get you through the day, along with a few circuits and sprints? Sure, it will. Will it get you through a bodybuilding-style high intensity workout and prime your body for growth as your body recovers? No way!

Fat Loss
Fat loss is where low-carb diets truly shine. The main reason is that high-carb foods are calorically dense, and switching to a low-carb diet means that you’re first and foremost ingesting fewer calories. Thanks to the law of thermodynamics, fewer calories always equates to weight loss. Foods like pasta, bread, pastries and bagels are easy to make and several of those items are very convenient, grab-and-go foods you can get at corner stores or Starbucks to get you through your morning meetings. This perpetual snacking and on-the-go dieting that many people follow is one of the biggest contributors to fat gain and the difficulty in losing it. Consumed in moderation, all of these snack foods are fine, but when you start to go overboard, the weight will start piling on. Keeping weight off is a lot easier than losing weight. One of the major stigmas of carbohydrates are due to the fact that, when consumed in excess, they will be stored as fat; therefore, in the eyes of many fitness buffs, carbohydrates equal fat. Lowering your intake of carbohydrates is not only healthy, but it is one of the quickest and most dependable ways to cut calories and lose weight.

The Ketogenic Diet
As we previously touched on, the ketogenic diet is the diet in which you cut out almost all of the carbohydrates from your macronutrient intake. The philosophy behind this is pretty interesting. When your body runs out of carbohydrates, it starts running on fat and producing what are called “ketones”. Ketones are produced by the body as an energy source in reaction to a low concentration of carbohydrates. This happens not only during a ketogenic diet, but during periods of prolonged intense exercise and starvation. Basically, a ketogenic diet puts your body in emergency mode and keeps it there, which is why it is an effective way to lose weight.

However, maybe your primary goal in the gym isn’t to lose weight, or maybe you want to lose fat, but also pack on a bit of muscle mass. With the ketogenic diet, gaining muscle is pretty difficult. Extreme limiting of your carbohydrate levels not only negatively impacts your energy levels, but it also cuts down your muscle glycogen levels. Decreased glycogen means your muscles have less energy to perform intense exercise, and less potential to produce growth hormone to spark an increase in size.

Carb Cycling
How can you have the benefits of both and follow a low-carb diet that can still help you pack on some muscle? That is where carb-cycling gracefully steps in. The ideology behind carb-cycling is that during times of low activity, you keep your carbohydrate intake low to keep your body in fat-loss mode. However, pre, intra and post-workout, you’ll spike your carbohydrate intake so that your muscle glycogen levels shoot up and your body will produce that glorious growth hormone so that you can pack on some new muscle tissue.

Carb-cycling has been proven very effective for bodybuilders who want to stay lean, or even shed some body fat while staying on track with their mass gain program. This option can also be great for people strictly looking to lose weight that don’t want to go as extreme as the ketogenic diet, since switching your energy source from carbs to fats is a difficult process that comes with cravings and mood swings. One of the main reasons that a diet fails for anyone is that the diet isn’t adhered to for the long-term. If having a few carbs here and there helps you stick to your diet, then going hardcore with the ketogenic diet just to cheat is much less effective.

Final Thoughts
Although we summed up some key points here, there is still some pretty serious division on the topic of carbohydrates in the weight loss and bodybuilding communities. Is it high-carbs for lots of muscle, or is it ketogenic as a cure-all? There are several benefits and drawbacks to most ideologies when dealing with carbohydrate intake. Do you have your spaghetti and meatballs post-workout, or do you stick to chicken and broccoli? Choosing your meals is extremely important in your journey to your ultimate fitness and physique goals. Once you develop an ideology, it’s crucial to identify the foods that can help you reach your goals and make a grocery list to solidify your new diet and make your plan more attainable. Do your own research and keep some of the points we discussed in mind, and you’ll be well on your way to a diet that you can not only stick to, but thrive with!

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About Author

My name is Cole Matthews and I'm a certified personal trainer who's a major health and fitness geek with a huge passion for writing. See my profile page for more information!


  1. Great article, Cole! I agree, there’s no one simple answer and always the Principle of Individual Differences as well. For me, I’ve found that simply cycling seems to work best. If I’m too low on carbs, I’ll feel weak and performance suffers; however, when I’m leaning out and not as concerned with growth then I’ll cut back pretty significantly but not all carbs. That said, I’ll keep “excess carbs” or processed stuff to a bear minimum most year around and choose whole food carbs first. All in all, I have great lifts and keep body fat levels in acceptable range for me. For me to go from 157 lbs to 200 lbs really took an awful lot of work and eating so it’s not just easy-peasy to keep my body fat percentages real low while also eating to maintain mass! But, I think you pretty much summed it up, we’ve all got to choose our path and figure out what diet type is going to get us the best results. Good luck, man!

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