Monday Myths

Monday Myths – Are Carbs Really Always the Enemy?

Carbs continue to be the source of great controversy - find out here what works for you.

Carbohydrates and their role in a healthy diet is one of the most heated nutritional debate. Although low-carb diet may help to lose weight, reducing carbs too much is not appropriate for everyone. Find out if it is right for you.

Carbohydrates continue to be the source of great controversy. From the mid-1950’s to the 2000’s, they were the heroes. The Atkins diet revolution of the late 1990s, however, turned carbs into dietary villains. “Carbs make you fat” has been instilled into the minds of weight-conscious people. The advocates are attacking bread, pasta, and potatoes as the roof of evil. But are carbohydrates really a satan’s food?

To make things clear from the start, low-carb diets can help people lose weight. However, it is not an appropriate diet for everyone. If you’re someone who likes to exercise and who works out regularly, eating a low-carb diet for a significant length of time may hurt you more than it helps.


Bread makes you fat?

First of all, it is important to understand that carbs are not created equal and you cannot simply lump all carbs together into one category. After all, it’s hard to call all carbs bad when vegetables and fruits are carbohydrates.

There is much discussion about “good” and “bad” carbohydrates. There are two different types of carbohydrates you should know about. Carbohydrates can be either simple (“bad”) or complex (“good”).  Simple carbs include candy bars, soda, and baked goods. These carbohydrates are composed of single sugars which are broken down, digested and absorbed very quickly by the body. This kind of food create a surge in blood sugar and wreaks havoc on energy levels. They also contain little or no fiber.

In comparison,  complex carbohydrates contain longer chains of sugar molecules. These take more time for the body to break down and thus provide you with more sustained energy.  This also makes them more filling, and therefore a good option for weight loss. They are high in fiber and include foods like whole grains, legumes, fruits, nuts, and vegetables.


There is a lot of misinformation about low-carb diets. A very common argument used by low-carb advocates is that carbs spike your blood sugar and insulin, which slathers on the body as fat. It is true that carbs increase insulin levels. To say that increased insulin leads to fat gain is not true. Insulin is often-misunderstood. In fact, insulin is a satiety hormone. It makes you feel full therefore the argument that insulin, on its own, makes you fat does not follow.

Another common belief is that carbohydrates are not essential for our diets like fat and protein. Reducing carb-intake as a weight loss strategy works, as proven by the popularity of the Atkins diet. However, for the long term, most people require some level of carbohydrates to function at their best. This is especially true for physically active people.

For those who are sedentary, carb requirements are lower but for the active, drastically restricting carbs can lead to serious negative consequences. These include a slower metabolism, increase in stress hormones and decrease in muscle building hormones. All of these are explained in greater detail below.


In order to maintain an appropriate and properly functioning metabolism, your body produces an important hormone called T3. T3 is the most active thyroid hormone that plays an important role in the metabolic function and blood glucose management.

A landmark study, known as the Vermont Study, found that T3 is very sensitive to calorie and carbohydrate intake. It shows that when calories and carbs are too low, your T3 levels drop. Other studies confirm these findings, showing that ketogenic (ultra-low carb) diets can significantly reduce T3 levels. Furthermore, it causes reverse T3 to go up. Reverse T3 is an inactive form of T3 that blocks the cell receptors for thyroid hormones, thus blocking the effect of T3.

So when you don’t eat enough carbs while training:

  1. T3 goes down
  2. Reverse T3 goes up, blocking T3
  3. You will feel weak, experience fatigue, muscle cramps and frequent muscle aches. In other words, your training will suck

In essence, if you’re active, you need adequate energy and carb intake for a healthy thyroid.


Research consistently shows that people who exercise regularly need to eat enough carbs or their testosterone will fall while their cortisol levels rise. Extensive low carb diets can result in elevated cortisol and decreased testosterone production. This contributes to fat gain and muscle loss. Not what most of us want!


Building muscle is usually associated with protein consumption. However, research shows that low carb intake can negatively affect muscles even if protein remains constant.  So, no matter how many protein shakes you are drinking, if you’re not feeding your body enough carbs, you could be losing muscle. Without adequate carbohydrates, muscle glycogen is depleted and a catabolic (breaking-down) hormonal environment is created. This means there is more protein breakdown and less protein synthesis which translates to slower muscle growth and at times even muscle loss.

To put everything together, not eating enough carbohydrates can:

  1. Lower T3 levels
  2. Disrupt cortisol to testosterone ratios
  3. Contribute to muscle loss

So unless you’re a couch potato, a low-carb diet could be depriving you of energy needed for training.



There are merits in low-carb diets and they can be beneficial for primarily sedentary people. This does not hold true for active people and athletes, however. A high-intensity workout is impossible without adequate carbohydrates. Fat simply cannot supply energy fast enough to support maximum performance. Diets low in carbohydrates can cause muscle weakness and tiredness, making physical activity less enjoyable.

Essentially, carbohydrates are not evil. They are necessary to supply your body with the energy you need for your workout.


Interested to read more on this?

In this article, we explain the reasons for post-breakfast hunger. Ever feel hungry though you just ate breakfast??

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Wiktoria Banda

Wiktoria is a content writer and illustrator at Shape.
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