Why you shouldn't be afraid of carbs
Carbohydrates. What comes to mind when you hear that word? A big, glutenous loaf of sourdough bread? A heaping bowl of pasta? Mashed potatoes? More often than not, when we think of “cutting carbs” these are the foods that come to mind. But carbs don’t just live in starchy flour based foods – carbs are everywhere! In fruits, veggies, legumes and more. So why are we so obsessed with cutting them out? How did they become so demonized in the health and fitness industry? As is often the case, it began with a scientific hypothesis.
The Carbohydrate-Insulin Hypothesis
The carbohydrate-insulin hypothesis suggests that a diet heavy in carbohydrates (especially refined grains and sugars) leads to weight gain due to a specific mechanism: insulin. Carbs drive up insulin in the body, causing it to hold onto fat and suppress calorie burn. According to the hypothesis, to lose weight you have to reduce the amount of “carb calories” you eat and replace them with “fat calories”. This drives down insulin levels, boosts calorie burn and helps with fat loss.
Like any scientific hypothesis, it has to be put to the test. So what happened when researchers studied the effectiveness of low carb diets? Well, they found very little success. Based on the hypothesis, there should have been a significant acceleration in fat loss when insulin secretion was cut by 50%. But, a controlled eating study led by the National Institute of Health and obesity researcher Kevin Hall revealed that the though participants on the low carb diet did experience a short increase in calorie burn, it only amounts to about 100 extra calories per day.
Despite the increasing evidence, carb cutting diets are still skyrocketing in popularity. They go back as far as the late 1700’s but modern iterations of the low carb diet such as the Atkins diet and the Stone Age diet helped cement the idea that carbs are food enemy #1. Once these diets began to fall out of favor, they re-invented themselves as the “Keto” and “Paleo” diets.
What Are Carbs?
Carbohydrates are one of the three main building blocks that make up all food. The other two are protein and fat, and all three are essential for the body to function. Carbs are further split into 3 groups:
- Sugars: monosaccharides and disaccharides (Fruit, white sugar)
- Starch: polysaccharides (potatoes, pasta, grains, bread)
- Dietary fiber: polysaccharides (Legumes, whole grains, nuts and seeds.)
When we eat carbs, our gut breaks down the polysaccharides and disaccharides so that our gut can absorb the resulting monosaccharides. This causes our blood sugar to rise, stimulating the release of insulin which enables the cells to take up glucose and use it as an energy source. If your body is a car, carbs are the gas.
Your Body’s Preferred Energy Source
Carbs become glucose. Glucose is used by all our tissues and cells to get our body to function. Remember those other two building blocks? When your body can’t use carbs it turns to fat and protein, which are much harder to convert into energy.
Fat is not an efficient fuel source as it doesn't get digested fully. The ketones that are produced when the body is forced to use fat instead of carbs is slightly acidic. Over time this acidity can build up in the blood over time and cause damage to the body.
Protein is a building block, not an energy source. Using it for energy can compromise muscles and other cells.
Individuals on low carb diets can suffer from a lack of energy since their body is working overtime to try to produce energy from insufficient sources. Back to our car metaphor; trying to fuel your body with only fats and proteins is like trying to put diesel in a gas engine. It just doesn’t run the same and may cause it to break down.
Carbs Help Control Your Appetite and Cravings
When our insulin levels get low we are more likely to reach for sugary, processed food to satisfy our hunger. Complex carbs are digested much slower and help keep us satiated throughout the day. Foods like whole grains and legumes help us meet our daily fiber requirements which helps stabilize our blood sugar and less food cravings. Skipping out on carbs also means you‘ll miss out on key minerals and essential fatty acids. Research shows that high fibre diets can decrease the risk of diabetes and cardiovascular diseases.
The Bottom Line
Incorporating carbs into your diet is healthy and sustainable for weight management. Pay attention to your portions if your goal is weight loss or diabetes management, and choose complex carbohydrates as opposed to simple ones. Remember, eating some bread and pasta isn’t going to kill you or magically undo weight loss. It’s all about balance. Besides, life is too short not to eat foods you enjoy!