Carbohydrates are widely sourced in fruits and vegetables, grains, nuts and seeds, dairy, sweets, soda, the list goes on. It’s a good thing too because carbohydrates provide around half of the energy in a well balanced diet, 45-65% of calories.
After eating, carbohydrates are separated from dietary fibre and broken down into three monosaccharides: glucose, fructose and galactose. These monosaccharides are absorbed in the small intestine and enter the the blood stream.
Glucose is transported through the blood stream and is either:
- Immediately taken up by cells and turned into energy
- Stored as glycogen by the liver and skeletal muscles (Glycogen in muscles is turned back into glucose for energy during exercise and liver glycogen is what maintains our blood glucose levels during short fasting periods, like while we sleep.)
- Converted into fatty acids and triglycerides for long-term energy storage (if consumed in excess)
Carbohydrates serve an important role in your body including:
- They supply energy to the brain.
- They supply readily available muscle energy.
- They prevent breakdown of muscle tissue as an energy source, especially post-training.
- Fibre-rich carbs facilitate the digestive process and help prevent digestive disorders, such as constipation or diverticulitis.
- Fibre-rich carbs like whole grains, oats, and bananas grains take longer to digest, thus minimising your risk of overeating and becoming a calorie hoarder.
Some carbohydrates are more nutritionally dense than others; different types are digested at different rates and have different impacts on our blood sugar.
Theses are largely found in whole grains, starchy vegetables, legumes, nuts and seeds. They contain longer, more complex chains of sugars and generally also contain some fibre, protein and/or healthy fats, as well as important vitamins and minerals. The presence of fibre, protein and fats slows digestion and therefore absorption of those monosaccharides, resulting in a more gradual insulin response as well as increased satiety.
These come from healthy foods like fruits, vegetables and low-fat dairy, but also less nutritionally-dense foods like refined grains (white bread, white rice and traditional pasta), processed snacks and crackers, sweets and sugar-sweetened beverages like sodas. These foods contain sugars that are very quickly digested and absorbed into the bloodstream. Fruits, vegetables and dairy offer benefits such as vitamins, minerals, antioxidants, fibre and water, which is why they’re so good for you.
Refined grains, sweets and sodas are lacking all of these extra nutrients, which is why we should limit these foods in our diet. If your diet consists of high levels of refined sugars, more insulin is released and less of your stored fat is burned. High insulin levels also suppress glucagon and growth hormone. Glucagon promotes the burning of fat and sugar. Growth hormone is necessary for new muscle growth and development. Bad carb intake has no nutritional benefit whatsoever, bar the temporary dopamine release and happy chocolate dancing. Excessive amounts of insulin will push dietary carbohydrate intake to the adipose fat storage sites for future needs. Therefore, over consuming them leads to body fat accumulation.
Nutrient-dense sources are the healthier choice. These include complex carbs like 100% whole grain breads and pasta, brown rice, starchy vegetables, legumes, nuts, seeds, low-fat dairy and plenty of fruits and vegetables.
I hope that helps and makes you consider your food choices the next time that you pick up a muffin! They have their place for sure and we need to enjoy food and eat refined food from time to time, but if you want to ride better, look better and FEEL better then 9/10 the muffin can wait!