Carbohydrates are the body's main source of energy. Carbs provide the fuel your body needs to perform everyday tasks such as digesting food, physical activity and keeping the all of the organs powered up. Without carbs, your body will underperform in a wide variety of tasks. Though low carb diets have attempted to link a decreased carbohydrate intake with increased weight loss, calorie reduction, not carb elimination is responsible.
Carbohydrates provide the body with its most efficient type of energy. They provide the body with 4 calories per gram. While fats and protein can also be used to fuel your body, you will perform better with an adequate amount of carbs in your diet. Your body needs energy for everything from digesting food to working out and simply staying alive.
All carbohydrates are made up of a varying amount sugar molecules. Carbs are classified based on how many sugar molecules are linked together to form a carbohydrate. When a few sugar molecules are linked together, the carbohydrate is called simple. When hundreds or thousands of sugar molecules are linked together, the carbohydrate is called complex.
Types of Carbohydrates
The two main types of carbohydrates are simple and complex. Simple carbs are made up of only a few sugar molecules while complex carbs are made up of hundreds or even thousands. The implication of simple vs. complex carbs is important to your overall health.
Good vs. Bad Carbohydrates
Carbohydrates are not all the same. Simple and complex carbs have different effects on the body. Simple carbs are digested and absorbed very quickly. They give your body a huge amount of energy in a very short period of time. If this energy isn't burned off quickly, it will likely get stored as fat. Complex carbs are digested and absorbed a lot slower. They give your body a much more manageable amount of energy over a longer period of time. This allows your body to burn the energy off without storing much of it as fat.
The different types of carbohydrates can also have an impact on your overall calorie intake. Since simple carbs move through your digestive system quickly, they will leave you feeling hungry a lot sooner than complex carbs. If you're trying to lose weight, your goal is to keep your calorie intake low. Eating simple carbs will leave you hungry which will lead you to eat more and increase your calorie intake. Complex carbs move through your system slower. Eating 300 calories of complex carbs will keep you full for a lot longer than eating 300 calories worth of simple carbs. Neither type should be completely eliminated from your diet, however your timing of both is important.
Timing of Carbohydrate Intake
Because simple carbs are digested and absorbed quickly, their intake should be limited to before, during and immediately following exercise. Your body's energy energy needs are very high before and during a workout. Simple carbs can be absorbed very quickly and give your body the fuel it needs for exercise. Immediately following exercise, your body has two main priorities: restoring energy levels, starting the recovery process.
Exercise will decrease your stored energy levels. Your body's main priority is to return them to normal levels. Carbs are stored as glycogen mainly in the liver and the muscle. Eating simple carbs (sugar) after a workout will help your body replenish those energy stores quickly allowing it to move onto its next priority, starting the recovery process. The recovery process fixes damage caused to muscle tissue during exercise. The recovery process is mainly facilitated by post workout protein intake. If you only provide your body with protein after a workout, that protein will be diverted from recovery and converted into sugar to replenish energy stores rather than fixing damaged muscle. A post workout shake should have a mix of simple carbs and protein.
With the exception of before, during and after exercise, your intake of simple carbs should be limited. Complex carbs should account for the rest of your daily carbohydrate intake. Because complex carbs are digested slowly, they won't give your body a huge influx of energy in a short period of time. This helps keep your body fat percentage low.
Sources of Carbohydrates
Simple carbs are found in foods high in sugar. These foods should be limited except during periods of exercise. Sources include: soda, fruit juices, sport drinks (Gatorade, Powerade), cookies, muffins, refined flour (white bread), doughnuts and candy.
Complex carbs are found in fruits, vegetables and foods made of whole grains including: brown rice, 100% whole grain flour (bread/pasta), beans and legumes.
Amount of Carbohydrates
Carbohydrates should account for 50-60% of your overall daily intake. Here is an example:
- daily calorie intake: 2,500 calories
- carb intake: 1,250-1,500 calories should come from carbs
- 312-375 grams of carbohydrates per day
The Bottom Line
Low carb diets have tied a decreased intake of carbs with decreased weight. Proponents of low carb diets attribute the weight loss to a cut in carbohydrate intake. Low carb diets work for the same reason that any diet works: a decreased calorie intake. When you create a calorie deficit, your body is forced to find the difference between what you burn and what you eat from sources other than food, either body fat or muscle which causes weight loss. Cutting all carbs out of your diet will create a large calorie deficit which will result in weight loss. You will get the same results by cutting overall calories rather than focusing on one macronutrient. Cutting carbs out of your diet will leave you weak and unable to perform at optimal levels.