Why do I fall asleep after eating carbs?

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If you find yourself falling asleep after mealtimes despite getting a full night's sleep the night before, you may need to take a look at the foods you eat and whether you have too many carbohydrates in your diet. They affect your energy levels and alertness.

A balanced diet of carbohydrates, proteins, fats, vitamins and minerals will keep you alert. Too many carbohydrates can cause you to fall asleep or feel sluggish after a quick burst of energy. This is called a sugar crash.

What Are Carbohydrates?

Carbohydrates are compounds that always contain some ratio of carbon, hydrogen and oxygen. The hydrogen and oxygen exist in a 2:1 ratio just as they do in water. Carbohydrates are partially responsible for the production of energy within the body. The simplest carbohydrate, glucose, is split into smaller molecules. The glucose also reacts with oxygen, and some of the hydrogen atoms bond with the oxygen atoms to produce water. The release of these bonds provides the body with energy.

Blood Sugar

When carbohydrates enter the body and are broken down into simpler sugars, they enter the bloodstream and cause the pancreas to secrete insulin, a compound that absorbs blood sugar and sends it to the cells. This causes the tissues to draw glucose rapidly from the blood, drastically lowering the blood sugar levels. When this happens, the body interprets the low blood sugar as a state of hunger, and you begin to feel lethargic, tired and irritable.

Simple and Complex Carbohydrates

Not all carbohydrates induce a severe sugar crash. There are two types of carbohydrates, simple and complex. Simple carbohydrates exist in short molecule chains that can break easily. They therefore digest quickly and transform into energy, causing blood sugar levels to rise more quickly and make a sugar crash likely to occur. Complex carbohydrates, on the other hand, take longer to digest, and therefore, the increase in glucose levels is more gradual. You should have more complex carbohydrates in your diet; they give you the energy you need without causing wild fluctuations in your blood sugar.

What Foods to Eat

Most processed foods are simple carbohydrates. The overcooking and processing causes the molecules of the food to break down rather than remain in complex chains. Your body needs complex carbohydrates for a safer source of energy. Whole wheat bread, brown rice, pasta, fresh fruit, milk and meat are considered complex carbohydrates because their molecules coexist with protein and fibre, making them more difficult to digest.