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Tired after eating carbs? Here’s why



Think about the last time you ate a plate of pasta, a large helping of mashed potatoes, or your favorite cake. You may have felt satisfaction initially from having enjoyed a delicious food, but chances are that satisfaction soon gave way to a drop in energy.


Why does this happen? The foods we eat have a bigger impact on our mood and energy levels than we might realize. Whether you’re feeling a short-lived energy surge or want nothing more than to take a quick nap after lunch, the food you just ate may be the culprit. If you find yourself feeling tired after eating carbs, this post is for you.


What carbs do for the body


Carbohydrates are one of the body’s primary sources of energy. When we eat carbs, the digestive system breaks them down into glucose, which is then absorbed into the bloodstream and used as fuel, or energy.


So, by this logic, carbohydrates should leave us feeling energized, not tired, right? Sadly, it’s more complicated than that. While you may experience an initial energy surge, your energy will drop just as suddenly as it rose, and soon you’ll find yourself putting all your remaining energy into staying focused and awake.


Glucose, insulin, and the brain


To understand why we’re tired after eating carbs, we need to delve into the intricate relationship between blood sugar (glucose) levels, insulin, and neurotransmitters in the brain.


Any time you consume a meal high in carbs, especially refined carbs found in white bread, pasta, and sugary snacks, your blood sugar levels will quickly rise. In response, the pancreas releases extra insulin, a hormone tasked with transporting glucose from the bloodstream into cells for energy (or storage, to be burned for fuel later). As insulin ushers glucose into the cells, blood sugar levels drop. This rapid decline in blood sugar combined with the larger insulin response is what triggers the dreaded post-meal fatigue, otherwise known as the “carb crash.”


This rapid rise and fall of blood sugar levels can also disrupt the balance of neurotransmitters in the brain, particularly serotonin and dopamine. Serotonin, often dubbed the “feel good” hormone, plays a crucial role in regulating mood, appetite, and sleep. Carbs promote the release of serotonin, which can initially make us feel relaxed and content, but the subsequent drop in blood sugar also leads to a decline in serotonin production, leaving us feeling irritable, anxious, or tired.


High-carb foods can also affect the production of another neurotransmitter, dopamine, which is involved in motivation, pleasure, and attention. Rapid fluctuations in blood sugar levels can dampen dopamine activity too, further contributing to the tiredness you feel after eating.


Not all carbs are created equal


Since carbs provide fuel to keep us energized, carbs are still an important part of a healthy diet. The trick is to get the right kinds of carbs, because some are definitely better than others.


Simple carbs. These are the carbs you want to avoid. Simple carbohydrates are found primarily in foods containing refined sugar and refined grains. This includes sugary drinks and snacks, baked goods, and white pasta. These foods are quickly digested and absorbed into the bloodstream, which is what causes the sharp rise and fall in blood sugar, leaving you feeling tired and hungry soon after.


Complex carbs. Foods with complex carbs include whole grains, legumes, whole fruits, and leafy greens. These foods have a lot of fiber, which slows down the absorption of glucose into the bloodstream, providing a more sustained release of energy and keeping you full for longer. These are the carbs you want to prioritize in your diet, as they provide the fuel you need for energy without leading to an energy crash later.


Learn more about the benefits of complex carbs in our Q&A with the Unicity science team.


How to eat without feeling tired afterward


Small adjustments can have a big effect on your energy levels and your overall health. If you find yourself feeling tired often after you eat carbs, these tips will help get you on the right track.


Focus on complex carbs. Instead of trying to cut out all carbs, get as many carbs from plant-based foods as you can. 


Pair simple carbs with protein, healthy fats, and fiber whenever possible. We get it; foods loaded with simple carbs can be too delicious to ignore at times. Eating a high-carb food with something that takes longer to digest (like fiber or protein) can help minimize the impact the carbs will have on your blood sugar levels, and by extension your energy levels.


Take short walks after meals. Regular exercise is one of the best non-diet things you can do to help keep the post-meal tiredness at bay. A short burst of exercise after a meal, like a walk around the block or kitchen clean-up, can slow the post-meal glucose spike.


Take Unicity Balance. Our best intentions can only get us so far—because life happens. Unicity Balance can help make up the difference, even if we don’t always make perfect choices for our health. 


Balance contains a fiber matrix that is designed to help ease some of the impact excess carbohydrates can have on the body and keep you feeling full for longer. A recent study found that those who drank Balance before their meals had a reduced glucose response compared to those who didn’t take Balance. So, taking Balance with your meals is an easy way to support normal, healthy blood sugar levels and help eliminate post-meal fatigue.


Avoid the post-meal slump with foods that energize


While carbohydrates are an essential source of energy for the body, large amounts of simple carbs can lead to fluctuations in blood sugar levels and neurotransmitter activity, ultimately leaving us tired and sluggish. A more balanced approach to diet, including complex carbohydrates, healthy fats, and lean protein—as well as taking Balance with your largest meals—can help us maintain steady energy levels and avoid the post-meal crash entirely.

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