Can Drinking Too Much Soda Make You Sluggish

How does drinking soda affect you?

Drinking soda and its negative effects

Drinking a soda is purported to increase one’s overall energy and productivity. If this is true, then why do people complain of sluggishness and fatigue after consuming soda?

Back in 1942, people in the United States were drinking roughly ninety eight-ounce carbonated, sugar-filled beverages each year. The American Medical Association, worried about the effects of large amounts of sugar on the human body, recommended that soft drinks be limited. Instead, by 2000, more than six hundred servings of soft drinks were being consumed on average per person per year in the US. This number has risen due to the initial energy boost derived from drinking soda, the low price, and the easy availability of sodas in today’s market.

The energy boost gained from drinking sodas is due to two things — caffeine, sugar, or both. Both are certainly capable of boosting mental alertness and focus. However, both are also able to cause irritability, fatigue, and sluggishness.

Caffeine, while able to alleviate mental fog and increase energy, negatively affects sleep by preventing deep sleep. An inability to fall into a deep sleep causes constant fatigue. Caffeine also causes dehydration, which also causes fatigue. Sugar, the main focus of this article, works a bit differently. Most foods convert in the body into glucose, a form of sugar, which the brain uses to stay functional and alert. Glucose provides staying power. Without glucose, it is difficult to concentrate and easy to become physically tired.

Sugar provides the body with a burst of immediate energy. However, the source of glucose makes a considerable difference as to whether that energy sticks around or not. While some foods, such as dairy, meats, oils, and whole-grain pasta and cereal raise and lower blood sugar levels more slowly, refined sugar, as found in sodas, has no staying power.

Refined sugar causes an immediate spike in blood sugar levels that tends to dip back down rather quickly, causing energy and alertness bottom out. Sudden spikes and drops in glucose are bad for productivity and even worse for the brain and body. It is this very condition that causes metabolic resistance and diabetes.

At this point, instead of reaching for a healthy snack, it can be tempting to reach for another soda. After all, it is challenging to think clearly and make wise decisions when one has no energy, is feeling irritable, confused, or sleepy. Reaching for another sugary beverage only serves to continue the negative cycle of having either very high or very low energy levels throughout the day.

So, can drinking sodas make people sluggish? Absolutely. But wait. What about sugar-free sodas? Are they not a better choice than regular sodas? No. Diet sodas can trigger an insulin response in the body, which causes one to. Remember, high spikes in blood sugar can provide a quick boost of energy, but that energy is short-lived, and then irritability and fatigue set in. Diet sodas may also contain caffeine, which is a diuretic and causes dehydration. Dehydration causes fatigue, headache, brain fog, confusion, irritability, and jitters, all of which reduce mental alertness and productivity.

Additionally, imitation sweeteners, such as saccharin and aspartame, release excitotoxins, which are chemicals that overstimulate brain receptors and cause the brain to become exhausted. It can also cause cravings for sweets, which is a likely reason for so many people regularly drink sodas.

A better solution for increasing energy, mental alertness, and productivity might be to eat regular meals and grab a handful of nuts, pieces of dried fruit, or a protein bar to tap into real staying power and avoid sluggishness.


National Center for Biotechnology Information,

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Soda Drink [ID 139467605 © Igor Marusitsenko |]