Understanding the Hidden Link Between Blood Sugar and Mood

Can a Bag of Chips Cause Depression?

Has anyone ever told you that a potato chip could cause depression?

Okay, to be fair, probably not. And no, a single chip can’t do that. A bag here and there won’t either. But what if you’re eating a bag of chips every day? Or if you start your morning with a sweetened coffee and a croissant, grab a club sandwich and chips at lunch, and finish off with a burger, fries, and a soda for dinner? What if you eat like this for years—like most Americans do?

Now the link becomes clearer.

The hidden culprit here is blood sugar dysregulation. It might sound like a niche concern, or fad, but it’s not. Glycemic imbalance affects energy, weight, cognition, and yes, your mood. This article explores how blood sugar swings affect emotional well-being, why it matters for everyone (not just those with diabetes), and what you can do about it.

Let’s start with carbs, the main players in the blood sugar story.

Carbohydrates are our glucose-rich friends: sugar, milk, honey, rice, pasta, wheat, beans, potatoes, fruits, and grains like quinoa and spelt. In the Standard American Diet (SAD), we tend to favor the most processed versions—refined wheat, sugar, and potatoes.

When we eat carbs, the body converts them into glucose, its preferred fuel. Glucose powers your cells by being converted into ATP (adenosine triphosphate). Any excess is stored as fat or glycogen in the liver and muscles.

Not all carbs are created equal though. Some are slowly digested and give a gentle, steady supply of energy. Others hit fast, and drop fast too. When this occurs, glucose floods the bloodstream and triggers a hormonal cascade. That’s where glycemic index (GI) and glycemic load (GL) come in.

Glycemic Index and Glycemic Load: A Quick Primer

The glycemic index ranks carbohydrates on how quickly they raise blood sugar. Pure glucose is given a score of 100. High-GI foods (like white bread, cornflakes, and sugary drinks) break down quickly and send glucose surging into your system. Low-GI foods (like lentils, oats, or most fruits) digest more slowly, keeping things steady.

“Glycemic load adjusts glycemic index for portion size and total carbohydrate content, offering a more accurate reflection of a food's actual impact on blood sugar. A food may have a high GI, but if the carbohydrate content per serving is low, the GL can still be moderate or low. For example, watermelon has a high GI but a low GL, because most of its weight is water and the actual carbohydrate content per serving is relatively small. Therefore, the amount of glucose and fructose consumed is not significant.

● High GI, high GL: white rice, white bread, sugary cereals

● Moderate GI, moderate GL: brown rice, sweet potatoes, bananas

● Low GI, low GL: lentils, chickpeas, quinoa, non-starchy vegetables

Another important factor to consider is the quality of the carbohydrate. Refined grains—like those in white bread or crackers—have been stripped of fiber, nutrients, and much of their complexity. As a result, they break down faster and raise blood sugar more sharply than their whole-grain counterparts, like intact oats, brown rice, or farro. Whole grains come with their original fiber, fat, vitamin, mineral, and protein matrix intact, which slows digestion and creates a steadier rise in blood glucose.

What happens when high-GI foods hit your system?

Your pancreas releases a surge of insulin. You can think of insulin as glucose’s best friend. Glucose shows up at the cell’s doorstep and says, “Hey, I want to hang out.” Insulin opens the door. Glucose enters and the party begins. It is either used immediately for energy, stored as glycogen, or converted to fat if it exceeds immediate energy demands.

But then glucose levels crash. Cue the cravings for more sugar, more bread, more fuel. Glucose is kind of the life of the party so your body calls out for it in various ways when low. Cortisol, the stress hormone, steps in. As a glucocorticoid, cortisol tries to boost available energy in the body, drawing from glucose, stored fats, and even muscle proteins. Over time, this can lead to both fat gain and muscle loss. You’re breaking down your tissues for fuel and suffering from the numerous side effects of cortisol dysregulation simultaneously. We can explore this hormone in more depth in other articles.

The result is a metabolic rollercoaster: a quick energy spike, followed by a crash, then a compensatory craving-driven surge. This repeated pattern—common in many modern diets—places enormous stress on your system and sets the stage for mood disturbances. I'm sure you can imagine how cortisol-infused cravings cycling throughout the day and night can spell disaster, both mentally and metabolically.

The Link Between Glucose Dysregulation and Mental Health

Research increasingly shows a connection between poor blood sugar regulation and mental health issues. Hypoglycemia (low blood sugar) can trigger anxiety, irritability, brain fog, and even depressive symptoms. High blood sugar, on the other hand, is associated with inflammation, oxidative stress, and mitochondrial dysfunction—all of which impact brain health and neurotransmitter function (Rucklidge et al., 2019; Kiecolt-Glaser et al., 2015).

In fact, mitochondrial dysfunction alone—when the body’s cellular powerhouses are running poorly—is enough to contribute to fatigue, low motivation, and mood swings (Morris et al., 2017).

If this pattern continues unchecked, insulin resistance can develop. The more sugar you eat, the more insulin your body releases to deal with it. Eventually, your cells stop responding. Now glucose hangs out in the bloodstream, damaging tissues and driving up inflammation. This prediabetic and diabetic state is linked with depression, anxiety, cognitive decline, and a host of physical issues: weight gain, high triglycerides, CVD risk, organ damage, poor circulation, and hormonal imbalance.

So What Can You Do?

Balancing blood sugar is one of the single most important things you can do for your health, your mood, and overall wellbeing. It's one of the fastest and easiest ways to regulate erratic temperaments and stubborn weight gain. While for some, a ketogenic diet can be incredibly helpful, for the majority, carbs can stay. It just means choosing the right ones—and pairing them smartly. A nutrient-dense diet full of complex carbs (like sweet potatoes, oats, lentils), healthy fats (like avocado, nuts, and olive oil), and high-quality proteins (such as eggs and legumes) can create a much more stable internal environment.

Think fiber-rich meals, slower digestion, longer-lasting energy. Fewer cravings. More focus. Better sleep. Improved mood.

How We Can Help at Seed to Fruit

If you suspect blood sugar is playing a role in your fatigue, brain fog, or mood swings, we can help identify and address the root causes. We offer:

● Specialty lab testing: glucose, insulin, and hemoglobin A1c

● Continuous Glucose Monitoring (CGM): to assess real-time blood sugar fluctuations

● Functional testing: including food sensitivities, GI and stool testing, and microbial support

● Personalized nutrition: based on your unique biochemistry and health history

● Comprehensive care: addressing sleep, movement, stress reduction, and targeted supplementation

If you’re ready to stabilize your energy, elevate your mood, and optimize your metabolism, reach out for a complimentary consultation at seedtofruit.health.

References:

● Rucklidge, J. J., & Kaplan, B. J. (2019). Nutrition and mental health. The Lancet Psychiatry, 6(3), 192–194.

● Kiecolt-Glaser, J. K., et al. (2015). Inflammation: Depression fans the flames and feasts on the heat. American Journal of Psychiatry, 172(11), 1075–1091.

● Morris, G., et al. (2017). The role of mitochondria in mood disorders: From physiology to pathophysiology and beyond. Neuroscience & Biobehavioral Reviews, 72, 68–84.