How sugar shapes your cravings, mood, focus, and what you can do about it.

Ingesting sugar affects our brains and can trigger cravings. But the effect is broader: sugar influences our neural circuitry, impacting mood and attention. In short, sugar can inhibit you from achieving your goals.

Understanding what happens in the body when we eat can shed light on the effects of sugar. Let's explore the physiological responses involved.

When we haven't eaten in a while, a hormone called Ghrelin rises in our body, signaling hunger. Once we eat, Ghrelin levels drop. When we consume food, whether that's carbohydrates, fat, or protein, our blood glucose levels rise.

The body and brain don't function well when glucose levels are either too high or too low. To manage this, the pancreas releases a hormone called insulin to regulate the amount of glucose in the bloodstream. It's worth noting that neurons in the brain run off of glucose, but this does not mean you should eat an excess of sugar to think more clearly.

Sugar cravings: why they're so powerful

Many parts of the body require glucose to function, so we have specialized brain systems dedicated to seeking sugar. Two main pathways drive this behavior:

PATHWAY 1: Taste & Perception

One part of this pathway concerns the actual taste of sugar; another concerns our perception of that taste. This pathway affects all living things and drives the universal desire to seek out sugar. 

PATHWAY 2: Nutritive Component

This pathway is determined by the degree to which a food raises blood glucose. Foods that raise blood glucose are typically associated with that sweet taste, reinforcing the drive to consume them.

These sweet pathways are specific to sugar; they are distinct from those associated with salty or savory foods, and they are hardwired into all living mammals.

Key Takeaway: When you crave something sweet, like cake or candy, your neurons want both the taste and the nutritional value. It’s a two-fold drive.

How sugar changes your perception

Our entire mouth and tongue are lined with sweet receptors. When we eat something sweet, those receptors send signals to the brain, causing us to seek out the source of that sweetness and changing how we perceive the world around us.

Case study: Participants who drank a sugary beverage and then viewed images of food reported that the foods appeared more appetizing, including those that contained no sugar. The takeaway: when you eat a sugary food, your brain immediately shifts your perception so that you seek out more sugary food, and food in general.

Dopamine: the craving engine

Dopamine governs our reward system and drives us to pursue rewards. Ingesting sweet foods stimulates the dopamine pathway, which signals a drive to pursue more sweet things. Triggering this pathway produces a sensation of wanting more, which is precisely what we call a craving.

When someone says they need their "sugar fix" and satisfies it with something sweet, that act triggers the dopamine reward system, reinforcing a new, often counterproductive habit of treating cravings with more sugar.

Self-test: the pleasure-pain balance. While eating something sweet, like a piece of chocolate, notice how you feel and savor the experience. Then, as you reach the last bite, pay attention to what happens in your mouth afterward. You'll likely notice your taste buds wanting more, perhaps even salivation, that subtle "pain" of wanting another hit of the pleasure you just experienced. This is the dopamine loop in action.

Tools: curbing sugar cravings

Understanding the mechanisms behind sugar cravings opens the door to managing them. Below are evidence-informed strategies worth exploring.

Pair high-glycemic foods with fiber: Different foods have different glycemic indexes, which measure how quickly they raise blood sugar. When you pair a high-glycemic food with fiber, the fiber slows the absorption of sugar into the bloodstream and lowers the resulting glucose surge. For example, if you want to eat a high-glycemic fruit like a banana or a mango, pair it with plain unsweetened Greek yogurt or a plain unsweetened rice cake. This combination reduces the speed and height of your sugar spike, lessening the dopamine-triggered craving for more sugar.

Omega-3 fatty acids: Supplementing your diet with fish oil or another source of omega-3 fatty acids has been shown to help reduce sugar cravings. Omega-3s may support brain health and help regulate pathways involved in reward responses, thereby reducing the urge for sugary foods.

Glutamine : High sugar intake can disrupt the gut and contribute to leaky gut. Glutamine, an amino acid related to gut health, has been shown to help heal leaky gut. Some people notice that when their gut health improves with glutamine, their sugar cravings decrease. During cravings, some use glutamine combined with full-fat cream. Increase glutamine slowly to avoid stomach discomfort. Research on this topic is ongoing.

Lemon or lime juice: Consuming lemon or lime juice before, during, or after eating a high-glycemic food may lower the resulting glucose spike. This effect may happen because sour receptors on the tongue adjust the brain's response to sweet tastes, thereby blunting the urge for more sugar.

Cinnamon: Cinnamon can slow the rate at which glucose enters the bloodstream by delaying stomach emptying. This results in a lower glycemic index for the meal. Research suggests that any type of cinnamon can be helpful in this regard. 

Berberine (use with caution): Berberine is a substance derived from tree bark and is known as a potent agent for lowering blood sugar. It acts similarly to the prescription diabetes drug Metformin. Because berberine can sharply lower blood sugar, it may cause hypoglycemia—especially on an empty stomach or a low-carb diet. Only use berberine with meals that contain a substantial amount of carbohydrates to prevent unwanted drops in blood sugar.

Quality sleep: Research has shown that certain sleep stages support proper sugar metabolism. Skimping on sleep can increase cravings for sugar, likely because sleep deprivation throws off metabolic processes. Prioritizing regular, quality sleep helps keep cravings in check by supporting balanced appetite and stable sugar-related metabolism.

A note on artificial sweeteners

In a Pavlovian-style study, participants were given maltodextrin, a substance that increases blood glucose and insulin levels, hidden within a particular flavor. Over time, the maltodextrin was removed, but the flavor was maintained. Remarkably, subjects continued to experience blood glucose increases solely from that flavor, even without maltodextrin present.

This suggests that particular flavors become conditioned to patterns of blood glucose increases, and raises important questions about artificial sweeteners.

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For more information, feel free to reach out to Madeline at madelinerose.fitness@gmail.com or online at Madeline Rose Fitness

Madeline Jeffries is the host of our monthly Venbrook-sponsored Nutrition Navigator series every first Wednesday of the month at 12 pm PST.

Researcher Dana Small offers a simplified interpretation: "If people are going to ingest artificial sweeteners, and they do that along with foods that sharply increase blood glucose, there is the potential for those same artificial sweeteners to increase insulin, even in the absence of food." As a practical example, if someone habitually has a diet cola with a burger and fries every day, having the diet cola alone may eventually trigger a blood glucose and insulin response; the body has learned to associate that flavor with what follows. Note that studies involving plant-based sweeteners such as stevia or monk fruit have not yet been conducted in this specific context.