Blood Sugar and Anxiety: What You Need to Know

Key Takeaways

• Blood sugar fluctuations can trigger symptoms that mimic or worsen anxiety, including shakiness, irritability, and poor concentration
• Rapid rises and drops in glucose can activate stress hormones such as cortisol and adrenaline
• Cravings, energy dips, and feeling “hangry” are often physiological responses to unstable blood sugar rather than lack of willpower
• Balanced meals that include protein, healthy fats, and fibre can help support more stable energy and mood
• Consistent eating patterns and simple nutrition strategies can reduce the cycle of anxiety, cravings, and energy crashes

If you experience anxiety, shakiness, irritability, or sudden drops in energy, did you know that your blood sugar levels may be playing a role?

While anxiety has many causes and can be influenced by psychological, environmental, and physiological factors, blood glucose regulation – or blood sugar balance - is one area that is often overlooked. Yet it could potentially have a big impact on how calm, focused, and emotionally balanced you feel throughout the day.

For many clients, symptoms such as anxiety, low mood, brain fog, and intense cravings are closely linked to how and when they eat.

How Blood Sugar Fluctuations Affect Anxiety

Blood sugar, or blood glucose, refers to the level of glucose circulating in the bloodstream. Glucose is the body’s primary source of energy, particularly for the brain.

After eating, blood sugar rises, triggering the release of insulin to help move glucose into cells. However, when meals are high in refined carbohydrates or lacking in protein and fat, this can lead to a rapid spike followed by a sharp drop in blood glucose.

These fluctuations can activate the body’s stress response.

When blood sugar drops too low, the body releases stress hormones such as adrenaline and cortisol to bring levels back up, as your body is concerned there won’t be enough fuel for the brain. This process can trigger symptoms that feel very similar to anxiety, including:

• Racing heart
• Feeling shaky or lightheaded
• Irritability or sudden mood changes
• Difficulty concentrating

Research has shown that maintaining more stable blood glucose levels is associated with improved mood and reduced feelings of anxiety.

If you would like a broader overview of how nutrition influences mental wellbeing, you can read my recent blog on the food–mood connection.

Common Signs of Blood Sugar Imbalance

Blood sugar imbalances are not always that obvious, and many people experience symptoms without immediately linking them to how they are eating.

Glucose is the brain’s primary fuel, so fluctuations in blood sugar can directly affect cognitive function, mood, and energy levels. When blood glucose rises and falls rapidly, this can lead to periods where the brain is temporarily under-fuelled, contributing to symptoms such as difficulty concentrating, low mood, and mental fatigue.

You may notice this as mid-morning or mid-afternoon energy dips, particularly if meals are high in refined carbohydrates or if there are long gaps between eating. Feeling irritable or “hangry” when meals are delayed is another common sign, as the body responds to falling glucose levels by activating the stress response.

Cravings, particularly for sugary or high-carbohydrate foods, can also be a physiological response rather than a lack of willpower. When blood sugar drops, the body seeks quick sources of glucose to restore balance, often driving a preference for foods that provide rapid energy.

For some individuals, these fluctuations may also present as feelings of jitteriness, restlessness, or mild anxiety between meals, reflecting the involvement of stress hormones such as adrenaline in blood sugar regulation.

Anxiety, Energy and Cravings

These symptoms are often closely interconnected and can form a reinforcing cycle over time.

For example, a meal that is mostly made up of refined carbohydrates and low in protein or fat may be digested and absorbed quickly, leading to a rapid increase in blood glucose. This is typically followed by a compensatory insulin response, which can result in a relatively sharp decline in blood sugar levels.

As blood glucose falls, the body activates counter-regulatory mechanisms to maintain energy supply to the brain. This includes the release of stress hormones such as cortisol and adrenaline, which stimulate glucose production. While this is a normal physiological response, it can also produce sensations that mirror anxiety, including a racing heart, nervousness, and increased alertness.

At the same time, the brain signals a need for quick energy, often leading to cravings for sugary or highly processed foods. If this pattern repeats regularly, it can contribute to ongoing fluctuations in energy and mood, as well as a reduced ability to tolerate stress.

Over time, supporting more stable blood glucose levels through balanced meals and regular eating patterns may help reduce this cycle and promote more consistent energy and emotional regulation. This is something I explore in more detail in my November blog on insulin resistance.

Nutrition Strategies That Support Blood Sugar Balance

The goal is not to cut carbs completely or follow hideously restrictive rules, but to support more stable blood sugar levels through balanced, consistent eating patterns.

Here are some practical strategies:

1. Build balanced meals
Include protein, healthy fats, and fibre-rich carbs at each meal. This combination helps slow the release of glucose into the bloodstream.

2. Do not skip meals
Having 3 good meals per day within a 12 hour window, can help prevent large drops in blood sugar.

3. Choose whole food carbohydrates
Opt for foods such as oats, whole grains, vegetables, and legumes – rather than bread, pasta, pastries and sugary foods - where tolerated, which provide a slower release of energy.

4. Include protein at breakfast
Starting the day with a protein-rich meal may help support more stable energy and reduce cravings later on.

5. Be mindful of caffeine
Caffeine can amplify symptoms such as jitteriness and anxiety, particularly when consumed on an empty stomach.

6. Keep it realistic
Simple, repeatable meals are often the most sustainable. Perfection is not required to see benefits.

Supporting blood sugar balance can be a helpful part of managing anxiety, but it is not a replacement for appropriate medical or psychological care where needed.

As a BANT-registered Nutritional Therapist, I do not diagnose or treat medical conditions, and I always recommend speaking with your GP if you are experiencing ongoing symptoms.