Many people with diabetes ask the same frustrating question.

"I didn't eat anything overnight. So why is my fasting blood sugar still high?"

It seems to defy logic.

If no food has entered the body for eight or ten hours, shouldn't blood sugar naturally fall?

Surprisingly, the answer may have less to do with what you ate the night before than with what your liver has been doing while you slept.

The Paradox — The Liver, Not Just the Pancreas

Most people think the pancreas is the star of blood sugar control because it produces insulin. While this is true, the liver is equally important.

Working around the clock, the liver stores glucose after meals and releases it between meals, ensuring that the brain and other vital organs receive a constant supply of energy.

Under normal circumstances, insulin signals the liver when to store glucose after meals and when to reduce glucose production during fasting. However, in type 2 diabetes, the liver may become resistant to insulin's signals. Instead of slowing down glucose production, it continues releasing glucose into the bloodstream even when blood sugar is already high. As a result, fasting blood sugar may remain elevated despite having eaten nothing overnight.

This is one reason why simply eating less sugar does not always lead to better blood sugar control.

The Traditional Chinese Medicine View

Although modern science has only recently uncovered the liver's central role in blood sugar regulation, TCM has recognised the importance of healthy liver function in maintaining physiological balance for thousands of years.

In TCM, the Liver is responsible for ensuring the smooth flow of Qi throughout the body (肝主疏泄), allowing physiological processes—including metabolism—to remain balanced and coordinated. The Liver also works closely with the Spleen, which governs the transformation of food into Qi and Blood (脾主运化). Together, they form what can be understood as the Liver–Spleen Axis, supporting healthy metabolism and energy regulation.

When Liver Qi becomes constrained—often as a result of chronic stress, emotional strain, or inadequate sleep—it may disrupt the Spleen's ability to transform and distribute nutrients efficiently (肝脾不和). Over time, this may contribute to poor metabolic regulation and impaired blood sugar control.

Modern medicine describes a remarkably similar process from a physiological perspective.

Fatty liver disease is closely associated with insulin resistance and type 2 diabetes. As fat accumulates within the liver, the organ becomes less responsive to insulin and continues producing glucose when it is no longer needed. This places additional strain on blood sugar regulation and may worsen diabetes over time.

Although described using different medical frameworks, both modern medicine and TCM recognise the same fundamental principle: healthy liver function plays a central role in maintaining healthy blood sugar.

Practical Ways to Support Liver Health

Supporting your liver is an important part of diabetes management.

Helpful lifestyle habits include:

• prioritising good sleep and stress management
• developing healthy strategies for managing emotions
• engaging in regular physical activity
• reducing ultra-processed foods and added sugars
• maintaining a healthy body weight
• increasing fibre-rich foods

In TCM, several herbs and foods have traditionally been used to support Liver and Spleen function:

• Chinese Yam (山药) — strengthens the Spleen and supports metabolic health
• Goji Berries (枸杞子) — nourishes the Liver and supports overall vitality
• Poria (茯苓) — strengthens the Spleen and promotes healthy fluid metabolism
• Rose Buds (玫瑰花) — soothes Liver Qi and supports emotional well-being
• Hawthorn (山楂) — traditionally supports digestion and healthy lipid metabolism

Closing Insight

When people think about diabetes, they often focus on the pancreas.

However, healthy blood sugar depends on far more than insulin alone. It also depends on how well the liver stores, produces, and regulates glucose every hour of the day.

By supporting both liver health and the Liver–Spleen Axis through healthy lifestyle habits and appropriate TCM care, we can take a more comprehensive approach to diabetes prevention and management—one that looks beyond the pancreas and recognises the liver as one of the body's hidden guardians of metabolic health.