2025.04.27

Caution! Relationship Between Diabetes, Blood Sugar (BS), and Fasting Blood Sugar (FBS)

 

Today, we will discuss blood sugar levels and diabetes. Diabetes is a disease closely related to oxidative stress. There are several diagnostic criteria (parameters) used to diagnose diabetes.

 

 

First is fasting blood sugar (FBS). This refers to blood sugar levels measured 8 to 12 hours after eating, meaning when there is no food in your stomach. For example, if you skip dinner the day before a blood test and your blood sugar is above 120 mg/dl (milligrams per deciliter), you are clearly at risk for prediabetes.

 

Next is casual blood sugar (BS). This refers to blood sugar levels measured regardless of meal timing. It is natural for blood sugar to rise after meals. Therefore, this parameter is generally unsuitable for diabetes diagnosis.

 

Another important parameter is Hemoglobin A1c (HbA1c). This test measures how much sugar is bound to hemoglobin in red blood cells. It reflects your average blood sugar levels over approximately three months, and a high HbA1c clearly indicates diabetes.

However, even if HbA1c levels are normal, some individuals may experience sudden spikes in blood sugar after meals, known as “blood sugar spikes.” When these spikes occur, insulin is secreted, reducing blood sugar levels. Repeated spikes and rapid drops in blood sugar can damage blood vessels.

Thus, recent research indicates that a normal HbA1c does not necessarily exclude diabetes. Therefore, individuals at risk should also check if their blood sugar spikes significantly after meals.

 

How well is the relationship between diabetes and oxidative stress understood?

 

Within diabetes types, the connection between type 2 diabetes, where insulin secretion initially normal gradually declines, and oxidative stress has become clearer.

 

In type 2 diabetes, pancreatic cells become damaged by various oxidative stresses, causing reduced insulin secretion. In other words, pancreatic cells experience oxidative stress even before blood sugar levels begin rising.

 

When blood sugar levels eventually rise to diabetic levels, oxidative stress also escalates further. Thus, oxidative stress is significantly involved throughout the development and manifestation of type 2 diabetes.

 

Moreover, oxidative stress is also known to be responsible for complications associated with diabetes, such as blocked vessels in limbs, arteriosclerosis damage in the retina, and kidney failure. Therefore, diabetes can be described as a “condition of oxidative stress.”

 

Are there cases where lowering oxidative stress improved diabetes-related metrics?

 

One diabetes complication is peripheral neuropathy.

Peripheral neuropathy symptoms include tingling sensations and pain in the hands and feet. If it progresses, patients lose sensation. In one example, five individuals with peripheral neuropathy experienced significant relief from symptoms like hand numbness within about six weeks of antioxidant treatment, which reduced oxidative stress.

 

Additionally, studies involving SDT fatty rats—a rat strain prone to diabetes and severe diabetic complications—have shown promising results. Without treatment, these rats almost invariably develop severe cataracts by around 25 weeks. However, administering antioxidants to reduce oxidative stress effectively prevented cataract formation in nearly all cases.

 

Conclusion

 

We have discussed diagnostic criteria for diabetes and the relationship between diabetes and oxidative stress. Even if your diagnostic values exceed the threshold for diabetes, lifestyle improvements and lowering oxidative stress can often restore normal values. Adopting lifestyle habits that reduce oxidative stress, combined with healthy lifestyle choices, is beneficial for maintaining overall health.