Which Type of Diabetes Do I Have?

Diabetes is generally known to be grouped into two general types – type 1 and type 2. In standard language, type 1 denotes a lack of insulin production by the pancreas (also known as “insulin deficiency”). Type 2 diabetes denotes intact insulin production by the pancreas (sometimes even substantially increased), but insulin molecules are unable to effectively remove sugar from the bloodstream (known as “insulin resistance”). However, this classification into type 1 and type 2 is somewhat arbitrary. It serves the general purpose of categorizing people who need insulin therapy versus those who do not. Many individuals have a mix of both insulin deficiency and insulin resistance. This explains why some patients with type 2 diabetes may need insulin therapy, even if only for a limited period.

Insulin’s Role in Glucose Metabolism:

Obesity and overweight often lead to insulin resistance, where insulin cannot effectively uptake glucose from the bloodstream. Insulin, when functioning properly, shuttles glucose into skeletal muscle cells for fuel, stores glucose as triglycerides in fat tissues, and packages glucose into glycogen chains in the liver.

The Liver as a Glucostat:

The liver plays a key role in maintaining blood glucose levels, acting like a “Glucostat.” by either releasing or storing glucose in the liver “glucose treasury”. This enables a steady glucose supply for all situations of increased (e.g. physical activity, prolonged fasting) or reduced glucose demand (e.g. meal intake, sleep) by the body. The liver meets increased glucose demand with the help of metabolic processes (“transactions”) called glycogenolysis and gluconeogenesis. In diabetes, the “Glucostat” is broken and dysregulated as the release of glucose into the blood stream is ongoing regardless of physical activity, meal intake or sleep. This often explains why many individuals report elevated glucose levels even though there has been little or no carbohydrate intake for a significant period of time.

Organs Dependent on Glucose:

Certain organs, such as the brain, kidneys, testicles, and ovaries, heavily rely on glucose as their primary energy source. In emergencies, they can use alternative fuels like ketones and fats, though less efficiently. The lens of the eye and red blood cells are almost exclusively dependent on glucose. However, too much of a good thing isn’t always good and early symptoms of glucose excess in the tissues of these organs include fatigue, brain fog, numbness, frequent urination, dehydration, and blurry vision. These symptoms highlight the importance of managing glucose levels to maintain overall health.

Speak with your healthcare team about if and for how long you would benefit from insulin therapy and what diabetes medication (if any) would be optimal for your individual circumstances and condition. 

References and Further Reading:

1.      American Diabetes Association. (2022). Diagnosis and classification of diabetes mellitus. Diabetes Care, 45(Supplement 1), S17-S38

2.      DeFronzo, R. A. (2004). Pathogenesis of type 2 diabetes mellitus. Medical Clinics of North America, 88(4), 787-835. 

3.      Saltiel, A. R., & Olefsky, J. M. (2017). Inflammatory mechanisms linking obesity and metabolic disease. The Journal of Clinical Investigation, 127(1), 1-4.

4.      Zhang L, Qin Y, Huang Y, et al. Abnormal late postprandial glucagon response in type 1 diabetes is a function of differences in stimulated C-peptide concentrations. Front Endocrinol (Lausanne). 2024;15:1419329. Published 2024 Aug 1. doi:10.3389/fendo.2024.1419329

5.      Shulman, G. I. (2000). Cellular mechanisms of insulin resistance. The Journal of Clinical Investigation, 106(2), 171-176.

6.      Exton, J. H. (1972). Regulation of hepatic glucose metabolism. Annual Review of Biochemistry, 41(1), 301-324.

7.      Moore, M. C., Coate, K. C., Winnick, J. J., An, Z., & Cherrington, A. D. (2012). Regulation of hepatic glucose uptake and storage in vivo. Advances in Nutrition, 3(3), 286-294. 

8.      Magistretti, P. J., & Allaman, I. (2015). A cellular perspective on brain energy metabolism and functional imaging. Neuron, 86(4), 883-901.

Häggström, Mikael (2014). “Medical gallery of Mikael Häggström 2014”. WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.008. ISSN 2002-4436. Public Domain.orBy Mikael Häggström, used with permission., Public domain, via Wikimedia Commons