An Introduction to the Link Between Type 2 Diabetes and Obesity
“Even ambrosia can turn into poison when consumed beyond limits” is a common saying I often hear. Just as the saying goes, the food that we consume every day and the sugar content present within these foods are vital for our survival and “fuel us” by providing the energy we need.
However, when the food and sugar we consume increase beyond healthy limits, obesity and diabetes may result. Diabetes and obesity cases are increasing worldwide at an alarmingly high rate [1, 2]. Studies have shown that Type 2 Diabetes and obesity are highly interlinked. Obesity is one of the main risk factors for developing Type 2 Diabetes. A study conducted in 2014 in the United Kingdom revealed that more than 80% of Type 2 Diabetes patients are also obese .
How does our body react to sugar?
Type 2 Diabetes is a disorder characterised by increased blood sugar levels . Sugar enters our bloodstream when we consume foods rich in carbohydrates. Sugar is one of the main components of our diet that provides us with energy. Immediately after we eat a meal, the sugar level in our blood will “spike”. Don’t worry, this is normal and will even occur in healthy individuals. Our body then secretes a protein called insulin into the blood for our cells (especially our muscle, fat and liver cells) to take up the sugar from the bloodstream. The secreted insulin attaches to cell surface receptors and forms channels for the cells to take up the sugar, eventually returning our blood sugar to baseline levels .
The onset of Type 2 Diabetes
Insulin resistance occurs when the cells in our body stop responding adequately to the insulin secreted, which leaves sugar circulating in our bloodstream rather than being stored for further use in our muscle, fat or liver cells. Insulin resistance is one of the initial factors that trigger Type 2 Diabetes. There are drugs like metformin that improve insulin sensitivity, but these have a limited scope in terms of utilization and benefits.
Obesity and how it is related to Type 2 Diabetes
Obesity is a disorder caused by an imbalance between the energy consumed as food (calories) and the energy used by our body (during physical activities and regular functioning of the body). Obesity occurs mainly due to changes in dietary habits and lifestyle. Body Mass Index (BMI) is an indicator of obesity (Figure 1). Developments in technology, while improving productivity, have on the whole, driven individuals towards a sedentary lifestyle. Furthermore, physical activity has been limited largely to sports and gyms, whereas in the past it was integrated into our day to day activities. It should also be mentioned that our eating style has moved towards quicker preparations and unhealthier, processed options, often high in sugar.
So what does this mean for us? Unhealthy food habits which involve an excessive consumption of foods rich in sugar lead to excess energy in the body. This unused energy is deposited as fats and leads to increased sugar levels in our blood. While our body is designed to process high sugar loads in the short term, over a longer time frame, sugar in the bloodstream is not adequately taken up by the body and this leads to insulin resistance . Insulin resistance is the common underling cause for both Type 2 Diabetes and obesity [8, 9]. Improving insulin sensitivity along with regulated diet practice can be helpful in restoring a diabetes-free and obesity-free state.
So what are the implications to your health when you have insulin resistance and sugar circulating in your blood? Stay tuned to the next blog post to find out.
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2. Jain, S. and S. Saraf, Type 2 diabetes mellitus--Its global prevalence and therapeutic strategies. Diabetes and Metabolic Syndrome: Clinical Research and Reviews, 2010 4(1): p. 48-56.
3. The Lancet Diabetes & Endocrinology: Weight loss surgery substantially reduces the risk of developing type 2 diabetes. The Lancet.
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5. Subramanian, K., Kinetics of insulin - insulin receptor interaction using a surface plasmon resonance (SPR). 2014, University of Canterbury.
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9. Gallagher, E.J., D. LeRoith, and E. Karnieli, Insulin Resistance in Obesity as the Underlying Cause for the Metabolic Syndrome. Mount Sinai Journal of Medicine: A Journal of Translational and Personalized Medicine, 2010. 77(5): p. 511-523. By: Kannan Subramanian