A Disease of (Modern) Proportions?
Diabetes, both Type 1 and 2, are conditions characterized by impaired blood sugar regulation. Our modern lifestyle has produced an environment that our body struggles to adapt to – many of us have access to an abundance of food, particularly chemically-laden and calorically dense processed foods, are chronically exposed to environmental toxins, and lead mostly sedentary lives. All of these factors contribute to the development of Type 2 Diabetes, a condition that has been described as a ‘disease of civilization’. Inflammation and irregular blood sugar can result from our modern way of life, paving the way for the development of insulin resistance, an inability to respond to the blood sugar-regulating effects of insulin. Insulin resistance plays a key role in the pathophysiology of metabolic syndrome, a cluster of symptoms that act as a major risk factor for cardiovascular disease and type II diabetes.(1,2) It is estimated that 3.4 million Canadians currently have diabetes and that number is expected to grow by 44% by 2025.(3) People with diabetes are more than three times likely to be hospitalized with cardiovascular disease.(4) Rates of Type 2 Diabetes amongst children and adolescents are increasing worldwide. (5) The treatment of diabetes and the associated complications creates a huge economic burden and costs are expected to skyrocket through the foreseeable future.(6)
Warning, Warning: Insulin Resistance
When we consume carbohydrates – such as those found in fruit, vegetables, whole grains, and many other foods – our blood sugar increases. In response to this increase, the pancreas releases insulin to move the glucose into cells and signal to the liver to convert the glucose into glycogen, a storage form of glucose, to store until our blood sugar drops. If there is an excess of glucose, the body can also convert it to triglycerides that are stored in the liver or fat cells.
If our body is sensitive to the effects of insulin, we need less insulin to normalize blood glucose levels. This is the healthy response. However, under the influence of chronic inflammation, our cells become less responsive to insulin.(7) More insulin is then required to maintain blood sugar levels. This lack of response to insulin, known as insulin resistance, predisposes us to the development of Type II Diabetes.(8) A resistance to insulin results in hyperglycemia (high blood sugar), a well-known cause of inflammation in the body.(9) Therefore, inflammation lies at the root of insulin resistance and is additionally a result of insulin resistance.(10) Abnormalities in blood sugar and the development of insulin resistance can occur slowly over time as a result of this inflammatory cycle, preceding the development of diabetes and cardiovascular by many years. However, if the inflammation and insulin resistance continues, the Beta cells of the pancreas (the cells that produce insulin), become dysfunctional and unable to produce insulin, leading to the development of full-fledged Type II Diabetes.(11)
What’s inflammation got to do with it?
We are only just beginning to understand the role of chronic inflammation in the development of insulin resistance and diabetes.(12) Many factors contribute to inflammation, including dietary components such as food sensitivities (13), refined grains (14), industrial seed oils (15), and fructose (16); environmental toxins (17); stress (18); sleep deprivation (19); sedentary lifestyle (20); genetic factors (21); altered gut microbiome (22); and nutrient status. (23) Fat cells are also considered pro-inflammatory; this may be due to inflammatory chemicals that fat cells produce, hormonal shifts that occur as a result of adipose tissue, or the strain on mitochondria, the energy factories of cells, that fat creates.(24,25) Inflammation can directly influence the development of insulin resistance and leptin resistance (1,26) and impair fat metabolism (27); all of these processes contribute to the development of diabetes. Although there is a genetic component of Type 2 Diabetes, interactions with certain environmental factors are required to ’turn on’ the disease progression.(28)
Chronic inflammation is highly damaging both to the mechanisms that control glucose metabolism, as well as other areas of the body. Elevated blood sugar additionally creates inflammation.(9) Both of these factors may explain why diabetes is associated with many other health issues such as heart disease, kidney disease, nerve, and eye damage, and is associated with higher risk of stroke.(29) Inflammation appears to be the common thread between insulin resistance, cardiovascular disease, and diabetes.(30)
Diabetes and heart disease are largely considered modern epidemics directly correlated to the inflammation caused by our modern diet and lifestyle. Depending on the stage of impaired glucose metabolism, traditional treatments aim to improve insulin sensitivity, or completely replace insulin production, if the pancreas can no longer produce it. However, it is wise to consider the root cause of these health concerns – dietary and lifestyle factors and the resulting inflammation.
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4. Canadian Diabetes Association Clinical Practice Guidelines Expert Committee. (2013). Canadian Diabetes Association 2013 Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada. Can J Diabetes, 37.