The pandemic of diabetes represents a major public health problem worldwide. (1) This modern epidemic is rather surprising considering that diabetes has been around since thousands of years and represents one of the world’s oldest disease. Ancient civilizations such as Egyptians, Indians and Persians have documented diabetes. (2, 3, 4) Diabetes prevalence increased by 50% over the past 10 years. (5) In 2017, the International Diabetes Federation (IDF) reported 425 million people suffering from diabetes worldwide which accounts for 11.2% of the world’s adult population. This number is expected to double by 2035. The annual global expenditure for diabetes health care was 727 billion dollars in 2017. (1) The greatest prevalence of Diabetes is occurring in developed countries. Despite that, Diabetes is expected to increase by 50% in the near future in the Middle East, Asia (6) and Africa. (7)
Diabetes Mellitus is a group of metabolic diseases characterized by overt hyperglycemia due to dysregulation of carbohydrate, lipid and protein metabolism resulting from impaired insulin secretion or insulin resistance, or both. In 1997, the American Diabetes Association classified Diabetes in different types and categories. Among these categories, the most common types are type 1 and type 2 diabetes. (8)
Type 1 diabetes (T1D) is an autoimmune disease affected by environmental and genetic factors resulting in the destruction of the beta cells (β-cells) within the islets of Langerhans. Type 1 diabetes is common in the young generation. Hyperglycemic individuals have no other means of survival but daily administration of exogenous insulin. Type 1 diabetes is more prevalent in developed westernized countries than in countries with low or middle income. Although type 1 diabetes individuals constitute 5-10% of the total diabetic population, its expenditure can reach up to 40% of the health care for diabetes in some countries (http://www.jdrf.org.au/about-jdrf-australia/media- room). Developed countries are suffering from a 6% increase in the risk of developing type 1 diabetes annually. This could be due to environmental triggers and to insulin resistance as seen in obese T1D patients. Moreover, the exogenous administration of insulin in T1D individuals could have a deleterious effect on insulin resistance.
Type 2 diabetes (T2D) is referred to as diabetes burden and comprises 85% of the cases. The prevalence of T2D is much greater than T1D diabetes worldwide. In T2D, insulin resistance combined with the compensatory hypersecretion of insulin by β-cells precedes insulin secretion defects. Nevertheless, hyperglycemia is only manifested after diminution in insulin secretion due to pancreatic β -cells dysfunction. In fact, along disease progression, residual insulin is still secreted. The increase in type 2 diabetes incidence is due to environmental factors. As a matter of a fact, IDF reported in 2017, 279 million people with diabetes living in urban areas compared with 146 million people with diabetes living in rural area. The number of urban people with diabetes is expected to double in 2045. The interplay of environmental factors in the urban areas is associated with obesity following life style changes and specifically the increase of caloric and dietary fat intake.
It has been reported that diabetes is associated with several complications whether acute or chronic. Acute complications include diabetic ketoacidosis following high blood glucose or hyperglycemia. While hypoglycemia or low blood glucose can lead to an individual entering a state of coma. Chronic complications include depression, dementia, sexual dysfunction and long-term vascular complications. Vascular complications can affect the small vessels and are then called “microvascular” complications or can affect the arteries and are then called “macrovascular” complications. Macrovascular complications lead to cardiovascular disease resulting in myocardial infarction and cerebrovascular disease or stroke. On the other hand, microvascular complications can affect the nerves (diabetic neuropathy) or the eye (diabetic retinopathy) or the kidneys (diabetic nephropathy).