There are several factors that may cause high blood sugar. But the two main underlying issues are biological in nature, and they both involve a problem with the body’s insulin-producing system.
There are cells in the pancreas called beta cells that are responsible for producing insulin . After eating a meal, the beta cells begin to produce insulin that the pancreas releases in order to ensure that glucose (sugar) in food is properly broken down and transported. In healthy adults and children insulin promotes :
- The transfer of glucose from the bloodstream to liver, fat, and muscle cells, where it is used for energy or stored for later use
- The production of less insulin in response to decreasing blood glucose levels as the glucose molecules begin to enter cells throughout the body and blood glucose levels decrease.
Unfortunately, there are two main types of health problems that may lead to uncontrolled blood sugar levels.
Heredity vs. Diet and Lifestyle
The first underlying health issue linked to high blood sugar involves hereditary or environmental problem that causes the immune system to attack and destroy cells in the pancreas that produce insulin [1, 2]. This type of issue stops the pancreas from producing insulin and often develops during early childhood.
The second issue linked to high blood sugar levels that are hard to control involves an unhealthy lifestyle or poor eating habits [3, 4]. For instance, physical inactivity, saturated fat, and sugary foods, in particular, can cause blood sugar levels to quickly rise to dangerous levels. This appears to c diminish cellular responses to insulin over time — causing them to become resistant to insulin.
More specifically, impaired insulin sensitivity may develop when cells have significantly impaired response to insulin . This causes sugar to rapidly accumulate in the blood. If this happens, the cells throughout the body cannot receive glucose from the bloodstream to use it for energy or to store it as an energy reserve. Extremely high blood sugar levels may also lead to elevated levels of unhealthy fats, a fatty liver, and abnormal inflammatory responses and cardiovascular problems [3-5].
Although these two types of diabetes may lead to high blood sugar, dangerously high blood sugar that is linked to impaired insulin sensitivity is much more common than uncontrolled blood sugar due to heredity factors [1-4].
It is important to remember that although these two causes have distinct mechanisms, they are both serious issues that require proper intervention. Uncontrolled blood sugar levels that become dangerously high can lead to major health complications. High blood sugar is less of a problem than low blood sugar. Excessively low blood sugar (hypoglycemia) results in excessively low intracellular sugar concentrations, a state that starves cells of energy causing them to die. High blood sugar won’t precipitate an acute physiological crisis but low blood sugar will.
Additional Factors Linked to High Blood Sugar
Researchers and physicians do not fully understand why some people struggle with high blood sugar, while others maintain healthy blood sugar levels. However, factors that increase the risk of uncontrolled blood sugar and impaired insulin sensitivity have been identified. These include [1-5]:
- Being overweight or obese — High levels of fat are associated with abnormal inflammatory responses and increased cell resistance to insulin — issues that make it hard for the body to maintain blood sugar balance.
- Physical inactivity — People who are inactive tend to have a slower metabolism and this disrupts the body’s ability to break down fats, carbohydrates, and other food particles. Physical activity revs up metabolism, burns glucose for energy, and boosts cells’ responses to insulin.
- Age — The risk of experiencing various health problems tends to increase as individuals get older. This is the same case for blood sugar balance and it may be attributed to the loss of muscle mass or weight gain that often occurs with age or the tendency to exercise less. However, the incidence of impaired insulin sensitivity and high blood sugar is also increasing among young children, adolescents, and young adults.
- Family history — Having a parent or sibling who struggles with high blood sugar increases the risk of experiencing this health problem.
- Race or ethnicity — Individuals of certain ethnic backgrounds such as those who are African American, Asian American, American Indian, and Hispanic tend to have a higher risk of experiencing high blood sugar for reasons that are unknown.
- High blood pressure — A blood pressure reading of 140/90 millimeters of mercury (mm Hg) or higher is associated with increased high blood sugar.
- Polycystic ovaries — This health problem refers to the development of enlarged ovaries with numerous small cysts. It is linked to irregular menstruation, obesity, excessive hair growth, and an increased risk of high blood sugar.
- Unhealthy triglyceride and cholesterol levels — People who have low levels of good cholesterol, also known as high-density lipoprotein (HDL), have a higher risk of developing high blood sugar. Triglycerides, a different type of fat, travel through the bloodstream. Similar to bad cholesterol, high triglyceride levels increase the risk of experiencing uncontrolled blood sugar.
Pregnancy — Pregnant women may develop dangerously high levels of blood sugar and this increases the risk of impaired insulin sensitivity and long-term high blood sugar problems. However, some women are more susceptible to gestational blood sugar problems during pregnancy than others. Additional risk factors include:
- Personal or family history — Women who experience impaired insulin sensitivity prior to becoming pregnant have a higher risk of developing dangerously high blood sugar levels. The risk is even higher for pregnant women who have family members, such as siblings or parents, who struggle with this issue. Women are also at a greater risk of experiencing extremely high gestational blood sugar levels.
- Age — Women who are 25 years of age or older when they become pregnant are more susceptible to gestational blood sugar problems.
- Weight — Being overweight before becoming pregnant also increases the risk.
- Ethnicity or race — Women who are Hispanic, African American, Asian American, and American Indian are more likely to develop dangerously high gestational blood sugar levels for reasons that are unknown.
Overall, once the underlying factors contributing to high blood sugar are determined, the right steps need to be taken to manage it. Dietary changes, lifestyle adjustments, and beneficial dietary products can help promote sustained blood sugar balance.
- Ahmed AM. History of diabetes mellitus. Saudi Med J. 2002;23:373-8.
- Caputo T, Gilardi F, Desvergne B. From chronic overnutrition to metaflammation and insulin resistance: adipose tissue and liver contributions. FEBS Lett. 2017;591(19):3061-88.
- Christ A, Latz E. The Western lifestyle has lasting effects on metaflammation. Nat Rev Immunol. 2019;19(5):267-8.
- Nseir W, Nassar F, Assy N. Soft drinks consumption and nonalcoholic fatty liver disease. World J Gastroenterol. 2010;16:2579-88.