Blood sugar, it can be argued, is what keeps our bodies functioning properly.

Sugars enter the blood after being consumed and digested to their simplest forms. However, when disease alters normal levels of these sugars in the blood, other impairments can occur.

Blood sugar level is carefully monitored by the body. If there is too much sugar, the body releases a hormone called insulin to signal the rest of the body to absorb more of the sugar. Similarly, if there is too little sugar, the body has signals to increase levels of sugar in the blood. However, when a person has diabetes, these monitoring systems do not work naturally and the individuals must inject insulin into their bodies so that blood sugar can decrease.

Diabetes patients often have very high blood sugar. Their bodies are never signaled to use the sugar in their blood, so it remains there. This is not optimal, as the body needs the sugars consumed. Diabetes treatments thus provide the hormone that allows for sugar absorption and use.

Often, as a result of diabetes treatments, blood sugar can get too low and is called hypoglycemia. During hypoglycemia, other studies have found that cognitive functions are impaired: attention and motor skills are impaired and response times are much slower. Similarly, patients may suffer from headaches and become nauseous.

In a new study among older adults, hypoglycemia has been associated with dementia and the development of Alzheimer's disease. When the body has a low level of blood sugar, cognitive function is impaired and severe hypoglycemia may cause neuronal damage, leading to dementia and Alzheimer's.

In a study of 783 older adults with diabetes during a 12-year period, eight percent reported a hypoglycemic event and 199 percent developed dementia over time. Patients who experienced a hypoglycemic event had a two-fold increased risk for developing dementia compared to those who did not have a hypoglycemic event. Similarly, history of hypoglycemia increased the likelihood of poor cognitive function later in life.

According to these findings, low blood sugar and dementia seem to be interrelated. Not only does low blood sugar cause cognitive decline into dementia, but dementia can also create low blood sugar. Older adults with diabetes who developed dementia had a greater risk for having a subsequent hypoglycemic event compared to patients who did not develop dementia.

Hypoglycemia in diabetes patients causes very clear and poor outcomes. The body many enter a starvation mode, and as a result, cognitive decline may ensue. The researchers have concluded that treatments for diabetes patients should be altered to focus on other nutrients, not just sugars, to prevent the likelihood of hypoglycemia.

Source: Yaffe K, Falvey CM, Hamilton N, et al. Association between Hypoglycemia and Dementia in a Biracial Cohort of Older Adults with Diabetes Mellitus. JAMA. 2013.