Sleep issues in people with diabetes can lead to greater insulin resistance (the inability of the body to use insulin efficiently) more difficulties in controlling high sugars, and development of diabetic complications.
There are a number of reasons why people with diabetes have trouble sleeping. High glucose levels at night can prompt the kidneys to excrete extra sugar in the urine, which can mean additional trips to the bathroom and disrupted sleep.
Other common sleep difficulties for people with diabetes include sleep apnea, a disorder characterized by loud snoring and pauses in breathing. Restless legs syndrome (RLS), where uncomfortable uncontrolled movements of the legs can occur during relaxation or while laying down, can occur in people who have peripheral neuropathy or nerve damage from chronically high or uncontrolled blood glucose levels.
Problems with sleep in people with diabetes have also been linked to a drop in melatonin, a hormone primarily produced by the pineal gland. Melatonin regulates circadian rhythms or the 24-hour sleep/wake, dark/light cycle.
During the night, melatonin production peaks, then drops off during the day. The less melatonin you have at night, the less chance of a good night’s sleep.
A number of recent studies reveal a connection between poor sleep, melatonin production, circadian rhythms and insulin.
Melatonin’s main job is to regulate circadian rhythms: the night and day or sleep-wake cycles. Darkness causes the body to produce more melatonin, which signals the body to prepare for sleep. Light decreases melatonin production and signals the body to prepare for being awake.
In addition to preparing the body’s internal clock for sleep, melatonin is thought to influence the release of insulin from the pancreas, which in turn regulates the level of sugar in the blood.
Circadian rhythms can influence sleeping, eating, heart rate, blood pressure, body temperature, the levels of certain hormones, and the immune system. Levels of both insulin and the hormones that raise blood sugar and work against insulin are influenced by circadian rhythms.
Interestingly, during the day, high levels of insulin occur when melatonin concentration is reduced; while during the night insulin levels drop while melatonin and glucose levels rise.
Disruptions in this rising and falling cycle of melatonin can lead to disordered sleep. It also can impact the body’s ability to use insulin.
Insulin resistance is a basic characteristic of type 2 diabetes. When there are problems with the production of melatonin, it can trigger a higher level of insulin resistance and make it harder to control high sugars.
In a 2011 study published in Diabetes Care, researchers suggested that poor sleep might contribute to worse outcomes in people with diabetes.1 The investigation of 40 people found that poor quality of sleep in people with diabetes was associated with worse control of blood sugars and a higher risk for diabetic complications.
Poor sleep has also been associated with the development of diabetes. In a study of a subset of 740 women from the Nurse’s Health Study, one of the longest and largest running investigations of women’s health, researchers found that women who secreted the least melatonin – and suffered from disordered sleep — during the night had double the risk of developing type 2 diabetes.2
No matter what the cause, treating sleep disorders from sleep apnea to insomnia may also help control diabetes. Restoring a healthy amount of sleep may prove to be a powerful and important intervention.