Why is it that when we are young, we “sleep like a baby,” but start to have difficulty sleeping through the aging process? Of course, during youth, we don’t typically have the stressful burdens that accompany life, but research suggests your hormones might be the cause of many of the most common sleep complaints. Specifically, the endocrine system is linked to sleep quality and sleep duration.
Thyroid dysfunction is an interesting issue because it is associated with both lethargy and insomnia. Many patients with hypothyroidism often complain about not feeling rested or reaching deep sleep. Healthy thyroid function is required for meaningful sleep. It may sound backward, but restful sleep requires energy. An animal’s metabolic rate is partly regulated by thyroid function so if thyroid levels aren’t healthy, the body may not have the resources for deep sleep.
As confirmed by studies, many patients that have hypothyroidism don’t enter stage 3 of sleep (Song, 2019), have a more challenging time falling asleep, have shorter sleep duration, and lower satisfaction with their sleep quality compared with those with normal thyroid function. It’s not just that low thyroid can impair sleep through interrupted energy resources, but that the symptoms of hypothyroidism may also contribute to impaired sleep. For example, muscle and joint pain, cold hands and feet, and increased anxiety may contribute to sleep issues.
Chronically high cortisol in the body is often an adaptive response from a stressful environment. Unfortunately, high cortisol is heavily linked to sleep disorders. One study noted, “Patients with insomnia without depression do present high levels of cortisol, mainly in the evening and at sleep onset, suggesting that, rather than the primary cause of insomnia, the increase in cortisol may be a marker of CRH and norepinephrine activity during the night.” Sleep, stress, and cortisol may be closely related and a biomarker to look into if you have sleep issues. Unburdening the body, by meeting nutritional requirements, removing inflammatory foods, and solving chronic mental stress are key factors to lowering cortisol and maximizing sleep.
Studies show that a decrease in progesterone levels can disturb normal sleep patterns. Progesterone is a hormone known to affect sleep quality, which is why it’s often taken at night to improve deep sleep. It’s not surprising that many menopausal symptoms complain of disordered sleep, insomnia, and frequent awakenings. Many patients report a “soothing effect” from taking progesterone. In studies, progesterone has been shown to help those that have disturbed sleep. “…Sleep disturbances, which were considerably reduced under progesterone treatment…” (Caufriez, 2011). Progesterone may improve sleep by improving slow wave sleep (SWS) and slow wave activity. Another study done in animals examined the effects of three doses of progesterone (30, 90, and 180 mg/kg) administered intraperitoneally at light onset on sleep in rats. They found “decreased the amount of wakefulness and REMS, and markedly increased pre-REMS, an intermediate state between NREMS and REMS.” Progesterone itself is known to have anti-stress properties so adequate levels may be necessary to optimize sleep.
Low vitamin D.
Vitamin D is a hormone that plays many roles in the body. Vitamin D deficiency has been associated with sleep disorders likely because it impacts our metabolism through transcriptional changes (the conversion of DNA to RNA). One study confirms this and concluded, “…We found that participants with vitamin D deficiency (VDD) had a significantly increased risk of sleep disorders.” In addition, children with vitamin D deficiency have less total sleep time and poorer sleep efficiency compared with children with sufficient vitamin D. Similar to the way in which thyroid symptoms may be the cause of interrupted sleep, the symptoms of vitamin D deficiency like restless legs syndrome and obstructive sleep apnea syndrome may be contributing to sleep disorders.
We all know that frustrating feeling of not being able to fall asleep or waking up in the middle of the night. The good news is, this can be avoided. Many patients achieve peaceful sleep through renewed hormonal balance. Starting the hormone balancing journey with a simple at-home blood test like the one from Moment Health can give fantastic insight into the root causes of sleep disturbances. Good sleep is right around the corner.