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Setting Your Internal Clock

Dr. Lisa Varadi
28 February 2018
Setting Your Internal Clock
by Dr. Lisa Varadi

Setting Your Internal Clock

Do you find yourself tired in the early evening? This is certainly not uncommon if you have just had an intense workout, eaten a large meal or had an exceptionally exhausting day. However, if you find that you are very tired at an unusually early hour, around 6pm or 7pm, you may be suffering from a sleep disorder known as Advanced Sleep Phase Syndrome (ASPS). ASPS is one of a group of sleep disorders known as the circadian rhythm sleep-wake disorders.

Unlike insomnia (which is when a person has difficulty falling asleep and/or staying asleep) the circadian rhythm sleep-wake disorders do not affect the duration of sleep. Most people with a circadian rhythm sleep-wake disorder get the ideal seven to eight hours of sleep per night. What is affected with these disorders is the timing of sleep. For those suffering from ASPS, they may fall asleep at 6 pm and be wide awake and ready to start their day at 4 am. These early birds have no issue with getting to sleep, they just get their required hours at an atypical time.

The other situation, which is far more common than ASPS, is Delayed Sleep Phase Syndrome (DSPS). This is when a person falls asleep very late at night, or in the early hours of the morning, and sleeps in very late. These people are often referred to as night owls. This sleep disorder is common amongst teenagers, so it is suspected that it may be linked to changes that occur after puberty (1).

Setting Your Internal Clock

Both ASPS and DSPS can create immense challenges in dealing with routine tasks and responsibilities. Getting up in the morning to go to school or work can be extremely difficult for a person suffering from DSPS. Spending time with loved ones in the evenings can be a struggle for a person experiencing ASPS. Long-standing ASPS and DSPS increase the likelihood of developing depression. DSPS has linked to poor academic performance (2). Circadian rhythm sleep-wake disorders have also been linked to an increased risk of developing cardiovascular disease (3).

What is the Circadian Rhythm?

The circadian rhythm refers to those biological processes that occur (and fluctuate) over a 24-hour period. Examples of these biological rhythms are the sleep-wake cycle and core body temperature fluctuations.

The circadian rhythm is regulated in a part of the brain called the suprachiasmatic nucleus (SCN). The SCN detects signals from the eyes regarding the amount of light or darkness. Light is the strongest regulator of the sleep-wake cycle.

Setting Your Internal Clock

Upon receiving information from the external environment regarding the presence or absence of light, the SCN sends a signal to an area of the brain called the pineal gland. The pineal gland secretes melatonin. The secretion of melatonin increases at night and is almost absent during daylight hours. A peak in the secretion of melatonin tells the body that it’s time to sleep.

What Causes Circadian Rhythm Disruption?

Exposure to bright light at an atypical time can shift the circadian rhythm. Shift work and jet lag can alter a person’s biological rhythms. A slight delay of the internal clock is a normal occurrence after puberty. Some researchers have suggested that DSPS may be an exaggerated response to this delay (1). Too much screen time at night may play in role in the development of DSPS (4). Genetics is also thought to play a role in determining the likelihood that a person will develop a circadian rhythm sleep-wake disorder (5).

How Are Circadian Rhythm Sleep-Wake Disorders Diagnosed?

If your doctor suspects that you may be suffering from a circadian rhythm sleep-wake disorder, he or she will likely send you for an overnight sleep study. You may also have your melatonin levels checked. Temperature measurements and other hormone levels may also be assessed because these are biological rhythms that also fluctuate over a 24-hour period.

How Are Circadian Rhythm Sleep-Wake Disorders Treated? Setting Your Internal Clock

Melatonin and bright light exposure are often used to treat both ASPS and DSPS. This is because both melatonin and light are key regulators of the sleep-wake cycle. The timing of the treatments is determined based on the circadian rhythm sleep-wake disorder that you have and your desired sleep time. Sometimes, sleeping pills may also be prescribed to help you fall asleep at a specific time. When using bright light to treat a circadian rhythm sleep-wake disorder, ensuring that exposure occurs at the right time is key. For example, exposing someone suffering from DSPS to bright light at night can make their condition worse.

What Are the Naturopathic Treatment Options for Circadian Rhythm Sleep-Wake Disorders?

Naturopathic treatment for circadian rhythm sleep-wake disorders involves implementing dietary and lifestyle changes that support sleep and regulate the circadian rhythm.


  • Eat small, frequent meals throughout the day
  • Avoid heavily sweetened and processed foods
  • Avoid citrus, garlic, onions, peppermint and spicy foods within three hours of going to bed
  • Avoid caffeine within eight hours of going to bed
  • Drink water as your primary beverage
  • Melatonin is made from the amino acid tryptophan. Increase your consumption of tryptophan-rich foods, including lean meats, beans and eggs
  • Tryptophan requires the presence of carbohydrates to enter the brain. Increase your consumption of unprocessed carbohydrates such as whole grains, legumes, vegetables and fruit
  • Zinc deficiency is common in those who suffer from anxiety, depression, insomnia, circadian rhythm sleep-wake disorders and ADHD. Zinc also supports the production of melatonin. Increase your consumption of zinc-rich foods such as nuts, seeds, beans, lean meats and fresh seafood
  • Magnesium is very calming and supports the production of melatonin. Increase your consumption of magnesium-rich foods such as nuts, seeds, beans and green-leafy vegetables
  • Vitamin C supports the production of melatonin. Increase your consumption of vitamin C-rich foods including bell peppers, kiwi, guava, berries and citrus fruit.
Setting Your Internal Clock


  • Vitamin B6: Vitamin B6 is vital for the synthesis of hormones and neurotransmitters. Vitamin B6 also helps regulate the body’s response to stress. Chronic stress and frequent nighttime worry can significantly shift the body’s internal clock.
  • Vitamin B12: Vitamin B12 is extremely important for mood balance and nervous system function. Studies have found that vitamin B12, when combined with bright light therapy, may be helpful in the treatment of DSPS (6).
  • Omega-3 Fatty Acids: Omega-3 fatty acids are essential for the proper functioning of the brain and nervous system.
  • Supplementing with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) has been shown to play a role in improving sleep and supporting the body’s biological rhythms. Omega-3 fatty acids are also used to treat a number of conditions, including anxiety, depression, bipolar disorder, schizophrenia, cardiovascular disease and a number of inflammatory conditions.
  • S-adenosyl methionine (SAMe): SAMe is a key player in the synthesis and breakdown of many hormones and neurotransmitters, including melatonin.
  • Vitamin D: Vitamin D deficiency is common in those who experience sleep disorders, anxiety or depression.
  • Probiotics: Gastrointestinal symptoms (such as pain, nausea, bloating and constipation) are common in those who suffer from circadian rhythm sleep-wake disorders. Probiotics can help support proper digestive function. Probiotics have also been found to increase levels of sleep-promoting neurotransmitters in the brain.
Setting Your Internal Clock


  • Increase your exposure to bright, natural light throughout the daytime
  • Exercise regularly
  • Avoid using your TV, phone and tablet within three hours of going to bed
  • Set aside a “problem-solving and planning hour” at least two hours before bedtime to address any worries and work through any problems or obstacles that you may have
  • Do a relaxing activity before bed such as deep breathing or meditating
  • Go to bed and wake up at the same time every day, even on weekends and holidays
  • Keep your bedroom quiet, cool and dark
  • If you can’t sleep after 15 minutes, get up and go to another room and do a relaxing activity such as reading or listening to calming music