What Is Fnss And How Does One Live With It?

What Is FNSS And How Does One Live With It?

January 9, 2018
Healthy Sleep

Most adults require around eight hours of sleep each night, with children and teenagers needing even more. However, some people, specifically those with a variant of the BHLHE41 gene, may be genetically predisposed to a resistance to sleep deprivation effects.

The condition is known as FNSS (Familial Natural Short Sleepers) or SSS (Short Sleepers Syndrome), and individuals experiencing it tend to get by with fewer than six hours of sleep each night with no adverse side effects. They do not require as much sleep as an average adult and can function normally with less downtime at night.

Margaret Thatcher, former British Prime Minister, is believed to have FNSS and only sleeps four hours nightly. Another possible candidate includes Thomas Edison, inventor of the light bulb, who slept only three hours nightly and claimed that sleep was unnecessary and a “heritage from our cave days.” Even Donald Trump, President of the United States, who claims to sleep three to four hours nightly, stated, “How do somebody that’s sleeping 12 and 14 hours a day compete with someone that’s sleeping three or four?”

Some people restrict the amount of sleep they get in order to give them an edge up on their competition – possibly the CEO of Square and Twitter founder, Jack Dorsey; the Chairman and CEO of PepsiCo, Indra Nooyi; and the CEO of Apple, Tim Cook. All three successful business people sleep less than five hours each day. However, this does not actually mean they have FNSS.

What is FNSS?

Researchers compared 100 pairs of twins and found one twin in a single set that slept an hour less than his brother. They uncovered that he had the p.Tyr32His variant of the BHLEH441 gene. Not only did he sleepless, but he also recorded fewer mental errors throughout a 38-period of wakefulness. After experiencing true sleep deprivation, he required less recovery time than his twin. This research was reported in the August 14, 2009, issue of the journal Science.

People with FNSS naturally require less sleep and do not purposely avoid sleep. Their short sleep pattern extends into the weekend and on holidays when most people choose to sleep in and “catch up” on their rest. The variant of this gene is an uncommon occurrence but usually starts showing in people beginning in childhood or adolescence.

Symptoms of a Sleep Problem

People with FNSS sleep fewer than six hours each night and can still perform well at work or school without issues caused by their sleep duration. Additionally, they don’t feel tired or as if they haven’t had enough sleep like one who consistently underslept may feel.

FNSS is not a sleep problem, but if you experience the above symptoms along with any of the following, you may not have FNSS, but rather a sleep disorder. Contact your doctor if you feel:

  • A fatigued feeling throughout the day
  • The urge to take a nap during non-sleeping hours
  • Difficulty falling asleep at night
  • Trouble staying asleep at night
  • Waking up often during the night

Diagnosing FNSS

In most cases, if you truly have FNSS, there is no real need to be tested. As long as you are getting enough sleep for your body and not feeling any fogginess or grogginess upon waking, then take advantage of the extra time available to you each day.

However, if you would like to be tested, your doctor will most likely begin with a Morningness-Eveningness Questionnaire to assess your sleep habits. There are 19 questions in this assessment, which will help you chronicle your typical day. The Munich Chronotype Questionnaire is used to determine if you are a morning or night person.

In addition to the questionnaires, your doctor may ask you to keep a sleep diary for several days to a week. In it, you will record:

  • The total time spent awake
  • The total time spent sleeping
  • The number of times you wake up nightly
  • The duration of any awake periods at night
  • Symptoms you experience during the daytime, such as sleepiness or the urge to nap

If you were born with FNSS, which can be hereditary, you most likely will not receive further testing. There is no need for blood work to test for the p.Tyr32His variant of the BHLEH441 gene, as you have no disorder.

However, those who deny themselves sleep may have an unhealthy sleep pattern. Their doctor may ask them to take a couple of laboratory tests to determine the extent and results of this issue, which may include:

  • Polysomnography – This sleep study is performed in a bedroom-style lab environment. There will be all of the comforts of home or a hotel room, but before going to sleep, you will be hooked up to monitors by electrodes on your scalp, arms, legs, and chest. While sleeping, a lab technician will monitor your brain waves, oxygen levels, heart rate, breathing rate, and any other necessary data in order to make an informed diagnosis.
  • Actigraphy – This longer, yet less intrusive, test involves wearing an actigraph, which is a portable monitoring device. It will digitally monitor your activities throughout the day, including heart rate, breathing rate, and other physical symptoms in order to determine your wakefulness and your sleeping periods. An actigraphy is often given simultaneously with a sleep diary.

How To Live With FNSS

FNSS is not a disorder and can be truly beneficial to have. These individuals tend to awaken refreshed and have no trouble falling asleep again in the evening, yet they only require approximately six hours or less of sleep each night. They typically do not feel the afternoon drowsiness that many others experience.

If you do have a sleep disorder, you may need treatment from your doctor depending on the severity of the situation. You may try sleep hygiene, light therapy, and resetting your sleep schedule as effective solutions to your sleep issues.

Sleep Hygiene

Sleep hygiene involves maintaining new healthy sleep habits to ensure you fall asleep and stay asleep at night. The National Sleep Foundation recommends:

  • Limiting naps
  • Avoiding stimulants before bed, such as caffeine and nicotine
  • Avoid alcohol use at night
  • Exercise regularly
  • Avoid eating right before bed
  • Expose yourself to natural light daily
  • Develop a relaxing nighttime ritual
  • Ensure a comfortable sleep environment

Light Therapy

Light therapy involves using natural or artificial light to regulate sleep. The artificial lighting must be from a special machine, called a lightbox, which produces full-spectrum light to duplicate sunlight. This will help in especially cloudy areas or during the fall and winter months when daylight hours are shortened. It’s also an effective treatment for people who work night shift so that their bodies experience night time as the day.


This cognitive-behavioral technique helps you retrain the body to recognize an acceptable sleep schedule. This is a long-term option for re-experiencing sleep and renewing the body’s ability to control its own sleep schedule.

Good Night

If you have a sleep disorder, you can effectively control your sleep issues, possibly even without the use of medication. Once your disorder is under control, you should be able to live your life with a healthy sleep schedule.

If you find that you have FNSS, then congratulations are in order. Enjoy your extra two hours of wakefulness each day and ensure a healthy six hours of sleep each night.