Vitamin A and Sleep – Getting Your “Rhythm” Right

by sleep wellness

Most of the health-consious people among us know how important role vitamin A plays in a variety of functions throughout the body and are familiar with its many benefits.

If you ar eone of them, kudos!

But, today, we’ll take an in-depth look into the role Vitamin A plays in regulating our sleep cycles and our daily circadian rhythm.

girl taking cod liver oil

Vitamin A and the Circadian rhythm

How can the brain “tell” the difference between daytime and nightime?

Without certain cells in the eye retina, known as intrinsically photosensitive retinal ganglion cells (ipRGCs), it couldn’t.

It’s the protein in these cells called melanopsin that tells the brain whether it’s day or night.

Vitamin A plays a vital role in the daily cycle of sleep by helping by helping us to not only to fall asleep on time but, in fact, get enough quality sleep, and wake up well-rested and energetic – ready for the next day and all that it brings.

Reacting to the blue light from the sun’s rays, Vitamin A and its post-cursors send a signal that tells the brain that it’s daytime. No blue light to react to and your body starts “pumping” melatonin, making you sleepy.

What hapeens when Vitamin A is lacking?

Although vitamin A is equally important both for daytime and night vision, in the case of its insufficient intake, the daily vision takes precedence, so that night blindness is considered the most sensitive sign of vitamin A deficiency.

However, it’s our circadian rhythm that take a more significant hit from the lack of vitamin A than the loss of night vision. So you are experiencing a  disrupted circadian rhythm, you should take a nice long look into your Vitamin A intake.

mechanism of circadian rhythm and melatonin release illustration

How does the Vitamin A Support Sleep?

If you can’t fall asleep on time or get enough quality sleep and you don’t wake up well-rested and energetic, you might have a disruption in your circadian rhythm.

The first sign that your problems might be related related to a vitamin A deficiency is an abnormal reaction to blue light (in laymans’s terms – it’s dark out but you don’t feel like sleeping).

happy young girl in the sun

In today’s life circumstances, an average person has the option to control their own light and temperature exposure, which can be both good and bad.

The problem of modern society is that people usually work in an environment with artificial lighting that is nowhere near as bright as the sun outside (and we keep these blue light sources on at night, too, which gives us far more blue light than the moon or a campfire would).

To put it simply – we get too much blue light at night and that we don’t get enough during the day.

Small changes go a long way – below are a few tips on how to make them:

  • Make sure that your environmental temperature peaks in the day and declines during the night (if the room you sleep is not air-conditioned, a good cooling mattress pad is a smart choice)
  • Spend at least a half an hour in the outside sun soon after waking up in the morning
  • Use dim light at night and to use blue light-blocking technology (blue-blocking glasses and apps) for our devices (TV, phone, computer)
  • If your mattress is located in way that, in your favorite sleep position, you get any glare from blue light (like street lights), think about moving it to a different corner of your bedroom
family taking a morning walk

How to make sure you’re getting
enough of Vitamin A

The animal sources supply vitamin A as retinol, a form that our body requires, while plant sources supply carotenoids of provitamin A that can be converted into retinol.

Since not all people have the same ability to convert A carotenoids into retinol, it’s important to note that plant foods can’t be substitute for animal foods in the long run.

The best way to make sure that the intake of vitamin A is sufficient is to eat a serving of liver once per week and/or a serving of cod liver oil once per day. Eggs and whole milk are also solid sources of the Vitamin.

basket of wild plums

From the foods occuring in the wild, the Wild Plum (Prunus Americana and Prunus Nigrica) stands out.

Just 5 oz of  wild plums give you 164 % of RDA of vitamin A.

Keep in mind that vitamin A, like any other nutrient, doesn’t do its job “alone”.

The main intake of vitamins and minerals should be a balanced diet, and diets supplements should be used only as an addition to strengthening one nutrient.

We’re not all the same – the story
our eyes tell

It’s a given that some people might need higher vitamin A intakes than others.

There isn’t any clear evidence of the role of eye color, but it might be that people with lightly colored eyes need more vitamin A because lightly colored eyes let in more blue and UV light.

However, it is possible that many other factors, such as the genetic variation of enzymes that degrade vitamin A, the health condition that affects the rate of use of vitamin A, and the status of nutrients that work with vitamin A, have their own influence on the increased need for this vitamin.

baby boy with blue eyes


  • Bob Ozment

    Bob has been testing and writing about all things sleep (and especially blankets, air mattresses and folding beds), for 8+ years now. before that, he worked as a Quality Assurance Manager with one of the bigger names in the sleep industry. He holds a masters degree Statistics, Actuarial & Data Sciences from the central Michigan University at Mount Pleasant. He's one of the people who designs our producing testing and statistical models. He’s a stomach sleeper, but nobody’s perfect.