Explanations

Sunshine and SADness

Liz Blamire

23rd January 2023

Today in London, we will have 8 hours and 22 minutes of daylight and 11 hours and 22 minutes of darkness. Fast forward 6 months to the longest day - June 21st - and we can expect a whopping 16 hours and 38 minutes of daylight! Combine that with average daily sun hours, which are at their absolute lowest in January at 1 to 2 hours, and January days are not just short but gloomy too.

So what?

We actually need both daylight and the sun for optimal physical and mental wellbeing. Here are the health benefits of getting enough sunlight:

  1. Improves sleep - your body clock or circadian rhythm needs a cycle of darkness and light for optimal functioning. The sleep hormone melatonin relies on this too - you need darkness in order to become sleepy, but also morning daylight to maintain the cycle
  2. Reduces stress - again, melatonin is key here, especially morning daylight
  3. Maintains strong bones - direct sunlight on our skin enables our bodies to produce Vitamin D. Vitamin D is vital for regulation of calcium levels and therefore contributes to bone health. Did you know that there is not enough sunlight in the UK from October to March for this to happen? So it is actually recommended we all take Vitamin D supplements!
  4. Strengthens the immune system - again, Vitamin D is key here
  5. Fights off depression - sunlight encourages the production of serotonin which improves mood and focus
  6. May contribute to healthy weight maintenance - almost certainly linked to your circadian rhythm and yep, you guessed it, daylight in the morning is crucial!
  7. It might even lengthen your life span - although more research is needed, this is probably due to all the positive benefits of points 1 to 6!

What is SAD?

SAD is an acronym for a mood disorder called Seasonal Affective Disorder which is more apparent or severe in the winter months. It is not fully understood but is most definitely linked to reduced exposure to sunlight in the winter months, which in turn means that the function of hypothalamus in the brain causing problems with:

  • Melatonin production
  • Serotonin production
  • Circadian rhythm regulation

Get the full down on daylight, sunshine, circadian rhythms and more by watching this video:

Liz Blamire

Liz is the tutor2u subject lead for Health & Social Care. She is a former NHS midwife, an SSAT Accredited Lead Practitioner, who has taught Health & Social Care in FE and secondary schools. Liz has extensive experience in qualification development, assessment writing, examining and moderation, and is a textbook author. Liz has an MEd in Inclusion and Special Educational Needs.

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