Where’s the sunshine? Looking after your mental health during the winter.
Often referred to as the sunshine vitamin because of its synthesis in the sun’s UV rays, vitamin D is an essential nutrient for health. Whilst many would associate this vitamin with bone health and the immune system, did you know that low levels of vitamin D can actually impact our mental health? [1]
What are the sources of vitamin D?
The main source of vitamin D comes from the sun. Our skin naturally contains a precursor of vitamin D which requires UVB radiation to become an active source of vitamin D in the body. In the UK, we can only synthesise vitamin D between March and September, as the sun’s rays aren’t strong enough during the colder months.
Therefore, during autumn and winter, it’s more important than ever to eat a balanced diet that supports our wellbeing. Foods that provide a source of vitamin D include:
- Oily fish such as salmon, sardines and mackerel
- Red meat
- Egg yolks
- Some mushrooms (if grown in/exposed to sunlight)
- Some fortified foods, such as tofu, breakfast cereals and dairy alternatives.
However, it can be difficult to obtain enough vitamin D from food sources alone, so it is advised adults and children over 4 years of age should consider taking a daily supplement containing 10 micrograms of vitamin D during the colder months.
What’s the link between vitamin D and mental health?
The mechanism by which vitamin D may be associated with mental disorders is not clearly understood. However, one theory is that there are vitamin D receptors in the hypothalamus that may be involved in neuroendocrine functioning [2].
There are numerous complex systems that help regulate our mood and mental wellbeing, with vitamin D thought to be involved in the synthesis of brain serotonin [3]. Serotonin plays an important role in mood regulation and sleep. Disruption in the body’s ability to produce serotonin can create feelings of low mood, disrupt sleep quality and is thought to be involved with some mood disorders [4].
Unfortunately, teenagers have been highlighted as a high risk group for vitamin D deficiency, with 37% 11-18 year olds in the UK vitamin D deficient by the end of winter months [5]. This may be due to spending less time outside, lack of supplementation in the winter, or lack of dietary sources of vitamin D. Those with darker skin may also have a higher risk of deficiency. This is because the melanin within the skin can absorb the UV rays required to initiate vitamin D synthesis.
What can I do over the winter months?
It is recommended that those above the age of 4 should take a daily supplement of vitamin D. However, changes in sunlight during the winter (i.e. shorter daylight hours) can impact more than vitamin D synthesis. Seasonal affective disorder (SAD) is a condition that causes feelings of depression in certain seasons, particularly autumn and winter.
It is believed that the reduced exposure to sunlight during this time can also impact the hypothalamus, causing symptoms such as:
- a persistent low mood
- a loss of pleasure or interest in normal everyday activities
- irritability
- feelings of despair, guilt and worthlessness
- feeling lethargic or sleepy during the day
- changes to sleeping patterns (e.g. sleeping longer than normal or struggling to get up in the morning)
- changes to appetite
- difficulty concentrating
Therefore, it is important to support our wellbeing over the winter months wherever possible. This includes incorporating regular exercise, getting exposure to daylight, eating a balanced diet, getting a good night’s sleep [link to sleep article: https://thomasfranks.com/newsarticles/the-importance-of-sleep-for-mental-health/] and managing feelings of stress.
You could try:
- Building a better night time sleep routine
- Taking part in a new sport or activity with a friend
- Going for a daily walk in the sunlight
- Adding more variety to your diet
- Journalling about your day
As always, if you are experiencing any concerns or have noticed changes to your mental health, seek additional support from your GP.
References
- Głąbska D, Kołota A, Lachowicz K, Skolmowska D, Stachoń M, Guzek D. (2021) The Influence of Vitamin D Intake and Status on Mental Health in Children: A Systematic Review. Nutrients. 13(3).
- Eyles DW, Smith S, Kinobe R, Hewison M, McGrath JJ. (2005) Distribution of the vitamin D receptor and 1 alpha-hydroxylase in human brain. Journal of Chemical Neuroanatomy. 29, pages 21–30.
- Patrick RP, Ames BN. (2015) Vitamin D and the omega-3 fatty acids control serotonin synthesis and action, part 2: relevance for ADHD, bipolar disorder, schizophrenia, and impulsive behavior. FASEB J. 29(6), pages 2207-22.
- Jenkins, Trisha A., Jason C. D. Nguyen, Kate E. Polglaze, and Paul P. Bertrand. (2016) Influence of Tryptophan and Serotonin on Mood and Cognition with a Possible Role of the Gut-Brain Axis. Nutrients. 8(1), page 56.
- Glatt DU, McSorley E, Pourshahidi LK, Revuelta Iniesta R, McCluskey J, Beggan L, Slevin M, Gleeson N, Cobice DF, Dobbin S, Magee PJ. (2022) Vitamin D Status and Health Outcomes in School Children in Northern Ireland: Year One Results from the D-VinCHI Study. Nutrients. 14(4), page 804.
