With the changing of the season now is the time of year that some people can become aware of Seasonal Affective Disorder, sometimes called the winter blues. At the end of September we passed the autumn equinox, meaning that the days are once again shorter than the nights and as we head towards winter the weaker sunshine makes it less likely we will get the vitamin D we need.
What is Seasonal Affective Disorder (SAD)?
Seasonal Affective Disorder is a not a condition in its own right, but rather is seen as a recurring major depressive episode that occurs seasonally each year.
People affected will usually experience a range of symptoms including:
- Sad/Low Mood
- Lack of Energy
- Tired and Lethargic
- Difficultly Concentrating
- Reduced Activity
- Social Withdrawal
- Craving Carbohydrates
- Weight Gain
Depression of this type can also include thoughts of suicide and it is important if you are having persistent suicidal thoughts to see your GP urgently or call the Samaritans on 116 123 (Free).
People with seasonal affective disorder tend to show a decrease in the neurotransmitter Serotonin as daily sunlight diminishes. They may also have difficulty with overproduction of Melatonin. This hormone is produced by the pineal gland. This gland responds to darkness and the hormone causes sleepiness. As the winter days become darker, Melatonin production increases and in response people feel more sleepy and lethargic.
The combination of decreased Serotonin and increased Melatonin impacts our circadian rhythms – the body’s internal 24-hour clock. These rhythms are supposed to change in response to the light-dark changes that occur throughout the seasons. For people with SAD the circadian signal that indicates a seasonal change in day length has been found to be timed differently, thus making it more difficult them to adjust to the changing season.
Added to this is that we are likely to develop a deficiency in Vitamin D due to the weakening sunlight and that we tend to go out less at this time of year. Vitamin D is believed to play a role in serotonin activity and Vitamin D deficiency and insufficiency have been associated with clinically significant depressive symptoms.
Causal links between serotonin, melatonin, circadian rhythms, Vitamin D and SAD have not yet been confirmed, however, associations among these key factors are present and continue to be studied.
Some studies have shown that for some people anti-depressant medication of the SSRI (selective Serotonin reuptake inhibitor) type can be effective. However, a Cochrane review (often considered the gold standard in medical research) found insufficient evidence to support the use of these drugs for SAD and also noted that up to 27% of people treated with these drugs withdrew from studies early due to adverse side effects.
Light Therapy has consistently shown promise in reducing the impact of SAD. “they are best used in the morning and should be a broad-spectrum light that filters out ultraviolet rays. Typical exposure is 20 to 60 minutes of 10,000 lux of cool-white light. This is about 20 times greater than ordinary indoor lighting. Some people can experience headaches for the first few days. Light therapy should not be used in conjunction with photosensitising medications e.g. Lithium, Melatonin, Phenothiazine and certain antibiotics.
Vitamin D insufficiency has been shown to be associated with depression. Low levels are usually due to insufficient dietary intake or lifestyle issues, such as little exposure to outdoor sunshine. During the winter months of November to February people living 33 degrees north of the equator are not able to synthesise Vitamin D due to the lack of sunlight. For several years the NHS has recommended people consider a daily Vitamin D supplement during this time of year. https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
Counselling approaches can provide help and support to people with SAD. Cognitive Behaviour Therapy (CBT) has the goal of breaking down problems and negative thought patterns by changing the way people think about them. CBT can also help people improve their diet by limiting starches and sugars as well as increasing exercise, managing stress and avoiding social withdrawal. In addition to this various forms of meditation, such as Mindfulness and Yoga, have also been found to be beneficial. Other diet advice includes eating a protein rich diet (vitamin D is found in small amounts in oily fish and eggs), a diet free from processed foods and with complex carbohydrates.
SAD is a disorder precipitated by a lack of needed exposure to sunlight. The main focus of support should be to increase exposure to light, preferably sunlight, along with appropriate counselling, diet and Vitamin D supplement.