With the clocks going back an hour in the Western part of the world, the days are getting shorter and the nights longer. The weather is getting cooler and winter is just round the corner. With all of this the general mood for most of us changes. Feeling down, having a lack of drive, a lack of energy and a general low mood are common symptoms for most. It's a rather dramatic shift from the summer where the mood is one of general happiness, fun and energy is abundant. These are classic signs that you maybe suffering from seasonal affective disorder (SAD).
Seasonal affective disorder (SAD) is a type of depression that comes and goes in a seasonal pattern. SAD is sometimes known as "winter depression" because the symptoms are more apparent and tend to be more severe during the winter. The symptoms often begin in the autumn as the days start getting shorter. They're typically most severe during December, January and February. SAD often improves and disappears in the spring and summer, although it may return each autumn and winter in a repetitive pattern .
Symptoms of SAD can include :
For some people, these symptoms can be severe and have a significant impact on their day-to-day activities.
The specific cause of seasonal affective disorder remains unknown. Some factors that may come into play include :
It's clear that the change in light patterns plays an important role in SAD. With less daylight and for those who work in offices, hospitals, labs and generally where the light is artificial all day and no light when work is finished, the effects of SAD can be more present. Let us discuss the science behind this to understand why it can affect us.
Vitamin D is essential for humans for survival. It is made when sunlight hits the skin. I won’t go into the science behind this, just take my word for it (and read my Vitamin D blog). With a lack of sunlight, vitamin D synthesis is limited. Numerous studies have suggested the condition may be triggered by lack of sunlight. SAD is more common among people who live at high latitudes or areas with lots of cloud .
One hypothesis behind SAD is that reduced sunlight exposure interferes with the body's biological clock that regulates mood, sleep and hormones. Another theory is that lack of sunlight causes an imbalance of neurotransmitters - such as dopamine and serotonin - which regulate mood .
A research team led by Alan Stewart of the College of Education at the University of Georgia - published their findings in the journal Medical Hypotheses:
"We hypothesize that rather than functioning primarily as a proximal or direct sub-mechanism in the etiology of SAD, vitamin D likely functions in a more foundational and regulative role in potentiating the sub-mechanisms associated with the depressive and seasonality factors," say the researchers.
Firstly, the researchers note that vitamin D levels in the body fluctuate with the changing seasons in response to available sunlight. "For example," says Stewart, "studies show there is a lag of about 8 weeks between the peak in intensity of ultraviolet (UV) radiation and the onset of SAD, and this correlates with the time it takes for UV radiation to be processed by the body into vitamin D."
Co-author Michael Kimlin, of the Queensland University of Technology in Australia, says that vitamin D also plays a part in the synthesis of both dopamine and serotonin, noting that past research has associated low levels of these neurotransmitters with depression.
"Therefore," he adds, "it is logical that there may be a relationship between low levels of vitamin D and depressive symptoms. Studies have also found depressed patients commonly had lower levels of vitamin D."
The researchers also believe there is a link between skin pigmentation and vitamin D levels, which may affect an individual's risk for SAD. They explain that studies have shown that people with darker skin pigmentation are at greater risk of vitamin D deficiency, and if such individuals relocate to high-latitude regions, they may have a higher chance of developing SAD .
So why are serotonin and dopamine so important for us?
Serotonin is one of the most important neurotransmitters (chemicals used by brain cells to communicate with each other). Serotonin exhibits a wide range of functions in both the brain and the body, especially of the central nervous system and the gastrointestinal tract .
The first known function of serotonin was controlling blood vessel constriction. But it is much better known as the “happy molecule” for the important role it plays in positive mood. Most brain cells are affected directly or indirectly by serotonin where it regulates mood, social behaviour, libido, sleep, memory, and learning. The advent of prescription antidepressants like Prozac and Zoloft turned serotonin into a household word .
These drugs are selective serotonin re-uptake inhibitors (SSRIs) which are believed to work by increasing serotonin levels. While serotonin is almost always associated with brain function, mood, and mental well-being, surprisingly 95% of our serotonin is manufactured in the intestines, not the brain .
In fact, this “second brain” in our gut contains 100 million neurons, more than in either the spinal cord or the peripheral nervous system. Researchers are still unclear as to why there is so much serotonin activity in the intestines. It seems that serotonin facilitates communication between the gut and the brain, but serotonin used by the brain must be produced there since serotonin created in the gut is unable to pass through the brain’s protective filter. Because so much serotonin resides outside of the brain, some experts consider serotonin a hormone as well as a neurotransmitter .
Dopamine is a neurotransmitter released by the brain that plays a number of roles in humans and other animals. Some of its notable functions are in :
Dopamine is the chemical that mediates pleasure in the brain. It is released during pleasurable situations and stimulates one to seek out the pleasurable activity or occupation. This means food, sex, and several drugs of abuse are also stimulants of dopamine release in the brain, particularly in areas such as the nucleus accumbens and prefrontal cortex .
Deficient levels of dopamine activity in the brain can cause depression. this dopamine deficient depression (DDD) is characterised by a low energy, demotivated state, as opposed to the intensely painful character of serotonin deficient depression (SDD). A severely dopamine deficient depressed person may wish they were dead, but wouldn’t have the motivation or energy to do anything about it. The tortured, antsy serotonin deficient depressed person is a much higher risk of suicide. Suddenly increasing energy and motivation in a person with DDD by boosting dopamine can temporarily increase suicide risk. This is also a known and common side effect with antidepressant drugs .
Dopamine gives the brain energy, motivation, a switched on feeling and excitement about new ideas. A surge in dopamine can give a high and pleasurable feeling. The increased energy and talkativeness a coffee can cause is mainly due to the effect of increased dopamine levels. If you’ve ever felt sluggish first thing in the morning or afternoon for example and found a coffee gave you mental energy, sharpness and renewed enthusiasm that was a dopamine boost. (1-2 coffees a day gives you multiple health benefits by the way).
Dopamine is the primary neurotransmitter involved in the feeling of pleasure, feeling high and euphoric. Dopamine is involved in the pursuit of pleasure. It is often said that anything you do that feels really good has just given your dopamine levels a boost.
To little dopamine can also cause: depression coupled with significant fatigue, real apathy, maybe slowed thinking, drowsiness, the inability to feel enthusiastic about anything, no motivation and excessive sleep. It can also be involved in ADD/ADHD .
Both dopamine and serotonin elevate one's psychological mood producing an antidepressant effect. Serotonin primarily influences feelings of happiness, optimism, contentedness, seeing the cup half-full so to speak. Dopamine on the other hand influences feelings of, excitement, pleasure, euphoria, which can be addictive, dopamine gives one the feeling of reward that creates motivation and drive .
In a single word serotonin gives us happiness, dopamine gives us pleasure.
It is very clear to see that a lack of vitamin D can do so much to our bodies physically, mentally and emotionally. A lack of vitamin D will affect our serotonin and dopamine levels. Due to this it is clear that we feel more low during the winter months.
Now that we know what can causes seasonal affective disorder, what can be done to tackle this disorder? Below is a few quick and easy wins that can be done :
Investing in a vitamin D lamp could also be wise. Whilst these is no scientific proof, or rather studies to prove this works, there’s no evidence to say that it doesn’t work! So it could be worth purchasing one and keeping it on when working in low light conditions. Note when you have this lamp on, try and keep your head and arms (at a minimum) naked to absorb the light.
During the winter months, take a vitamin D supplement. Vitamin D content in foods is limited, therefore taking a vitamin D supplement during the winter months is vital for your health and wellbeing. In addition to vitamin D helping your hormones, it is vital for your immune system, which is helpful during the winter months where colds and flus are abundant.
You have read above about serotonin and how it is the ‘second brain’. There is so much serotonin activity in our intestines, it is vital we feed our body the right foods that will help our intestines keep a healthy level of serotonin creation for the brain. Here are some foods that will help with that :
Lastly, if by changing your lifestyle and diet you still feel that you are suffering from SAD, it could be that you need professional help from a psychiatrist or other therapies such as cognitive behavioural therapy (CBT).
CBT is based on the concept that your thoughts, feelings, physical sensations and actions are interconnected, and that negative thoughts and feelings can trap you in a vicious cycle. CBT aims to help you deal with overwhelming problems in a more positive way by breaking them down into smaller parts. You're shown how to change these negative patterns to improve the way you feel. Unlike some other talking treatments, CBT deals with your current problems, rather than focusing on issues from your past. It looks for practical ways to improve your state of mind on a daily basis .
The important thing is to seek help and do something if you feel you have symptoms of SAD or a generally feeling low and underwhelmed all year round, regardless of the seasons.
If you feel you require support with a change of mood and lifestyle in the winter or require general guidance on nutritional support and how to live a balanced lifestyle please contact me at firstname.lastname@example.org or visit my website by going to www.urbanplatehealth.com