Cold, dark days can lead to people seeking comfort in food and alcohol.
Days become a lot shorter, colder, and darker when we enter into late autumn. It gets even worse when the clocks go back an hour on October 29th.
The gloomy weather can make it harder for many people to get out of bed, be social, and exercise enough.
However, for some people it's more than just feeling a bit demotivated. According to the AAFP, 4-6% of people suffer from Seasonal Affective Disorder (SAD), also known as winter depression, which has symptoms such as a persistent low mood, irritability, feelings of despair and worthlessness, lethargy, comfort eating, and weight gain.
The National Health Service website says the most popular theory for SAD is that we don't get enough sunlight in the autumn and winter months, and this stops the hypothalamus working properly — the part of the brain responsible for hormones.
The brain may produce more melatonin than usual, which is the hormone that makes us feel sleepy. A lack of sunlight may also cause lower levels of serotonin, a happy hormone, meaning you may feel less motivated and energetic.
There are treatments for SAD, such as light therapy. However, if people aren't aware of these, or even the fact they have the disorder, some scientific evidence shows they could be at a higher risk of developing other problems, such as alcohol dependency.
One study from 2017, published in the journal European Psychiatry, looked at the behaviour of 4,880 Finnish participants, and found that those with SAD showed higher prevalence of alcohol disorders.
Lead author Isabel Morales, from the National Institute for Health and Welfare, Finland in Helsinki, told Business Insider that family studies suggest that there is a link between alcoholism and SAD, and genetic and environmental factors play a role in both.
Many studies have focused on serotonin and SAD, especially a particular gene that is responsible for the serotonin transporter. There have also been studies that look at the connection between this gene and alcoholism, finding that alcoholic patients have a higher frequency of a particular variant of the gene compared to nonalcoholic control participants.
"The ability of the serotonin transporter gene to affect both seasonality and alcohol use may be related to the anatomy and physiology of the brain’s serotonergic system," Morales told Business Insider. "Considerable evidence from animal and human studies suggest that serotonin is linked to different functions, such as mood, aggression, feeding, and sleep. Abnormalities of serotonergic function is believed to be involved in depression, impulsivity, and suicide."
She added that a dysfunction in releasing serotonin may be associated with behaviours relevant to develop alcoholism, such as a low response to alcohol intake.
"Furthermore, there may be a genetic link between seasonality and alcoholism," Morales said. "This relationship is complex and involves various factors."
For example, your personality type may predispose you to both seasonality and drinking too much. Also certain environmental and social factors during the colder months can contribute to developing SAD in alcoholic patients.
"For example, due to the colder climate in winter, people spend more time indoors where there is greater contact with alcohol and increased likelihood of drinking," she said. "To sum up, SAD may be a subtype of mood disorder that is closely related to alcoholism."
In the discussion of the studies, Morales and the other authors Seppo Koskinen and Timo Partonen note that SAD patients crave carbohydrates and sugars, and tend to gain weight from overeating.
"Given the well-established links between binge eating and addiction disorders, it is also suggested that seasonality, together with the same high-risk psychological profile, exacerbates the likelihood of engaging in a broad range of addictive behaviors, such as alcoholism," they write.
Seeking comfort in the winter months is normal, and when we consume more food it's usually just our bodies adjusting to the colder weather. However, if you feel there is something more going on, you can talk to your GP who may recommend some lifestyle measures, such as making sure you get as much natural sunlight as possible, exercising regularly, and managing your stress levels.
Light therapy and talking therapy are also available as treatment options, and antidepressants are sometimes offered if they are needed.