‘Mother Nature thinks people should shut down’: why we’re so unmotivated in winter

One dark and dreary February, I was bemoaning my lack of motivation. My therapist said this was perfectly normal.

“I just want to stay inside under a blanket in the winter,” she said. It didn’t bother her because she knew that, come spring, she would feel more motivated. This was actually quite a productive insight for me, so maybe she wasn’t giving her winter abilities enough credit.

Winter sluggishness is common, especially the farther you get from the equator, as temperatures and daylight hours vary more from winter to summer. “Most people – nine out of 10 – feel better in the summer to some extent,” says Dr Paul Desan, director of the Winter Depression Research Clinic at Yale.

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But why exactly does winter make so many of us feel drained and unmotivated? And how do we deal with this? We asked experts.

Why do some people feel less motivated during winter?

The wiring that controls human moods is not fully understood, but a certain amount of sluggishness in the winter makes sense from an evolutionary perspective, says Desan.

“Obviously Mother Nature thinks people should shut down for the winter if they live far from the equator,” he says. “If you’re a hunter-gatherer, you’re probably better off just eating a lot and staying home and resting [in winter].” Then, when temperatures warm, days lengthen and resources are more plentiful, our energy returns.

The sun also has a powerful effect on our hormones, explains Dr Jessica Jackson, a licensed psychologist and the vice-president of alliance development for Mental Health America. “When you’re getting less daylight in the winter months, that affects your serotonin levels, which then causes you to have a lower mood,” she says.

How do you know if your winter blues are seasonal affective disorder (Sad)?

Feeling low energy in the winter is common. But how do you know if it’s something more serious?

“For some people, the seasonal change is major,” says Desan. “It shuts down their life, and affects their ability to work and their concentration.”

People who have seasonal affective disorder experience an episode of clinical depression at roughly the same time every year, says Desan. This can manifest as a lower mood, lower energy, lower motivation, and sleeping and eating more than usual. For those with Sad, these episodes usually last from October or November through January or February, and then improve as the sun comes back in the spring.

Sad affects roughly 5% of adults in the US, according to the American Psychiatric Association, and about 3% of adults in the UK, according to the Royal College of Psychologists.

Anywhere from 10-15% of adults might experience subsyndromal seasonal affective disorder, says Desan. This includes those who don’t meet the criteria for clinical depression, but who experience low energy and motivation in the winter.

“They say: ‘I don’t get anything done in the winter, I have to push myself to go to work, and I withdraw from my hobbies,’” explains Desan. “Maybe they don’t have a full [depressive] episode, but it still really affects people.”

Doesn’t the heat sap energy too?

Is winter really so much more draining than summer? As anyone who has sweated through a heatwave knows, high temperatures can also leave you feeling cranky and depleted.

Heat can “impair cognition, worsen emotional states, increase aggression, disrupt brain networks needed for attention, lead to worse sleep, harm decision-making ability and exacerbate symptoms of mental illness”, says Dr Kim Meidenbauer, assistant professor in Washington State University’s department of psychology and Health Equity Research Center.

Thermoregulation – the process by which our bodies try to keep their core temperature within a healthy range – is a “metabolically costly process”, says Meidenbauer. This leaves less energy for thinking clearly and paying attention.

Both cold and hot temperatures can affect our ability to think and focus, but our responses tend to be different. “Cold will slow people’s responses, while heat will speed them up,” says Meidenbauer. High temperatures, therefore, can lead to greater impulsivity, while cold temperatures generally do not.

How do you treat the winter blues?

The first guard against seasonal mood changes is awareness, says Jackson. If you know you tend to feel lethargic in the winter, try building a routine you can stick to, even when you want nothing more than to burrow into your couch. Maybe you usually go to the gym before work, for example, but in the winter it feels better to go after work.

Related: ‘Big light has no vibe’: why you should ditch overhead lighting

Light therapy – exposing yourself to bright light, meaning 10,000 lux (the unit of illumination) or more, for half an hour every morning – has also been found to successfully treat both Sad and subsyndromal Sad. “It’s miraculous for a lot of people,” says Desan.

Standard light therapy treatment is to expose yourself to 10,000 lux for 30 minutes every morning using a special light box. “You can set up one of these devices, and use it while you eat breakfast and read the paper,” says Desan.

Light therapy lamps are easy to find, but not all are created equal, warns Desan.

“There’s a lot of garbage out there that’s too small or too dim,” he says. “It might be 10,000 lux, but that’s only if you put your eyes against it and don’t move.”

Effective light therapy lamps are bright enough that you can sit at arm’s length from them and still experience the benefits.

Experts say that if your mental health deteriorates significantly during the winter, make sure to see a mental health professional “who can do an assessment and identify all the factors that might be relevant”, says Desan.