Winter blues: understanding what is at play and taking action

Before taking action, it helps to distinguish two realities. The mild winter blues show up as more marked tiredness, lower motivation and sometimes increased irritability, without preventing day-to-day functioning. Seasonal affective disorder, a recognised season-linked form of depression, is more intense, more lasting and requires medical care. This distinction avoids both trivialising real suffering and medicalising a passing dip.

The reduction in hours of natural light alters the synchronisation of the circadian rhythm, with repercussions for perceived daytime energy and sleep quality. The cold also limits spontaneous outings, which mechanically reduces exposure to light and daily physical activity. These two effects often add up, amplifying the sense of fatigue as the weeks go by.

Winter isolation, encouraged by the cold and the drop in daylight that prompts people to stay at home, plays a bigger role in the seasonal dip in mood than is generally thought. Keeping up regular moments of exchange, even short ones — a phone call, a shared meal, a group activity — counterbalances this natural tendency to withdraw. This lever is often neglected in favour of more technical solutions, when it remains one of the most accessible day to day.

Winter remains a good season for root vegetables, vitamin C-rich citrus fruits and oily fish, a source of omega-3. A diet too heavily centred on sugary or ultra-processed products encourages swings in energy through the day, with dips in alertness that accentuate the sense of fatigue. Without aiming for a strict regime, favouring regular meals and seasonal produce remains a simple basis to keep to over time.

Regular physical activity supports both mood and sleep quality, two factors directly linked to the winter blues. A brisk 20 to 30-minute walk, taken outdoors as far as possible, combines the effect of movement with that of natural light, even under a cloudy sky. Regularity, rather than intensity, is what makes the difference over several weeks.

CBD is not a medicine and has no validated claim regarding mood in France. In case of persistent low spirits, consult a healthcare professional.

How do I know whether it is the winter blues or real depression?

The mild winter blues generally do not prevent day-to-day functioning and ease with adjustments to routine. Intense, lasting sadness, with marked withdrawal or a general loss of interest, requires medical advice.

Does a lack of vitamin D play a role?

Sun exposure decreases in winter, which reduces the skin's synthesis of vitamin D in many people. A blood test, prescribed by a doctor, makes it possible to assess whether supplementation is appropriate.

Should all social activity be avoided in winter if you lack energy?

On the contrary, keeping up regular social ties, even modest ones, helps counterbalance the natural winter tendency to withdraw and supports mood as the weeks go by.

At what point should you see a doctor?

As soon as the tiredness or sadness lasts several weeks, intensifies or disrupts sleep, work or relationships. A general practitioner remains the first relevant point of contact.

• Conseil d'État, interim order, 24 Jan. 2022, no. 460055 — primary
• Conseil d'État, 29 Dec. 2022, no. 444887 — primary
• Cour de cassation, criminal division, 14 Jan. 2025, series of judgments (24-81.076, 24-81.078, 24-81.365, 23-84.130, 23-85.359) — primary