Is Blue Monday really the 'most depressing day' of the year? Here's what to know

This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis or treatment. Contact a qualified medical professional before engaging in any physical activity, or making any changes to your diet, medication or lifestyle.

January begins with so much promise. Although the holidays have come and gone, there's endless messaging of "new year, new me" as we make resolutions to be healthier and happier versions of ourselves.

But once the afterglow of the New Year wears off and we return to our day-to-day routines and wrestle with winter weather, many of us may feel our mood start to decline. But there's one day of the month — dubbed "Blue Monday" — that claims to be especially gloomy.

When is Blue Monday 2025?

Blue Monday falls on Jan. 20. It's supposedly the most depressing day of the year, which raises the question: Why did it earn that title in the first place?

What is Blue Monday?

There are plenty of reasons why January might be a depressing month. After all, you're coming off the joy and relaxation of the Christmas season, credit card statements from the holidays are rolling in and you might struggle to complete those New Year's resolutions. Combine that with long, dark and gloomy winter days, and you have a recipe for melancholy.

Blue Monday, which falls on the third Monday in January, sits right in the middle of this January depression. In fact, it's supposed to be one day of the year when people feel the most depressed.

Is Blue Monday real?

The good news is that there's no real evidence supporting the idea that Blue Monday exists. People might be feeling down in January, but there's no date when these feelings hit their peak.

What is scientifically proven is a shift in mood around the winter months. This is known as the "winter blues," a milder form of seasonal affective disorder (SAD). As many as 35 per cent of Canadians experience a downturn in their emotional state during the winter months.

Putting too much weight on a single day can have a harmful effect. Even if it's just a gimmick, Blue Monday's concept can influence how people feel. The belief in Blue Monday can be triggering for people who are already feeling down in January, especially if they're predisposed to depression.

How did Blue Monday start?

Unsurprisingly, Blue Monday has a pretty controversial origin. In 2005, British psychologist Dr. Cliff Arnall came up with the pseudoscientific theory that one day in January would be the year's most depressing day.

The catch? Dr. Arnall was paid by the travel firm Sky Travel to promote its holiday travel deals. It was all a marketing trick — a "scientific" phenomenon invented to push more vacation bookings in the month of January.

What to know about seasonal depression

While Blue Monday isn't a real phenomenon, you may have heard of something similar. Seasonal depression, or SAD (which stands for seasonal affective disorder), is a form of depression that might arrive or worsen around the winter months.

Changes in daylight and weather can trigger seasonal depression. That's why Canadians are especially at risk, thanks to the decreased sunlight of the long winter months. About 15 per cent of Canadians will report at least a mild case of SAD, with 2 to 5 per cent reporting more serious cases.

Here's what you need to know about this very real condition that's often mistaken for winter gloom:

Why people get seasonal depression

Experts aren't sure exactly what causes SAD, but the theory is that seasonal changes — including lack of sunlight — can upset your body's circadian rhythm. The lack of sunlight might cause problems with the way your body produces serotonin, the "happy" neurotransmitter that affects your mood.

Symptoms of seasonal depression

The list of SAD symptoms lines up with many of the symptoms of major depression. The main difference is that these symptoms tend to appear and disappear around the same time, usually in the winter.

The main symptom of seasonal depression is a change in mood that is present for most days, lasts for more than two weeks and impacts the way you live your life.

Other symptoms of seasonal depression include:

• Tiredness or low energy

• Loss of interest in things you used to enjoy

• Changes in appetite, including weight loss or gain

• Sleeping too much or too little

• Withdrawal from loved ones

• Difficulty participating in school, work or hobbies

• Feeling like the world is "slowed down"

• Irritability

• Difficulty concentrating or remembering

When it's time to seek help

It's not uncommon for people to feel down during the winter months. But depression isn't just "feeling sad" — it's a condition that can't be willed away. If you have any of the symptoms listed above, see a health care provider as soon as possible.

There are treatment options available for depression, including seasonal depression. These can include light therapy, exposure to sunlight, psychotherapy and antidepressants.

While your mood probably won't improve overnight, the right steps can help you feel better day by day. In addition to professional help, here are some things you can do on your own:

• Spend time with friends and family

• Talk about how you feel with others

• Do things that make you feel better, even if you don't have the motivation

• Get regular exercise

• Eat well-balanced meals

• Cut out habits like drinking and smoking

• Spend more time in the sunlight, if possible

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