Seasonal Affective Disorder: who to see and what helps

Seasonal Affective Disorder · Kitchener, Waterloo & Cambridge

Seasonal affective disorder (SAD) is depression that returns in the same season each year, for most people in fall and winter, and lifts in spring. Canada’s depression guideline recommends bright light therapy as a first-line treatment for winter depression, while the UK’s guideline calls the evidence for it uncertain; both positions are set out below. CARESPACE’s counsellors are Registered Psychotherapists and Registered Social Workers, and one of them is the first person to see.

What seasonal affective disorder is

SAD is not a separate diagnosis. It is major depression, or sometimes bipolar disorder, that follows the calendar: episodes that begin and end at about the same time each year, for at least two years in a row. In the usual pattern symptoms start in late fall or early winter, last four or five months, and go away in spring and summer.

It is more common in people who live far from the equator, where winter days are short. In Waterloo Region the shortest day of the year, December 21, has about nine hours of daylight, against about fifteen and a half in June, and from late November the sun is down before 5 p.m.

A 2020 review for family physicians in the United States gives a lifetime prevalence of 0.5% to 2.4% in the general population, and says 10% to 20% of people with major depression have a seasonal pattern. SAD occurs much more often in women, and often begins in young adulthood.

The symptoms are those of depression. What sets SAD apart is the timing, and a tilt toward sleeping and eating more.

Symptoms of SAD

• Low mood
• Losing interest in things you usually enjoy
• Feeling guilty, hopeless or worthless
• Feeling restless or irritable
• Difficulty concentrating
• Being more tired and sleeping more than usual
• Being hungrier and eating more than usual, often with a craving for carbohydrates and weight gain
• Pulling back from people, a feeling of wanting to hibernate
• Thoughts of suicide or self-harm

A less common summer pattern looks different: irritability, poor appetite with weight loss, trouble sleeping and agitation.

What causes SAD

It is thought to be linked to the reduced daylight of winter, acting on the body’s daily sleep rhythm and on brain chemicals such as melatonin and serotonin. A family history of SAD or depression raises the risk, and the risk falls with age.

How SAD is diagnosed

A physician or nurse practitioner can assess and diagnose SAD, using the criteria for depression plus the seasonal pattern, not a screening questionnaire. A seasonal pattern can belong to bipolar disorder as well as to depression, which is one reason the diagnosis is a medical one. Registered Psychotherapists and Registered Social Workers provide counselling and do not diagnose or prescribe.

When it is urgent

Thoughts of suicide or self-harm are among the symptoms of SAD, and they should always be taken seriously.

If you are thinking about suicide, or you do not feel safe, do not wait for an appointment: use the numbers below.

If you are in crisis or thinking about suicide, help is available right now.

• Call or text 9-8-8, the Suicide Crisis Helpline, at any hour.
• Call Here 24/7 at 1-844-437-3247 for addictions, mental health and crisis services in Waterloo Region, at any hour. here247.ca
• Call 911 or go to the nearest emergency department if you or someone else is in immediate danger.

The emergency departments in Waterloo Region are:

• WRHN @ Midtown (formerly Grand River Hospital), 835 King St. W., Kitchener
• WRHN @ Queen’s Blvd. (formerly St. Mary’s General Hospital), 911 Queen’s Blvd., Kitchener
• Cambridge Memorial Hospital, 700 Coronation Blvd., Cambridge

If you cannot get there safely, call 911.

What the evidence says about treating SAD

• Who says what. Canada’s 2023 depression guideline (CANMAT), the UK’s 2022 depression guideline (NICE), two Cochrane reviews of prevention, and the 2020 US review. In the Canadian guideline, “first-line” means good trial evidence plus clinical support; the label reflects the panel’s confidence, not only the trials.
• Light therapy: the guidelines disagree. The Canadian guideline continues to recommend light therapy as a first-line treatment on its own for winter depression, and the US review rates it effective. NICE says people who want to try it in preference to antidepressants or psychological treatment should be advised that the evidence for its efficacy is uncertain.
• How it is used. The Canadian protocol is 10,000 lux of white light for 30 minutes a day in the morning, shortly after waking. The US National Institute of Mental Health describes daily use from fall to spring.
• Check before you start. Light therapy is considered very low risk, and side effects such as nausea, headache and eye strain are usually mild. The NHS in the UK says to speak to a doctor first all the same, which here means a physician or nurse practitioner: it may not be suitable if you have certain eye conditions or take medicines that increase sensitivity to light.
• CBT works, and may last longer. The US review rates cognitive behavioural therapy effective for SAD as well. In two trials that compared it with light therapy, remission was similar after the first winter; by the second winter the CBT group had fewer recurrences and more remissions.
• Antidepressants. SSRIs may play a role, on low-quality evidence; antidepressants usually take four to eight weeks to work. For prevention, a Cochrane review of 3 trials in 1,100 people found that bupropion XL, started before winter, reduced recurrences (moderate-certainty evidence), with more headaches, insomnia and nausea. Its authors caution that even among people at high risk, three out of four will not benefit.
• Preventing it with light. A second Cochrane review found a single trial of 46 people and rated the evidence very low certainty: too limited to say.
• Exercise, ideally outdoors. For depression in general, the Canadian guideline recommends supervised exercise as a first-line treatment on its own when depression is mild and as a second-line addition when it is moderate. NICE advises that any regular physical activity could help wellbeing, and that the benefits can be greater outdoors. For SAD itself, well-designed trials of exercise are lacking.

How CARESPACE helps with SAD

Counselling & Psychotherapy

CBT adapted for SAD has two parts. One works on the thoughts that come with the season, such as thoughts about the darkness of winter. The other, behavioural activation, means identifying and scheduling pleasant, engaging activities, indoors and out, to offset the loss of interest that winter brings. It is typically run as two group sessions a week for six weeks. If your pattern is predictable, book for early fall: people with a history of SAD may benefit from starting treatment before the season does. When you book, ask whether a counsellor who offers CBT for depression is available.

See our counselling team →

More about cognitive behavioural therapy (CBT) →

Nurse Practitioner

A Nurse Practitioner can make the diagnosis, advise whether light therapy is suitable with your eyes and your medicines, and prescribe and monitor an antidepressant, including one started ahead of winter where that makes sense.

See our nurse practitioner team →

Personal Training

The exercise recommended for mild depression is specific: supervised, low to moderate intensity, 30 to 40 minutes at a time, three or four times a week, for at least nine weeks. A personal trainer can set that program up and supervise the sessions. Treat it as an addition to treatment for SAD: the trials behind the recommendation were in depression generally.

See our personal training team →

Other services people ask about

Naturopathic medicine. The two guidelines disagree about St John’s wort, and neither statement is about SAD in particular. The Canadian guideline recommends it as a first-line treatment for mild depressive episodes and second-line for moderate ones, with two cautions of its own: an uncertain risk of serotonin syndrome when it is combined with an SSRI or SNRI antidepressant, and a risk of drug interactions, which it calls an important consideration because St John’s wort is sold over the counter. NICE says clinicians should not prescribe it or advise its use, because of uncertainty about doses and lasting effect, variation between preparations, and potentially serious interactions with other drugs, including hormonal contraceptives, anticoagulants and anticonvulsants. Talk to a pharmacist, physician or nurse practitioner first. Vitamin D is covered in the questions below.

Nutrition. A bigger appetite, carbohydrate cravings and weight gain are symptoms of winter SAD, but none of the sources tested a dietitian’s care for it. For depression in general there is a single trial, showing a modest effect of a Mediterranean-type diet, which supports only a third-line recommendation.

Where most people start

With a counsellor, ideally before your usual dip. See a physician or nurse practitioner first if the pattern has never been assessed, if you are thinking about an antidepressant, or if you want to use a light box and have an eye condition or take regular medicines.

How your team works together

SAD can involve three people: a counsellor for CBT, a prescriber for the diagnosis, the light therapy check and any medication, and a trainer for the exercise program.

Browse by service: counselling, nurse practitioner and personal training.

What to expect at your first visit

The first visit, with a counsellor, goes better if you bring:

1. Your calendar. The month it usually starts, the month it lifts, and how many winters it has happened.
2. What changes. Sleep, appetite, weight, energy, and how much you see people.
3. Treatments so far. A light box (how bright, what time of day, how long), medication, exercise, supplements.
4. What your winter days look like. Work hours, a commute in the dark, time outdoors.

You leave the first visit with a plan.

What you can do at home

The NHS in the UK lists this self-care for SAD:

• Get as much natural daylight as you can, and go outside in the daytime every day.
• Exercise regularly.
• Stay in contact with friends and family.
• Keep up your usual activities.
• Go to bed and get up at the same time every day.
• Do not drink too much alcohol or use illegal drugs.
• Put screens away before bed.

In a Waterloo Region December the daylight is gone by the end of the workday, so for anyone with a day job the first item means the lunch hour.

Outlook

Winter-pattern SAD goes away in spring and summer, and it tends to return at about the same time the next year. Once it has come back, long-term or preventive treatment is typically indicated.

Seasonal affective disorder treatment in Kitchener, Waterloo and Cambridge

Kitchener. Counselling in Kitchener and Personal Training in Kitchener. Locations: Victoria North, Fischer-Hallman, Westmount East and Deer Ridge.

Waterloo. Counselling in Waterloo and Personal Training in Waterloo. Locations: Weber North, Uptown Waterloo and Waterloo GoodLife.

Cambridge. Counselling in Cambridge. Location: Hespeler Road.

The city pages linked above show the locations and practitioners for each service, with their next availability.

Common questions

Do SAD lamps work?

It depends which guideline you ask. Canada’s makes light therapy a first-line treatment for winter depression. The UK’s calls the evidence uncertain, and the NHS does not usually provide it for that reason, though it notes that many people find it helps.

What should I look for in a light box?

Brightness of 10,000 lux, the standard the NHS in the UK names and the Canadian protocol uses, and a lamp that is UV-free.

Does vitamin D help with SAD?

The evidence is inconclusive. Vitamin D has not been well studied in SAD, and the results are mixed: some studies found it as effective as light therapy and others found no effect. It can interact with some medicines, so mention it to your prescriber or pharmacist.

When should I start treatment?

Before your usual season, if you have a history of SAD: the US National Institute of Mental Health suggests starting before the fall, and the bupropion trials began between September and November.

How short are winter days in Kitchener-Waterloo?

On the shortest day, December 21, Waterloo Region gets about nine hours of daylight (9 hours 4 minutes in SunriseSunset.io’s table for 2026). The earliest sunset, 4:49 p.m., comes on December 9. The longest day, in June, has 15 hours 33 minutes.

Do I need a referral?

No. Book online or call 519-208-2273. You pay at each visit and receive a receipt for your extended health plan. More on fees and insurance →

Sources

• Lam RW, Kennedy SH, Adams C, et al. Canadian Network for Mood and Anxiety Treatments (CANMAT) 2023 Update on Clinical Guidelines for Management of Major Depressive Disorder in Adults. Canadian Journal of Psychiatry, 2024.
• National Institute for Health and Care Excellence (UK). Depression in adults: treatment and management (NG222), 2022.
• Nussbaumer-Streit B, Forneris CA, Morgan LC, et al. Light therapy for preventing seasonal affective disorder. Cochrane Database of Systematic Reviews, 2019 (summary only).
• Gartlehner G, Nussbaumer-Streit B, Gaynes BN, et al. Second-generation antidepressants for preventing seasonal affective disorder in adults. Cochrane Database of Systematic Reviews, 2019 (summary only).
• Galima SV, Vogel SR, Kowalski AW. Seasonal Affective Disorder: Common Questions and Answers. American Family Physician, 2020.
• National Institute of Mental Health (US). Seasonal Affective Disorder, revised 2023.
• NHS (UK). Seasonal affective disorder (SAD), reviewed December 2025.
• Centre for Addiction and Mental Health (CAMH). Seasonal Affective Disorder.
• SunriseSunset.io. Regional Municipality of Waterloo, ON: sunrise and sunset times, viewed November 2026.
• 9-8-8: Suicide Crisis Helpline. 988.ca.
• Here 24/7 (addictions, mental health and crisis services, Waterloo Wellington). here247.ca.

Related conditions

• Depression
• Insomnia
• Stress

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Book online with a counsellor, or call 519-208-2273 and our Central Reception Team will match you with the right person and the closest location.

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