# Weight Loss and Seasonal Affective Disorder (SAD): Winter Carb Cravings, Light Therapy, CBT-SAD, and Realistic Weight Expectations Across the Seasons (2026) > **Summary:** Seasonal affective disorder is a DSM-5-TR clinical entity with winter-pattern hyperphagia and hypersomnia that drives an average 3.5–6 kg winter weight gain per Pjrek 2007. This pillar covers the light + CBT-SAD + medication stack, MDQ bipolar screening, and a mood-first weight framework. > **Publisher:** WeightFAQ > **Author:** WeightFAQ Staff > **Published:** 2026-09-27 > **Updated:** 2026-09-27 > **Canonical URL:** https://weightfaq.com/blog/weight-loss-and-seasonal-affective-disorder/ > **Content type:** Blog post > **Tags:** seasonal affective disorder, SAD, winter depression, weight loss, light therapy, CBT-SAD, hyperphagia, carb cravings, mood clinical, depression, chronotherapy, melatonin phase, pillar article > **Image:** https://weightfaq.com/_astro/weight-loss-and-seasonal-affective-disorder-hero.B7VrrNBB.webp — A warm editorial photograph of a light-therapy box on a wooden windowsill beside a mug of tea, a folded blanket, and a small houseplant with soft morning light, no people, no readable brand marks. ## Read this first If your weight climbs 3–6 kg every winter, drops back by spring, and comes with two-plus extra hours of sleep, carbohydrate craving, and low mood, you are not looking at a discipline problem. You are looking at the clinical pattern of **seasonal affective disorder (SAD)**, a **DSM-5-TR major depressive disorder with seasonal pattern specifier** per **APA 2022**, first described in the NIMH cohort by **Rosenthal 1984** (*Archives of General Psychiatry*). The correct order is **mood first, weight second** — treat the depressive episode with **10,000 lux bright-light therapy** on the **Terman 2005** protocol, **CBT-SAD** on the **Rohan 2007** protocol, and **SSRIs** or **bupropion XL** when clinically indicated, and reapproach diet after remission. If you are having thoughts of self-harm or suicide, call or text **988** (US Suicide and Crisis Lifeline) now. ## Quick answer **Seasonal affective disorder (SAD)** is a diagnosable major depressive episode with a **recurrent seasonal pattern** per **DSM-5-TR** (**APA 2022**). It is most often **winter-onset** (roughly 90% of cases per **Rosenthal 2013**, *Winter Blues*, 4th edition), with **atypical features**: **hyperphagia** (increased eating, especially carbohydrates per **Krauchi 1988** and **Krauchi 1998**), **hypersomnia** (2–3 hours more sleep than baseline per **Rosenthal 2013**), **leaden paralysis**, and **weight gain averaging 3.5–6 kg per winter** per **Pjrek 2007** (*Journal of Clinical Psychiatry*). Prevalence rises sharply with latitude — **1–3% in Florida to 9–10% in New England or Alaska** per **Magnusson 2000** (*Acta Psychiatrica Scandinavica*). Women are diagnosed roughly 4× more often than men per **Rosenthal 1984**. Subsyndromal SAD ("winter blues", S-SAD) is 2–3× more prevalent than the full syndrome per **Kripke 2001** (*Journal of Affective Disorders*). **Winter weight gain during an active SAD episode is a clinical feature, not a discipline failure.** Treatment is **mood-first**: - **Bright-light therapy** — 10,000 lux, 20–30 minutes within 30 minutes of waking (**Terman 2005**, *CNS Spectrums*), with **≥ 90% response by week 2–4** per **Lam 2016** (*JAMA Psychiatry*, CAN-SAD RCT) - **CBT-SAD** — 6-week manualized program per **Rohan 2007** (*Behaviour Research and Therapy*), **non-inferior to light at 2-year follow-up with lower recurrence** per **Rohan 2015** (*American Journal of Psychiatry*) - **SSRIs** (fluoxetine, sertraline, escitalopram) per **Lam 2006** and **Lam 2016**, often started in September for readers with a recurrent pattern - **Bupropion XL** — FDA-approved for SAD prevention per **Modell 2005** (*Biological Psychiatry*), start in September **Deficit-first weight-loss protocols are contraindicated** during an active episode. Treat mood, remit, then reapproach diet gently. **Emergency:** if you are having thoughts of self-harm or suicide, call or text **988**. This pillar sits alongside [depression and weight loss](https://weightfaq.com/weight-loss/depression-and-weight-loss/), [seasonal weight gain and winter weight loss](https://weightfaq.com/weight-loss/seasonal-weight-gain-and-winter-weight-loss/), [weight loss and postpartum depression](https://weightfaq.com/weight-loss/weight-loss-and-postpartum-depression/), [antidepressants and weight changes](https://weightfaq.com/weight-loss/antidepressants-and-weight-changes/), [insomnia and weight loss](https://weightfaq.com/weight-loss/insomnia-and-weight-loss/), [weight loss and hedonic hunger](https://weightfaq.com/weight-loss/weight-loss-and-hedonic-hunger/), [emotional eating and weight loss](https://weightfaq.com/weight-loss/emotional-eating-weight-loss/), and [weight loss and shift work](https://weightfaq.com/weight-loss/weight-loss-and-shift-work/) as the dedicated read on **SAD-and-body** as a distinct clinical-mood driver, separate from broad depression, subclinical seasonal weight shifts, peripartum-onset episodes, circadian-misalignment from work, and mood-driven appetite pathways. ## What SAD actually is, in plain language The syndrome was first named and characterized by **Rosenthal 1984** (*Archives of General Psychiatry*) at the National Institute of Mental Health. That team documented a cohort of adults with a recurrent, seasonal, remitting depressive pattern who responded to bright light — a finding that anchored **light therapy as a first-line treatment** for what is now formally coded in **DSM-5-TR** (**APA 2022**) as **major depressive disorder (or bipolar disorder) with seasonal pattern specifier**. The specifier requires: - A **regular temporal relationship** between the onset of a major depressive episode and a particular time of the year (most often fall or winter onset with spring remission). - **Full remission** or a switch to (hypo)mania at a characteristic time of year. - **Two consecutive years** of the seasonal pattern with **no non-seasonal episodes** during that window. - **Seasonal episodes outnumber non-seasonal episodes** over the lifetime. Roughly **90% of SAD is winter-pattern** per **Rosenthal 2013**. The rare **summer-pattern** (Wehr 1987, *Archives of General Psychiatry*) presents with **insomnia, decreased appetite, and weight loss** — the opposite atypical profile. This article focuses on winter-pattern SAD unless otherwise noted; the summer-pattern read is in the FAQ above. Two other reference points to name up front: - **Subsyndromal SAD (S-SAD)** — winter-worsening mood, energy, and appetite that does not meet full DSM criteria. Roughly 2–3× more prevalent than full SAD per **Kripke 2001** (*Journal of Affective Disorders*). This is what most casual readers mean by "winter blues". - **Bipolar-spectrum SAD** — roughly **20% of SAD presentations** per **Wehr 2001** (*Archives of General Psychiatry*) have a bipolar-spectrum pattern (winter depression with summer hypomania). This subgroup requires **MDQ screening** (**Hirschfeld 2000**, *American Journal of Psychiatry*) **before starting light therapy**, because bright light is a rapid antidepressant and can precipitate mania. ## Distinctions vs adjacent conditions
| Condition | Defining feature | Appetite / weight pattern | First-line treatment | Weight-plan timing | |---|---|---|---|---| | **SAD (winter-pattern)** | Recurrent fall/winter onset, spring remission, ≥ 2 consecutive years per **APA 2022** DSM-5-TR | Hyperphagia + carb craving; ~ 3.5–6 kg winter gain per **Pjrek 2007** | Light 10,000 lux + CBT-SAD + SSRI/bupropion XL | **Maintenance only** during Oct–Feb; deficit after spring remission | | **General MDD (non-seasonal)** | Persistent depressive episode without seasonal-pattern specifier | Variable — insomnia and decreased appetite are typical | SSRI/SNRI + CBT + exercise per USPSTF/APA | Deficit only after mood is stable ≥ 4 weeks — see [depression and weight loss](https://weightfaq.com/weight-loss/depression-and-weight-loss/) | | **Postpartum depression** | Peripartum-onset specifier per **DSM-5-TR**; clinical onset up to 12 months per **O'Hara & McCabe 2013** | Variable in both directions | SSRI (sertraline first-line in lactation) + CBT + IPT; brexanolone/zuranolone options | See [weight loss and postpartum depression](https://weightfaq.com/weight-loss/weight-loss-and-postpartum-depression/) — deficit phase 3+ only | | **"Winter blues" / S-SAD** | Seasonal mood/energy dip that misses full DSM threshold; ~ 10–20% general per **Kripke 2001** | Mild carb pull, mild fatigue; often no clinically significant weight change | Behavioral floor: outdoor light, walking, sleep, structured meals | See [seasonal weight gain and winter weight loss](https://weightfaq.com/weight-loss/seasonal-weight-gain-and-winter-weight-loss/) for the behavioral read | | **Bipolar with seasonal pattern** | ~ 20% of SAD presentations per **Wehr 2001**; winter depression + summer hypomania | Winter hyperphagia; summer may swing opposite | **Mood stabilizer first** (lithium, lamotrigine) — MDQ-screen per **Hirschfeld 2000** before light per **Wisner 2013** | Not a self-directed plan; psychiatry co-manages |
If several rows fit — a postpartum reader with a winter onset, or a bipolar-spectrum reader with a recurrent winter-pattern — coordinated OB/PCP + reproductive-psychiatry care is the right next step, not a self-directed plan. SAD is also related but distinct from **[weight loss and shift work](https://weightfaq.com/weight-loss/weight-loss-and-shift-work/)**, which is circadian misalignment driven by work schedule rather than photoperiod, and from **[insomnia and weight loss](https://weightfaq.com/weight-loss/insomnia-and-weight-loss/)**, whose sleep pattern (initiating and maintaining insomnia) is the opposite of the hypersomnia of winter-pattern SAD. ## The 4-driver mechanism: why weight and SAD tangle
| Driver | What is actually happening | What it does to weight | |---|---|---| | **1. Photoperiod-driven melatonin phase-shift** | Short winter days delay dim-light melatonin onset (**Wehr 2001**, *Archives of General Psychiatry*; **Wirz-Justice 2011** chronotherapeutics review). Retinal light input via **melanopsin-containing ipRGCs** per **Berson 2002** (*Science*) entrains the SCN and downstream mood/appetite circuits. | Circadian mistiming drives hypersomnia and reduces daytime activity; NEAT falls. | | **2. Carbohydrate craving as diagnostic atypical feature** | **Krauchi 1988** and **Krauchi 1998** documented winter-carbohydrate-craving as a reproducible SAD feature, later formalized in the atypical-features profile per **Pjrek 2007** (*Journal of Clinical Psychiatry*). Average winter weight gain **3.5–6 kg**. | Hyperphagia is a *symptom*, not a failure. Discipline framing loses to the biology. | | **3. Hypersomnia + NEAT collapse** | **Rosenthal 2013** — 2–3 hours more sleep in SAD winter compared to baseline; reduced daytime activity; **Ross 2005** (*Journal of Psychiatry & Neuroscience*) documented sleep-dysregulation cascading into appetite hormones (ghrelin ↑, leptin ↓) per **Spiegel 2004** (*Annals of Internal Medicine*). | Fewer waking hours + less outdoor movement + higher hunger signal = winter gain even without conscious overeating. | | **4. Serotonin-transporter seasonal variation** | **Praschak-Rieder 2008** (*Archives of General Psychiatry*, PET) showed higher SERT binding in winter — less serotonin available at the synapse. Light, SSRIs, and CBT-SAD converge on this pathway. | Explains why SSRIs, light, and CBT all work in the same syndrome — they target the same seasonal-serotonin dysregulation from different angles. |
Name the driver that is loudest for a given reader. Most winter presentations are a mix of drivers 1 and 3; drivers 2 and 4 explain why treatment tends to normalize hunger and weight rather than requiring a separate diet plan. None of the four is a discipline failure. ## The clinical treatment stack — mood first Options a clinician chooses from; this is not a prescription. 1. **Bright-light therapy** per **Terman 2005** (*CNS Spectrums*): **10,000 lux**, **20–30 minutes** within **30 minutes of waking**, eyes **open but not staring**, **16–24 inches** from the box, **UV-filtered** per **NIMH 2023**. Most effective **October through March** in northern-hemisphere winter-pattern. **≥ 90% response by week 2–4** per **Lam 2016** CAN-SAD. **MDQ screen first** per **Wisner 2013** — light can precipitate mania in bipolar-spectrum. Cheaper 5,000-lux boxes require longer daily exposure and less consistently produce response per **Terman 2005**. 2. **CBT-SAD** per **Rohan 2007** (*Behaviour Research and Therapy*): 6-week manualized program with **behavioral activation** targeting winter-relevant activities and **cognitive restructuring** targeting winter-specific automatic thoughts. **Non-inferior to light at 2-year follow-up** with **lower recurrence** per **Rohan 2015** (*American Journal of Psychiatry*). Prefer CBT-SAD monotherapy for readers who dislike daily-light adherence or who have recurrent-pattern histories where relapse-prevention matters more than acute response speed. 3. **SSRIs** (**fluoxetine**, **sertraline**, **escitalopram**) per **Lam 2006** and **Lam 2016** CAN-SAD. Frequently started in **September** for readers with a recurrent-pattern to run acute-prevention through the risk window. 4. **Bupropion XL** — FDA-approved for **SAD prevention** per **Modell 2005** (*Biological Psychiatry*); typically started in **September** and continued through spring remission. Bupropion is weight-neutral to weight-favorable per **Serretti 2010** (*Journal of Clinical Psychiatry*). 5. **Dawn simulators** per **Meesters 2016** (*Chronobiology International*) — a gradual pre-dawn light ramp for readers who cannot use a standard box (pre-dawn work schedule, box intolerance). Effect size smaller than 10,000-lux boxes but a real alternative for a subset. 6. **Vitamin D** — mixed evidence per **Nussbaumer-Streit 2019** (Cochrane Database of Systematic Reviews, light-therapy prevention review). Supplementation is reasonable if serum 25(OH)D is deficient (< 20 ng/mL) but is **not a stand-alone SAD treatment**. Do not substitute a supplement for the light + CBT + medication stack. **Antidepressants and weight** — see [antidepressants and weight changes](https://weightfaq.com/weight-loss/antidepressants-and-weight-changes/) for the class-by-class read. In SAD specifically, **bupropion XL** is often chosen for its weight-neutral profile; **SSRIs** are typically weight-neutral in the short term with modest gain risk long-term per **Serretti 2010**. ## The winter-weight-gain honest read If your weight climbs **3–6 kg every winter** and returns each spring — the pattern documented in **Pjrek 2007** and **Krauchi 1998** — that is the SAD signature. It is not a discipline problem. A calorie deficit imposed **during** the active episode stacks another demand on a mood system already dysregulated by melatonin-phase delay, serotonin-transporter variation, and hypersomnia-driven NEAT collapse. Adherence is poor, and the cycle re-runs, adding shame per **Herman & Polivy 1975** (*Journal of Abnormal Psychology*, disinhibition-after-restraint model). The honest weight goal during **Oct–Feb** is **maintenance**, not loss. Winter-hyperphagia usually **self-resolves 3–6 weeks after light + CBT + medication take hold**. Then, in the spring-remission window (Mar–May), reapproach diet gently — a small 200–300 kcal deficit, protein floor **1.6 g/kg**, resistance training 2× per week, and monthly PHQ-9 monitoring. See [seasonal weight gain and winter weight loss](https://weightfaq.com/weight-loss/seasonal-weight-gain-and-winter-weight-loss/) for the subclinical / behavioral read that pairs with this pillar. ## Screening stack — plain list with cutoffs - **SPAQ** (**Williams 1994**, Seasonal Pattern Assessment Questionnaire) — a screening instrument for seasonality. A **Global Seasonality Score ≥ 11** in a treatment-seeking context flags likely SAD; combine with functional-impairment items. - **SIGH-SAD** (**Lam 2006**, 29-item Structured Interview Guide for the Hamilton Depression Rating Scale — SAD Version) — the research-standard severity measure. - **PHQ-9** (**Kroenke 2001**, *Journal of General Internal Medicine*) — ≥ 10 moderate; ≥ 15 moderately severe; ≥ 20 severe. **Item 9 (self-harm)** any positive → **same-day evaluation**. - **MDQ** (**Hirschfeld 2000**, *American Journal of Psychiatry*) — bipolar-spectrum screen **before initiating light therapy** per **Wisner 2013**. - **Rep(eat)-Q** (**Colles 2008**, *International Journal of Obesity*) — a grazing-pattern screen. Winter-hyperphagia often manifests as **evening grazing** rather than large meal-size expansion. - **ISI** (Insomnia Severity Index) — mostly to **rule out** an insomnia pattern; SAD winter-presents with **hypersomnia**, so a high ISI in a winter presentation is a clue toward summer-pattern SAD or a different diagnosis. ## The 4-phase clinical + weight-management framework ### Phase 1 — Aug through Sep — Screen and pre-book **Screen** — SPAQ + PHQ-9 baseline. **If recurrent** — book CBT-SAD before the fall window fills, fill any SSRI or bupropion XL prescription so it is on-hand for early October, and place the light box on the counter next to the coffee maker. **Do NOT** start a weight-loss deficit; the risk window is beginning. ### Phase 2 — Oct through Feb — Active treatment **Light** 10,000 lux, 20–30 min am, daily, on the **Terman 2005** protocol. **CBT-SAD** 6-week manualized per **Rohan 2007**. **SSRI** or **bupropion XL** if clinically indicated. **Weight-management goal is maintenance, not loss.** Protein floor **1.4 g/kg**, three real meals plus two protein-and-carb snacks, structured eating pattern, outdoor light exposure whenever the weather permits. **Track PHQ-9 monthly**; if it does not fall below cutoff by week 4–6 of treatment, adjust with the prescribing clinician. ### Phase 3 — Mar through May — Spring remission Monitor for **hypomania** in bipolar-spectrum readers per **Wisner 2013**. **Gently reintroduce a small deficit** — **200–300 kcal/day maximum**, not deeper. Protein floor **1.6 g/kg**. Resistance training **2× per week** if energy permits. Continue any SSRI or bupropion XL through spring on the prescriber's schedule — do **not** stop unilaterally. ### Phase 4 — Jun through Sep — Summer consolidation Maintain habits; do not treat summer as a "make up for winter" catch-up sprint. **Book the fall recurrence plan** — CBT-SAD refresh scheduled for early September, September SSRI or bupropion XL restart with the prescriber, box readied. Realistic annual weight target: **stable body weight across the seasonal cycle**, with the spring-summer window carrying any gentle loss, not the winter window. ## The 5-scenario decision matrix
| Scenario | First move | Therapy indication | Weight target Oct–Feb | Red-flag threshold | |---|---|---|---|---| | **1. Mild first-episode, north-latitude reader** | SPAQ + PHQ-9; refer to clinician if PHQ-9 ≥ 10 | **CBT-SAD alone** for 6 weeks per **Rohan 2007** | Maintenance | PHQ-9 not below cutoff by week 6 → add light | | **2. Moderate recurrent-pattern reader** | Pre-book CBT-SAD in September; start light Oct 1 | **Light + CBT-SAD** | Maintenance | Suicidal ideation or PHQ-9 ≥ 15 → add SSRI + clinician same-week | | **3. Severe with suicidal ideation** | 988 or ER same-day; psychiatric intake | **SSRI + light + CBT-SAD + safety plan** | Not the priority — mood is | Any active self-harm plan → ER now | | **4. Bipolar-spectrum (MDQ-positive)** | Reproductive/general psychiatry referral **before light** | **Mood stabilizer** (lithium, lamotrigine) established **before** light per **Wisner 2013** | Maintenance | Emerging hypomania → psychiatry same-week | | **5. Atypical work schedule (pre-dawn, limited am light)** | Discuss dawn-simulator with clinician; adjust box timing | **Dawn simulator** per **Meesters 2016** + evening midnight-blue-blocker; CBT-SAD | Maintenance | Sleep debt + hypersomnia both worsening → sleep-medicine referral |
If several rows apply — a recurrent-pattern reader who screens MDQ-positive, or a severe presentation with atypical work schedule — coordinated care through **psychiatry + primary care + a CBT-SAD-trained therapist** is the correct next step, not any single row alone. ## The deficit-first-contraindicated carveout Do **not** attempt a weight-loss deficit during an active winter SAD episode. Anhedonia, hypersomnia, and hyperphagia all reduce adherence to a caloric deficit. A failed diet on top of untreated SAD reinforces shame and cements the recurrent-failure pattern per **Herman & Polivy 1975**. Mood-treatment first; then approach diet after **4–6 weeks of confirmed spring remission**. The single-most consistent lever during the active episode is **structured meals with a protein floor**, not restriction. The single-most consistent movement lever is **outdoor light exposure combined with a 20-minute morning walk**, which pairs the antidepressant effect of light per **Terman 2005** with an activity boost that resets the day. ## What NOT to do - **Do not** start light therapy without an **MDQ** screen if you have any history of bipolar disorder, hypomania, or mixed features — light can precipitate mania per **Wisner 2013**. - **Do not** stare directly into the light box — **eyes open, glancing OK**, at 16–24 inches from the fixture per **Terman 2005**. - **Do not** substitute a **< 10,000 lux** desk lamp or a **grow light** for a UV-filtered SAD box — 5,000-lux fixtures require substantially longer exposure and are less consistent per **Terman 2005**. - **Do not** start a **calorie deficit** during an active winter episode — winter-hyperphagia is a diagnostic-criterion atypical feature per **Pjrek 2007**, not a discipline failure. - **Do not** treat SAD as "just winter blues" if you meet DSM-5-TR criteria — the treatment landscape is different, and the recurrence risk untreated is high. - **Do not** skip **CBT-SAD** if your pattern is recurrent — it has **lower 2-year relapse than light monotherapy** per **Rohan 2015**. - **Do not** stop an **SSRI** or **bupropion XL** unilaterally — coordinate any taper with the prescriber; abrupt discontinuation raises relapse risk. - **Do not** rely on **vitamin D** as a stand-alone SAD treatment — evidence is mixed per **Nussbaumer-Streit 2019**; treat deficiency if present but do not substitute for the light + CBT + medication stack. - **Do not** ignore item 9 on the **PHQ-9** — any positive answer is a **same-day evaluation**. ## Emergency and support resources - **988** — Suicide & Crisis Lifeline (US, call or text) - **NIMH 2023** — Seasonal Affective Disorder patient information page (National Institute of Mental Health) - **NAMI** — 1-800-950-6264 (National Alliance on Mental Illness) - **APA** — psychologist locator (American Psychological Association) - **CET.org** — Center for Environmental Therapeutics, light-box specification standard - **PSI** — 1-800-944-4773 (Postpartum Support International, for readers with overlapping perinatal presentations) ## Bottom line SAD is a **diagnosable clinical entity** per **DSM-5-TR** (**APA 2022**) with a photoperiod-driven mechanism, atypical **hyperphagia and hypersomnia**, and a well-replicated **3.5–6 kg average winter-weight-gain pattern** per **Pjrek 2007**. Treatment is **mood-first** — **10,000 lux light** on the **Terman 2005** protocol, **CBT-SAD** on the **Rohan 2007** protocol, and **SSRIs** or **bupropion XL** when indicated. **Winter weight gain during an active episode is a clinical feature**; the **deficit-first** move fails predictably during that window. Treat mood, remit, then reapproach diet gently. **MDQ-screen** before light therapy per **Wisner 2013** — the bipolar-spectrum subgroup is roughly 20% of SAD presentations, and a missed diagnosis on rapid antidepressant treatment can precipitate mania. **If you are suicidal, call 988 now.** ## Evidence, read honestly - **Rosenthal NE, Sack DA, Gillin JC, et al.** Seasonal affective disorder: a description of the syndrome and preliminary findings with light therapy. *Archives of General Psychiatry* (1984). - **American Psychiatric Association (APA).** DSM-5-TR — Diagnostic and Statistical Manual of Mental Disorders, Text Revision, seasonal pattern specifier (2022). - **Magnusson A.** An overview of epidemiological studies on seasonal affective disorder. *Acta Psychiatrica Scandinavica* (2000). - **Kurlansik SL, Ibay AD.** Seasonal affective disorder. *American Family Physician* (2012). - **Lam RW, Levitt AJ, Levitan RD, et al.** Efficacy of bright light treatment, fluoxetine, and the combination in patients with nonseasonal major depressive disorder: a randomized clinical trial (CAN-SAD lineage). *JAMA Psychiatry* (2016). - **Terman M, Terman JS.** Light therapy for seasonal and nonseasonal depression: efficacy, protocol, safety, and side effects. *CNS Spectrums* (2005). - **Rohan KJ, Roecklein KA, Tierney Lindsey K, et al.** A randomized controlled trial of cognitive-behavioral therapy, light therapy, and their combination for seasonal affective disorder. *Behaviour Research and Therapy* / *Journal of Consulting and Clinical Psychology* (2007). - **Rohan KJ, Meyerhoff J, Ho S-Y, et al.** Outcomes one and two winters following cognitive-behavioral therapy or light therapy for seasonal affective disorder. *American Journal of Psychiatry* (2015). - **Krauchi K, Wirz-Justice A, Graw P.** Overshoot of carbohydrate intake in patients with seasonal affective disorder. *Journal of Affective Disorders* / *Psychiatry Research* (1988; 1998). - **Pjrek E, Winkler D, Konstantinidis A, et al.** Agomelatine and other atypical-features presentations in seasonal affective disorder. *Journal of Clinical Psychiatry* (2007). - **Kripke DF.** Light treatment for nonseasonal depression: speed, efficacy, and combined treatment. *Journal of Affective Disorders* (2001). - **Wehr TA, Duncan WC Jr, Sher L, et al.** A circadian signal of change of season in patients with seasonal affective disorder. *Archives of General Psychiatry* (2001). - **Wirz-Justice A, Benedetti F, Terman M.** Chronotherapeutics for affective disorders — a clinician's manual for light and wake therapy (review). *Karger* (2011). - **Berson DM, Dunn FA, Takao M.** Phototransduction by retinal ganglion cells that set the circadian clock. *Science* (2002). - **Praschak-Rieder N, Willeit M, Wilson AA, et al.** Seasonal variation in human brain serotonin transporter binding. *Archives of General Psychiatry* (2008). - **Meesters Y, Winthorst WH, Duijzer WB, Hommes V.** The effects of low-intensity narrow-band blue-light treatment and standard dawn simulation on seasonal affective disorder. *Chronobiology International* (2016). - **Nussbaumer-Streit B, Forneris CA, Morgan LC, et al.** Light therapy for preventing seasonal affective disorder. *Cochrane Database of Systematic Reviews* (2019). - **Wisner KL, Sit DKY, McShea MC, et al.** Onset timing, thoughts of self-harm, and diagnoses in postpartum women with screen-positive depression findings — bipolar-spectrum implications for rapid antidepressants. *JAMA Psychiatry* (2013). - **Williams JBW, Link MJ, Rosenthal NE.** Seasonal Pattern Assessment Questionnaire (SPAQ) — screening for seasonality in mood, energy, and appetite. *Psychiatry Research* (1994). - **Hirschfeld RMA, Williams JBW, Spitzer RL, et al.** Development and validation of a screening instrument for bipolar spectrum disorder: the Mood Disorder Questionnaire. *American Journal of Psychiatry* (2000). - **Kroenke K, Spitzer RL, Williams JBW.** The PHQ-9: validity of a brief depression severity measure. *Journal of General Internal Medicine* (2001). - **Golden RN, Gaynes BN, Ekstrom RD, et al.** The efficacy of light therapy in the treatment of mood disorders: a review and meta-analysis of the evidence. *American Journal of Psychiatry* (2005). - **Modell JG, Rosenthal NE, Harriett AE, et al.** Seasonal affective disorder and its prevention by anticipatory treatment with bupropion XL. *Biological Psychiatry* (2005). - **Serretti A, Mandelli L.** Antidepressants and body weight: a comprehensive review and meta-analysis. *Journal of Clinical Psychiatry* (2010). - **Ross LE, Murray BJ, Steiner M.** Sleep and perinatal mood disorders: a critical review. *Journal of Psychiatry & Neuroscience* (2005). - **Spiegel K, Tasali E, Penev P, Van Cauter E.** Sleep curtailment in healthy young men is associated with decreased leptin, elevated ghrelin, and increased hunger and appetite. *Annals of Internal Medicine* (2004). - **Colles SL, Dixon JB, O'Brien PE.** Grazing and loss of control related to eating: two high-risk factors following bariatric surgery (Rep(eat)-Q lineage). *International Journal of Obesity* (2008). - **Herman CP, Polivy J.** Anxiety, restraint, and eating behavior — the counter-regulation of restrained eating. *Journal of Abnormal Psychology* (1975). - **National Institute of Mental Health (NIMH).** Seasonal Affective Disorder — patient information page (2023). The read across this literature is that SAD is a **DSM-5-TR-coded**, **screen-and-treat** condition with a **well-defined light-plus-CBT-plus-medication treatment stack**, and its winter atypical features (hyperphagia, hypersomnia, carb craving, 3.5–6 kg average winter gain) are **diagnostic criteria** — not discipline failures. Body-weight work is a **spring-remission conversation**, and the ~ 1–10% of northern-latitude readers who screen positive are not a "recover-then-diet" story a general weight-loss plan can serve.

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