There is something about fall that seems to make almost everyone happy.
The leaves begin to change. The mornings get crisp and cool. Sweaters come out of the closet. Football is on TV. Pumpkin-flavored everything appears overnight. We start thinking about cozy evenings, family gatherings and the holidays just around the corner. For many people, fall feels like a welcome change.
But for others, the change in seasons can bring something very different. As the days become shorter and sunlight becomes less abundant, some people notice changes in their energy, sleep, motivation and mood. They may feel more tired than usual, have difficulty getting going in the morning, want to sleep more, withdraw socially or simply feel a little “off.”
And there may be more going on than just a dislike of shorter days.
Your Body Notices When the Days Get Shorter
Our bodies are remarkably responsive to light. Throughout the year, the amount of daylight we receive changes. In the fall, sunrise comes later, sunset comes earlier and we naturally spend more time in darkness. That change in light exposure provides information to the brain about what time of day, and what time of year, it is.
One of the systems affected is our circadian rhythm, the approximately 24-hour internal clock that helps regulate sleep and wakefulness, hormone production, body temperature and other biological processes.
Light is one of the most important signals that keeps this internal clock synchronized with the outside world. When daylight decreases, that signal changes, and some people may have more difficulty adjusting. This is one of the big reasons many people who work third-shift jobs and sleep during the day have a huge biological adjustment to make.
For people who are particularly sensitive to seasonal changes, that adjustment can affect sleep, energy and mood. Research on seasonal affective disorder (SAD – an appropriate acronym) has identified circadian rhythm disruption as one of several biological factors that may contribute to seasonal depression.
Melatonin: Why You May Feel Sleepier
You’ve probably heard of melatonin, the hormone that helps regulate our sleep-wake cycle. Your brain naturally produces more melatonin when it gets dark, helping signal that it is time to sleep. As daylight decreases in the fall and winter, our bodies experience longer periods of darkness.
Research suggests that some people with winter-pattern SAD may produce melatonin for a longer period of time during the winter. That may contribute to increased sleepiness, fatigue and oversleeping. That doesn’t mean everyone who feels sleepy on a dark November morning has a melatonin problem. But it helps explain why the seasonal shift can feel surprisingly physical.
Your body isn’t simply saying, “I don’t feel like getting out of bed.” It may be responding to a genuine change in its environmental signals.
Serotonin and Seasonal Mood Changes
Another piece of the puzzle is serotonin, a neurotransmitter involved in regulating mood and other functions.
Research tells us people with winter-pattern SAD may have reduced serotonin activity during the darker months. Sunlight appears to influence biological mechanisms involved in maintaining serotonin activity, and shorter daylight periods may affect those mechanisms.
Researchers have also found seasonal differences in serotonin-related activity in people with SAD. It’s important to emphasize that this is more complicated than simply saying, “less sunlight equals less serotonin.” SAD is a complex disorder involving multiple biological, environmental and psychological factors. Researchers continue to study how serotonin, melatonin, circadian rhythms and other neurotransmitters interact.
What About Vitamin D?
Vitamin D is another factor that gets a lot of attention when the seasons change.
Our bodies can produce vitamin D when skin is exposed to sunlight. During the fall and winter, people generally spend less time outdoors and have less skin exposed to sunlight, which can make it more difficult for some people to maintain adequate vitamin D levels.
Low vitamin D levels are frequently found in people with winter-pattern SAD. However, that doesn’t necessarily mean vitamin D deficiency causes SAD, or that taking vitamin D will automatically prevent or treat seasonal depression.
Research on vitamin D supplements as a treatment for SAD has produced mixed results.
If you’re concerned about vitamin D, talk with your healthcare provider. A provider can determine whether testing or supplementation makes sense for you.
And there is one important misconception to clear up:
A tanning bed is not a good substitute for sunlight.
Although it seems logical to consider a tanning bed to replace lost sunlight, tanning beds expose the skin to ultraviolet (UV) radiation and increase the risk of skin cancer. They are not recommended as a way to obtain vitamin D. The American Academy of Dermatology recommends getting vitamin D through food and, when appropriate, supplements rather than intentional UV exposure. Prevention Magazine provides a list of foods high in Vitamin D.
If what you’re looking for is bright light for your brain, there is a much safer option.
Light Therapy: Replacing the Light Your Brain Is Missing
One of the most established treatments for winter-pattern SAD is bright light therapy. Light therapy uses a specially designed light box that provides bright light while filtering out potentially harmful UV radiation. A commonly recommended setup uses a 10,000-lux light box for roughly 20-45 minutes in the morning, although specific recommendations can vary.
The goal isn’t to tan your skin. It’s to give your eyes and brain a strong daylight-like signal at a time when natural daylight may be limited. For people experiencing SAD, light therapy can be an effective treatment. Anyone considering it, particularly people with certain eye conditions, medications that increase light sensitivity or bipolar disorder, should talk with their healthcare provider first.
So What Can You Do When Fall Makes You Feel “Off”?
The good news is that you don’t have to simply wait for spring. There are several practical ways to help your body and mind adjust to the changing season.
- Get Outside in the Morning
Even when it’s cold, cloudy or not particularly sunny, outdoor light is generally much brighter than typical indoor lighting. Try taking a morning walk, drinking your coffee on the porch, walking the dog or simply spending a few minutes outside after you wake up. Mayo Clinic recommends getting outside, particularly earlier in the day, as part of managing seasonal symptoms. And there’s a bonus: you’re moving your body at the same time.
- Consider a Light Box
If your schedule, location or weather makes it difficult to get enough morning light, a SAD-specific light box may be worth discussing with your healthcare provider. Look for a product designed specifically for SAD rather than a lamp intended for skin conditions. SAD light boxes are designed to provide bright visible light while filtering UV radiation. Think of it as giving your internal clock a little artificial sunrise.
- Keep Your Sleep Schedule Consistent
It can be tempting to sleep later, nap more or crawl into bed earlier when the days get darker. Try to avoid that temptation. Keeping relatively consistent wake and sleep times can help stabilize and maintain your circadian rhythm. Try to wake up at approximately the same time each day, avoid excessive napping and expose yourself to light early in the day. Your body likes consistency, even when the weather doesn’t provide it.
- Move Your Body
Exercise isn’t a cure for SAD, but physical activity can support mental and physical well-being and may help reduce stress and anxiety. Exercise is always a great idea anyway. Better yet, combine exercise with daylight. Take a walk through the neighborhood. Go apple picking. Rake leaves. Walk through a farmers’ market. Take the long way around the grocery store. Meet a friend for a walk instead of coffee.
The activity itself matters, but so does getting out of the house. Research on lifestyle interventions specifically for SAD is still limited, but studies have explored exercise, outdoor activity, sleep, nutrition and social engagement as possible supportive strategies.
- Give Your Brain Something to Look Forward To
Sometimes the best way to fight the seasonal slump is to intentionally create reasons to get up and get moving. Schedule a weekly lunch with a friend. Join a book club. Try a new class. Plan a fall day trip. Start a puzzle. Take up knitting. Learn a new recipe. Volunteer. Host a game night. Sign up for an exercise class. The possibilities are endless.
The idea is simple: don’t let your calendar become empty just because the days are getting shorter. This approach is consistent with behavioral activation, a component of cognitive behavioral therapy for SAD that encourages people to deliberately schedule enjoyable and engaging activities rather than waiting until they feel motivated to do them.
- Try a Mental “Light Switch”
Fall can sometimes bring a subtle shift in our thinking. It’s getting dark so early. Winter is coming. I don’t want to go anywhere. It’s too cold. I’ll do it when spring comes.
Those thoughts may seem harmless, but they can contribute to withdrawing from activities we normally enjoy. Cognitive behavioral therapy for SAD, or CBT-SAD, specifically addresses seasonal thought patterns and behaviors. Research suggests it can be effective for SAD, with some evidence that its benefits may continue into subsequent winters.
You don’t have to force yourself to “think positive.” Instead, try asking: What can I do today that will make today a little better? That question can be surprisingly powerful.
- Take Care of the Basics
Seasonal wellness doesn’t have to involve complicated solutions. It’s more important to keep it basic and consistent rather than trying trendy solutions. Simply eat regular, balanced meals. Stay hydrated. Keep moving. Get enough sleep. Spend time with people. Get outside. Maintain activities you enjoy. And pay attention to changes in your mood and energy. These habits may sound simple, but they give your body and brain a stable foundation while the environment around you is changing.
- Take a Trip to a Sunny Location
Sometimes easier said than done, but even a short trip away to a sunnier place can rejuvenate just about anyone’s body and soul. If you can do it, it’s a great solution as a pick-me-up!
When Is It More Than Just the “Winter Blues”?
It’s normal to have days when you feel tired, unmotivated or less energetic, especially when the weather is gloomy.
Seasonal affective disorder is different.
SAD is a type of depression with a recurring seasonal pattern. Symptoms can include persistent sadness, loss of interest in activities, low energy, changes in sleep or appetite, difficulty concentrating and social withdrawal. Winter-pattern SAD typically begins in late fall or early winter and improves during the spring and summer.
If changes in mood or energy last for more than a couple of weeks, interfere with everyday life or continue to get worse, it’s worth talking with your healthcare provider or a mental health professional.
Embrace Fall, But Listen to Your Body
There is nothing wrong with loving fall. In fact, there is plenty about it to love. But while you’re enjoying the changing leaves, cozy sweaters and your pumpkin latte, remember that your body is changing along with the season.
Less daylight can influence the biological systems that regulate sleep, circadian rhythms and mood. For some people, those changes are barely noticeable. For others, they can be significant.
The answer isn’t necessarily to fight the season. It may be to work with your biology.
So follow the solutions we’ve mentioned, even if you don’t have SAD or feel other seasonal changes. It’s always a good idea to keep moving, eat a balanced diet, get plenty of light and plenty of rest, and to stay connected.
Fall may bring a change in the weather. But with a little awareness, it doesn’t have to mean a change for the worse in how you feel.
Resources and further reading:
The Science Behind the Winter Blues (Pfizer)
Seasonal Affective Disorder (SAD) Symptoms & Causes (Mayo Clinic)
Seasonal Affective Disorder (Johns Hopkins Medicine)
12 Strategies to Deal with Seasonal Affective Disorder (Prevention)
