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Seasonal affective disorder: treatments and causes

The winter blues affect millions of adults worldwide. Prevent or treat seasonal affective disorder with these tips.

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October 25, 2021
6 min read

As the days get colder, darker, and shorter, you might notice a mood change in yourself or those around you. Perhaps you feel more fatigued, or sadder, or simply “low.” If so, you’re not on your own—seasonal affective disorder (SAD) affects millions of people around the globe every autumn and winter. 

And while you can’t control the changing seasons, you can change your lifestyle, your diet, and your supplements, so that you can experience more energy, joy, and optimism this winter.

Article breakdown

What is Seasonal Affective Disorder, and what are the symptoms?

Seasonal affective disorder is technically a type of seasonal disorder. Many people experience in a similar way that they might experience major depressive disorder (MDD), but the symptoms tend to be concentrated in the autumn and winter. For this reason, it’s often referred to as the winter blues or wintertime sadness. Summer depression also falls under the umbrella of SAD, but it’s much less common.

Symptoms of SAD include:

  • Feeling sad, moody and more teary than usual

  • Losing interest in the things you normally enjoy throughout the year

  • Craving comfort food, such as fatty foods, sugary foods, and carbohydrates

  • Experiencing sleep pattern changes, like sleeping too much or having trouble sleeping

  • Constantly feeling tired, fatigued, and low in energy

  • Being more irritable than usual

  • Experiencing brain health and cognitive changes, such as trouble focusing, making decisions, remembering things, or thinking clearly 

Some people experience just one or two of these symptoms, while others might experience all of them at once.

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How many people experience seasonal affective disorder each year?

Because SAD can manifest itself in ways that are very similar to other mood and seasonal disorders, many experts struggle to put a specific number on SAD statistics. 

Some experts believe that the number of people who experience true SAD could be as low as 0.5 percent

Others put this number much, much higher; with one study estimating that 4-6 percent of people have severe SAD, while an additional 20 percent have mild SAD.

Whatever the actual number, it’s clear that SAD is a global phenomenon that we must be equipped to face when struggling with winter depression.

Common causes, triggers, and risk factors of seasonal affective disorder

Everyone is susceptible to SAD, and scientists are still researching the exact causes of these mood changes. The general consensus is that it all comes down to sunlight exposure.

As we ease into the winter months, we’re exposed to less light. 

Since much of our circadian rhythm (sleep-wake cycle) and hormones are governed by the natural sunlight cycles, this decreased sunlight may negatively affect our brain chemicals and our sleep-wake cycle. For example, simply enjoying an afternoon out in the sun triggers a flood of serotonin (a feel-good brain chemical).

The opposite is also true: cold, dark days and nights correlate with lower levels of these positive brain chemicals, leading to a higher risk of seasonal depression.

And while everyone is susceptible to SAD, some people are at a higher risk. SAD rates tend to be higher among:

  • Women

  • Younger and middle-aged adults—SAD tends to appear most in your 20s and 30s, and becomes less frequent and severe as you age

  • People who live in the upper regions of the northern hemisphere

When to see a doctor about seasonal affective disorder

The NHS recommends seeing a medical professional if you have any of the symptoms of seasonal affective disorder. Your doctor may choose to do a psychological assessment to confirm a diagnosis, and can help you to evaluate how your lifestyle, diet, nutrition, and other daily practices relate to SAD.

It’s very important that all mental health concerns are always treated by a professional, as they are often interconnected with other mental health concerns. 

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Seasonal affective disorder (SAD) treatment: 3 ways to overcome SAD

There are three main SAD treatments:

  1. Light treatment and SAD light therapy for depression

  2. Regular exercise

  3. Diet and supplements

1. Light treatment and SAD light therapy for depression

Because of the link between lower sunlight exposure and higher rates of SAD, many doctors prescribe light therapy for SAD. Light therapy can take many forms: 

  • Light visors

  • Light boxes 

  • Scheduled time in the day to sit outside in the sun

In general, people report an elevated mood when they've exposed themselves to light therapy for at least 30 minutes a day throughout the autumn and winter. 

These special lights aren’t just your ordinary light bulbs. Rather, they mimic the full spectrum of the actual sun, helping to trigger the release of brain chemicals and reset your circadian rhythm.

You can take a look at the best lights for SAD here.

2. Regular exercise

Sweat out the effects of SAD, literally.

A regular exercise program is linked with significant reductions in SAD. This may be due to the way that exercise triggers the release of feel-good hormones, including serotonin. These hormones are great for combatting your winter depression.

For the best results, aim for 150 minutes of moderate aerobic activity every week. You don’t have to be a fitness buff to take part and enjoy the mood-enhancing benefits of physical movement:

  • Take your dog for a walk

  • Do yard work

  • Go for a walk with a friend

  • Try mindfulness movements, such as tai chi or yoga

  • Dance in your living room

  • Watch a home workout video

3. Diet and supplements

You are what you eat, and there are many healthy and delicious mood-boosting foods that can help to lift your spirits and combat your winter blues. Examples include:

Similarly, avoid excess sugar (which can trigger mood swings related to your blood sugar) and excess alcohol (alcohol is a depressant, and also sabotages your sleep-wake cycle). While sugar and alcohol are both in abundance during the winter, especially around the holiday season, moderation is your mood’s best friend. 

Beyond specific foods, nutrition intervention is one of the most proven seasonal affective disorder treatments. In general, researchers have shown that a diet filled with the following nutrients may make you more resilient against the effects of SAD: 

  • B vitamins 

  • Omega-3 polyunsaturated fatty acids 

  • Zinc 

  • Vitamin D

  • Antioxidants in general

However, many people struggle to get all of these vitamins, minerals, and antioxidants into their daily meals (particularly vitamin D).

That’s where supplements come in, giving you hope, support, and a path forward when you have the winter blues and need to combat your wintertime sadness.

Heights Smart Supplement bottle with blueberries, sugar snap and seeds
Heights Smart Supplement with blueberries and a snap pea
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The Heights Smart Supplement provides a full dose of nutrients that boost brain function, maintain a healthy mood, and look after your brain throughout the SAD season. With antioxidants and nutrients like blueberry extract, omega-3s, vitamin D, B vitamins, and zinc, the Smart Supplement can help you to combat all the symptoms of seasonal affective disorder (for example, sounder sleep, more energy, improved mood, and sharper focus).

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