Winter brings shorter days and less light. For many, it signals the onset of seasonal affective disorder. Diet, exercise, and light therapy may help improve our mood.
When winter brings about long, frosty nights, cold toes, and pink noses, it’s not uncommon for Canadians to lament the change in season. Fifteen percent of Canadians find that their moods are affected by dreary winter weather, and about two to three percent are thought to suffer from seasonal affective disorder (SAD).
Seasonal affective disorder is a type of depression that occurs during a certain time of year—most commonly during the long, cold winter months. However, SAD may make the summer months the most hated season for some, as a small but significant minority of people with the condition suffer instead from the aptly named summer SAD, which is not well understood.
Causes
While the cause of this syndrome isn’t currently known, research indicates that two neurotransmitters, serotonin and melatonin, may play a role in the disorder’s onset.
Serotonin, the “feel good” hormone, helps regulate our moods. Low levels of light—including those brought on by dreary seasons with short days and long nights—are associated with lower levels of serotonin in our bodies. As serotonin levels lower, so does our mood.
And just as low light levels are linked to a decrease in serotonin levels, they cause an increase in melatonin, the hormone that saps our energy and helps us fall asleep at night. “SAD sufferers may produce more melatonin at night and into the early morning,” explains Jennifer Bunzenmeyer, a naturopathic doctor in Calgary. “Therefore, this can leave people feeling lethargic through the day.”
Those living in northern countries are at an increased risk of developing SAD. Women are more commonly affected than men.
Negative life experiences, such as moving, losing a family member, or getting into a car accident, and having weak social systems are also associated with an increased risk of SAD, as is having a close family member with the disorder.
Symptoms
SAD may be difficult to differentiate from other forms of depression because of the number of symptoms these various forms share. Common symptoms include
However, there are a few symptoms that are found most often in those suffering from SAD. The biggest indicator is the period during which these symptoms take place. They work on a cycle, appearing and then disappearing during specific seasons.
Winter SAD generally brings about an increased desire to sleep; increased appetite causing weight gain; and intense cravings for pastas, sweets, or other foods high in carbohydrates, while summer SAD normally causes difficulty sleeping and decreased appetite leading to weight loss.
Treatment
Fortunately, there’s no need to muddle through the offending seasons, as treatment options do exist.
Conventional antidepressants such as selective serotonin reuptake inhibitors (SSRIs) have been shown to be effective, but may not be for everyone due to their numerous side effects.
Light therapy
For those who would prefer to stay away from conventional medications, light therapy has been shown to be just as effective as antidepressants for managing SAD symptoms with only minimal, if any side effects. For instance, some people find that light therapy too close to bedtime can interfere with sleep.
This form of treatment may take place in two forms: bright light therapy and dawn simulation.
Bright light therapy, as its name implies, involves exposing a patient to extremely bright lights, normally measuring 10,000 lux, for 30 minutes or more per day (a sunny day is about 50,000 lux).
Dawn simulation, meanwhile, uses longer exposure times of up to 90 minutes and gradually brightening lights to imitate a natural sunrise. Light exposure with dawn simulation takes place while the patient is sleeping.
Light therapy devices are commercially available. Ask your health care practitioner for advice on where to find one near you.
While researchers aren’t entirely sure why light therapy works, they believe that it resets our internal clocks. Bright light exposure has also been shown in some studies to increase our levels of serotonin while decreasing our levels of melatonin.
Negative air ions
Negative ions—atoms that have gained an extra electron—have long been recognized for having a positive effect on our moods. Naturally, they’re created by sunlight, and by moving air and water. However, they can also be created in devices known as negative ion generators.
Not all ion therapies are equal, though. One study has found that, while nearly half of SAD sufferers subjected to high-density ions showed significant signs of improvement, only about 23 percent of those exposed to low-density ions had similar relief.
Diet and exercise
Eating a healthy diet is an important tool to help manage SAD symptoms. As Bunzenmeyer asserts, balanced meals rich in protein, complex carbohydrates, and healthy fats may help keep unpredictable blood sugar levels—and the unpredictable moods that may accompany them—at bay.
Exercise, meanwhile, can help relieve the stress that may build up as a result of SAD while reducing feelings of fatigue. Furthermore, studies have consistently shown that exercise may significantly improve the moods of those suffering from various forms of depression, including SAD.
Supplements
St. John’s wort
St. John’s wort is a thoroughly researched natural antidepressant and may help ease the symptoms of SAD. It works by affecting the brain’s uptake of serotonin, as well as two other mood-controlling chemicals, dopamine and norepinephrine. However, this herb can interact with many medications, so ask your health care practitioner to see if it’s right for you.
Rhodiola rosea
Rhodiola, often used to help those suffering from stress, has also been shown to be an effective treatment for mild to moderate depression.
Omega-3 fatty acids
Omega-3s, found in foods such as fish, flax, and nuts, may affect the way that serotonin works within the body. Animal research has shown that increasing the amount of omega-3s in the diet may help to correct imbalances caused by omega-3 deficiency.
Vitamin D
The active hormone in vitamin D, calcitriol, affects several mood-controlling factors in the body. A 2010 study involving 954 men and women over the age of 65 showed that those with low levels of vitamin D had a 72 percent chance of showing depressive symptoms. While some evidence hints that increased levels of vitamin D may help manage these symptoms, more research is needed to come to a definite conclusion.
B vitamins
Similarly, some B vitamins, such as vitamin B9 (folic acid), B6, and B12, may also plays a role in regulating our happiness. Once again, though, research is conflicted as to whether or not supplementing may help manage SAD and other forms of depression.
Anyone considering supplements or any other form of treatment for SAD—and anyone who thinks that they may be suffering from the disorder—should consult a professional health care practitioner.
See the light!
Lifestyle change—including getting as much natural sunlight as possible—is an important component for managing SAD symptoms. But during cold, blustery winter days, how can we get enough sunlight? Dr. Jennifer Bunzenmeyer offers these helpful tips:
Remember that every little bit helps. “If you have a business meeting or are meeting friends at a coffee shop, pick one that has windows so you can get exposure to light in your day. Eat your lunch at work in an area of the office that has light exposure,” says Bunzenmeyer.