Understanding Seasonal Blues

Keep your mood from dropping in the fall

by Christiane Northrup, M.D.

Mood Issues & Stress

Exposure to light naturally increases feel good chemicals in our brains and bodies, such as serotonin. When the days shorten in the fall and you have less exposure to sun and natural light, you have a physiological setup for feeling a bit blue or moody.


This seasonal change isn’t in your imagination—seasonal affective disorder (SAD) is real and affects tens of thousands of people (maybe more) each year. As the summer ends, it’s not uncommon to experience fatigue, lethargy, weight gain, carbohydrate craving, excessive sadness, and changes in your libido. Luckily there are some easy things you can do to alleviate seasonal symptoms.

As the seasons change, you’re also more likely to experience premenstrual syndrome (PMS). And women with PMS are more likely to experience SAD. Let me share some insight on why your menstrual cycle is affected by the seasonal change. When light hits the retina, it directly influences the entire neuroendocrine system via the hypothalamus and the pineal gland. In one study, patients with PMS responded significantly to treatment with bright light. Their weight gain, depression, carbohydrate craving, social withdrawal, fatigue, and irritability were reversed with two hours of full-spectrum bright light in the evening. Parry¹ This is not surprising, because both natural light and carbohydrate consumption increase serotonin levels, which ease depression. Living under artificial light much of the time, without regular exposure to natural light, not only can profoundly affect the regularity of the menstrual cycle, but can also create PMS. Ott2 Kime3 Lieberman4 Rao5 Blundell6

The link between PMS and SAD is a profound example of how women’s wisdom is simultaneously encoded in both the cycle of the seasons and our monthly cycles. SAD is to the annual calendar as PMS is to the monthly cycle! The natural tendency to turn inward during the premenstrual time of our monthly cycle is reflected in the natural tendency to turn inward during the autumn of the year. All of nature reflects this wisdom back to us. In fall and winter, the trees send their energy down into their roots, where profound activity and revitalization go on even though it is not obvious to us. The early luteal phase of the menstrual cycle, following ovulation, is when our energies go deep into our roots so that we can take stock and then prepare for the next cycle of outer growth in the world. Because our culture doesn’t understand this cyclic wisdom, we have been taught to be afraid of both the times in our cycles and the seasons of the year when wisdom demands that we go into darkness, withdraw, and take stock of our lives.

We have been taught to be suspicious of these natural energies—and too many women see them as a weakness that needs to be overridden and ignored. Heaven forbid we should follow our body’s wisdom and take a break from getting it all done!

Chemical Changes

In the winter, we tend to make more melatonin. Melatonin is a natural substance created by the brain when it’s dark. And it aids with sleep. Too much melatonin can leave you feeling sluggish and mentally foggy. When you add this to the fact that our circadian rhythms, those that govern our sleep and wake cycle, are different in winter than in summer, it’s easy to understand why you might experience fatigue.

To counter this, you need to increase the amount of full spectrum light you are exposed to with full spectrum light bulbs and/or a light box. You will feel some relief from sleepiness and even premenstrual moodiness or irritability. All you need to do is expose yourself to regular doses of full spectrum light generated ambiently. Although light is absorbed by the eyes, you never stare at a light box or light bulb because it can cause eyestrain, headaches, and other symptoms. You just sit somewhere where the light reaches you out of the corner of your eye. Light boxes can be used during the day on a cloudy day, in the late afternoon, or early morning or evening to extend the day.

There are numerous studies that have demonstrated the connection between full spectrum light and serotonin levels. Willeit7 Interestingly, a drop in melatonin enhances feel-good hormones, including endorphins and serotonin, which help you feel both alert and calm. This transformation occurs in the brain as a result of being in more light. That’s why getting outside at noon for a half hour walk on a sunny day during the winter months will lift your mood greatly. Hold the sunglasses whenever possible. They block some of the colors of the light waves.

Help for Seasonal Blues

You can keep the seasonal changes from impacting you negatively by following these simple suggestions:

  • Take a pharmaceutical grade multi-vitamin/mineral every day. It’s essential to health!
  • Getting enough vitamin D is critical in winter months. I’ve written extensively about vitamin D, so I’ll just briefly mention that vitamin D levels drop in the winter because the body makes it after being exposed to sunlight. The vitamin D research is so compelling when it comes to the connection between depression and vitamin D deficiency. (Vitamin D deficiency is also linked to certain cancers, like breast and colon; a weakened immune system; poor bone health; and much more.) Make sure to get 1,000–4,000 IUs per day in the winter, especially if you tend to be vitamin D deficient (less than 32 ng/ml.).
  • In addition, make sure you’re getting enough essential fatty acids, which are found in coldwater fish (like salmon), nuts, seeds (like flaxseed), and many plants. Aim for 500–2,000 IUs of fish oil or flaxseed oil per day, or some combination of the two.
  • Eliminate refined sugar, refined flour, and other processed foods from your diet. Eating carbs increases serotonin, which you might find in short supply if you’re not getting enough natural light. Be aware that while this may give you an initial pick-me-up, the drop afterwards just isn’t worth it. Plus these foods deplete vital vitamins and minerals that help the body handle stress and build immunity.
  • Invest in full spectrum light bulbs and consider purchasing a light box, especially if you live in a Northern latitude.
  • Practice stress reduction or energy medicine. Women who practice meditation or other methods of deep relaxation are able to alleviate many of their PMS and seasonal blues symptoms. Relaxation of all kinds decreases the stress hormones cortisol and epinephrine levels in the blood and helps to balance your biochemistry.
  • Get at least twenty minutes of aerobic-type activity three times a week. Brisk walking during sunlight hours—especially without sunglasses so your eyes absorb the light—can boost endorphins. It’s estimated that half of all depression cases can be helped through exercise alone. (Read Women’s Bodies, Women’s Wisdom, Chapter 18 for more information.)

It’s not uncommon to feel a shift in energy and mood as the seasons change. However, if these symptoms are excessive, they shouldn’t be ignored. So seek the help of a professional if they are severe. In the meantime, adopt as many of my suggestions as you feel comfortable with. Not only will they chase away the winter blues, they’ll help you stay healthy at the cellular level, too.

Learn More — Additional Resources


  1. Parry, B.L., et al., 1991. Morning vs. evening bright light treatment to late luteal phase dysphoric disorder, Am J Psych, 146:9. 
  2. Ott., J., 1978. Health and Light, New York: Pocket Books.
  3. Kime, Z., 1980. Sunlight Could Save Your Life, Penryn, CA: World Health Publications.
  4. Lieberman, J., 1991. Light: Medicine of the Future, Santa Fe: Bear & Company.
  5. Rao, M.D., Muller-Oerlinghausen, B., Volz, H.P., 1990. The influence of phototherapy on serotonin and metatonin in non-seasonal depression, Pharmocopsych, 23:155-58.
Last Updated: September 17, 2009

Christiane Northrup, M.D.

Christiane Northrup, M.D.

Christiane Northrup, M.D., is a visionary pioneer and a leading authority in the field of women’s health and wellness. Recognizing the unity of body, mind, and spirit, she empowers women to trust their inner wisdom, their connection with Source, and their ability to truly flourish.

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