FWBW 5: Brightening Up Your Thyroid’s SAD Day


In my mid-twenties, or perhaps even before then, I began to feel the urge to hibernate every winter. It seemed that I was never a morning person during the rest of the year, but in winter it got particularly bad. I was very sensitive to the change in seasons and I attributed my extra tiredness in winter to SAD or Seasonal Affective Disorder. Last year, I found out that I had Hashimoto’s (autoimmune underactive thyroid) which certainly explains the years of relentless exhaustion. What I found particularly interesting when I was first reading up on the symptoms is that hypothyroid patients are actually more prone to SAD. So what is this miserable disorder and how should we deal with it?

(S)easonal (A)ffective (D)isorder describes a phenomenon where certain susceptible individuals suffer from a complex of symptoms as the winter heralds its arrival. It typically begins in September and eases up around the end of March or the beginning of April. Symptoms include increased tiredness, insomnia and oversleeping, depression or worsening of an existing depression and carbohydrate cravings. As our body temperatures drop, our energy requirements rise by as much as 40 percent, which is why many people eat more in winter and tend to put on weight. Because it is darker in winter, our levels of the sleep-inducing hormone melatonin rise and studies show that this induces carbohydrate cravings as an instant fix to the resulting drop in body temperature and our loss of energy.

One reason hypothyroid sufferers are more prone to SAD is because the thyroid has to work extra hard when the temperatures drop and there is a reduced level of circulating thyroid hormones. As a result, it makes sense to ask your doctor to check your thyroid hormone levels at the onset of the chilly season to ensure that your thyroid is producing sufficient hormones. Some doctors even routinely prescribe extra thyroid hormone to counteract this effect. One study suggested that extreme cold (in this case in Antarctica) caused the muscles to store thyroid hormone in an effort to maintain body temperature. This meant the brain was not getting enough and so it was postulated that such SAD sufferers (including those in warmer climates) be given supplementary thyroid hormone to boost their thinking and concentration and to ease depression.

To make matters worse, those with hypothyroidism are more sensitive to the cold anyway because we tend to have a lower body temperature. There are several ways to tackle this and thyroid patients have suggested their own personal strategies here: How do you Survive and Thrive During the Winter.

People with certain thyroid disease-related conditions seem to be more prone to SAD. Such conditions include Chronic Fatigue Syndrome, fibromyalgia, candida, irritable bowel and leaky gut. Imbalances in the gut (gut dysbiosis) can trigger SAD by interfering with serotonin function. Serotonin (the “happy hormone”) is produced from the amino acid tryptophan which we get from protein foods. However, when an imbalance is present, unfriendly microorganisms such as bacteria and yeast selfishly “grab” the tryptophan for themselves before we have chance to absorb it through our intestines, causing serotonin deficiency and resulting in various forms of depression such as SAD.

You may be curious as to the exact causes of SAD. Allow me to explain here that SAD sufferers have disrupted circadian rhythms – in other words, their body clock needs a trip to the watch maker. Sunlight synchronises this body clock but the bodies of SAD sufferers may produce hormones such as cortisol and neurotransmitters that keep them awake into the wee small hours of the morning, whilst their body produces sleep-inducing chemicals such as melatonin until midday, causing them to struggle to get up in the mornings.

The reason for this is clear. When the light fades in the evening, the pineal gland begins producing melatonin, a messenger hormone that travels through the blood, lowers our body temperature and tells our body to go to sleep. In those who don’t suffer from SAD, melatonin production peaks in the middle of the night during deep sleep. At dawn, sunlight shines in our eyes and the suprachiasmatic nucleus (SCN), a small cluster of brain cells, tells the pineal gland to increase its temperature, deactivate melatonin production and wake up (pretty much like the body’s own solar power system). An interesting study suggested that lighter eye colours such as blues and greens are less susceptive to SAD because they let in more light. Melatonin can have a major effect on other hormones. Normally, hormone production from the thyroid and adrenals (cortisol and adrenaline) winds down during the peak of our melatonin production, in the middle of the night. However, for SAD sufferers this process is reversed during the winter months and melatonin levels are higher during the day, which leads to sleepiness and a reduction in these hormones that are so vital for our energy levels and metabolism. Research suggests that taking melatonin supplements between 9 and 10 in the evening may restore normal circadian rhythms and enable SAD sufferers to sleep better at night and be more awake during the day. These are available over the counter in the US. However, I should mention that some people with active autoimmune disease might experience flares in their symptoms or even wake up groggy. As with any supplement, use with caution and as everyone is an individual, everyone will have different experiences. My antibodies are not active and melatonin has worked fine for me without any problems whatsoever.

I mentioned the “happy hormone” serotonin above. Healthy serotonin levels and functioning serotonin stimulation of the brain cell receptors are vital to maintain a good mood and ward off depression. Studies show that serotonin levels are at their lowest in winter and that SAD patients suffer from a serotonin deficiency during the day and a malfunctioning of the serotonin transmission in the brain. Serotonin is converted into melatonin and during the day healthy individuals experience low melatonin production and high serotonin production, thus giving us our get-up-and-go. However, it’s the opposite for SAD sufferers who experience high melatonin and low serotonin during the day, which leads to negative emotions and a lack of energy. Because of the serotonin connection, some people recommend taking 900 mg of St John’s wort one month prior to the onset of SAD symptoms. However, it is important to note that this herb (which is actually the most popular antidepressant prescribed in Germany for mild to moderate depression) is renowned for its side effects and interactions with other drugs, so it is best to check online or with your doctor or pharmacist.

Vitamin D also plays a vital role in a healthy body clock. SAD is caused by insufficient exposure to UV rays which are produced when sunlight hits our skin. SAD sufferers often suffer from Vitamin D deficiency and may benefit from Vitamin D supplements. In my experience, this seems to be a very common deficiency in thyroid patients anyway. Some people treat this by going to a tanning salon, which is known to induce good moods in SAD patients.

Other doctors such as the renowned Chronic Fatigue Syndrome specialist Dr. Teitelbaum are proponents of bright light therapy. Dr. Teitelbaum recommends using a 10,000 lux lightbox for 30 to 45 minutes every morning in winter (although some doctors recommend use of up to three hours daily). 10,000 lux is five- to twenty-times the intensity of normal lighting in your home or office. This simulates the frequency of sunlight and can thus alleviate SAD symptoms. Take care not to stare directly into the light due to potential eye damage, but make sure that it is close enough to supply you with the ideal dosage. Some SAD patients find it helpful to set their lamp’s automatic timer two hours before waking to create a natural sunrise effect. If you are wondering where to find such lights, the following two sites might be a good starting point: Lumie and Sunbox.

Of course, there are also other tips to prevent or reduce SAD. Eat a low-fat, healthy diet with sufficient proteins and eliminate sugar and carbs wherever possible. Sadly, we members of the “Jacked Thyroid Club” are frequently more sensitive to processed sugar, candida overgrowth, abnormal blood sugar levels and food allergies. Eliminating caffeine is also said to help, although I suspect that many SAD sufferers actually use caffeine to boost their energy levels during winter, so this may be a tough one. Certain vitamins and supplements such as magnesium, B complex, ferritin and those mentioned above (Vitamin D, melatonin and St. John’s wort) may prove effective. Upping your daily exercise and wherever possible taking walks outside is known to be beneficial. Doctors recommend 20 to 30 minutes of outdoor light exposure a day. If you don’t have the energy to go for a walk, run errands in your car with the window down. Don’t forget that sunglasses decrease the benefit of sunlight. If you suffer from SAD, leave your lights on at home and don’t spike the electricity bill by constantly turning them on and off. And last but not least, make sure you get enough sleep. With a healthy thyroid, you need around seven to eight hours, but when your thyroid is being rebellious, you may well need even more, particularly in winter.

To read more on a related topic, check out my article on spring tiredness, which also talks a little about reverse (summer) SAD.


  1. Search for SAD/Seasonal Affective Disorder
  2. Don’t Let Low Thyroid Make You SAD
  3. Weary Winter and My Experience with My Thyroid and SAD
  4. Seasonal Affective Disorder
  5. SAD: About Light, Depression and Melatonin
  6. SAD Real and Treatable
  7. Sleeping Too Much? You could be SAD

By Sarah Downing

My name is Sarah. I was born and grew up in England and currently live in Düsseldorf, Germany, with my fiancé Corey and my cuddly cat Biscuit. I work as a translator and writer for my own company Aardwolf Text Services (www.aardwolf.de) and I love vintage clothes and music, as well as singing karaoke.


  1. Thank you so much for this article. i am new to being hypothyroid, so this is my 2nd winter experiencing the above. thank you so much for shedding on light what dr.’s wont tell you about why i was wondering why i felt hungrier w/ carbs & thought it had something to do w/ temperature. i have tried to keep up my walking as it boosts my metabolism, makes me mentally feel better, warms me up, helps my lack of energy and helps with the bloating. glad to know “i’m not crazy” for feeling hungrier. thanks!

    1. Glad you liked the article, Mel and that it was able to help you. I was quite fascinated to learn more about SAD as I do tend to have a little less energy in winter. It used to be a lot less, but since I’ve been on the thyroid meds and my doc generally adjusts them in wintertime I’ve been feeling so much better, but it has to be the NDT (Natural Desiccated Thyroid) for me to feel really good. Shortly after my diagnosis, I also began taking a really good multivitamin and I suspect that that has also helped. I don’t think my D levels are quite where they need to be yet, but they are certainly a lot better than when I started. I haven’t tried the light therapy yet, but now that my thyroid is more balanced winter isn’t nearly as debilitating. Last winter was hell and I could hardly get out of bed or off the couch – probably didn’t help that I also had Epstein-Barr virus at the time. Good for you for doing your walking. I have to go to the doctor now to get myself pricked all over again! I was thinking of taking a taxi as I really can’t be arsed this morning, but maybe I should walk after all …



  2. My SAD has something to do with my thyroid med, which is made from pig hormone. The only time in my life that I experienced SAD was a couple of times when going through puberty in northern North Dakota in the winter. I didn’t experience it again until I switched from synthetic thyroid medication to Armour, which is made from the thyroid of pigs. Armour works well for most thyroid patients and was the gold standard of treatment before the synthetics were invented. Human hormones and pig hormones are almost identical and that is why Armour works so well for us. However.. I never experienced SAD when I was on the synthetics. Only when I switched to Armour. I know that the hormones in Armour are tied in with my SAD. I just want to know how to deal with it!

    1. That’s interesting, Marilyn. I’ve never heard that before, but everybody reacts differently. Do you feel better on Armour overall, or do you do better on Synthroid? Some people actually do do better on the synthetics. I think we should have access to whatever works best for us.



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