In Parts 1 and 2, I wrote about the impact of light therapy and diet on managing the symptoms of seasonal affective disorder (SAD) and its milder form, the ‘winter blues’. In Part 3 we’ll look at further nutritional support for this common disorder.
As there are fewer daylight hours in the winter months, levels of Vitamin D in the body can drop. While light boxes represent a promising treatment option for SAD, they do not provide UV light and so will not boost Vitamin D levels. Researchers have tested whether Vitamin D supplementation can improve mood during the winter months. A double-blind study found that mood improved in healthy people without SAD who received 400 or 800 IU per day of vitamin D for five days in late winter (1).
Another study tested the effects of supplementation with either 600 or 4000 IU of vitamin D every day for six months (2). Both dosages led to improved mood and general well-being in the participants, with those on the higher dose experiencing greater benefits.
Although additional research needs to be done before any conclusions can be made, the available evidence suggests that people with SAD who have low levels of vitamin D might benefit from supplementation.
The Western diet, high in animal produce and refined carbohydrates, leaves us vulnerable to deficiency in the mineral magnesium. This may affect mood, because conversion of tryptophan to mood-enhancing serotonin is dependent on sufficient levels of magnesium. Studies indicate that an insufficient level of magnesium can alter also levels of melatonin and upset the body’s biological clock, a pattern that is seen in SAD (3).
Supplementing with magnesium can be recommended to those with insufficient intake. I prefer the forms magnesium citrate or magnesium taurate, which are bioavailable, well-absorbed forms.
I wrote about the importance of omega 3 in optimising serotonin levels in Part 2. These oils appear to have a natural anti-depressant action, and their effect on mental health has been widely studied. While omega-3 can be supplied through oily fish in the diet, those who are concerned with levels of mercury in fish might want to try supplementing with a fish oil that has been screened for contaminants.
St John’s Wort
St John’s Wort is widely recognised as an effective supplement for mood disorders, and one small randomised study has investigated its benefit for those with SAD (4). The blinded study tested the effects of a daily dose of 900mg of St John’s Wort over 4 weeks. It concluded that the supplement may be an efficient therapy for those with SAD, though further research is needed.
This herb is thought to increase serotonin levels by inhibiting serotonin reuptake, working in a similar way to conventional selective serotonin reuptake inhibitor (SSRI) antidepressants. If you are using a light box to relieve SAD or the ‘winter blues’, then you should check with your GP before taking St John’s Wort, as this herb can make your eyes more sensitive to light.
As winter approaches, the short days and long nights of the season can make life difficult for those with SAD. Even in its milder form, the ‘winter blues’, symptoms of low mood, fatigue and weight gain can make life miserable. The good news is that some fairly simply lifestyle adjustments can make a positive difference. Using a sunrise alarm clock in the mornings for instance can also help you get out of bed on the “right side”. The evidence for bright light therapy with an approved light box is compelling, and coupling this with nutritional support might just help you to banish those winter blues for good.
Written by Nadia Mason
1. Lansdowne AT, Provost SC. Vitamin D3 enhances mood in healthy subjects during winter. Psychopharmacology (Berl) 1998.135:319–23.
2. Vieth R, et al. Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU) per day on biochemical responses and the wellbeing of patients. Nutrition Journal 2004. 3:8
3. Wester PO. Magnesium. Am. J. Clin. Nutr. 1987. 45 (5 Suppl): 1305–12. PMID 3578120
4. Durlach J, Pagès N, Bac P; Bara M, Guiet-Bara A, Agrapart C
Chronopathological forms of magnesium depletion with hypofunction or with hyperfunction of the biological clock. Magnesium research : official organ of the International Society for the Development of Research on Magnesium 2002.15(3-4):263-8.
5. Kasper S. Treatment of seasonal affective disorder (SAD) with Hypericum extract. Pharmacopsychiatry 1997. 30:89-93.