The wintery grey skies are upon us for a good portion of the country and that means some people will experience or suffer from seasonal depression. Seasonal depression or, the fancy clinical term, “Seasonal Affective Disorder (SAD)”, is real and can really be the “Grinch” that steals the joy during the holidays for some.

A large percentage of the population suffers from SAD across the country with more prevalence as the number of day light hours decreases. It also is more prevalent for the colder areas of the country because people aren’t spending as much time outdoors (Mercola, 2015).

Why is this more prevalent during the winter months? As the temperatures get colder and colder and there are fewer daylight hours, people are spending less time outside. Majority of the vitamin D metabolized by humans come from sunlight exposure which is the D3 form (can also be found in animal based foods and supplements). The other form of vitamin D, D2, is mostly man made and found in foods and dietary supplements.  If you aren’t outdoors as much (even for those individuals whom have a desk job), this means less opportunity for vitamin D metabolism; literally the first step of vitamin metabolism is exposure to sunlight on the skin. Therefore, if you aren’t receiving vitamin D through diet (there are few options for a food sourced vitamin D as it is) or sunlight exposure, imagine the vitamin D deficiency and individual can have (Institute of Medicine, 2011).

But, why is vitamin D so important? Not only can vitamin D deficiency cause clinical depression like symptoms (which we will discuss shortly), it also increases your risk of chronic disease and a whole host of illnesses. This means an increased risk of cancer by as much as 60%, type 1 diabetes, cardiovascular disease, osteoporosis, obesity, dementia, hearing loss, migraine, asthma, the common cold and the flu (Holick, 2004).

Where do you begin to determine if you are feeling the effects of low vitamin D levels? Check in with yourself. Are you feeling any of these symptoms?

  1. Irritability
  2. Tiredness or low energy
  3. Problems getting along with other people
  4. Hypersensitivity to rejection
  5. Heavy, “leaden” feeling in the arms or legs
  6. Oversleeping
  7. Appetite changes, especially a craving for foods high in carbohydrates
  8. Weight gain

(Mayo Clinic, 2016).

If you are finding yourself identifying with some of the above symptoms, there is good news! It’s easily adjustable, fixable and affordable to do so. Start by having a discussion with your primary care physician or, order a Vitamin D blood test on your own. Yes, you can order one yourself through Life Extension ( under “Blood Testing”) for $47 (then you can have one of their practitioners help you read your results or, you can take your results to your primary care physician)! The clinical level you are looking to maintain year-round is between 50-70 ng/ml to be optimal (Mercola, 2015).

If your results show below the optimal clinical levels, you may need to supplement. If you are looking for supplementation, always look for an organic vitamin D3 version that is free of additives. D3 is substantially more potent and is metabolized exponentially faster. This makes it easier to maintain optimal levels. You can also add certain fish to your diet like salmon, mackerel, tuna or, sardines to your diet as well as egg yolks (Mercola, 2012).

**Disclaimer**The information provided is by no means meant to cure, diagnose or dissuade you to seek information from your primary care physician or healthcare provider. Always check with your primary care physician or healthcare provider before changing or adding to your normal health routine. Remember, anything related to your health and body is up for discussion; ask questions, make suggestions and ALWAYS have a conversation.

Sandi Lanham, B.S.P.H

Naturopathic Physician Student

COO of Kentucky Life Realty

Partner of KASA Properties

Want to research some of the science for yourself (which I ALWAYS encourage….knowledge is power as the adage says)? Here are a few resources/references to check out:

Holick, M (2004). Vitamin D: importance in the prevention of cancer, type 1 diabetes, heart disease, and osteoporosis. The American Journal of Clinical Nutrition. Retrieved from

Institute of Medicine (US) Committee to Review Dietary Reference Intakes for Vitamin D and Calcium; Ross AC, Taylor CL, Yaktine AL, et al., editors. Dietary Reference Intakes for Calcium and Vitamin D. Washington (DC): National Academies Press (US); 2011. 3, Overview of Vitamin D. Available from:

Mayo Clinic (2016). Seasonal affective disorder (SAD). Mayo Clinic. Retrieved from

Mercola, J (2015). Simple, Inexpensive Remedies for Seasonal Affective Disorder. Mercola. Retrieved from

Mercola, J (2012). If you take oral vitamin D, you MUST avoid making this serious mistake. Mercola. Retrieved from

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