Daily Sun Exposure

Daily Sun Exposure

03 Dec

Daily Sun Exposure

The sun. What would we do without it? Die faster.

The end.

Just kidding.

One of the simplest ways we can increase performance, recovery, mood, digestive health, immune function, and neurological health is by getting direct sunlight each day. Let’s break down these benefits and see how we can start implementing direct skin exposure to maximize the sun’s powerful effect on our body.

Vitamin D

Most important benefit of direct sunlight? Vitamin D. Vitamin D is a fat-soluble secosteroid that increases intestinal absorption of Magnesium (which is responsible for over 300 enzymatic processes in the body alone), Calcium, Phosphate in addition to playing a vital role in multiple biological processes. According to data from the Endocrine Society, nearly everyone in the United States, Europe, and Canada are Vitamin D deficient. Additionally, food sources are not a robust source of vitamin D. The most powerful source of vitamin D is found in UV light exposure from the sun. Our skin uses UV light to synthesize Cholecalciferol (Vitamin D3) which is sent to the liver to be converted into its active form.

Mood Booster

Serotonin is a neurotransmitter that plays a part in regulating our emotional state. We know from research that vitamin D is needed to convert tryptophan to serotonin. By ensuring our vitamin D levels are in optimal ranges we can optimize our ability to create enough serotonin allowing us to regulate our mood more effectively.

Balances Circadian Rhythm

As mentioned in one of my previous posts discussing circadian rhythm, our body operates on a clock driven by the Suprachiasmatic Nucleus (SCN). The SCN is regulated by the sun and moon. Sunlight stimulates activity and wakefulness while darkness stimulates rest and recovery. By getting direct sunlight on the skin each day when the sun is at the highest in the sky we will keep our SCN in rhythm and subsequently lower overall stress on the nervous system.

Supports Immune Function

Gut health is directly tied to immune function and health. Vitamin D has been shown to decrease gut permeability due to strengthening of the microvilli. Decreased gut permeability will prevent malabsorption of nutrients. Additional research looking at Vitamin D’s effect on immune-related disorders have shown promise in modulating the effects of:

  • Type 1 Diabetes
  • Rheumatoid arthritis
  • Autoimmune thyroid disease
  • Multiple sclerosis
  • IBD
  • Certain cancers: Colorectal, Breast, Prostate, and Non-Hodgkin’s lymphoma

In addition, “Sun exposure has been shown to protect against digestive tract disease and inflammation, specifically diverticulitis and inflammatory bowel disease. It has been shown that children getting sun exposure have decreased occurrence of eczema and runny nose.”

Increased Strength and Lean Mass

Research has shown a strong connection with optimal vitamin D levels and strength, lean mass gains. Vitamin D plays a vital role in hormonal development and immune function. In order to maximize our ability to synthesize new tissue via anabolism, which is predicated on regulating systemic inflammation and stress, optimal vitamin D levels will aid in this process.

Keys for sun exposure to maximize vitamin D absorption:

  • Direct sunlight on as much of the skin as possible each day
  • 15-30 minutes per day
  • Between 11am – 3pm when the sun’s rays are the strongest
  • People with dark(er) skin will require 3 to 5 times longer exposure to the sun to receive the absorption needed
  • Wearing sunscreen with SPF 30 will reduce vitamin D synthesis by more than 95% (*Remember, we need direct skin contact each day to utilize the benefits of the sun)
  • We never want to “burn”

Get enough sunlight on exposed skin within the time limits listed above, then add protection as needed (*Be weary of sunscreen and the chemicals within products; we are putting chemicals directly onto our skin which will then be absorbed. Look for higher quality products back by reputable dermatologists)



Rhee, Han & Vries, Esther & Coebergh, Jan. (2016). Regular sun exposure benefits health. Medical Hypotheses. 97. 10.1016/j.mehy.2016.10.011.

Lee, David & Tajar, Abdelouahid & Pye, Stephen & Boonen, Steven & Vanderschueren, Dirk & Bouillon, Roger & W O'Neill, Terence & Bártfai, György & F Casanueva, Felipe & D Finn, Joseph & Forti, Gianni & Giwercman, Aleksander & S Han, Thang & Huhtaniemi, Ilpo & Kula, Krzysztof & E J Lean, Michael & Pendleton, Neil & Punab, Margus & Wu, Frederick. (2011). Association of hypogonadism with vitamin D status: The European Male Ageing Study. European journal of endocrinology / European Federation of Endocrine Societies. 166. 77-85. 10.1530/EJE-11-0743.






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