How Much Sun Does a Person Need to be Healthy

How Important Is Sunlight In Being Healthy?

Edited and Published by Wellness Monster Louise

How Sunlight Affects Skin

The skin is the largest organ of the body containing several layers made up primarily of collagen, a protein-rich connective tissue that helps to keep skin plump and healthy. The skin is also made up of two other protein-based compounds, elastin and keratin. Elastin keeps skin elastic, and diminishes with age and keratin, found in highest concentration in the hair and nails, helps to protect the skin and last, but not least, the mineral silica helps the body to produce more collagen, elastin, and keratin. Keratin compounds assist the body in correcting skin diseases, such as psoriasis, vitiligo, scleroderma, lupus vulgaris and actinic keratosis (Body Into Balance, 2016). A healthy supply of keratin is largely dependent on skin being exposed to the sun, as adequate sun exposure plays a role in encouraging new skin cell growth and an even larger role in helping the body to reproduce keratin by activating certain chemical reactions in the body to produce Vitamin D.

Very basically, when skin is exposed to sunlight, it makes vitamin D from cholesterol. The ultraviolet B (UVB) rays from the sun combined with the compound 7-dehydrocholesterol in the skin cells provide the energy for vitamin D synthesis to occur. The natural form of Vitamin D made by the body from ultraviolet rays of sunlight is Vitamin D3, which is the end result of a conversion process orchestrated by the kidneys and the liver. Vitamin D controls blood calcium and is actually a hormone known as calcitriol. Calcitriol is the active form of the vitamin in the body. There are two forms of Vitamin D; Vitamin D2 and Vitamin D3. Both, Vitamin D2 and Vitamin D3 can be used by the body. However, research suggests that Vitamin D2 (ergocalciferol) is less effective than Vitamin D3 (cholecalciferol). Vitamin D2 comes from plant-sourced foods while Vitamin D3 is only found in animal and fish sources of food.

Benefits of Vitamin D

3d model of Vitamin D3As already stated, Vitamin D supports dietary calcium absorption in the gut and along with weight-bearing exercises, improves the body’s ability to build and maintain strong, healthy bones. It blocks the release of parathyroid hormone (a hormone that degrades bones, making them brittle). Vitamin D also helps to prevent rickets in children (soft bones), osteomalacia (deformed bones in adults), frequent sickness and infection by supporting the immune system, prevents muscle and bone aches and pain, fatigue, irritability, and depression.

A Little About Vitamin D Deficiency and How to Avoid It

Factors that lead to Vitamin D deficiency include: older age, lower activity levels, darker skin color, Crohn’s disease, Celiac disease, osteoporosis, kidney and liver diseases, gastric bypass surgery, obesity, menopause (Vitamin D deficiency also precipitates low estrogen in women), andropause, and certain medications (prednisone, cholestyramine, colestipol, phenobarbital and phenytoin, rifampin and orlistat). Breast milk contains less Vitamin D than store-bought milk and infant formulas, which contributes toward infants being at risk for Vitamin D deficiency.

It’s important to note that sunscreens and standing behind glass windows prevent Vitamin D from being produced in the body as ultraviolet light is unable to penetrate these barriers. In order to maintain healthy levels of Vitamin D from direct sunlight the skin on the face back, arms or legs should be exposed to early morning or late evening sun to the back, face, arms or legs for 5-15 minutes (up to 40 minutes for darker skin) during spring and summer months. How much vitamin D the body actually creates from exposure of the sun depends on several factors, such as the time of year, the time of day, cloud cover, and quality of air (i.e., pollution, smoke, etc.).

During colder months or when living in northern climates, it may be impossible to absorb enough sunlight to maintain a healthy level of Vitamin D. It may be necessary to use Vitamin D supplements during this time. 400-1200 units of Vitamin D3 each day can be helpful although this may still not be enough. Keep in mind, the safety drop off for Vitamin D is 2000 units per day unless otherwise medically advised. Vitamin D is stored in fat in the body to be used as needed, which is why taking more than you need in supplement form can cause toxicity. Symptoms of Vitamin C toxicity include poor appetite, nausea and vomiting, stomach pain, constipation or diarrhea, elevated blood calcium levels, bone loss, and kidney failure. It should also be noted that Vitamin D should also never be combined with Vitamin A. meaning, these two supplements should not be taken together at the same time, as they compete with each other.

Foods With Vitamin D

shellfish provide vitamin d

Foods containing Vitamin D2:

  • Vitamin D fortified foods, such as dairy products, butter, corn flakes, raisin bran, and granola.
  • Leafy green vegetables
  • Orange juice
  • Mushrooms that are grown with exposure to the sun or UV rays or placed upside down under the sun for 4-6 hours.

Foods containing Vitamin D3:

  • Seafood: Atlantic mackerel, tuna (canned in water), cod, sardines, swordfish, salmon (salt water), herring, mackerel, and shellfish.
  • Liver
  • Pasteurized eggs (egg yolk)

While it seems generally agreed upon that Vitamin D fortified dairy products and dietary supplements, such as fish oils and cod liver oil, do appear to work in the body to make calcitriol, they do not appear to work as well as whole foods to produce Vitamin D. There also seems to be some controversy over whether sunlight provides Vitamin D better than whole foods in maintaining healthy Vitamin D levels. However, according to endocrinologist Karl Insogna, MD, director of the Yale Medicine’s Bone Center, “The body can use each just fine.” Still, other sources lean toward sunlight being the best choice for optimal Vitamin D levels, due to a process that takes places in the skin before UV rays are ever converted into Vitamin D.


In summary, it appears getting a daily dose of sunlight during the spring and summer months, applying sunscreens only after the initial 5-15 minutes of sun exposure, eating whole foods containing Vitamin D, and using supplements to deter deficiencies, is best for maintaining healthy levels of Vitamin D in the body. And it is always suggested to speak with a physician about any suspected deficiencies.


Body Into Balance: An Herbal Guide to Holistic Self-Care by Maria Noel Groves, 2018. [] [] [] []

ValeMedicine []

Photo Credits:

Woman Enjoying Sunlight [ID 116358508 © Soleg1974 |]

3d Model of Vitamin D3 [By Ben Mills – Own work, Public Domain,]

Woman Enjoying Shellfish [ID 77455197 © Piotr Marcinski |]