Avoiding the sun may be as bad as smoking - many studies

---

What If Avoiding the Sun Is Bad for You? July 2019

• “If that study’s findings are correct,” Zirwas says, “that means protecting yourself from ultraviolet light could have the same effect on your mortality as deciding to smoke a pack of cigarettes a day.”

The study: Avoidance of sun exposure is a risk factor for all‐cause mortality: results from the Melanoma in Southern Sweden cohort - 2014

 Download the PDF from VitaminDWiki
154 studies referemce the 2014 study as of May 2025

---

VitaminDWiki - Smoking reduces vitamin D - many studies

---

Example pages in VitaminDWiki

• Avoiding the Sun is Just as Dangerous as Cigarettes - video March 2024
• Which Is Worse - Avoiding Sunlight or Vitamin D Deficiency – April 2019
• Have We Gotten Sunscreen Totally Wrong - Jan 2019
• Embrace the Sun – benefits of the sun (Nitric Oxide etc.) – book June 2018
• Low Vitamin D is worse for your health than smoking
• The Greatest Public Health Mistake of the 20th Century (sunscreen block Vitamin D) - 2017
• Low UVB (thus low Vitamin D) is linked to many diseases – Grant Jan 2016
• Avoiding the sun reduces lifespan by 2 years (smoking reduces lifespan by 10 years) – March 2016
• Sunbathing (vitamin D) increases lifespan in Sweden by about 1 year – March 2016
• The risks and benefits of sun exposure – Holick Oct 2016
• Low UVB (thus low Vitamin D) is linked to many diseases – Grant Jan 2016
• Many wavelengths of light provide health benefits, not just UV – March 2016
• Less sun means more disease -Grant, Holick, Cannell, et al Feb 2015
• Sun avoidance increases risk of death by 2X – April 2014
• UV, sunshine, and vitamin D (87 charts) - Holick March 2013
• Why do gardeners live longer (vitamin D, etc.)
• Overview Suntan, melanoma and vitamin D
• Less Solar Radiation was associated with more Cancer - 1941
• Sunny side of the hill is the healthiest – 400BC
• 2200X more problems from no UVB than too much UVB - WHO 2006 - chart by VitaminDWiki
  

---

Is Avoiding the Sun as Detrimental to Health as Smoking? - Perplexity AI Deep Research Report May 2025

A growing body of research suggests that completely avoiding sunlight may have serious negative health consequences comparable to those of smoking. This comparison, while initially surprising, is supported by longitudinal studies showing similar reductions in life expectancy between sun avoiders and smokers. This report examines the scientific evidence behind this claim, explores the health benefits of sunlight, and considers the optimal balance between sun exposure and protection.

The Swedish Sunlight Studies: Key Evidence for the Comparison

The primary evidence for comparing sun avoidance to smoking comes from a landmark Swedish study that followed nearly 30,000 women over 20 years. Researchers from the Karolinska University Hospital found that nonsmokers who avoided sun exposure had a life expectancy similar to smokers who had the highest sun exposure levels 7 14 16. This led researchers to conclude that "avoidance of sun exposure is a risk factor for death of a similar magnitude as smoking" 7 10.
The study revealed that compared to those with the highest sun exposure, life expectancy for those who avoided the sun dropped by 0.6 to 2.1 years 14 18. For context, research indicates that completely eliminating tobacco use would increase life expectancy by 1.2 years for women and 1.6 years for men 12, suggesting comparable mortality impacts between sun avoidance and smoking.

Dose-Dependent Benefits of Sunlight

A key strength of the Swedish research was demonstrating dose-specific results-the benefits of sunshine increased with higher exposure levels 7 16. Women who actively sought sunlight showed lower risks of cardiovascular disease and non-cancer/non-CVD conditions including diabetes, multiple sclerosis, and pulmonary diseases compared to those avoiding sun exposure 14 16 18. This pattern remained consistent even when accounting for other health factors.
Interestingly, while women with greater sun exposure had longer lifespans, the relative proportion of cancer deaths was higher in this group 14. This seemingly paradoxical finding occurs because these women lived longer overall, reaching ages where cancer risk naturally increases.

Health Benefits of Sunlight Exposure

Vitamin D Production and Beyond

The most well-known benefit of sunlight is stimulating vitamin D synthesis. When UVB rays interact with proteins in human skin, they produce vitamin D3, which supports bone health, calcium regulation, reduced inflammation, and immune system function 1 15 19. However, emerging research indicates sunlight's health benefits extend beyond vitamin D production.

Cardiovascular and Metabolic Benefits

Research has identified links between sun exposure and lower blood pressure, with potential reduced mortality from cardiovascular issues 19. One mechanism involves sunlight triggering the skin to release nitrogen oxides, which dilate arteries and lower blood pressure 19. Regular sunlight exposure appears to reduce the impact of metabolic syndrome and may decrease the risk of type 1 diabetes 2 3 19.

Neurological and Mental Health Benefits

Sunlight exposure stimulates serotonin production-often called the "happy hormone"-which improves mood and may reduce symptoms of depression 9 17. Regular exposure to natural sunlight helps regulate our circadian rhythms, contributing to better sleep quality 13 17. Additionally, sunlight triggers the release of endorphins, our natural stress relievers, promoting relaxation and increased energy levels 9 17.

Potential Protection Against Chronic Diseases

Some evidence suggests adequate sun exposure may protect against multiple sclerosis, Alzheimer's disease, and certain cancers including breast, colon, and prostate cancer 2 3 19. One study concluded that long-term high sun exposure throughout life could reduce the risk of cognitive impairment in later years 2.

The Public Health Impact of Insufficient Sun Exposure

The scale of potential harm from insufficient sunlight is substantial. Research indicates that "sunshine deficiency" could be responsible for approximately 340,000 deaths annually in the United States and 480,000 deaths yearly in Europe 2 3. These figures are comparable to the mortality impact of major public health challenges, including smoking.
Researchers have identified numerous diseases associated with insufficient sun exposure, including cancer (especially breast and colon cancer), hypertension, cardiovascular disease, metabolic syndrome, multiple sclerosis, Alzheimer's disease, autism, asthma, type 1 diabetes, and myopia 2 3. This broad spectrum of conditions underscores sunlight's fundamental role in human health.

Critical Perspectives and Limitations

Questioning the Comparison

Some medical professionals question the direct comparison between sun avoidance and smoking. Dr. Adam Friedman suggests that individuals with increased sun exposure may simply be more active, healthier, and more socially engaged than those who avoid the outdoors 6. He also notes that vitamin D can be obtained through diet and supplements rather than sun exposure alone.

Acknowledged Limitations in the Research

The Swedish researchers acknowledged limitations in their study, including the inability to fully differentiate between active sun-exposure habits and an overall healthy lifestyle 18. They also lacked comprehensive exercise data, which could be a confounding factor in longevity differences.

Skin Cancer Considerations

The researchers found an increased risk of skin cancer among those with greater sun exposure but noted that "the skin cancers that occurred in those exposing themselves to the sun had better prognosis" 7 16. This suggests that while skin cancer risk increases with sun exposure, the types of skin cancers that develop may be less aggressive or more treatable.

Finding the Balance: Sensible Sun Exposure

From Avoidance to Smart Protection

Medical consensus increasingly favors balanced sun exposure over complete avoidance. As Dr. Lindqvist stated: "We know in our population, there are three big lifestyle factors [that endanger health]: smoking, being overweight, and inactivity. Now we know there is a fourth-avoiding sun exposure" 7 16.

Guidelines for Safe Sun Exposure

Experts recommend "moderate UV exposure from the sun, without burning" 2. Specifically, sun exposure should be obtained incrementally at not more than 5–30 minutes per day, depending on skin type and UV index 3. This approach allows for vitamin D synthesis and other health benefits while minimizing skin damage risks.

Population-Specific Considerations

The impact of sun avoidance may be particularly problematic in regions with low solar intensity. Sweden's restrictive guidance against sun exposure over four decades may be especially ill-advised in a country where the maximum UV index is low for up to nine months of the year 7 16. Similarly, individuals with darker skin pigmentation may need more sun exposure to achieve the same health benefits as those with lighter skin 18.

Conclusion

Current evidence suggests that completely avoiding sun exposure may indeed carry mortality risks comparable to smoking. While this comparison initially seems counterintuitive given longstanding public health messaging about sun protection, a growing body of research supports the vital role of moderate sunlight in human health.
The key appears to be balance-neither complete avoidance nor unrestricted exposure. As one researcher summarized: "We do not advocate sun avoidance, but sun safety" 6. This approach acknowledges both the established risks of excessive UV radiation and the emerging understanding of sunlight's essential role in human physiology.
For optimal health, individuals should seek regular, moderate sun exposure appropriate for their skin type and location while using proper protection to prevent sunburn and excessive UV damage. This balanced approach may help reduce mortality risks while still protecting against skin cancer-allowing humans to benefit from our evolutionary relationship with the sun.

Citations:

1. https://pmc.ncbi.nlm.nih.gov/articles/PMC2290997/
2. https://www.grassrootshealth.net/blog/diseases-associated-sunshine-deficiency/
3. https://pmc.ncbi.nlm.nih.gov/articles/PMC7400257/
4. https://ec.europa.eu/health/scientific_committees/scheer/docs/sunbeds_co4a_en.pdf
5. https://www.naturalmedicinejournal.com/journal/avoiding-sun-exposure-lethal
6. https://www.namd.org/journal-of-medicine/1733-avoiding-the-sun-is-as-bad-as-smoking.html
7. https://www.medscape.com/viewarticle/860805
8. https://www.cdc.gov/tobacco/about/benefits-of-quitting.html
9. https://www.webmd.com/a-to-z-guides/ss/slideshow-sunlight-health-effects
10. https://www.humannaturenaturalhealth.com/patient-resources/Articles/SunAvoidanceSmoking
11. https://pedagogyeducation.com/News/Why-Sunlight-Deficiency-is-as-Deadly-as-Smoking
12. https://www.cdc.gov/pcd/issues/2012/11_0295.htm
13. https://health.clevelandclinic.org/how-much-sunshine-you-need-daily
14. https://pubmed.ncbi.nlm.nih.gov/26992108/
15. https://www.goodrx.com/health-topic/environmental/benefits-of-sunlight
16. https://oregenmed.com/sun-exposure-benefits/
17. https://news.cuanschutz.edu/health-and-wellness/hello-sunshine
18. https://www.linkedin.com/pulse/avoiding-sun-dangerous-smoking-dr-patrick-j-treacy
19. https://www.medicalnewstoday.com/articles/benefits-of-sunlight
20. https://www.grassrootshealth.net/blog/public-health-recommendations-contradict-benefits-sunshine/
21. https://ar.iiarjournals.org/content/38/2/1173
22. https://vitamindwiki.com/Avoiding+the+sun+reduces+lifespan+by+2+years+(smoking+reduces+lifespan+by+10+years)+%E2%80%93+March+2016
23. https://www.cdc.gov/Mmwr/preview/mmwrhtml/00001800.htm
24. https://pmc.ncbi.nlm.nih.gov/articles/PMC11234345/
25. https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5745a3.htm
26. https://www.cnn.com/2025/01/01/health/cigarette-smoking-life-expectancy-study-wellness
27. https://pmc.ncbi.nlm.nih.gov/articles/PMC2598467/
28. https://www.tobaccoinduceddiseases.org/pdf-147656-76126?filename=Assessment+of+association.pdf
29. https://pmc.ncbi.nlm.nih.gov/articles/PMC4771605/
30. https://pubmed.ncbi.nlm.nih.gov/10218754/

---

There have been 13367 visits to this page