Season of birth is a good proxy for Vitamin D (for people far from the Equator)
Statistisically significant, but rarely greater than 20% change
Some health problems need Vitamin D in 2 or 3 trimesters, so are not associated with season
Perhaps some people in born in poor season will need more vitamin D all of their lives
   Note: some of the season-of-birth effects are due to low vitamin D in future season as well
Some Season of Birth studies
- Season of birth associated with many health problem (UK Biobank) – Nov 2020
- Preterm birth varies with season: 25 percent more likely if conception in autumn – Feb 2022
- Little sun in first trimester, 2.9 X more likely to have learning disabilities – June 2019
- UV at time of conception associated with Vitamin D Receptor activation 65 years later – Sept 2017
- Autoimmune Addison's Disease – increased risk if born in Dec or Jan – Nov 2016
- Schizophrenia increased 40 percent for Spring births after Danes stopped vitamin D fortification – April 2014
- Season of birth associated with Pneumonia (10 %) and Multiple Sclerosis (30 %) – May 2013
- Majority of Season of Birth health problems should vanish if take Vitamin D
 100K monthly, or 50K bi-weekly, or 4K daily
- 28 - items in "Season of Birth" Category 
- Chart of Diseases correlated to month of birth – 2008
- Chart of Schizophrenia vs month of birth
- Chart of Age of Menarche and Height vs SoB - Biobank 2015
- See related in VitaminDWiki
- Fetus development vs month of gestation (Some portions need Vitamin D during all phases)
- Season of Birth primarily associated with Pregnancy, Multiple Sclerosis. and Cognitive categories
 - 28 - items in "Season of Birth" Category - wiki page:
                        - Health Problems Associated with Low Vitamin D at Birth
- Major reduction allergies and asthma if the child was born in a sunny season (in Paris in this case) – April 2024
- Season of birth associated with many health problem (UK Biobank) – Nov 2020
- More muscle strength 80 years after being born in warm season (no surprise) – Nov 2022
- Preterm birth varies with season: 25 percent more likely if conception in autumn – Feb 2022
- Summer births associated with 2X slower gross motor development at 6 months – May 2021
- October Babies more likely to be successful, live longer, etc (Vitamin D, etc) Oct 2019
- Little sun in first trimester, 2.9 X more likely to have learning disabilities – June 2019
- Conception in winter increases rate of Autism, learning disabilities, dyslexia – Oct 2016
- UV at time of conception associated with Vitamin D Receptor activation 65 years later – Sept 2017
- Gallstones 33 percent more likely if born during winter – Dec 2016
- Autoimmune Addison's Disease – increased risk if born in Dec or Jan – Nov 2016
- Season of Birth
- Season of birth (Vitamin D) vs birth weight, puberty, body size, etc. – Oct 2015
- Health problems are related to birth month - June 2015
- Anorexia nervosa and Vitamin D - several studies
- Schizophrenia increased 40 percent for Spring births after Danes stopped vitamin D fortification – April 2014
- Hypothesis- birth rate variation with season may trump MS variation with vitamin D – Jan 2014
- Season of birth associated with Pneumonia (10 %) and Multiple Sclerosis (30 %) – May 2013
- Multiple Sclerosis 23 percent more likely if born in April vs. Oct – meta-analysis Nov 2012
- Environmental risk factors for MS include latitude and vitamin D – Sept 2012
- Association between season of birth and suicide – perhaps vitamin D – Sept 2012
- 7 percent less likely to get immune mediated disease if born in the fall – July 2012
- Odds of living to 100 increase by 40 percent if had been born in the fall – 2011
- Diseases correlated to month of birth – 2008
- Is the variation in winter babies due to vitamin D – 2009
- Hypothesis: Low vitamin D linked to Myopia
 
 
 - Chart of Diseases correlated to month of birth – 2008
 - Chart of Schizophrenia vs month of birth+- Effects of Family History and Place and Season of Birth on the Risk of Schizophrenia 
 Feb 1999 DOI: 10.1056/NEJM199902253400803
 - Chart of Age of Menarche and Height vs SoB - Biobank 2015- Season of birth is associated with birth weight, pubertal timing, adult body size and educational attainment: a UK Biobank study 
 October 2015 DOI:https://doi.org/10.1016/j.heliyon.2015.e00031
  Download the PDF from VitaminDWiki
 - See related in VitaminDWiki- Overview Deficiency of vitamin D
- Children with Kawasaki disease are 29 X more likely to be Vitamin D deficient – Jan 2022
- Cancer during childhood - many studies
- Longevity and healthspan increased by Vitamin D, Omega-3, Magnesium - many studies
- Brain and Vitamin D - many studies
 
 - Fetus development vs month of gestation (Some portions need Vitamin D during all phases)
 Details at Ensure a healthy pregnancy and baby - take Vitamin D before conception
 - Season of Birth primarily associated with Pregnancy, Multiple Sclerosis. and Cognitive categoriesSeason of Birth(Cached) Printer Friendly Follow this page for updates- 31944 visitors, last modified 10 Aug, 2025, This page is in the following categories (# of items in each category)- Attached files- ID - Name - Uploaded - Size - Downloads - 18870 - SoB Adult helght.jpg - admin 26 Nov, 2022 - 33.43 Kb - 637 - 18869 - SoB menarch.jpg - admin 26 Nov, 2022 - 34.73 Kb - 619 - 18868 - SoB Biobank 2015.pdf - admin 26 Nov, 2022 - 290.35 Kb - 460 - 18867 - SoB Schizophrenia.jpg - admin 26 Nov, 2022 - 29.29 Kb - 672 - 14692 - Season of birth vs longevity draft.pdf - admin 10 Dec, 2020 - 481.31 Kb - 553