- Lessons Learned from an RCT on Prenatal Vitamin D and Asthma - interview Feb 2025
- Asthma reduced 60% by daily 4,400 IU of Vitamin D while pregnant – RCT Feb 2024
- VitaminDWiki - 6 ways to reduce asthma risk even more:
- VitaminDWiki – Overview Asthma and Vitamin D contains
- 9 Relevant pages in VitaminDWiki
- VitaminDWiki Asthma and Vitamin D Receptor - many pages
Lessons Learned from an RCT on Prenatal Vitamin D and Asthma - interview Feb 2025
Summary by GLASP AI
- (00:00-01:34) Dr. Scott Weiss, a Harvard Medical School professor and top biomedical researcher, began studying vitamin D's role in asthma after identifying the vitamin D receptor gene's link to childhood asthma through genetic and observational studies.
- (03:07-04:26) Vitamin D has both endocrine effects
- (bone health, measured through serum levels) and developmental effects
- (immune system, organ development, measured in tissue levels).
- It plays a crucial role throughout pregnancy, from implantation to postnatal immune function.
- (04:26-08:49) The VDART trial enrolled pregnant women *(10-18 weeks gestation) at high risk for having asthmatic children, randomizing them to receive either 4,400 IU or 400 IU vitamin D daily. Results showed a 20% reduction in childhood asthma, with a p-value of 0.051.
- (13:09-15:13) The trial faced three main limitations: insufficient vitamin D dosing *(only 75% reached target levels), late pregnancy initiation, and the presence of vitamin D in both control and treatment groups at baseline. When these factors were accounted for through meta-analysis and stratification, the reduction in asthma risk increased to 50%.
- (27:32-29:08) Molecular and genetic evidence showed vitamin D influences fetal lung development by increasing sphingolipid levels, which are necessary for airway and immune system development. This provides mechanistic support for the clinical findings.
- (31:50-33:14) Vitamin D deficiency during pregnancy may be a significant contributor to health disparities, particularly affecting African-American communities. Current recommendations *(600 IU) are
- far below what experts like Dr. Weiss suggest *(6,000 IU minimum).
- (34:34-38:16) Pregnancy creates a dramatically increased physiological need for vitamin D, with 5-20 times higher requirements than non-pregnant state, due to fetal development needs and immune system modulation.
- (38:57-41:03) Dr. Weiss's team conducted mouse studies to measure vitamin D levels in various tissues compared to serum levels, as tissue measurements aren't possible in living humans. This research aims to better understand the relationship between serum and tissue vitamin D levels.
- (41:41-44:11) Dr. Weiss advocates for using "totality of evidence" rather than relying solely on randomized controlled trials for medical guidelines. He notes that BMI significantly affects vitamin D's effectiveness - women with normal BMI at pregnancy start showed better outcomes than obese women.
- (46:28-49:22) For future trials, Dr. Weiss recommends: enrolling women earlier in pregnancy *(4-5 weeks vs. 10-18 weeks), using higher vitamin D doses *(6,000-8,000 IU vs. 4,400 IU), and ensuring greater baseline difference between control and treatment groups. He notes VDART's results likely apply to general population.
- (50:04-52:54) While a new randomized controlled trial would cost approximately $10-12 million, Dr. Weiss considers this cost-effective given the potential lifetime savings from preventing pregnancy complications and childhood health issues. The main challenge is finding initial funding for such a study.
Asthma reduced 60% by daily 4,400 IU of Vitamin D while pregnant – RCT Feb 2024
Association of Prenatal Maternal and Infant Vitamin D Supplementation with Offspring Asthma
Ann Am Thorac Soc Vol 21, No 2, pp 279–286, DOI: 10.1513/AnnalsATS.202306-504OC
Lourdes G. Ramirez 1,2, Kathleen Lee-Sarwar1,2, Rachel S. Kelly1,Scott T. Weiss1, and Augusto A. Litonjua3
1Channing Division of Network Medicine and
2Division of Allergy and Clinical Immunology,
both 1&2: Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts;
3Division of Pediatric Pulmonary Medicine, Golisano Children’s Hospital at Strong, University of Rochester Medical Center, Rochester, New York
Rationale: The role and timing of vitamin D supplementation in the prevention of asthma has not been fully elucidated.
Objective: To describe the association between prenatal and postnatal vitamin D with offspring asthma outcomes in participants of the Vitamin D Antenatal Asthma Reduction Trial.
Methods: We classified 748 mother-offspring pairs into four groups based on the mother’s randomization to receive high-dose versus low-dose (4,400 IU vs. 400IU) vitamin D supplementation during pregnancy and the offspring parent-reported highdose versus low-dose (>400 IU vs. <400 IU) vitamin D supplementation as estimated by intake of vitamin D drops or infant formula. We used logistic regression to test the association of the four vitamin D exposure groups—“mother-low/infant-low (reference),” “mother-high/infant-high,” “mother-high/infant- low,” and “mother-low/infant-high”—with offspring asthma and/or recurrent wheeze at age 3 years, active asthma at age 6 years, and atopic asthma at age 6 years.
Results: The risk of asthma and/or recurrent wheeze at 3 years was lowest in the mother-high/infant-low group (adjusted odds ratio vs. mother-low/infant-low, 0.39; 95% confidence interval, 0.16-0.88, P = 0.03). When stratifying by history of exclusive breastfeeding until age 4 months, the protective effect in the mother-high/infant-low group was seen only among exclusively breastfed infants (odds ratio vs. mother-low/infant-low, 0.19; 95% confidence interval, 0.04-0.68; P = 0.02). We did not observe any significant associations with active or atopic asthma at age 6 years.
Conclusions: We observe that high-dose prenatal and low-dose postnatal vitamin D supplementation may be associated with reduced offspring asthma or recurrent wheeze by age 3 years, but this association may be confounded by the protective effect of breastfeeding.
Download the PDF from VitaminDWiki
VitaminDWiki - 6 ways to reduce asthma risk even more:
- Higher dose (author reccomends 6,000 IU)
- Provide even higher doses for mothers who smoke
- Start before she typically realizes that she is pregnant
preferably start BEFORE conception (author recommends 4-5 weeks after) - Use a loading dose
- Use weekly dosing in place of daily
- Also use Vitamin D Receptor activator
VitaminDWiki – Overview Asthma and Vitamin D contains
- VitaminDWiki pages containing ASTHMA in title (164 as of Nov 2024)
- Asthma attacks reduced in half if Vitamin D level higher than 42 nanograms – RCT May 2014
- Started with 100,000 IU loading dose and has standard-of-care Asthma drug
- Asthma may be treated by Vitamin D if more than 40 ng for 12 months – Sept 2018
- Those with Asthma or COPD had half the response to Vitamin D – March 2020
- Those with Asthma need larger doses to get the same response.
- Probably need gut-friendly Vitamin D
- CDC funded study: 1.3 X Asthma risk if vaccination contained aluminum – Sept 2022
- Asthma occurrence rate reduced 3X by Vitamin D – 8 study meta-analysis - Aug 2021
- Asthma in child 2.3 X more likely if both parents asthmatic (unless add Vitamin D) – VDAART Nov 2018
- Adult-onset asthma 2X more likely if low vitamin D and not hyperallergenic – May 2018
- Children had poor lung function if mothers had low vitamin D while pregnant – Nov 2022
- 26 health factors increase the risk of COVID-19 – all are proxies for low vitamin D
- CDC list of high-risk for COVID-19 includes Asthma
- Child Asthma increased 2.1 X by antibiotics, Child milk allergy increased 4.4 X by PPI – April 2018
- Asthmatic children taking Corticosteroids had 2X more vitamin D intake, but lower levels – July 2017
- Traffic pollution increases asthma unless supplement with Vitamin D (mice) June 2018
- Childhood asthma problems eliminated for months by 600,000 IU of Vitamin D injection – June 2017
- Proof that Vitamin D Works 99 health problems prevented/treated as of Feb 2025
- Asthma has been proven to be treated by Vitamin D in at least 4 random controlled trials
- Childhood asthma still reduced 4 months after 800 IU of Vitamin D daily - RCT Feb 2016
- Respiratory Disease exacerbations (Asthma, CF, COPD) may be treated by Vitamin D – July 2019
- Women with asthma 35X more likely to be vitamin D deficient – Oct 2013
- If high vitamin D during pregnancy the child is 5X less likely to get asthma
- Asthma is treated by Vitamin D – now they are trying to understand why – Feb 2015
- Increase in vitamin D deficiency may partially explain increases in asthma and allergies – Jan 2015
- Why deficiencies in vitamin D and magnesium are linked to asthma Magnesium allows muscles to relax
- Babies 3.6X more likely to go to hospital for asthma if asthmatic mother had low vitamin D while pregnant – June 2019
- The worse the bronchial asthma, the lower the vitamin D – Jan 2017 has the following chart
click on the chart to see the study
9 Relevant pages in VitaminDWiki
- Reduction of infant asthma may require good vitamin D when lung development starts (4 weeks) – March 2017
- Those with Asthma or COPD had half the response to Vitamin D – March 2020
- Risk of infant Asthma cut in half if mother supplemented Vitamin D to get more than 30 ng – RCT Oct 2017
- Vitamin D Deficiency is a Strong Predictor (4X) of Asthma in Children – Oct 2012
- Less Asthma if mother took vitamin D while pregnant – Oct 2023
- Asthma reduced 31 percent when Omega-3 taken during pregnancy – RCT Dec 2016
- Asthma in 3 year olds decreased somewhat with 4,000 IU during pregnancy – RCT Jan 2016
- Smoking while pregnant lowers vitamin D and increases child asthma by 3.6 X – Aug 2011
Smoking typically reduces vitamin D levels by 10 ng/ml