Research

GrassrootsHealth’s mission is based on research, both from the vitamin D scientist community and from our D*action cohort. Below are research papers published using data from our vitamin D replete community (average serum level of 44 ng/ml vs. the general population’s 25 ng/ml) and papers published by GrassrootsHealth in association with other scientists in the field. For more research, you will find papers associated with every condition listed in the sidebar.

Maternal 25(OH)D concentrations ≥40 ng/mL associated with 60% lower preterm birth risk among general obstetrical patients at an urban medical center (Jul 2017)


Maternal 25(OH)D concentrations ≥40 ng/mL associated with 60% lower preterm birth risk among general obstetrical patients at an urban medical center


Sharon L. McDonnell

MPH et al. PLOS One

July 2017

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Serum levels greater than 40 ng/ml are associated with > 65% lower risk of cancer. (Apr 2016)


Serum 25-Hydroxyvitamin D Concentrations ≥40 ng/ml are Associated with >65% Lower Cancer Risk: Pooled Analysis of Randomized Trial and Prospective Cohort Study


Sharon L. McDonnell

MPH et al. PLOS One

April 2016

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Post-hoc Analysis of Vitamin D Status and Reduced Risk of Preterm Birth in Two Vitamin D Pregnancy Cohorts Compared with South Carolina March of Dimes 2009-2011 rates (Oct 2016)


Post-hoc Analysis of Vitamin D Status and Reduced Risk of Preterm Birth in Two Vitamin D Pregnancy Cohorts Compared with South Carolina March of Dimes 2009-2011 rates


Serum levels greater than or equal to 40 ng/ml decrease pregnancy comorbidities.

Carol Wagner

et al. Medical University of South Carolina

October 2015

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Incidence Rate of Type 2 Diabetes is >50% Lower in GrassrootsHealth Cohort with Median Serum 25-hydroxyvitamin D of 41 ng/ml than in NHANES Cohort with Median of 22 ng/ml (Jul 2015)


Incidence Rate of Type 2 Diabetes is >50% Lower in GrassrootsHealth Cohort with Median Serum 25-hydroxyvitamin D of 41 ng/ml than in NHANES Cohort with Median of 22 ng/ml


Serum levels over 40 ng/ml are associated with a 60% lower risk of type 2 diabetes.

Sharon L. McDonnell, MPH

et al. The Journal of Steroid Biochemistry and Molecular Biology

July, 2015

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Sunlight and Vitamin D: Necessary for Public Health (Jun 2015)


Sunlight and Vitamin D: Necessary for Public Health


Carole A. Baggerly, BA

et al. Journal of the American College of Nutrition

June, 2015

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Letter to Veugelers, P.J. and Ekwaru, J.P., A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D (Mar 2015)


Letter to Veugelers, P.J. and Ekwaru, J.P., A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D


9600 IU/day vitamin D, from all sources, is necessary to get 97.5% of the world up to 40 ng/ml.

Robert Heaney, MD

et al. Nutrients

March 2015

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Post-Hoc Comparison of Vitamin D Status at Three Time Points During Pregnancy Demonstrates Lower Risk of Preterm Birth with Higher Vitamin D Closer to Delivery (Nov 2014)


Post-Hoc Comparison of Vitamin D Status at Three Time Points During Pregnancy Demonstrates Lower Risk of Preterm Birth with Higher Vitamin D Closer to Delivery


25(OH)D values closer to delivery were more strongly correlated with gestational age at delivery than earlier values.

Carol L. Wagner, MD

et al. Journal of Steroid Biochemistry & Molecular Biology

November, 2014

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Meta-Analysis of All-Cause Mortality According to Serum 25-Hydroxyvitamin D (Aug 2014)


Meta-Analysis of All-Cause Mortality According to Serum 25-Hydroxyvitamin D


Serum 25(OH)D concentrations less than or equal to 30 ng/mL were associated with higher all-cause mortality than concentrations greater than 30 ng/mL.

Cedric F. Garland, DrPH

et al. American Journal of Public Health

August 2014

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25(OH)D Serum Levels May Provide Additional Reduction in Breast Cancer Risk (Apr 2014)


25(OH)D Serum Levels May Provide Additional Reduction in Breast Cancer Risk


Serum levels of 40-60 ng/ml may provide a significant reduction in breast cancer risk.

Sharon L. McDonnell, MPH

et al. American Society for Nutrition Scientific Sessions and Annual Meeting

April 2014

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Quantifying the food sources of basal vitamin D input. (Nov 2013)


Quantifying the Food Sources of Basal Vitamin D Input


Sharon L. McDonnell, MPH

et al. Journal of Steroid Biochemistry and Molecular Biology

November 2013

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Quantifying the non-food sources of basal vitamin D input. (Nov 2013)


Quantifying the Non-Food Sources of Basal Vitamin D Input


Sharon L. McDonnell, MPH

et al. Journal of Steroid Biochemistry and Molecular Biology

November 2013

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25-Hydroxyvitamin D in the Range of 20 to 100 ng/ml and Incidence of Kidney Stones (Oct 2013)


25-Hydroxyvitamin D in the Range of 20 to 100 ng/ml and Incidence of Kidney Stones


Serum levels from 20-100 ng/ml have no association with kidney stones.

Stacie Nguyen, MPH

et al. American Journal of Public Health

October 2013

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A Novel Approach Localizes the Association of Vitamin D Status With Insulin Resistance to One Region of the 25-Hydroxyvitamin D Continuum (May 2013)


A Novel Approach Localizes the Association of Vitamin D Status With Insulin Resistance to One Region of the 25-Hydroxyvitamin D Continuum


Study finds vitamin D status is inversely associated with insulin responsiveness and blood pressure.

Robert P. Heaney, MD

et al. Advances in Nutrition

May 2013

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All-Source Basal Vitamin D Inputs are Greater Than Previously Thought and Cutaneous Inputs are Smaller (Mar 2013)


All-Source Basal Vitamin D Inputs are Greater Than Previously Thought and Cutaneous Inputs are Smaller


Study finds basal (standard, non-supplemental) vitamin D intake approximately 2000 IU/day, not the 300 IU/day previously taught in medical school.

Robert P. Heaney, MD

et al. The Journal of Nutrition

March 2013

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Vitamin D Supplement Doses and Serum 25-Hydroxyvitamin D in the Range Associated with Cancer Prevention (Jan 2011)


Vitamin D Supplement Doses and Serum 25-Hydroxyvitamin D in the Range Associated with Cancer Prevention


Cedric F. Garland, Dr PH FACE

et al. Anticancer Research

January 2011

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