fbpx

Published on November 17, 2025

What Should You Believe About Vitamin D Research?  Should You Follow the Recommendations? Join Us Tomorrow for Another Vitamin D Study Hour

Key Points

  • Dr. William Grant is a world-recognized expert in sunlight and vitamin D who will lead the next Vitamin D Study Hour webinar tomorrow, emphasizing that many vitamin D RCTs are flawed because they use drug-trial designs that do not reflect how nutrients work in the body.
  • Participants are encouraged to “Do Your Homework” by exploring Dr. Grant’s research, including his reviews on cardiovascular health, population guidelines, and the Disinformation Playbook used against vitamin D.
  • The webinar includes a short scientific review followed by live Q&A, and attendees can submit questions in advance for Dr. Grant or other upcoming speakers.

Measure Your Levels

William B. Grant, PhD (Physics, UC Berkeley, 1971).
Director, Sunlight, Nutrition and Health Research Center
San Francisco, CA

We are honored to welcome Dr. William Grant, who has been recognized as a world expert in sunlight and vitamin D, to our next Vitamin D Study Hour webinar with Q&A – scheduled for tomorrow, Wednesday November 19 at 2pm ET/11am PT.

Registration Closed – Watch the Recording Here

“One of the main obstacles to the acceptance of vitamin D is the fact that most vitamin D RCTs have been conducted based on the model for pharmaceutical drugs, not nutrients.” ~ Dr. William Grant

 

Do Your Homework!

Get a basic understanding about vitamin D, vitamin D research, the “Disinformation Playbook,” and more. We encourage you to “Do Your Homework!”

  1. Read Dr. Grant’s recent papers on evaluating vitamin D studies:
    Vitamin D and Cardiovascular Health: A Narrative Review of Risk Reduction Evidence
    Vitamin D: Evidence-Based Health Benefits and Recommendations for Population Guidelines
  2. Read the Commentary by Dr. Grant about the Disinformation Playbook here.
  3. Watch the video presentation by Dr. Grant, Vitamin D Latest Research 2025: Shocking Truths & Disinformation Exposed below.

A recent press release by Dr. Richard Cheng, titled “RCTs: The Foundational Flaw of Modern Medicine?” also touches on this and includes 19 recurring design flaws mentioned by Henry Lahore, an expert on vitamin D.

Read the press release here.

Submit your questions ahead of time for this or any one of our upcoming Vitamin D Study Hour webinars here:  https://www.grassrootshealth.net/submit-question-vitamin-d-scientists-medical-doctors/

Webinar Details, Q&A Submission & Sign-Up

Tomorrow!  Wednesday 11/19 at 11am PT, with Dr. William Grant.

Registration Closed – Watch the Recording Here

Vitamin D Study Hours will be held Wednesdays at 11am PT/2pm ET with a 15-20 minute review/presentation by the featured scientist, followed by questions and answers.  The expected time for each session is 30-40 minutes.

Donate Today

💛 Help Us Continue to Make a Global Impact! GrassrootsHealth is a nonprofit public health organization dedicated to promoting optimal health worldwide, with a primary focus on the role of vitamin D. Since 2007, we have teamed up with the world’s leading vitamin D researchers and experts to educate about vitamin D and to move vitamin D research into practice. Through evidence-based education, resources, tools, and our citizen-science approach to research (the D*action project), we empower individuals and practitioners alike to make informed and actionable decisions about their health and the health of their patients.

Donate Here

Thank you for supporting our mission and our ongoing commitment to vitamin D research, education, and advocacy!

Measure Your Vitamin D and Other Important Nutrients

If you haven’t had your vitamin D levels checked recently, now is the time! With so many Americans still falling short, awareness is the first step toward change.

Measuring and calculating a supplementation amount to help reach and maintain a target level, or taking loading doses to correct deficiency faster, could possibly make all the difference in overall health, wellbeing, and how a current disease situation progresses. Test your level now!

Create your custom home blood spot kit by adding any of the following measurements, along with your vitamin D:

Having and maintaining healthy vitamin D levels and other nutrient levels can help improve your health, now and for the future. Enroll and test your levels today, learn what steps to take to improve your status of vitamin D (see below) and other nutrients and blood markers, and take action! By enrolling in the GrassrootsHealth projects, you are not only contributing valuable information to everyone, you are also gaining knowledge about how you could improve your own health through measuring and tracking your nutrient status, and educating yourself on how to improve it.

How Can You Use this Information for YOUR Health?

Having and maintaining healthy vitamin D and other nutrient levels can help improve your health now and for your future. Measuring is the only way to make sure you are getting enough!

STEP 1 Order your at-home blood spot test kit to measure vitamin D and other nutrients of concern to you, such as omega-3s, magnesium, essential and toxic elements (zinc, copper, selenium, lead, cadmium, mercury); include hsCRP as a marker of inflammation or HbA1c for blood sugar health

STEP 2 Answer the online questionnaire as part of the GrassrootsHealth study

STEP 3 Using our educational materials and tools (such as our dose calculators), assess your results to determine if you are in your desired target range or if actions should be taken to get there

STEP 4 After 3-6 months of implementing your changes, re-test to see if you have achieved your target level(s)

Enroll in D*action and Build Your Custom Test Kit!