Published on June 15, 2025
In this featured video, Dr. Renu Mahtani outlines the scientific foundation behind vitamin D’s role in immune regulation and its application in managing autoimmune disorders.
Key Points
- In this video, Dr. Renu Mahtani presents an overview of how vitamin D functions as an immunomodulator, particularly in the context of autoimmune conditions.
- She introduces the Coimbra Protocol, which involves personalized high-dose vitamin D therapy to help rebalance immune system function.
- The approach focuses on correcting both vitamin D deficiency and vitamin D resistance, with dosing guided by lab markers such as PTH (parathyroid hormone) and ionized calcium.
- Daily intake, regular monitoring, and supportive nutrients like magnesium are essential components of the protocol.
She explains how vitamin D goes beyond supporting bone health and serves as a key modulator of immune responses. The presentation emphasizes the importance of individualized therapy, as people with autoimmune diseases often have a degree of vitamin D resistance, requiring higher-than-standard doses to achieve therapeutic outcomes.
The video also introduces the Coimbra Protocol, developed by Dr. Cicero Coimbra, which uses specific clinical markers to tailor vitamin D dosing while ensuring safety through regular monitoring.
Watch the Video: “COIMBRA PROTOCOL: VITAMIN D THERAPY FOR AUTOIMMUNE DISORDERS – EXPLAINED BY DR. RENU MAHTANI MD FMNM”
Key Topics from the Video
0:00 – 1:00
Vitamin D as an Immune Regulator
- Acts selectively to reduce immune system overactivity without suppressing normal function.
- Important in addressing the underlying imbalance seen in autoimmune conditions.
1:01 – 3:00
Understanding Autoimmunity
- The immune system, present throughout the body, can become misdirected and target healthy tissues.
- The protocol addresses this at the cellular level.
3:00 – 7:30
T-Cells and Immune Balance
- Vitamin D increases T-regulatory cells (which reduce inflammation) and decreases TH17 cells (which drive autoimmunity).
- A balanced ratio between these cells supports immune tolerance.
7:30 – 9:00
Vitamin D Resistance
- Common in autoimmune patients due to genetic variations in vitamin D receptors.
- These individuals require higher daily doses to achieve immune benefits.
9:00 – 11:45
The Coimbra Protocol Overview
- Developed by neurologist Dr. Cicero Coimbra.
- Uses high-dose, daily vitamin D based on lab values to reduce immune dysregulation.
- Monitoring includes vitamin D, PTH, and ionized calcium.
11:45 – 14:00
Vitamin D and PTH Relationship
- PTH serves as a marker for how effectively vitamin D is working.
- As vitamin D becomes active in the body, PTH levels typically decrease.
- Dosing is adjusted based on this dynamic.
14:00 – 17:00
Calcium Considerations
- Vitamin D increases calcium absorption, so dietary calcium intake and hydration need to be managed.
- Monitoring ionized calcium helps avoid imbalances.
17:00 – 22:00
Monitoring for Safety
- High calcium—not vitamin D itself—is the primary concern in terms of toxicity.
- With proper monitoring, the risk is minimized.
22:00 – 25:00
Supportive Measures
- Exercise helps maintain bone strength, especially when using higher doses of vitamin D.
- Indian patients typically respond to lower doses than those seen in Western protocols.
25:00 – 29:55
Clarifying Vitamin D Toxicity
- Vitamin D toxicity is rare and typically linked to unmonitored, excessive calcium levels.
- Studies show that even levels up to 200 ng/mL are not associated with toxicity when calcium is properly controlled.
29:55-30:41
- Vitamin K2 Interactions
30:41-32:55
- Remission of autoimmune disease with vitamin D
Dr. Mahtani emphasizes that individualized dosing, regular testing, and dietary adjustments are key to safely implementing the Coimbra Protocol. This approach offers an evidence-informed alternative for patients with autoimmune conditions who may not respond well to conventional immunosuppressive therapies.
Learn more about the Coimbra Protocol with a more in-depth presentation by Dr. Coimbra here.
Consider working with a knowledgeable healthcare practitioner if you are interested in exploring therapeutic uses of vitamin D for the treatment of health conditions.
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How Are Your Levels of Vitamin D and Other Important Nutrients?
Check your vitamin D, omega-3s, magnesium, and other important markers today as part of the vitamin D*action project.
Measure your:
- Vitamin D
- Magnesium PLUS Elements (including zinc, copper, selenium, mercury, cadmium and lead)
- Omega-3 Fatty Acids
- hsCRP (for Inflammation)
- HbA1c (for Blood Sugar)
- and more
Did you know that each of the above can be measured at home using a simple blood spot test? As part of our ongoing research project, you can order your home blood spot test kit to get your levels, followed by education and steps to take to help you reach your optimal target levels. Start by enrolling and ordering your kit to measure each of the above important markers, and make sure you are getting enough of each to support better health and wellbeing!
Start Here to Measure Your Levels
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)
