The Vital Role of Vitamin D: 5 Essential Health Benefits

Published on March 12, 2025

Key Points

In this video, Dr. Suneel Dhand discusses how vitamin D benefits immunity, metabolism, heart health, muscle strength, and aging.
He explains that vitamin D boosts immunity by aiding antimicrobial peptide production, regulates insulin sensitivity to reduce diabetes risk, and supports cellular health by reducing inflammation and slowing aging.
Maintaining sufficient vitamin D levels lowers the risk of cardiovascular events, while supplementation enhances muscle performance and reduces falls in older adults.
Vitamin D is essential for immune and metabolic health.

In today’s featured video presentation, Dr. Suneel Dhand, an Internal Medicine physician, discusses the crucial role of vitamin D beyond just bone health. While many recognize its importance for the skeletal system, vitamin D has far-reaching effects on overall health, from immunity to metabolic function. Dr. Dhand shares his personal experiences growing up in England with low sun exposure and how supplementing with vitamin D transformed his well-being. He also highlights shocking vitamin D deficiency levels in hospitalized patients and the importance of maintaining optimal levels for health and longevity.

Watch the Video

Key Topics from the Video

0:00 – 1:01

Introduction to Vitamin D’s Importance

Dr. Dhand explains how he first learned about vitamin D’s impact on energy, mood, and immunity.
How supplementing with vitamin D improved Dr. Dhand winter health and reduced infections.

1:04 – 2:00

Vitamin D Deficiency: A Hidden Pandemic

Many hospitalized patients have dangerously low vitamin D levels, often in the single digits.
The modern lifestyle keeps people indoors, leading to widespread deficiency.
The further we move from natural sun exposure, the more negative the impact on our health.

2:03 – 2:55

Vitamin D and Immune Health

Vitamin D boosts immunity by promoting antimicrobial peptides that fight bacteria and viruses.
A British Medical Journal meta-analysis found that adequate vitamin D levels significantly reduce the risk of respiratory infections.
Studies during the pandemic reinforced vitamin D’s role in immune defense.

2:55 – 3:52

Vitamin D and Metabolic Health

Plays a key role in regulating insulin sensitivity and glucose metabolism.
Higher vitamin D levels are linked to a lower risk of type 2 diabetes.
A must-have for those managing weight, energy levels, and insulin resistance.

3:54 – 4:37

Anti-Aging and Longevity

Vitamin D reduces chronic inflammation, which accelerates aging.
Deficiency is linked to shorter telomeres, a marker of biological aging.
Maintaining optimal levels can contribute to healthier aging and longevity.

4:37 – 5:20

Vitamin D and Heart Health

Low vitamin D levels are associated with high blood pressure and heart disease.
Research shows that sufficient vitamin D reduces cardiovascular risks.
More than just bones—your heart needs vitamin D too.

5:20 – 6:10

Muscle Strength and Physical Performance

Supports muscle function and recovery, making it essential for athletes and aging adults.
Studies show that vitamin D supplementation improves muscle strength and reduces falls in older adults.

Is Your Vitamin D Level Optimized?

Vitamin D isn’t just about bones—it’s a foundational nutrient for overall health. The modern lifestyle makes it difficult to get enough from sunlight alone, so supplementation is often necessary. Whether you get it from the sun, diet, or supplements, maintaining optimal levels is key to supporting immunity, metabolism, heart health, and longevity. The GrassrootsHealth panel of vitamin D scientists and experts recommends a target vitamin D level of 40-60 ng/ml (100-150 nmol/L) for optimal health, with higher levels recommended for specific therapeutic benefits, such as those with autoimmune diseases and cancer concerns.

If you’re unsure of your vitamin D levels, consider getting tested and adjusting your intake accordingly.

Stay informed, stay healthy, and take charge of your vitamin D levels today!

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!

Build your custom kit here

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)

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