The Hidden Reason Vitamin D Fails in People with Obesity

Dr. Joseph Mercola - Take Control of Your Health

Briana Mercola

Alternative Health, Health & Fitness

4.6 • 1.6K Ratings

🗓️ 12 February 2026

⏱️ 5 minutes

🔗️ Recording | iTunes | RSS

🧾️ Download transcript

Summary

Extra body fat interferes with how vitamin D works after it enters your body, which explains why low levels often persist despite supplements or sun exposure
Vitamin D can become trapped in fat tissue and fail to convert into its usable form, leaving blood tests low even when intake appears sufficient
Deep belly fat and liver fat have the strongest impact on vitamin D availability, making waist size more important than body weight alone
Taking higher doses of vitamin D doesn't always fix the problem if metabolic signals from excess fat remain unchanged
Reducing visceral fat, restoring metabolic health, and supporting proper vitamin D activation help vitamin D function normally again

Transcript

Click on a timestamp to play from that location

0:00.0	Is your vitamin D still low even after sunshine and supplements?
0:04.0	And you're wondering what's blocking the benefits you expect.
0:07.0	Welcome to Dr. Mercola's cellular wisdom.
0:09.0	Stay informed with quick, easy-to-listen summaries of our latest articles,
0:13.0	perfect for when you're on the go.
0:15.0	No reading required.
0:16.0	Subscribe for free at Mercola.com for the latest health insights.
0:20.0	Hello, and welcome to Dr. Mercola's cellular wisdom. I'm Ethan Foster. Today we're
0:26.1	examining why vitamin D often underperforms when you carry extra body fat, why raising the dose
0:32.4	isn't a guaranteed fix, and how metabolic recovery changes the picture. Let's start with what researchers
0:38.4	found when they looked beyond simple intake in a scientific reports analysis of
0:43.0	452 people including vitamin D deficient obese adults, obese adults after
0:49.3	supplementation and healthy volunteers obese individuals showed less usable vitamin D even with similar
0:56.2	total stores. The vitamin D was entering, but activation lagged. There's also a conversion slowdown.
1:03.7	Your liver must turn incoming vitamin D into 25 hydroxyvitamin D before your kidneys make the fully
1:10.7	active form.
1:12.3	Obesity dampened the liver enzyme responsible for that first step.
1:16.3	So vitamin D stayed biologically inactive.
1:19.5	Short-lived D-2 and D3 moved through with roughly a 24-hour half-life,
1:24.1	while the longer-lasting 25 hydroxy form never accumulated as it should.
1:29.3	Location of fat matters, too.
1:31.3	A clinical nutrition study from the Netherlands Epidemiology of Obesity Cohort, 2,441 adults,
	...

Please login to see the full transcript.

Previous episode | Next episode

Disclaimer: The podcast and artwork embedded on this page are from Briana Mercola, and are the property of its owner and not affiliated with or endorsed by Tapesearch.

Generated transcripts are the property of Briana Mercola and are distributed freely under the Fair Use doctrine. Transcripts generated by Tapesearch are not guaranteed to be accurate.