Vitamin D Expert: The Supplement World Is Giving The WRONG Advice! · The Diary Of A CEO with Steven Bartlett summary

Key takeaways

Vitamin D functions as a hormone critical for sleep regulation and immune health, not just a vitamin.
Modern indoor lifestyles, reliance on artificial light, and certain diets have disrupted our natural vitamin D production and microbiome function, leading to widespread chronic health issues.
Gut bacteria produce B vitamins, which are essential for cellular repair, sleep, and overall health; deficiencies relate to sleep problems and autoimmune diseases.
Personalized supplementation of vitamin D and B vitamins, guided by blood testing, is safer and more effective than blanket recommendations.
Lifestyle changes such as increased sunlight exposure and incorporating fermented foods can restore microbiome health and improve sleep.
Indiscriminate use of supplements can cause harm; understanding individual needs and monitoring levels is vital.
Addressing deficiencies and microbiome health can prevent or reverse many modern chronic health disorders, including sleep disorders, obesity, depression, and autoimmune diseases.

Summary

The Misinformation in Vitamin and Sleep Science

Dr. Stasha Gominak discusses how many commonly accepted beliefs about vitamins, especially vitamin D, and sleep are incorrect or oversimplified. She emphasizes that vitamin D is actually a hormone, not a vitamin, and highlights how modern indoor lifestyles—due to artificial lighting, sunscreen, and air conditioning—have significant impacts on our natural sleep and health. She challenges the traditional medical approach that focalizes on behavioral sleep interventions and instead points to biochemical and microbiome-related causes of sleep problems and associated diseases.

Vitamin D as a Critical Hormone in Sleep and Disease

Gominak shares her hypothesis that vitamin D deficiency is directly linked to sleep disorders, immune problems, and chronic diseases like diabetes and cardiovascular issues. She explains the biological pathways, including vitamin D’s role in producing acetylcholine—a neurotransmitter vital for sleep regulation—via receptors in the brainstem. She advocates for personalized vitamin D dosing based on blood levels, emphasizing that supplementing without regard to individual needs can be harmful. She also explores sunlight’s role in producing vitamin D and other health-beneficial wavelengths like infrared light.

Gut Microbiome and B Vitamins in Sleep Physiology

A significant portion of the discussion focuses on the gut microbiome’s role in producing B vitamins essential for cellular repair and sleep regulation. Dr. Gominak posits that modern diets and reduced sunlight exposure have impaired microbiome function, leading to deficiencies that manifest as sleep problems, autoimmune diseases, and metabolic disorders. She emphasizes that B vitamins are bacterial growth factors, crucial for the microbiome’s health, and suggests that short-term supplementation can jumpstart microbiome repair, after which the body can support itself.

The Impact of Modern Lifestyle on Health and Sleep

The conversation highlights how indoor living, artificial lighting, and specific diets have disrupted our evolutionary sleep biology and microbiome. Dr. Gominak worries that chronic deficiency in vitamin D and B vitamins due to these factors contribute to widespread health issues, including obesity, depression, and autoimmune diseases. She advocates for lifestyle changes like more outdoor time, fermented foods, and tailored supplementation to restore natural biochemistry instead of relying solely on pharmaceuticals.

Correcting Misconceptions and Controversies in Supplement Use

Throughout the episode, Dr. Gominak criticizes the medical and supplement industries for cultural and regulatory reasons, pointing out that many guidelines are based on flawed studies or political influences. She warns about the dangers of indiscriminate supplement use—particularly vitamin D, B vitamins, and others—arguing that these can create deficiency states if not properly managed. She promotes a personalized approach, monitoring blood levels, and correcting deficiencies temporarily to restore microbiome health and sleep function.

Practical Advice for Improving Sleep and Health

The core message is that behavioral changes are a good first step, but addressing biochemical deficiencies—specifically vitamin D and B vitamins—is essential for those with chronic sleep issues or health problems. Dr. Gominak’s 'Right Sleep Protocol' involves individualized supplementation based on blood tests, emphasizing the importance of sunlight, diet, and microbiome health. She encourages keeping logs of symptoms and response to treatment, and suggests that holistic lifestyle adjustments can bring about profound health improvements.

Show notes

Nearly 1 in 3 American adults now take vitamin D, but Dr. Stasha Gominak says many of them are taking it wrong, and that done carelessly, supplementing can leave you worse off than before.

Dr. Stasha Gominak practiced neurology for over 20 years. She earned her MD from Baylor College of Medicine and completed her neurology residency at the Harvard-affiliated Massachusetts General Hospital. After working with her own patients, she believes that nearly everyone struggling to sleep shares the same hidden deficiency, a conclusion she published in 2 papers and built into RightSleep, the method she now teaches full time.

She explains:
◼ Why she believes your skin is the best producer of vitamin D, and why she says no amount of pills or salmon can replace it
◼ Why she believes insomnia isn't a behavior problem but a chemical deficiency, and what she thinks changed when we moved indoors
◼ The role she says your gut bacteria play in producing your B vitamins
◼ Why she believes taking vitamin D on its own can burn through your B vitamins, and what she says happened when she tried it herself
◼ Why she connects the rise in conditions like ADHD, depression, fatty liver and diabetes to the same period, and what she thinks links them
◼ Why she considers supplements a form of biohacking, and just as risky as any drug if you get them wrong

The views expressed are those of the guest, and this conversation is intended for general informational purposes only. This podcast and its associated materials should not be used as a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician before making any changes to your diet, supplements or health regimen.

Chapters

00:00:00 Intro
00:02:20 Why So Many People Are Suddenly Struggling With Sleep
00:03:22 Why Healthy Young People Are Waking Up Exhausted With Headaches
00:07:55 How Your Brain Secretly Controls Every Stage Of Sleep
00:15:15 How Vitamin D Could Be The Missing Piece For Better Sleep
00:20:42 Are Sleep Chronotypes Actually Real Or Just A Myth?
00:24:56 How Can You Prove Vitamin D Deficiency Causes Disease?
00:40:36 Why Vitamin D Isn't Actually A Vitamin
00:50:21 Ads
00:52:20 What Happened When I Started Treating Patients With Vitamin D
00:56:55 Does Vitamin D Deplete Your Body's B Vitamins?
01:00:26 Can Vitamin B Supplements Really Fix Your Gut?
01:14:38 Why Minerals Could Be The Overlooked Key To Better Health
01:15:25 Ads
01:16:34 Does Modern Medicine Accept This Vitamin D Theory?
01:19:43 What Your Gut Microbiome Reveals About Your Sleep
01:24:36 How To Build The Right Sleep Protocol For Better Rest
01:30:27 Is Sunlight And Nutrition Better Than Supplements?
01:34:37 Can Redheads Naturally Produce More Vitamin D?
01:36:44 Why Spending Too Much Time Indoors Is Hurting Your Health
01:39:47 Can You Still Make Vitamin D On Cloudy Days?
01:40:51 Can Vitamin D Lamps Replace Natural Sunlight?
01:42:43 The Best Diet To Boost Vitamin D And Improve Gut Health
01:48:47 What Actually Helps If You Have Sleep Apnoea Or Narcolepsy?
01:55:49 My Most Controversial Health Opinion Explained
01:57:50 The Best Day Of Your Life And Why It Matters

Independent Fact Check: https://stevenbartlett.com/wp-content/uploads/2026/07/DOAC-Dr-Stasha-Gominak-Independent-Research-Further-Reading.pdf

Dr. Stasha Gominak:
◼ RightSleep - https://link.thediaryofaceo.com/Gmn0oAj
◼ YouTube - https://link.thediaryofaceo.com/EqV6qH3
◼ Instagram - https://link.thediaryofaceo.com/20mY5VF
◼ Facebook - https://link.thediaryofaceo.com/GTUovlV

The Diary Of A CEO:
◼ Join DOAC circle here - https://doaccircle.com/
◼ Buy The Diary Of A CEO book here - https://smarturl.it/DOACbook
◼ The 1% Diary is back - limited time only - https://bit.ly/3YFbJbt
◼ The Diary Of A CEO Conversation Cards - https://linkly.link/2hm7r
◼ Get email updates - https://bit.ly/diary-of-a-ceo-yt
◼ Follow Steven - https://g2ul0.app.link/gnGqL4IsKKb

Sponsors:
Shopify - https://shopify.com/bartlett
Linkedin Talent Solutions - http://linkedin.com/DOAC