Vitamin D3 Deficiency Is A Silent Epidemic, Says Expert; How To Prevent

NDTV

22-07-2025

Lifestyle coach Luke Coutinho believes that the one vitamin most people are deficient in is vitamin D3. In a video on Instagram, he explains, "Almost one in one person I come across has a deficiency in vitamin D3. This is a silent epidemic. Yes, it is serious. In our world, there are over estimated billion people and more that have low vitamin D3."
He captions the video by mentioning that we often discuss hormones, bone density, immunity, mental health and metabolism, but overlook the major foundational player - Vitamin D3.
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Luke Coutinho revealed that the "sunshine vitamin" functions more like a hormone - influencing almost every cell in the body, including those involved in insulin sensitivity, sex hormone regulation (estrogen, progesterone, testosterone) and even neurotransmitter production.
In the video, he explains, "Low vitamin D3 affects people from the time they're kids, teenagers, adults and senior citizens in many, many ways. It's not just about brittle bones. It's not just about low energy levels. Vitamin D3 is a sex hormone playing a massive role in your overall hormonal health. Your progesterone, your estrogen, your testosterone and even your insulin sensitivity."
Luke Coutinho continues, "You will notice that in patients who have insulin resistance, insulin sensitivity, they always have low vitamin D3 levels. And by correcting that level through sunlight, through food, and mainly supplementation."
In the caption, the lifestyle guru further explains that low D3 levels during the formative years in children and teens can affect bone growth, mental health, mood swings, height and hormone balance. Additionally, he mentions that low levels in adults give rise to autoimmune conditions, chronic fatigue, anxiety, hair fall, infertility and even metabolic syndromes.
According to Luke, "a casual stroll in the morning sun may no longer be enough," as he shares, "The humans have messed up our climate. We've messed up our ozone layer. We don't even have the right amount of UVB rays hitting our skin, which is the magic sunshine that helps us with vitamin D3. So, yep, you're going to have to go to your doctor, kids, teenagers, and senior citizens, and make sure that you supplement the right way."
He also writes, "Before you invest in exotic supplements or strict diets, look at your basics: D3, B12, Iron, Magnesium, Thyroid and Gut health markers. Your body doesn't thrive on complexity-it thrives on consistency with fundamentals."
Luke Coutinho further mentions that the optimal reference range for D3 should be 30 to 100, and the best is within the range of 70 to 80 ng/mL (within a safe range of 30-100), that too under medical supervision. The celebrity lifestyle expert also advises that one should not overdo it on D3, as this can become extremely toxic to the body, especially the kidneys and other bodily organs. He clarifies, "The patients who come to us with critical levels, their D3 is at 5, 6 and 7. Within 10 to 15 days of starting to push their D3 up, most of their symptoms start to get better. You cannot ignore the basics."
In his concluding note, Luke mentions, "D3 is basic, but ignoring it is a big mistake."
Disclaimer: This content including advice provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.