Hair fall, fatigue and mood swings: Apollo doctor warns you could be deficient in a crucial vitamin

A growing number of Indians are struggling with unexplained tiredness, hair fall, irritability and weakened immunity, and a leading specialist believes one silent culprit is often overlooked. Apollo Hospitals’ gastro surgeon Dr Anshuman Kaushal, widely known online as @theangry_doc, has issued a sharp reminder that Vitamin D is not merely a supplement but a pro-hormone that fuels essential body functions. In a recent Instagram post, he explained why deficiency is now widespread despite abundant sunlight.

The overlooked vitamin that controls mood and metabolism

In his video, Dr Kaushal said people frequently claim they get daily sunlight, yet their test reports show low Vitamin D levels. Speaking in a crisp, conversational tone, he warned that “sunlight through the window will not give you vitamin D, it will only give you illusion.” His post, titled “This tiny vitamin decides your mood, muscle and metabolism,” emphasised how deficiency can push the body into what he described as an energy saving state.

According to the doctor, Vitamin D works as a pro-hormone involved in the functioning of practically every cell, influencing bones, muscles, immunity, metabolic activity and even emotional stability.

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A post shared by Dr Anshuman Kaushal MD FACS (@theangry_doc)

Why sunlight alone may not be enough

Quoting from his explanation in the Instagram video, Dr Kaushal listed three major sources of Vitamin D: sunlight, food and supplements. He clarified that Ultraviolet B rays, which trigger Vitamin D production in the skin, are not present early in the morning. The most effective window is between 10 am and 3 pm when shadows are short and sunlight is strong.

However, modern lifestyles create barriers. Window glass blocks UVB rays, pollution filters sunlight and common habits like staying indoors, using SPF lotions above 35 or driving in tinted cars reduce natural exposure. “That is why 80 to 90 percent of people are deficient at some level,” he noted.

Food can help, but not completely

While natural sources such as salmon, tuna, egg yolk, mushrooms and fortified foods support Vitamin D intake, they usually cannot meet the body’s full requirement on their own. For many people, supplements become essential when sunlight is restricted by environment, lifestyle or weather conditions.

When to take supplements and how to get it right

Dr Kaushal explained that supplements are recommended when blood levels dip below 20 ng/ml. He advised choosing Vitamin D3 (cholecalciferol) over D2, typically prescribed at 60,000 IU once a week for six to eight weeks, followed by a maintenance dose every 15 to 30 days.

He stressed that Vitamin D must be taken with meals, ideally with healthy fats because it is a fat soluble vitamin. Pairing it with magnesium and Vitamin K2 improves long-term balance. At the same time, he cautioned against overuse, remarking that supplements are “more like love, do not overdose.”

A rising public health concern

As India becomes increasingly indoor oriented, deficiency of this vital nutrient is being detected across age groups, including office workers, young adults and even people living in areas with harsh tropical sun. For Dr Kaushal, the message is simple: pay attention to sunlight, food and supplements before the body begins to show signs of distress.

With symptoms ranging from low mood to fragile bones, he warns that ignoring Vitamin D levels can have lasting consequences. Early checks and small lifestyle shifts, he says, can protect long term health in a way most people underestimate.