Think you're eating healthy? Too much or too little of this everyday vitamin could raise your cancer risk, experts explain

Vitamin A has long carried a golden reputation, vital for sharp vision, strong immunity, and glowing skin. For years, it was even thought to shield the body from illnesses, including cancer. But science, as it often does, has revealed a twist: when it comes to vitamin A, too little and too much may both carry hidden risks.

What exactly is Vitamin A?

Vitamin A isn’t a single nutrient, but rather a family of fat-soluble compounds. You’ll find it in carrots, sweet potatoes, spinach, dairy products, and even liver. It plays a key role in cell growth and repair, making it central to the body’s defences against abnormal changes like tumour development.

Traditionally, more vitamin A was seen as better. But the latest research paints a more delicate picture. Think of vitamin A not as a straight road but as a tightrope: safe only when you walk the middle line.

What the new study discovered

As per a TOI report, researchers studied 3,758 cancer patients and 2,995 hospital controls, using detailed food questionnaires to assess vitamin A intake. The results were eye-opening:

• People consuming too little vitamin A nearly doubled their risk of developing cancer.
• Those taking in very high amounts also carried a similar risk.

The pattern formed what scientists call a U-shaped relationship. Both ends of the spectrum, deficiency and excess, raised danger, while the middle zone appeared safest.

The “sweet spot” for Vitamin A

The study suggested that the safest intake lies between 85.3–104.0 µg/day. Staying within this range was linked to the lowest risk of developing cancer.

This U-shaped trend appeared across several cancer types, including oesophageal, stomach, breast, and rectal cancers. Interestingly, it was not observed in lung or colon cancers. Even after adjusting for smoking, alcohol, and weight, the link held strong, showing it wasn’t a coincidence.

Why balance is everything

Nutrients work like puzzle pieces: missing one leaves gaps, but forcing in too many causes cracks. Vitamin A is no exception. Deficiency weakens the immune system, but overload can disrupt delicate cellular processes and cause damage instead of protection.

The real takeaway here isn’t to fear vitamin A or to rush out for supplements, but to respect balance. Vitamin A is neither a miracle cure nor a silent threat, it is a powerful nutrient that works best in moderation.

Inputs from TOI