A Long Time Ago:
Thousands of years ago, the ancient Egyptians noticed something amazing—eating liver could help people who couldn’t see well at night. This condition, called night blindness, made it hard to see in low light. A famous doctor named Hippocrates also recommended liver for eye problems, but back then, no one knew why it worked. They just knew it did.
The Big Discovery in the 1880s:
Fast forward to the 1880s, when a scientist named Snell figured out something important: cod liver oil could cure night blindness. He also discovered it helped with BitÖt’s spots, which are white patches on the eyes caused by not getting enough Vitamin A.
Rats, Butter, and a Breakthrough in the 1900s:
In the early 1900s, scientists were trying to understand why some foods made animals grow strong and healthy, while others didn’t. They fed young rats food that lacked certain nutrients, and the rats stopped growing. Then, in 1912, two researchers, McCollum and Davis, had a breakthrough: when they added butter, egg yolks, or cod liver oil to the rats’ diets, the rats became healthy again! They called this mystery nutrient “fat-soluble factor A”—what we now know as Vitamin A. Other scientists, like Osborne and Mendel, found similar results, confirming the discovery.
During this time, scientists also found another nutrient in foods like yeast and rice. They called it “water-soluble factor B”, now known as Vitamin B.
The Role of Plants in the 1920s:
By the 1920s, researchers turned their attention to plants. They discovered that the Vitamin A activity in plant foods came from a substance called carotene, which gives carrots, sweet potatoes, and other plants their orange color. They realized our bodies could convert carotene into Vitamin A, providing an essential source of the vitamin from plants.
The Final Piece in 1957:
The big question—how exactly does carotene turn into Vitamin A?—was finally answered in 1957. A scientist named Thomas Moore showed that our bodies transform carotene into Vitamin A. This discovery helped explain why eating colorful fruits and vegetables is so important for good health.
Why It Matters:
Vitamin A plays a vital role in keeping us healthy. It supports good vision (especially in dim light), helps our immune system fight off infections, and even aids in growth. Thanks to centuries of discoveries, we now know how important this vitamin is—and why it’s essential to eat a balanced diet rich in both animal and plant-based foods.
