Most of us don’t eat enough fruits and veggies, but with a broad and varied diet, nutrient deficiencies are relatively rare. However, billions of people on Earth don’t have the luxury of a broad and varied diet. Vitamin A deficiency, for instance, is a huge problem. An estimated 250,000-500,000 children who are vitamin A-deficient become blind every year, and half of them die within 12 months of losing their sight. Lettuce, one of the least attractive leafy vegetables, could end up playing a key role in this problem. A team of scientists from the Institute for Plant Molecular and Cell Biology …