“The levels of beta-carotene in the Golden Lettuce leaves were up to 30 times higher than those of regular lettuce.”
The headline says vitamins. The lettuce has up to 30 times more beta-carotene, one antioxidant the body turns into vitamin A. Getting it there meant moving the pigment out of the chloroplasts, where too much of it chokes photosynthesis, plus treatments with high light intensity. “30 times more vitamins” is one nutrient in a lab.