Maturing sunflower head (Helianthus annuus) with bees. The central disk of the sunflower is surrounded by yellow ray florets. The disc florets start to mature from the outside edge inwards. Here only half the diameter has flowered. In the centre are the yellow unopened florets followed by the greenish immature florets in the middle. Each floret is capable of producing one seed and each head may have as many as 1 to 2000 seeds. Sunflowers are farmed for the seeds as a food for humans and animals and to produce an oil. Sunflower oil contains lecithin, tocopherols, carotenoids and waxes and has a high vitamin E content. It is a combination of mono-unsaturated and polyunsaturated fats with low saturated fat levels.