May times people are concerned that the oxalates in spinach block the absorption of calcium. While this is true, it is of only minimal effect. Spinach is second only to kale in its ORAC value of antioxident activity and has amazing healing and health building effects. It also has great anti-inflammatory and anti-cancer activity.
Baby spinach leaves is best if you want to eat a raw salad. The leaves are more delicate. When cooking spinach, boil or steam for no more than a minute. This help activate the phytonutrients while not killing all the good stuff. Toss with a touch of good olive oil or raw butter to help absorb the fat soluable vitamins A and K. I also like to add a splash of raw apple cider vinegar or lemon juice!