When you compare the nutrition of red leaf lettuce vs. spinach vs. kale, guess who wins? Many are surprised to hear that red oak leaf lettuce has a substantially higher antioxidant value than the other two. Kale comes in at 1,770 and spinach measures out at 1,513. That means you're getting a staggering 40% more antioxidants with those reds!
Yet for some reason, you don't hear anyone talking about that. Maybe that's because the widely used red leaf lettuce, with its frilly edges and reddish-purple hue, has been taken for granted as too ordinary in the salad kingdom. Whatever the reason may be, it needs to change. By using this superfood, those red pigments are providing you with high levels of anthocyanins. That's a phytonutrient which has been researched for a plethora of health benefits.
For example, reportedly they have been shown to reduce cancer cell proliferation in both in vitro (in test tubes) and in vivo (in bodies) according to various studies. The same source cites research which suggests they may enhance night vision as well as overall vision, as demonstrated in both animal and human subjects. Other noteworthy studies mentioned are those which link anthocyanins being beneficial to cardiovascular health.
The journal Clinical Nutrition published a study in 2004 about rats being fed a diet of red leaf lettuce for a period of three weeks. The results? Their HDL (good) cholesterol went up and the rats' liver cholesterol levels plummeted by 41%.
Those on a diet will be happy to hear that 1 shredded cup of this lettuce only contains 4 calories. With that you also get 2098 IU's of vitamin A (42% of RDI) and 39.3 mcg of vitamin K (49% of RDI). Also, albeit in less impressive quantities, nearly 2 dozen other vitamins, minerals and nutrients.
Conclusion? There's nothing wrong with baby spinach, romaine lettuce, green leaf lettuce, or kale. All are great. But adding red leaf to your salad or sandwich provides high amounts of anthocyanins, a red flavonoid the others provide almost none of.
USDA Database for the Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods, Release 2 - Prepared by Nutrient Data Laboratory, Beltsville Human Nutrition Research Center (BHNRC), Agricultural Research Service (ARS), U.S. Department of Agriculture (USDA) - May 2010