Lettuce is known for its rich antioxidant content. A new study has recently pointed out that lettuce varieties differ in their antioxidant effects though.
The research led by Usue Pérez-López of the Department of Plant Biology and Ecology of the UPV/EHU’s Faculty of Science and Technology is an exposé as to how the speed at which the compounds act is determined by the colour of the leaves of the vegetable: the antioxidants from lettuces with red leaves are faster in action than those with green leaves. The findings have been published in the Journal of Agricultural and Food Chemistry; the paper is entitled Phenolic Composition and Related Antioxidant Properties in Differently Coloured Lettuces: A Study by Electron Paramagnetic Resonance (EPR) Kinetics.
Lettuce consists of phenolic acids, flavonoids, anthocyanins, and vitamins A and C, all compounds known for carrying antioxidant properties, and thus effective at getting rid of free radicals that are harmful to the body because they trigger chain reactions that damage cell components. The compounds of three lettuce varieties – green-leaf ‘Batavia’, the semi-red-leaf ‘Marvel of Four Seasons’, and the red-leaf ‘Oak Leaf – were examined. By making use of Electron Paramagnetic Resonance (EPR) techniques, the kinetics of the compounds of each variety were observed.
The findings show that green-leaf lettuce consists of water-soluble, antioxidant compounds that act slowly and at moderate speed, while the red-leaf one has compounds with intermediate and rapid kinetics. The semi-red-leaf, on the other hand, include three kinds of compounds, with a rapid, intermediate and slow speed.
“The fact that there are compounds that act at different speeds does not mean that some are better or worse than others. If we eat foods that can generate free-radical activity, there will be some compounds that act to eliminate them more quickly. But at the same time, it is also important that our bodies should acquire foods with antioxidants that have slower kinetics so that the latter will continue to act over a longer period of time. That is why people say that it is very interesting to mix different types of lettuce because they have different, complementary characteristics,” explained Dr Pérez-López.
Make sure to have a variety of lettuce leaves in your salad!