There are food choices that are more powerful than others, but whether or not you get results has to be evaluated from a holistic perspective.
For example, you can always find an article that has good things to say about broccoli. Yet, look at all of the people who eat broccoli regularly who are still overweight, still getting heart attacks, still getting cancer etc.
If a person wants better health s/he has to fix their entire life: nutrition, sleep, exercise, environment, stress, etc.
IMHO drinking powdered tea leaves or powdered barley grass might be very healthy, but it will not be enough to override a poor diet, lack of vegetables, high stress levels, living near a fracking station, etc etc.