I have read statements such as "Fifteen pounds of wheatgrass is equivalent to 350 pounds of the choicest vegetables", of which I am obviously skeptical. Are there any independent studies from reputable sources about the benefits / risks of wheatgrass as part of a balanced diet? A standard google search reveals only a plethora of sites trying to sell wheatgrass and juicers.
Well, a student at Georgia Tech did an experiment on this, and some things noted are:
Claim: The chlorophyll in wheatgrass rebuilds the bloodstream. But in fact: Chlorophyll cannot affect the human body internally because it is not absorbed.
Claim: Wheatgrass contains enzymes, which aid our body in digestion. But in fact: Enzymes are produced by living organisms specifically for their own use. Plant enzymes are not the same as the enzymes produced by the human body. Furthermore, orally ingested enzymes are broken down in the stomach.
Claim: A 2 oz shot of wheatgrass has the same amount of vitamins and minerals as 4 pounds of vegetables. But in fact: Which vitamins and minerals? Which vegetables? This statement is too vague to be meaningful. For example, a 2 oz shot of wheatgrass juice only contains 15 mg of Calcium, as compared to 89 mg in a half cup of broccoli.
Claim: Wheatgrass cures cancer. But in fact: No scientific study has ever confirmed this.
For more information, I would recommend reading the National Council Against Health Fraud's Statement on Wheatgrass Therapy.
A television pilot for "Skeptologists" also covered wheatgrass. It was never aired, however the scientists and skeptics that were part of the cast maintain a blog, and several of them wrote about it. One of the members of the cast was Michael Shermer, author of Skeptic magazine (and neurologist specializing in how the brain believes things). He has written an article about wheatgrass as well:
According to William T. Jarvis, a retired professor of public health at the Loma Linda University School of Medicine and founder of the National Council against Health Fraud, this is all baloney: “Enzymes are complex protein molecules produced by living organisms exclusively for their own use in promoting chemical reactions. Orally ingested enzymes are digested in the stomach and have no enzymatic activity in the eater.” Jarvis adds, “The fact that grass-eating animals are not spared from cancer, despite their large intake of fresh chlorophyll, seems to have been lost on Wigmore. In fact, chlorophyll cannot ‘detoxify the body’ because it is not absorbed.”
That's not to say that this is BAD for you. It is vegetable matter, and as long as there are no poisons in it (which as far as I can tell there are none), it won't harm you. You will get benefits from this much like any other green leafy matter, depending on the actual contents of the wheatgrass (again, I point back that broccoli is healthier in terms of calcium for instance). Then there is the taste...
In other words, it's an outlandish claim that preys on ignorance of nutrition and biology.