Though it's been plentiful for thousands of years, grass has never been regarded as human food. It's tough, unyielding, and not very tasty.
Even Og the Caveman wouldn't have wanted to eat it. Cud-chewing animals known as ruminants maintain and operate several stomachs for the purpose of digesting grass.
But the juices of wheat grass and barley grass are now a craze at "health bars," and powdered grass is all over the supplements market. Wheat and barley grass are simply young plants before they've matured and produced the good grains we can actually consume and digest after they've been cooked.
Alfalfa, oat, rye, and other grasses are also being offered as juices or as supplements.
At many juice bars, you can have a shot of grass added to any drink you order. On the Internet you will find hundreds of sites extolling and, of course, marketing grasses in one form or another.
Astounding claims are made: grasses will cure diabetes, prevent heart disease, boost the immune system, detoxify the blood and the liver, cause wounds to heal, promote weight loss, and so on down the long list of anxieties and hopes typical of the sick and the well.
There is no scientific evidence to back up any of these claims.
Like other green plants, grass contains some vitamins and minerals -- beta carotene, vitamin C, and potassium -- but in very small amounts. By the time it's been processed for human consumption, it may contain only traces of nutrients.
Seven tablets of Pines Wheat Grass, for example, offer just 7 milligrams of vitamin C (the RDA is 90 milligrams a day). Juices, which are greatly diluted, may have even less.
As for antioxidants, you're better off eating a few spinach leaves. True, grass does contain chlorophyll, the pigment that plants use to convert sunlight into energy. Some plant pigments, such as beta carotene, are known to be beneficial to humans, but there is as yet no evidence that chlorophyll does anything for the human body. If so, there is plenty of it to be had in more palatable green plants.
There is no harm in taking a shot of wheat grass juice, but no benefit either. Most people think the stuff tastes pretty peculiar.
The supplements, often doctored up with a hodgepodge of bee pollen, herbs, algae, and other dubious ingredients, are a waste of money.
Instead, buy fresh produce, which your digestive tract was designed for. Nothing could be less natural, actually, than swallowing processed grass.
UC Berkeley Wellness Letter, 2004
Published 12 times a year, The University of California, Berkeley Wellness Letter is the only health letter to be top-rated by Money magazine and U.S. News & World Report as well as the Baltimore Sun and the Washington Post. To subscribe to the printed version click here.