The spice of life


Onions away
It's hard to imagine, but there are people in India who shun onions and garlic, supposedly because these pungent bulbs promote lust. We don't know about lust, but we can understand craving garlic bread or juicy fried onion rings.

pucker upEasier to understand than these culinarily challenged folks is another sect in India whose members eat lots of onions and garlic. The blood of those bulb-bingers clots extremely slowly, indicating that onions, garlic or both contain something that slows clotting.

Blood clotting is a great thing when you're injured. But an unwanted clot in your brain is called a stroke, and a stroke can kill you. Similarly, a clot in your heart can cause the big pump to stop beating.

That's why scientists are so interested in stuff that prevents clotting. Taking a cue from those Indians who eat massive amounts of garlic and onions, and whose blood clots slowly, University of Wisconsin-Madison horticulturist Irwin Goldman has begun looking at chemicals called thiosulfonates that appear after onions are cut.

As with garlic, the chemical is released through a reaction between two chemicals that were once separated in the onion. But instead of looking at antibiotic properties, as David Mirelman of Israel is doing, Goldman is examining how the chemical affects the aggregation of platelets. Platelets are tiny particles in the blood that form a mesh in an early stage of blood clotting.

The bleeding edge
Using his own blood, and supplies donated by grad students, Goldman's team (including Murray Koppelberg, Jan Debaene and Kathryn Orvis) has shown that the thiosulfonates do inhibit the aggregation of platelets in laboratory dishes. The next step is to see if thiosulfonate works as well in animals as in plastic, when UW-Madison cardiologist John Folts drips the onion compounds into dogs stomachs. pucker up(Since raw onion causes anemia in dogs, they will be spared burgers with a slice of raw onion.)

It's unclear where the work is leading. The thiosulfonates could become the basis for a medicine that slows clotting. Alternatively, it could lead to renewed interest in the health benefits of eating raw onions.

But all that remains in the future, Goldman says. At present, he says, "We can't even say there's any value from a clinical point of view. We need to pin down exactly what compound is at work."

And there are other questions. Although tests show that the active chemical is destroyed by cooking, studies in India suggest that eating cooked onion can indeed slow clotting at times.

So garlic is healthy. So onion is healthy. Are you going to say the same thing about marinade?


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