Many South Valley residents insist eating fresh garlic is
healthy for the heart. Stanford University is now working on a $1.5
million federally funded research study to determine if that claim
is true.
Many South Valley residents insist eating fresh garlic is healthy for the heart. Stanford University is now working on a $1.5 million federally funded research study to determine if that claim is true.
About 220 Bay Area volunteers are participating in the study, eating specially prepared gourmet sandwiches six days a week for a period of six months, said Lorraine Chatterjee, research coordinator with the Stanford Prevention Research Center. Some of the sandwiches contain smashed fresh Gilroy-grown garlic while others do not.
“The study is based on a double-blind, randomized placebo-controlled clinical trial,” she said.
This means both researchers and volunteers don’t know who gets the garlic. Volunteers are randomly picked to receive either garlic or non-garlic sandwiches during the course of the study. Each volunteer also receives a pill – either a real garlic capsule or a “placebo” (a non-garlic supplement used to factor in the mind’s influence on the pill’s effectiveness).
“An assistant knows who’s getting the garlic,” Chatterjee said. “What happens, the way we have designed the sandwiches is that they’re so flavorful that some people don’t know what (kind of) sandwich they’re getting.”
Sometime before Gilroy’s Garlic Festival next year, the center’s Nutrition Studies Group will release the results on its testing of the effects of fresh garlic on mildly elevated blood cholesterol and other related risk factors for heart disease, she said. The research is being paid for by a grant from the National Institute of Health’s National Center for Complementary and Alternative Medicine.
Volunteers are not paid. They range between 30 to 65 years in age, are non-smokers, non-diabetic and not pregnant or lactating. They also can not be taking any cholesterol
About 150 pounds of the “early California harvest” garlic was specially picked in Gilroy last summer. Researchers mashed it up into a paste. Before putting it on the sandwiches, they keep this mash in a special minus 80 degree freezer to maintain the chemical integrity of the “allicin,” the active ingredient in garlic that gives it its flavorful bite.
“Every six months, we send out a few samples to the biochemist who is working with us,” Chatterjee said. “He tests that to see if there’s any deterioration in the allicin.”
Stanford’s Christopher Gardner is the principal investigator in the garlic study. He received his doctoral degree in nutrition sciences from the University of California, Berkeley.
The idea for the garlic study was born about five years ago, he said. A supplement company paid him to research their commercially available garlic pill to determine its health benefits.
“They gave people the garlic (pill), and it didn’t lower their cholesterol,” he said.
A chemist named Larry Lawson contacted Gardner and told him the problem was in the yield of the allicin inside the pills. Much of the allicin is destroyed during the manufacture of the capsules.
“Garlic is really more complicated than people realize,” Gardner said. “You have to make the allicin before you swallow it.”
A chemical process takes place when fresh garlic is chewed in the mouth or mashed. An enzyme converts the chemical “alliin” into the active allicin in about six seconds.
The garlic in the Stanford study must be fresh and uncooked because the heat from cooking can destroy allicin and neutralize any potential benefits, Gardner said. His current study is the first to compare fresh garlic with pills to determine the effectiveness in lowering cholesterol. The two top-selling commercial supplements are being put up against the fresh garlic. In order not to jeopardize the study, Gardner can not reveal the brand names of the supplements.
People have claimed that garlic can lower blood pressure or act as an anti-inflammatory agent. However, the Stanford study will only look at the odorous herb’s effect on cholesterol levels.
Whatever results come in from this “scientifically rigorous” study, Gardner stressed the data should be analyzed with caution. “I’ve got a tiny piece of the puzzle,” he said. “It’s probably going to bring up more questions than it answers.”
Gardner suggested one day doing a study on how people actually eat garlic – such as on healthy stir-fried vegetables or on oily french fries – and how that influences any potential health benefits of the garlic.
“We don’t actually study it like people actually eat the food,” he said. “I’ll bet you half the benefit of garlic is the food that people eat it with. And that part gets left out because scientists think it’s too complicated.”
Although he has intensively studied the famous herb in a clinical environment, Gardner admits with a chuckle he’s never actually visited the Gilroy Garlic Festival held each July.
“I should go,” he said. “It’s just down the road.”
Gilroy farmer Don Christopher, one of the founders of the Garlic Festival, is greatly interested in whatever results come in from Gardner’s study. He strongly believes the researcher’s findings will show garlic does indeed lower cholesterol.
“They’re going to prove that if you use fresh garlic, it will thin the blood,” Christopher said. “I think they’ll prove all this. The problem with garlic is that it needs to be eaten fresh. When you cook it, it takes all the nutrients out of it.”
Christopher hopes a positive finding from the study will definitely benefit the South Valley’s garlic sales.
“The Japanese started using it in the 1970s, started writing about its benefits to the (body’s) system and energy,” he said. “That really helped the sales of garlic … We started the Garlic Festival and that (also) helped the sales of the garlic.”
Morgan Hill naturopath Rajesh Vyas also believes the Stanford study might prove cholesterol-lowering health benefits from garlic. He recommends his patients with high blood pressure or high cholesterol levels eat a fresh clove of garlic daily.
“Clinically, you can see it does work, and this kind of scientific validation is what people are really wanting,” he said.
Ultimately, whatever the results of the study, garlic is a delicious and inexpensive way to potentially improve a person’s health, said Stanford’s Chatterjee.
“You can’t go wrong,” she said. “What do you have to lose? A clove is not all that much to eat.”
Interested in more details on the Stanford garlic study? Visit www.news-service.stanford.edu/news/ 2003/january15/garlic.htlm.
