Skip to content

Cholesterol & Triglycerides Health Center

Garlic May Not Lower Cholesterol

Study Shows No Improvement in Cholesterol Levels From Raw Garlic or Garlic Supplements
Font Size
A
A
A

Garlic Study

The researchers included Stanford University's Christopher Gardner, PhD.

They gave participants sandwiches to eat and pills to take six days per week for six months.

Participants were split into four groups. One group got sandwiches that included four to six cloves of crushed raw garlic. They took sham supplements containing no garlic or other active ingredients (placebo pills).

Another group got garlic-free sandwiches and took Garlicin, a powdered garlic supplement.

The third group got garlic-free sandwiches and took Kyolic, an aged garlic supplement. The fourth group got garlic-free sandwiches and placebo pills.

Extensive tests show that all three forms of garlic contained comparable amounts of allicin, a compound studied for possible anticholesterol effects.

Participants had their cholesterol checked monthly throughout the six-month study.

Study's Results

None of the three forms of garlic affected participants' total cholesterol, LDL ("bad") cholesterol, HDL ("good") cholesterol, triglycerides, or other blood fats, the study shows.

"The lack of effect was compelling and clear," Gardner says in a Stanford news release. "The numbers just didn't move. There was no effect with any of these three products, even though fairly high doses were used."

He says the study was large enough and long enough to have detected any cholesterol changes.

"We even looked separately at the participants with the highest vs. the lowest LDL cholesterol levels at the start of the study, and the results were identical," Gardner says.

However, the researchers don't rule out the possibility that garlic has health benefits for other groups of people (such as those with higher LDL cholesterol levels) or requires higher doses.

Second Opinion

The study's results "do not demonstrate that garlic has no usefulness in the prevention of cardiovascular disease," write the editorialists.

They included Marcus McFerren, MD, PhD, of the Center for Complementary and Integrative Medicine at New York's Weill Cornell Medical College.

Many factors affect heart disease, and allicin may not be the only compound in garlic that affects cholesterol, the editorialists suggest.

Garlic supplements are probably safe (no side effects were seen in the study), write McFerren and colleagues. "Do they prevent cardiovascular disease? The jury is still out," the editorialists write.

Gardner's team didn't set out to see if garlic prevented heart disease. The study only tracked cholesterol and other lipid levels.

Is This Normal? Get the Facts Fast!

Is Your Cholesterol Level Heart Healthy?
What is your LDL (low-density lipoprotein) level?

Get the latest Cholesterol Management newsletter delivered to your inbox!


or
Answer:
Desirable
0-199
Borderline
200-239
High
240+

Your level is currently

Congratulations! Your total cholesterol level is in the Desirable range, and your level of "bad" LDL cholesterol is optimal.

Congratulations! Your total cholesterol level is in the Desirable range, and your level of "bad" LDL cholesterol is near optimal.

Your total cholesterol level is in the Desirable range, but your level of "bad" LDL cholesterol is borderline high. If your LDL goes higher, your total cholesterol level could become Borderline High. Consider reducing the amount of foods you eat with saturated fats and increasing physical activity. If you get more exercise, your level of "good" HDL cholesterol may increase, which could also help to keep your levels of LDL and total cholesterol in check.

Your total cholesterol level is in the Desirable range, but your level of "bad" LDL cholesterol is High. This may mean that your level of high-density lipoprotein (HDL), or "good" cholesterol, is too low. It is best to have a high level of "good" HDL and a low level of "bad" LDL. The HDL helps keep your LDL level in check. Ask your doctor for your HDL level. If your HDL is low, increasing your physical activity can increase it, which may help reduce your LDL level.

Your total cholesterol level is in the Desirable range, but your level of "bad" LDL cholesterol is Very High. This may mean that your level of high-density lipoprotein (HDL), or "good" cholesterol, is too low. It is best to have a high level of "good" HDL and a low level of "bad" LDL because the HDL helps keep your LDL level in check. Ask your doctor for your HDL level. If your HDL is low, increasing your physical activity can increase it, which may help reduce your LDL level.

Your total cholesterol level is Borderline High, but fortunately your level of "bad" LDL cholesterol is optimal. This could mean you have a high level of high-density lipoprotein, or "good" HDL cholesterol, which protects against heart disease. Or you could have other non-measured increases in LDL-like particles that can increase heart disease. Your LDL level also could be optimal if you are taking a statin medication. Please check with your doctor to get your complete lipid profile and see if you may need additional treatment. In the meantime, find more information on WebMD's Cholesterol Health Center.

Your total cholesterol level is Borderline High, but fortunately your level of "bad" LDL cholesterol is near optimal. This could mean you have a high level of high-density lipoprotein, or "good" HDL cholesterol, which protects against heart disease. Or you could have other non-measured increases in LDL-like particles that can increase heart disease. Your LDL level also could be optimal if you are taking a statin medication. Please check with your doctor to get your complete lipid profile and see if you may need additional treatment. In the meantime, find more information on WebMD's Cholesterol Health Center.

Your total cholesterol level is Borderline High. Your level of "bad" LDL cholesterol is Borderline High, too. Working to bring down your total cholesterol decreases your LDL cholesterol level. You can do this by exercising more and eating less food with saturated fats. Check food labels!

Your total cholesterol level is Borderline High. Your level of "bad" LDL cholesterol is High. Working to bring down your total cholesterol decreases your LDL cholesterol level. You can do this by exercising more and eating less food with saturated fats. Check food labels!

Your total cholesterol level is Borderline High. But your level of "bad" LDL cholesterol is Very High. Working to bring down your total cholesterol decreases your LDL cholesterol level. You can do this by exercising more and eating less food with saturated fats. Check food labels!

Your total cholesterol is High, but your level of "bad" LDL cholesterol is optimal. This could mean you have a high level of high-density lipoprotein, or "good" HDL cholesterol, which protects against heart disease. Or you could have elevated secondary lipids, such as non-HDL particles that increase the risk of heart disease. Your LDL level also could be optimal if you are taking a statin medication. Please check with your doctor to get your complete lipid profile and see if you may need additional treatment. In the meantime, find more information on WebMD's Cholesterol Health Center.

Your total cholesterol is High, but your level of "bad" LDL cholesterol is near optimal. This could mean you have a high level of high-density lipoprotein, or "good" HDL cholesterol, which protects against heart disease. Or you could have elevated secondary lipids, such as non-HDL particles that increase the risk of heart disease. Your LDL level also could be optimal if you are taking a statin medication. Please check with your doctor to get your complete lipid profile and see if you may need additional treatment. In the meantime, find more information on WebMD's Cholesterol Health Center.

Your total cholesterol level is High. Your level of "bad" LDL cholesterol is Borderline High. Working to bring down your total cholesterol decreases your LDL cholesterol level. You can do this by exercising more and eating less food with saturated fats. Check food labels!

Your total cholesterol level is High. Your level of "bad" LDL cholesterol is High, too. Working to bring down your total cholesterol decreases your LDL cholesterol level. You can do this by exercising more and eating less food with saturated fats. Check food labels! If you are struggling to bring down your total cholesterol and LDL cholesterol levels, your doctor may prescribe medication, such as statins. Following medication, dietary, and exercise instructions should result in improvements.

Your total cholesterol level is High, and your level of "bad" LDL cholesterol is Very High. Working to bring down your total cholesterol decreases your LDL cholesterol level. You can do this by exercising more and eating less food with saturated fats. Check food labels! If you are struggling to bring down your total cholesterol and LDL cholesterol levels, your doctor may prescribe statins or other cholesterol-lowering medications.

Start Over

Step:  of 

Today on WebMD

woman pulling supplements from shelf
Can they help lower yours?
bowl of yogurt with heart shape
What it can do for you.
 
woman exercising
14 practical tips.
chocolate glazed donut and avocado
What your levels mean.
 
Heart Foods Slideshow
Slideshow
Cholesterol Fact or Fiction
Quiz
 
Food & Fitness Planner
TOOL
Attractive salad
ARTICLE
 
Heart Disease Overview Slideshow
SLIDESHOW
worst sandwich slideshow
SLIDESHOW
 
Fat Foods Fit Foods
SLIDESHOW
woman drinking coffee
SLIDESHOW
 

WebMD Special Sections