Given the nickname of “The Stinking Rose”, garlic is actually a species of the onion family and is closely related to the onion, shallot, leek and chive. Garlic is a biennial herb and the bulb is a formed from a number of small bulbs called cloves. The tough papery skin of each clove is actually a protective leaf and they fit together neatly in the familiar dome. Some kinds of garlic peel easily, while the papery sheaths of others cling tenaciously. Size of the cloves is not indicative of flavor, though in general very large cloves are milder than small ones.
Throughout recorded history, garlic has been used for a variety of purposes. It was thought that the cultivation of garlic may date back to as far back as 2000 B.C. in China where its usage was primarily for providing energy to alleviating depression. Ancient Egyptians used garlic as currency, swore oaths on it and fed it to their slaves to increase their indurance and ward off illnesses. Many cultures used garlic as a way to fight off evil and evil creatures. Garlic definitely has an ecclectic history, so where does it stand today in regards to its medicinal uses as well as scientic evidence in support of these uses? Let’s find out as well get other information including Safety Issues and Interactions You Should Know About.
Medicinal Uses and Scientific Evidence for Garlic
Antimicrobial
- A double-blind study reported in 1999 found that a cream made from the garlic constituent ajoene was just as effective for fungal skin infections as the standard drug terbinafine.
- Raw garlic can kill a wide variety of microorganisms by direct contact, including fungi, bacteria, viruses, and protozoa as was seen in results from a 1996 study from Brown University School of Medicine and a 1990 Study from Murdock Healthcare.
Cancer Prevention
Studies suggest that regular intake of garlic as food or as aged garlic supplements may reduce risk of various forms of cancer by helping to strengthen the immune system.
- In 1994, the results of the Iowa Women’s Health Study showed that women who regularly consumed garlic, fruits and vegetables lowered their risk of developing colon cancer by 35%.
- The results from a 2000 study by the American Society of Clinical Nutrition and a 2007 Australian study by the Sanson Institute show that high intakes of garlic may be helpful in preventing colorectal or stomach cancer.
- There are also opposing studies stating that there still isn’t enough evidence that taking garlic can cut the risk of getting some cancers.
Cardiovascular Disease and High Cholesterol
- Some studies have reported that the consumption of garlic may lessen the progression of cardiovascular disease by helping to decrease LDL (bad cholesterol) while raising HDL (good cholesterol) while others disagree.
- In 2004, a Czech study found that the accumulation of cholesterol on the vascular walls of animals were reduced because of garlic supplementation.
- A Turkish study, also in 2004, showed that taking a garlic extract inhibited vascular calcification in human patients with high blood cholesterol.
Cold Prevention
The herb garlic has a long history of use for treating or preventing colds; however, there was no scientific evidence showing that it actually works for this purpose until just recently.
- The results from a 2001 UK Study showed that participants receiving garlic were almost two-thirds less likely to catch cold those receiving a placebo. Furthmore, participants who did catch cold recovered about one day faster in the garlic group as compared to the placebo group.
- In 2007, BBC News reported on a study that discovered that taking a daily garlic supplement reduced the risk of catching a cold by more than half.
Diabetes
- A study from the Institute of General Pathology and Pathophysiology which is in the Russian Academy of Medical Sciences in Moscow found preliminary evidence that that the use of garlic could enhance blood sugar control in diabetes. The results of this double-blinded placebo-controlled study demonstrated that the effects of time-released garlic powder tablets resulted in a lowering of the fasting blood glucose and serum triglyceride levels.
- Another study in India was successful in showing that garlic was almost as successful as a prescription drug and insulin in helping to manage one’s diabetic condition.
Infections
- Both a study in the UK and one in the US, done in 2005, have shown evidence that garlic could inhibit the growth of Candida Albicans. Candidad Albicans is a yeast that usually inhabits 80% of the human population without harmful effects; however, an overgrowth can also be a causal agent leading to various infections, digestive disorders as well as impacting the well-being of immunocompromised patients. The results of both these studies are promising, if not definitive.
Safety Issues
- As a commonly used food, garlic is on the FDA’s GRAS (generally recognized as safe) list. The only common side effect of garlic is unpleasant breath odor. Even “odorless garlic” produces an offensive smell in up to 50% of those who use it.
- When raw garlic is taken in excessive doses, it can cause numerous symptoms, such as stomach upset, heartburn, nausea, vomiting, diarrhea, flatulence, facial flushing, rapid pulse, and insomnia.
- Topical garlic can cause skin irritation, blistering, and possibly third-degree burns, so be very careful about applying garlic directly to the skin and by no means, should you put a garlic poultice on your bare skin because raw garlic can cause even more skin damage than just a topical cream.
- Since garlic might “thin” the blood, it is probably imprudent to take garlic pills immediately prior to or after surgery or labor and delivery, because of the risk of excessive bleeding. Similarly, garlic should not be combined with blood-thinning drugs, such as warfarin (Coumadin), heparin, aspirin, clopidogrel (Plavix), ticlopidine (Ticlid), or pentoxifylline (Trental). In addition, garlic could conceivably interact with natural products with blood-thinning properties, such as ginkgo, policosanol, or high-dose vitamin E.
- Garlic may also combine poorly with certain HIV medications and might also reduce the effectiveness of some drugs used for HIV.
Interactions You Should Know About
If you are taking:
- Blood-thinning drugs such as warfarin (Coumadin), heparin, aspirin, clopidogrel (Plavix), ticlopidine (Ticlid), or pentoxifylline (Trental): Do not use garlic except on medical advice.
- Ginkgo, policosanol, or high-dose vitamin E: Taking garlic at the same time might conceivably cause a risk of bleeding problems.
- Medications for HIV: Do not use garlic.
In Conclusion
There’s definitely a lot to this herb. Hopefully, some of the studies and information presented in this posting will make you want to learn more about garlic and how it could be beneficial for your health and well-being; however, before you put anything into your body, make sure that it’s not going to do more harm than good. Do the research, whether it’s doing your own reading or contacting either a medical or naturopathic doctor for more info. In the end, you’re the author of your own health story and we all want that story to have a happy ending.
Click to see iHerb’s selection of garlic products here. New to iHerb? Use Coupon Code WOW123 to get $5 off any first time order of $40 or less or $10 off any first time order of over $40.


Great article. I take garlic everyday, but I use a good quality supplemental form to avoid the odor. You are right that it helps in a multitude of health-related issues.
I have heard that in Germany, garlic is used as a naturla antibiotic, although I have nothing to back it up. I have also heard that it help in controling blood pressure.
Thanks for the great information.
Thanks for the comment, Marti. I’m glad that you found the information useful.
It truly is amazing how one herb can do so much, isn’t it?
Thanks for articel.
I would like to ask. I take 3-4 peaces of garlic with bread. Take as a sandwich. Maybe it is not good for me? Maybe i need to drink garlic pils?
Thanks?