garlic prevents colds - medically proven? no?

Factual Questions
1

I’m just starting this thread (but don’t have time the next few weeks to respond, rather maybe just to read any helpful responses):

The reason I’m asking whether garlic is medically proven to prevent or cure colds is because it actually has the opposite effect on me. It brings on a terribly raw throat, followed by nasal drip, and a full-fledged cold. But, then, mint jelly (consisting of spearmint oil) had the same effect on me too. (I also ate recently some spicy wheat snacks which had “seasonings” in the ingredients, & which had a similar effect.)

I also wonder what might cause this, and whether there’s any antidote so I can eat, say, garlicky pickles and the like, without repercussions.

Thanks in advance to anyone who might be capable of shedding some light on this mystery.

2

I consider myself a full-fledged herbal crackpot type. It was hard not to, my mom is the Queen of Herbal Crackpot types, so it rubbed off on the whole family.

She introduced garlic as a cure for colds (and other ailments) when I was kid, and damned if she didn’t make us all believers. Even my skeptical dad succumbed and started taking garlic when the first signs of a cold coming on. It really does work, for most people I know, anyway. (It seems to work best when you start taking an ample dose when the first symptoms start.) It’s also important to drink plenty of water.

My guess is that you have an allergy to garlic, or a very delicate system. My crackpot mom introduced me to the concept of “cleansing”, which means that your system is flushing out the toxins in your system too quickly, and you get cold-like symptoms. I had a doctor give me some strong vitamins once (anti-oxidents.) She warned me that if I took the full dose right away (instead of easing into the full dose), I’d get a sore throat and cold symptoms. Of course, not understanding what the doctor was talking about, I started out with the full dose. And damned if I didn’t get really sick, with the most miserable sore throat. Sounds like something like that might be happening to you. (That, or an allergy.)

3

You both do realize that colds are viral, right? And can’t be “cured” in that manner? And that all garlic might be doing is treating the symptoms?

4

Garlic could conceivably prevent colds by keeping garlic-dislikers at a safe distance, but that’s about it. It wouldn’t do the eater any good.

5

From what I can see, the answer is “maybe”. There have been claims for antiviral activity of some of the components of garlic in vitro (that is, not in the human body). I can dig up the abstract for “In vitro virucidal effects of Allium sativum (garlic) extract and compounds.”, Weber ND; Andersen DO; North JA; Murray BK; Lawson LD; Hughes BG, Planta Med, 1992 Oct, 58:5, 417-23:

“Garlic (Allium sativum) has been shown to have antiviral activity, but the compounds responsible have not been identified. Using direct pre-infection incubation assays, we
determined the in vitro virucidal effects of fresh garlic extract, its polar fraction, and the following garlic associated compounds: diallyl thiosulfinate (allicin), allyl methyl thiosulfinate, methyl allyl thiosulfinate, ajoene, alliin, deoxyalliin, diallyl disulfide, and diallyl trisulfide. Activity was determined against selected viruses including, herpes simplex virus type 1, herpes simplex virus type 2, parainfluenza virus type 3, vaccinia virus, vesicular stomatitis virus, and human rhinovirus type 2. The order for virucidal activity generally was: ajoene > allicin > allyl methyl thiosulfinate > methyl allyl thiosulfinate. Ajoene was found in oil-macerates of garlic but not in fresh garlic extracts. No activity was found for the garlic polar fraction, alliin, deoxyalliin, diallyl disulfide, or diallyl trisulfide. Fresh garlic extract, in which thiosulfinates appeared to be the active components, was virucidal to each virus tested. The predominant thiosulfinate in fresh garlic extract was allicin. Lack of reduction in yields of infectious virus indicated undetectable levels of intracellular antiviral activity for either allicin or fresh garlic extract. Furthermore, concentrations that were virucidal were also toxic to HeLa and Vero cells. Virucidal assay results were not influenced by cytotoxicity since the compounds were diluted below toxic levels prior to assaying for infectious virus. These results indicate that virucidal activity and cytotoxicity may have depended upon the viral envelope and cell membrane, respectively. However, activity against non-enveloped virus may have been due to inhibition of viral adsorption or penetration.(Abstract TRUNCATED AT 250 WORDS)”

but the article itself appears to be unavailable online except from here for US$15 (and you can buy lots more articles on garlic there).

There are a lot of unsupported claims. There is some reason to believe that garlic can be harmful in certain situations; from MEDCHEM 420: Alternative and Complementary Medicines:

“Heartburn and odor constitute the complaints for garlic consumption. Since garlic is able to diminish the ability of blood to clot (an advantage to prevent heart attacks and stroke), it might be prudent to avoid high dose garlic together with other drugs that do the same thing; examples are aspirin and coumadin. If you have a risk for hemorrhage, it would be best to not take garlic in other than culinary amounts.”