Foods/Supplements-Vitamins: Garlic

Over the years, I have become increasingly bemused by the vituperation that the humble garlic press can provoke:

"For instance, chef Anthony Bourdain calls garlic presses "abominations" and advises "don't put it through a press. I don't know what that junk is that squeezes out of the end of those things, but it ain't garlic." The British cookery writer Elizabeth David once wrote an essay titled "Garlic Presses are Utterly Useless"." [1]

(Granted, there are certain dishes where sliced or chopped garlic is more practical, but the complaints often revolve around flavor.)

Most of the phytochemicals that are potentially useful in PCa, also have a protective role in the source plant. It is not uncommon for the chemical to be compartmentized in an inactive form, with the liberating enzyme held elsewhere in the cell. Damage of the cell is required to bring them together to activate the chemical.

Garlic (Allium sativum) sulfur compounds that have been widely studied are diallyl disulfide (DADS) & diallyl trisulfide (DATS). More recently: S-allylcysteine (SAC). The enzyme that frees them is alliinase. Garlic contains the compound alliin, & alliinase converts alliin into allicin, which is unstable & quickly forms DADS, etc.

Alliinase is destroyed by heat - as in cooking. No garlic is harmed when prepping for a '40 clove chicken' recipe, which is presumably why the garlic-averse are able to eat it.

An efficient way of producing DADS & DATS is to put the cloves through a garlic press. Let the crushed garlic stand for 10 minutes so that the enzyme has a chance to do its job. Adding the mush to a hot pan prematurely will halt the activation.

Cooking will also alter the active phytochemicals. The 'raw' flavor of uncooked crushed garlic in salad dressings, falafel, etc, becomes progressively muted in cooked dishes, depending on cooking time.

Perhaps the most respected garlic supplement is Kyolic aged garlic extract. Kyolic has a perplexing number of garlic products (I counted 25), including "vegetarian" (vegetarian garlic! - no gelatin in the capsule. True vegans must find the supplement field very limited) & there is even a prostate product (Prosta-Logic), which might have some use - if one has no cancer.

The Kyolic site is a bit vague as to active constituents:

"... the truly odorless Kyolic Aged Garlic Extract that contains safe, stable, bioavailable and beneficial compounds." [2]

[3] DADS & PCa. 15 PubMed cell study hits - here are 4:

[3a] (2012 - Canada)

"Our results showed that DADS markedly inhibited the growth of the DU145 cells by induction of apoptosis."

[3b] (2012 - India)

"The results suggests that DADS decreases the survival rate of androgen independent prostate cancer cells by modulating the expression of IGF {insulin-like growth factor} system ..."

[3c] (2010 - Korea)

"the activities of matrix metalloproteinase (MMP)-2 and -9 in LNCaP cells were dose-dependently inhibited by treatment with DADS ..." "... MMPs are critical targets of DADS-induced anti-invasiveness in human prostate cancer LNCaP cells."

[3d] (2009 - U.S.)

"This study shows clearly that DADS causes caspase-dependent apoptosis in human cancer cells through a Bax-triggered mitochondrial pathway."

[4] DATS & PCa. 22 PubMed cell study hits - here are 4:

[4a] (2012 - China)

"The effects of five derivatives of diallyl trisulfide (DATS) were investigated on apoptosis in prostate cancer PC-3 cells, including dibutenyl trisulfide (DBTS), bis(2-methylallyl) trisulfide (2-M-DATS), dipentenyl trisulfide (DPTS), bis(3-methylbut-2-enyl) trisulfide (3-M-DBTS), and dihexenyl trisulfide (DHTS)."

Might these be present in a dish after cooking?

"All of the evidences above indicate that DATS derivatives suppressed proliferation of PC-3 cells which was associated with the induction of apoptosis regulated by Bax/Bcl-2."

[4b] (2009 - U.S.)

"Transcriptional repression and inhibition of nuclear translocation of androgen receptor by diallyl trisulfide in human prostate cancer cells."

"The present study was undertaken to determine the effect of diallyl trisulfide (DATS), a promising cancer chemopreventive constituent of garlic, on androgen receptor (AR) protein expression and function using prostate cancer cells."

"The present study shows, for the first time, that DATS treatment suppresses AR function in prostate cancer cells."

[4c] (2007 - U.S.)

"... the present study reveals that the mitochondria-mediated cell death by DATS is associated with ROS {reactive oxygen species} generation ..."

[4d] (2005 - U.S.)

"Diallyl trisulfide-induced G(2)-M phase cell cycle arrest in human prostate cancer cells is caused by reactive oxygen species-dependent destruction and hyperphosphorylation of Cdc 25 C."

[5] S-allylcysteine & PCa. Just 5 PubMed hits - here are 2:

[5a] (2012 - China)

"S-allylcysteine induces cell cycle arrest and apoptosis in androgen-independent human prostate cancer cells."

[5b] (2007 - Hong Kong) Finally, a mouse study!

"To evaluate the effect of S-allylcysteine (SAC) on CWR22R, a human androgen-independent (AI) prostate cancer xenograft, in nude mice."

"Treatment with SAC resulted in inhibition of the growth of CWR22R, with no detectable toxic effect on nude mice."














7 Replies

  • I always enjoy your posts. So, does this mean we should eat raw crushed garlic? I remember seeing a programme once that proved that eating raw garlic helped with ED. I think they said 6 cloves a day. Of course, I think your partner would have to eat 6 cloves of raw garlic too! We have broken more garlic crushers than I can count on one hand so now chop to varying degrees for various dishes, or use a pestle and mortar with a pinch of salt to crush.

  • There are various ways of eating raw crushed garlic without being particularly aware of it. This gets around the partner issue. Home made salad dressings (store-bought always have at least one objectionable ingredient). Salsas. Falafel.

    Some cooked dishes are prepared so quickly, that the garlic still has some bite. The important thing is to give the enzyme time to work before adding to the pan.


  • So I conclude?

  • Well,

    The Kyolic supplement probably has benefit.

    Raw crushed garlic isn't for everyone, but does cooked garlic have any potency? I like to think that the metabolites of DADS & DATS have benefit. But we are never going to see a PCa clinical trial.

    When I make a stew that is going to cook a while, I'll add crushed garlic from a whole bulb. The flavor is mild by the time the stew is cooked. I figure there must be some residual therapeutic benefit.

    Outside of cancer, garlic studies show that:

    "garlic reduces cholesterol, inhibits platelet aggregation, reduces blood pressure, and increases antioxidant status. Since 1993, 44% of clinical trials have indicated a reduction in total cholesterol, and the most profound effect has been observed in garlic's ability to reduce the ability of platelets to aggregate. Mixed results have been obtained in the area of blood pressure and oxidative-stress reduction."


  • Are there any double-blinded RCTs in this listed (or elsewhere) demonstrating survival benefit from garlic extracts for patients diagnosed with PCa?

  • Richard,

    You already know the answer - who would fund such a trial?

    & the same goes for any of the food items in my series of posts.

    Many men adjust their diet after a PCa diagnosis. Did you?


  • As to Garlic, there is God's approach. To simply get the benefits of the many sulfur compounds that exist in abundance in the bulb. I may cook with it for flavor--which I do often, but for Phytosterol/ Polyphenolic/sulfur benefits of Garlic, to use it as a treatment or drug, I take chopped fresh garlic and take two heaping teaspoons. There are so many positive Natural Healing studies on Garlic---that there is no need to argue about its benefits--just take it naturally as God made it, for full benefit.