Cancer cells are a little like vampires: they don’t like garlic. A member of the lily family, garlic is sometimes called ‘the stinking rose’ and its power seems to have been recognized from ancient times: Garlic’s use in China dates back to 2,000 BCE; Egyptian pyramid workers went on strike when garlic was withheld from their daily rations; and while Romans did not really care for its flavor, they felt it conveyed strength and made soldiers fierce. Some might say it was just their breath that was strong since they chewed large amounts of fresh garlic, but it was more likely the potent health-promoting phytonutrients in garlic that made the Roman army so fierce.
Not surprisingly, many of these phytonutrients also help to fight cancer. While garlic contains a multitude of healthful substances, this article focuses on garlic’s abundant sulfur-containing phytonutrients. These compounds promote specific anti-cancer processes within the liver including carcinogen metabolism, antioxidant activity, and anti-inflammation.
How Your Liver Works
An important function of the liver is removing harmful substances–particularly toxins and carcinogens–from your body. The liver works by filtering out toxins from the blood using enzymes in two phases: phase 1 converts the toxin into an intermediate metabolite; phase 2 then processes these metabolites into a form that can be excreted from the body. Sometimes, the phase 1 process creates substances that are more damaging than the toxin itself, and unless there are enough phase 2 enzymes to neutralize them, these substances can damage cells and set the stage for cancer promotion. Unfortunately, many things we eat, drink and breath can activate an overabundance of phase 1 enzymes, so an imbalance between phases is not uncommon.
Garlic to the Rescue!
Garlic contains two sulfur compounds that support a healthy balance between phase 1 and phase 2 detoxification. The first, diallyl sulfide (DAS) impacts phase 1 enzymes by slowing down their production of DNA-damaging carcinogenic compounds. The second—diallyl trisulfide (DAT)—provides further protection by increasing the production of phase 2 enzymes, which means potential carcinogens can be deactivated and eliminated at a faster rate. But that’s not all DAT and its fellow allyl sulfides do. Besides increasing the production of phase 2 enzymes, DAT stimulates antioxidant activity within cells. There is also some evidence that other garlic-derived sulfur compounds stimulate the production of glutathione, a powerful intracellular antioxidant. In addition, several sulfur compounds in garlic have been shown to keep inflammation—a cancer promoter—in check.
Tips for Cooking with Garlic
- Crushing or chopping garlic activates an enzyme that catalyzes the formation of thiosulfinates. One of these thiosulfinates—allicin—is the substance from which most of the compounds responsible for garlic’s anti-cancer activity are derived.
- However, it takes a few minutes for these thiosulfinates to form. So let garlic stand at least 10 minutes after crushing or chopping prior to cooking.
- Research has shown that microwaving or boiling garlic in uncrushed, whole clove form for as little as 60 seconds will deactivate its enzymes and prevent them from working. So if you are looking to reap garlic’s health benefits, then be sure to heed the first two tips above before cooking.
Mediterranean Shrimp and Asparagus Salad and Dressing
This recipe has been adapted from one on the World’s Healthiest Food website. Note that a key ingredient below includes another member of the lily family—asparagus—that’s loaded with phytonutrients and that we wrote about last spring.
- 4 medium cloves garlic, pressed
- 1 pound medium-sized cooked shrimp, best bought still frozen
- 1 bunch( approximately 1 lb) asparagus, cut into 1 inch pieces, discarding bottom fourth
- 3 tablespoons vegetable broth
- 1 fresh tomato, diced into 1/2-inch pieces
- 3 tablespoons chopped fresh parsley (or 3 teaspoons dried parsley if fresh is not available)
- 1 small head of romaine lettuce, chopped
- 2 ounces crumbled goat cheese (may substitute with feta if desired)
- Salt and fresh cracked black pepper to taste
- 3 tablespoons fresh lemon juice
- 2 tablespoons extra virgin olive oil (preferably unfiltered)
- 1 tablespoon Dijon mustard
- 1 teaspoon honey
- Salt and cracked pepper to taste
- Press garlic and let sit for 10 minutes to bring out its hidden benefits.
- Make sure shrimp is completely thawed and patted dry with a paper towel, or it will dilute the flavor of the salad.
- Add broth to medium skillet and after it has heated up, saute asparagus for 5 minutes.
- Whisk together lemon, oil, mustard, honey, garlic, salt and pepper. Toss shrimp, asparagus, parsley, and tomato with dressing and herbs. Allow shrimp salad to marinate for at least 15 minutes.
- Discard outer leaves of lettuce head, rinse, dry, and chop. Serve shrimp mixture on bed of lettuce and top with crumbled cheese.