Garlic

People often say that garlic has medicinal properties. Some claim it lowers blood pressure, others swear it helps cholesterol and reduces clotting, and some even think it protects against cancer. I’ve also heard that garlic is “healthier” 10-15 minutes after it has been crushed or minced. Is any of this true?

The Science of Single Foods

As someone who regularly reads the scientific literature on the health benefits of food I can assure you that this is not an easy question to answer. The problem is that the effect of any single food on human health is likely to be small at best, and small effects are very difficult to detect with reliability. Studies must be incredibly well-designed to contribute anything of value to our understanding of how a food works in the human body. Also, many studies must be taken together in context for the data to be evaluated properly.

I have been researching this garlic question on and off for months and feel only slightly more confident today than I did when I started. To summarize, there are a good number of studies addressing the health value of garlic, but very very few of them are well-designed and published in reputable journals. The problem with having a large number of poor-quality studies is that results are often conflicting and difficult to interpret. Thus, when another scientist comes in to do a meta-analysis (pooling data from many studies and re-analyzing it for stronger statistics) the findings are usually inconclusive.

However, inconclusive findings do not enable me (or anyone) to say there is no benefit. What I can say is that more research is needed and if there is a benefit it is likely to be small. (How unsatisfying is that?!). But personally I would still recommend eating garlic for health. Why?

Small Benefits Are Important

Although we cannot say exactly why garlic is good for you, it is almost certainly not bad for you. Moreover, although it is difficult to attribute a particular health benefit to a single food, we do know that people who eat the most vegetables tend to be healthier than people who fewer.

Many nutrition scientists are beginning to suspect that the benefit of foods like garlic are primarily relevant in the context of a whole diet and cannot be evaluated independently. This means that it is less important that the individual studies I mentioned earlier are inconclusive, because they are likely not sensitive enough to evaluate the complex interactions of whole foods and food combinations on human physiology.

The Best Reason To Eat Garlic

The most important thing you can do for your health is eat a diverse diet of natural, unprocessed foods. Garlic is an amazing ingredient that imparts a unique and wonderful taste to the food it is cooked with. If you like garlic and it encourages you to eat your vegetables, then it’s good for you.

If it makes you feel slightly better knowing that it may help your heart or reduce inflammation, that’s awesome but less important.

What About The Crush?

If you do hope garlic can add to your health, is there any benefit in crushing it early? Probably.

Scientists have long suspected that the active ingredient in garlic is a substance called allicin. A recent study from Queen’s University showed that it is actually a decomposition product of allicin that has the most potent antioxidant activity.

Interestingly, allicin is created from an enzyme called alliinase that is not released from plant cells until they are damaged. Alliinase is what gives garlic (and onions) their strong odor and is thought to be a self-defense mechanism for these plants. When garlic is crushed, alliinase becomes active and begins creating allicin. As allicin is created and breaks down, the antioxidant potential of garlic is dramatically increased. Optimal antioxidant levels are created about 10 minutes after garlic is crushed.

It has not yet been shown that this increased antioxidant activity is a benefit to humans, but the principle is compelling enough to try to remember to crush your garlic a little early. If you are anything like me though, this feat is almost impossible. Apparently garlic hasn’t done that much for my memory.

What are your favorite reasons to eat garlic?

Originally published March 27, 2009.

It came as a bit of a shock for me to learn that some people hate peeling garlic so much they have completely given up using it.

Sure the flavor is strong, but almost all cooks consider garlic indispensable. If peeling it is your problem, don’t fret! This one little trick makes garlic a cinch to peel.

First, remove single cloves from a very fresh garlic bulb (garlic is cheap, you should buy it every week). I rarely use more than one or two when cooking for two people.

Next, place the garlic clove on a cutting board oriented so that its curve is pointed upward, or at least sideways. There may be space beneath the clove, which is good. Grab a wide blade knife, such as a chef’s knife or santoku knife. Rest the flat end of the blade on the top of the garlic (as shown) and hit the top with the palm of your hand once or twice, quickly and firmly.

The impact will slightly crush the garlic clove while the outer skin retains its shape and becomes dislodged. Examine the clove and remove as much of the skin as you can (usually all of it). If some skin remains stuck to the clove hit it a few more times, using a bit more force. It does not matter if you damage the garlic.

Use the knife to cut off the hard end that attached the clove to the bulb. This may help to remove any remaining skin as well. If you still have some skin stuck to the clove, it should be easy to pick off at this point. If not, smash it a couple more times.

Recipes often called for minced garlic, so after I peel my clove I often crush it completely then make thin slices along the length, then width. Scrape off any pieces of garlic sticking to the side of the knife then quickly mince the remaining chunks. This entire process takes less than 1 minute.

It is a great idea to prepare your garlic at least 10-15 minutes before you plan to cook with it, something that makes it substantially healthier.

I can’t imagine this being any easier, but I am always happy to hear your suggestions and comments!