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Garlic Benefits for Fighting Heart Disease, Cancer & More
June 15, 2023
Intensely aromatic and flavorful, garlic is used in virtually every cuisine in the world. When eaten raw, it has a powerful, pungent flavor to match the truly mighty garlic benefits.
It is particularly high in certain sulfur compounds that are believed to be responsible for its scent and taste, as well as its very positive effects on human health.
Garlic benefits rank only second to turmeric benefits in the amount of research backing this superfood. At the time of this article’s publication, there are more than 7,600 peer-reviewed articles that evaluated the vegetable’s ability to prevent and improve a wide spectrum of diseases.
Do you know what all this research has revealed? Eating garlic regularly is not only good for us — it has been linked with reducing or even helping prevent four of the major causes of death worldwide, including heart disease, stroke, cancer and infections.
The National Cancer Institute does not recommend any dietary supplement for cancer prevention, but it does recognize garlic as one of several vegetables with potential anticancer properties.
Other than the most extreme, rare situations, every person on the planet should consume this vegetable. It’s extremely cost-effective, super easy to grow and tastes absolutely fantastic.
Find out more about garlic benefits, uses, research, how to grow your own and some great-tasting recipes.
What Is Garlic?
Allium sativum is a perennial plant of the amaryllis family (Amaryllidaceae), a class of bulb-shaped plants that includes chives, leeks, onions, shallots and scallions. While it’s often used as an herb or spice, garlic is botanically considered a vegetable. And unlike other vegetables, it’s more likely to added to a dish with other ingredients rather than cooked on its own.
Garlic grows underneath the soil in the form of a bulb. This bulb has long green shoots that come out from the top while its roots extend downward.
The garlic plant is native to central Asia but grows wild in Italy as well as Southern France. The bulb of the plant is what we all know as the vegetable.
What is a garlic clove? The garlic bulb is covered with several layers of inedible papery skin that when peeled away reveal up to 20 edible bulblets called cloves inside.
When it comes to the numerous types of garlic, did you know that there are over 600 names varieties of the plant? Generally speaking, there are two main subspecies: sativum (softneck) and ophioscorodon (hardneck).
The stalks of these types of plants are different, with softnecks stalks made up of leaves that remain soft, while hardnecks are rigid. Garlic scapes are produced by hardnecks and can be added to recipes for their mild, sweet and even peppery flavor.
Nutrition Facts
Garlic nutrition contains countless vital nutrients — flavonoids, oligosaccharides, amino acids, allicin and high levels of sulfur (just to name a few) — and eating this vegetable regularly has been proven to provide unbelievable health benefits.
Raw garlic also contains approximately 0.1 percent essential oil of which the main components include allyl propyl disulfide, diallyl disulfide and diallyl trisulfide.
Raw garlic is conventionally measured for cooking and medicinal purposes by the clove. Each clove is packed with health-promoting components.
A clove (approximately three grams) of raw garlic nutrition contains about:
- 4.5 calories
- 1 gram carbohydrates
- 0.2 gram protein
- 0.1 gram fiber
- 0.1 milligram manganese (3 percent DV)
- 0.9 milligram vitamin C (2 percent DV)
- 5.4 milligrams calcium (1 percent DV)
- 0.4 microgram selenium (1 percent DV)
These are just some of the top nutrients found in this vegetable. It also contains alliin and allicin, which are both health-promoting sulfur compounds. Allicin benefits are especially well-researched in studies.
Scientists are interested in the potential for these sulfur compounds derived from the vegetable to prevent and treat chronic and deadly diseases, such as cancer and cardiovascular disease, among other garlic benefits.
Benefits
As you are about to see, raw garlic benefits are plentiful. It can used as an effective form of plant-based medicine in many ways, including the following.
1. Heart Disease
According to the Centers for Disease Control and Prevention, heart disease is the No. 1 killer in the U.S., followed by cancer. This vegetable has been widely recognized as both a preventative agent and treatment of many cardiovascular and metabolic diseases, including atherosclerosis, hyperlipidemia, thrombosis, hypertension and diabetes.
A scientific review of experimental and clinical studies of garlic benefits found that, overall, consumption of this vegetable has significant cardioprotective effects in both animal and human studies.
Probably the most amazing characteristic is that it’s been shown to help reverse early heart disease by removing plaque buildup in arteries.
A 2016 randomized, double-blind study published in the Journal of Nutrition involved 55 patients, aged 40 to 75 years, who had been diagnosed with metabolic syndrome. The results of the study showed that aged garlic extract effectively reduced plaque in coronary arteries (the arteries supplying blood to the heart) for patients with metabolic syndrome.
One of the lead researchers, Matthew J. Budoff, M.D., noted:
This study is another demonstration of the benefits of this supplement in reducing the accumulation of soft plaque and preventing the formation of new plaque in the arteries, which can cause heart disease. We have completed four randomized studies, and they have led us to conclude that Aged Garlic Extract can help slow the progression of atherosclerosis and reverse the early stages of heart disease.
2. Cancer
Allium vegetables, especially garlic and onions, and their bioactive sulfur compounds are believed to have effects at each stage of cancer formation and affect many biological processes that modify cancer risk, according to a review published in Cancer Prevention Research.
In the words of the National Institutes of Health’s National Cancer Institute:
Several population studies show an association between increased intake of garlic and reduced risk of certain cancers, including cancers of the stomach, colon, esophagus, pancreas, and breast.
When it comes to how consuming this vegetable acts to prevent cancer, the National Cancer Institute explains:
… protective effects from garlic may arise from its antibacterial properties or from its ability to block the formation of cancer-causing substances, halt the activation of cancer-causing substances, enhance DNA repair, reduce cell proliferation, or induce cell death.
A French study of 345 breast cancer patients found that increased garlic, onion and fiber consumption was associated with a statistically significant reduction in breast cancer risk.
Another cancer that the vegetable has been specifically shown to positively affect is pancreatic cancer, one of the most deadly forms. The good news is that scientific research shows that increased garlic consumption may reduce the risk of developing pancreatic cancer.
A population-based study conducted in the San Francisco Bay Area found that pancreatic cancer risk was 54 percent lower in people who ate larger amounts of garlic and onions compared with those who ate lower amounts. The study also showed that increasing the overall intake of vegetables and fruits may protect against developing pancreatic cancer.
This popular vegetable also shows promise when it comes to treating cancer. Its organosulfur compounds, including DATS, DADS, ajoene and S-allylmercaptocysteine, have been found to induce cell cycle arrest when added to cancer cells during in vitro experiments.
In addition, these sulfur compounds have been found to induce apoptosis (programmed cell death) when added to various cancer cell lines grown in culture. Taking liquid garlic extract and S-allylcysteine (SAC) orally has also been reported to increase cancer cell death in animal models of oral cancer.
Overall, this vegetable clearly show some real potential as a cancer-fighting food that should not be ignored or discounted.
3. High Blood Pressure
An interesting phenomenon is that this common herb has been shown to help control high blood pressure. One study looked at the effect of aged garlic extract as an adjunct treatment for people already taking antihypertensive medication yet still having uncontrolled hypertension.
The study, published in the scientific journal Maturitas, evaluated 50 people with “uncontrollable” blood pressure. It was uncovered that simply taking four capsules of aged garlic extract (960 milligrams) daily for three months caused blood pressure to drop by an average of 10 points.
Another study published in 2014 found that the vegetable has “the potential to lower BP in hypertensive individuals similarly to standard BP medication.”
This study further explains that the vegetable’s polysulfides promote the opening or widening of blood vessels and, hence, blood pressure reduction.
4. Colds and Infections
Experiments have shown that garlic (or specific chemical compounds like allicin found in the vegetable) is highly effective at killing countless microorganisms responsible for some of the most common and rarest infections, including the common cold. It actually might help prevent colds as well as other infections.
In one study, people took either garlic supplements or a placebo for 12 weeks during cold season (between November and February). Those who supplemented with the vegetable were less likely to get a cold, and if they did get a cold, they recovered faster than the placebo group.
The placebo group had a much greater likelihood of contracting more than one cold over the 12-week treatment period as well.
The study attributes the vegetable’s ability to prevent the common cold to its star biologically active component component, allicin. Its antimicrobial, antiviral and antifungal properties can help relieve the common cold as well as other infections.
Allicin in particular is believed to play an important role in this vegetable’s antimicrobial powers.
5. Male and Female Hair Loss (Alopecia)
AÂ clinical trial was conducted to test what a survey has shown to be a growing practice in Turkey: using garlic to treat baldness. Mazandaran University of Medical Sciences researchers from Iran tested how garlic gel applied on the scalp twice a day for three months could affect people taking corticosteroids for alopecia.
Alopecia is a common autoimmune skin disease, causing hair loss on the scalp, face and sometimes on other areas of the body. Different treatments are currently available, but no cure is yet known.
The researchers discovered that the use of the gel significantly added to the therapeutic efficacy of topical corticosteroid in the treatment of alopecia areata. Although the study didn’t test it directly, applying garlic-infused coconut oil as a standalone treatment might even be more beneficial as a hair loss remedy because it mitigates the risk of absorbing harmful corticosteroids in the skin.
6. Alzheimer’s Disease and Dementia
Alzheimer’s disease is a form of dementia that can rob people of the ability to think clearly, perform everyday tasks and, ultimately, remember who they even are. This vegetable contains antioxidants that can support the body’s protective mechanisms against oxidative damage that can contribute to these cognitive illnesses.
When it comes to Alzheimer’s patients, β-amyloid peptide plaques are commonly observed in the central nervous system, and these plaque deposits result in the production of reactive oxygen species and neuronal (cells in the nervous system) damage.
A study published in the Journal of Neurochemistry found “significant neuroprotective and neurorescue properties” of aged garlic extract and its active compound SAC. The researchers conclude from their findings that the aged extract along with SAC can be used to develop future drugs to treat Alzheimer’s disease.
7. Diabetes
Eating this popular vegetable has been shown to help regulate blood sugar levels, potentially stop or decrease the effects of some diabetes complications, as well as fight infections, reduce LDL cholesterol and encourage circulation.
A study of diabetic rats showed that this vegetable may be very helpful at improving the overall health of diabetics, including the mitigation of common diabetic complications like atherosclerosis and nephropathy. These rats, which received a daily extract of raw garlic for seven weeks, had significantly lower serum glucose (blood sugar level), cholesterol and triglyceride levels.
Compared to the control group, the rats receiving raw garlic had 57 percent less serum glucose, 40 percent lower serum cholesterol levels and 35 percent lower triglycerides. In addition, urinary protein levels in garlic-treated rats were 50 percent lower.
Another study also showed that for type II diabetes patients, garlic significantly improved blood cholesterol levels. Specifically, its consumption reduced total cholesterol and LDL (bad) cholesterol and moderately raised HDL cholesterol compared to placebo.
8. Remedy Skin Issues
Garlic has many potential benefits for the skin. Laboratory findings showed it may act in much the same way as some current conventional treatments for keloids, making it a promising possible remedy.
To use, crush a few garlic cloves (ideally with a garlic press) and apply them directly to the skin. Rinse after 15 minutes or if you start to notice irritation.
How to Use
Garlic is best used raw for microbial properties, although cooked garlic still has a lot of value. In fact, the antioxidant value is equal (or sometimes even higher) when cooked, which is counterintuitive because for most foods cooking tends to decrease nutritional content.
Even black garlic, which is used in Asian cuisines and occurs when it is heated over a course of several weeks, has proven to be beneficial for our health.
For Skin and Infections
Another way to use garlic is for infections. Using the oils of the garlic plant is an excellent natural remedy for many types of infections, including ear and skin infections as well as sore throats.
Traditional cultures that don’t typically struggle with these types of diseases receive regular intake of this in their diets.
For Weight Loss
This herb helps boost your metabolism, which can support weight loss. Adding raw or cooked garlic to healthy and well-balanced meals every day can promote weight loss.
In addition to this plant benefit, it may help sexually, too. Because allicin promotes blood flow to reproductive organs and stimulates circulation, you may find that adding this vegetable to your diet improves your sexual health.
Recipes
If you want to harness the healing power of this vegetable, try adding it to some of your favorite recipes. The possibilities with this kitchen staple are truly endless.
You can add raw garlic to recipes that are sautéed, roasted or baked. You can also toss some raw garlic into your next homemade salad dressing, marinade, tomato sauce, soup or stew.
Adding the raw garlic to any vegetable, fish or meat dish is sure to intensify the flavor and offer health benefits. Of course, cooked garlic benefits are also impressive and offer a more mild flavor when added to meals, like garlic aioli (sautéed garlic with olive oil).
Roasting garlic is also an easy option when cooking garlic. Simply chop off the top head so the cloves are exposed. Then drizzle it with olive oil and wrap it with foil.
To roast garlic, leave it in a 400 degree oven for about 30 minutes, until the cloves become brown and tender.
Ultimately, whether you’re using clove of garlic raw or cooked, you can increase the benefits of garlic by chopping or crushing it and letting it sit before eating.
Chopped or minced garlic activates alliinase enzymes in the vegetable’s cells, and sitting allows these enzymes to convert some of the clove’s allin into allicin. Allicin then rapidly breaks down to form a variety of organosulfur compounds.
Scientists suggest allowing garlic to stand for 10 minutes after chopping or crushing before cooking it.
To mince garlic, peel away the skin, separate the cloves and crush them with the flat side of a large knife. First give the crushed clove a rough chop, and then go over it again with a rocking motion, using one hand to hold the knife handle and the other to rock the knife from the top.
A garlic press can also be used to crush the cloves.
Here are a few of my favorite garlic recipes to try so you can experience the many health benefits of garlic nutrition:
In addition to these healthy recipes, some popular ways to use garlic in food include:
- garlic breadsticks (best with a sprouted and fresh-baked load of bread)
- garlic with olive oil on gluten-free or whole wheat pasta
- garlic mashed potatoes
- garlic butter that can be added to bread or veggies for extra flavor and benefit
How to Grow at Home
Garlic is one of the more simple crops to grow. It thrives in different zones all across the U.S.
For those of us in the Northern Hemisphere, we should plant our cloves during the fall season and harvest them in late spring/early summer.
Don’t throw away any leftover cloves from your curry dish or garlic recipe. Clove food scraps are amazingly simple to use to regrow garlic plants.
To plant garlic, put the cloves root end down in a sunny spot in your garden, and trim off the shoots once the bulb produces them. This vegetable flourishes in dry, loose, well-drained soils in sunny locations.
When to harvest garlic requires good judgment, but in general, when you notice that the lower leaves are turning grown, you can dig up a few bulbs and check if they’re ready to eat. (It’s even useful to save the garlic peels.)
Each bulb is made up of four to 20 cloves with each clove weighing about a gram. Garlic supplements can be made from fresh, dried or aged garlic — or garlic oil.
Black garlic is a type of caramelized garlic, which was first used as a food ingredient in Asian cooking. To create black garlic, heads are heated over the course of several weeks.
This heating process makes the garlic black in color. It also makes it sweet and syrupy. The black variety is now available for purchase in the U.S..
Risks and Side Effects
Can eating raw garlic be harmful? When taken by mouth, raw garlic can cause:
- burning a sensation in the mouth or stomach
- bad breath
- heartburn
- gas
- bloating
- nausea
- vomiting
- body odor
- diarrhea
The likelihood of these side effects increases with an increase in the amount consumed.
In general, garlic in any form can increase bleeding risk because it acts as a natural blood thinner. Speak to your doctor before consuming raw garlic if you take blood thinners. Due to bleeding concerns, stop taking the vegetable at least two weeks before any scheduled surgery.
During pregnancy and breastfeeding, this vegetable is believed to be safe in food amounts but might be unsafe in medicinal amounts.
When taken by mouth in appropriate, small amounts for short periods of time, it is said to be safe for children. However, it should never be given to children in large doses.
If you have any gastrointestinal problems, it’s important to know that raw garlic can irritate the GI tract. People with ulcers should most likely avoid this vegetable raw.
To avoid intensified GI issues, don’t eat raw garlic on an empty stomach. It can cause severe, burn-like skin irritation if applied to the skin alone directly so be cautious with skin contact.
Talk to your doctor before consuming raw garlic if you have low blood pressure, ulcers or other GI issues, thyroid problems, or any other ongoing health concerns.
Also speak with your doctor before consuming medicinally if you are taking any medications, especially the following:
- Blood-thinning medications
- Isoniazid (Nydrazid)
- Birth control pills
- Cyclosporine
- Medications for HIV/AIDS
- Nonsteroidal anti-inflammatory drugs
These are the best ways to guard against any possible negative side effects:
- Consume it in culinary doses
- Eat traditional recipes
- Avoid taking raw garlic in massive amounts
Final Thoughts
- Some of the most profound benefits of raw garlic proven by science include helping reverse heart disease in its early stages, prevent and fight various forms of cancer, improve the health of diabetics, and even showing promise for serious cognitive diseases like Alzheimer’s.
- To make the most of its active compounds, it’s best to either consume it raw or to crush/cut it and leave it out for a bit (10 minutes) before you add it to your cooked recipes.
- A clove with a meal each day is a great, easy way to start reaping benefits on a consistent basis. Remember to consume the raw version with food rather than on an empty stomach to prevent gastrointestinal problems as well as bad breath.
- If you find it hard to get rid of your garlic breath, just try eating some raw parsley afterward.