4 major health benefits of garlic, from boosting your immune system to lowering cholesterol

• Garlic benefits include improving heart health and reducing the risk of certain cancers.
• One garlic clove also contains important vitamins and minerals like vitamin C, iron, and manganese.
• To get health benefits from garlic, opt for whole cloves rather than pre-minced versions in jars.

Garlic is an easy way to amp up the flavor to many meals. And beyond its widespread use for taste and seasoning, garlic is also packed with key nutrients that may benefit your health.

Here are four benefits of garlic and how much you should add to your diet.

Garlic nutrition

One raw clove of garlic has roughly 14 calories, 0.57 grams of protein, and about three grams of carbohydrates (one slice of white bread has 34 grams of carbohydrates, for comparison.)

Though one raw clove of garlic is pretty small, there is actually a significant amount of the following vitamins and nutrients:

• Vitamin C (2.81 mg)
• Selenium (1.28 mcg)
• Manganese (0.15 mg)
• Iron (0.15 mg)

One garlic clove packs a dense nutrient profile, but garlic's small size means we're not getting a large amount of nutrients from a single garlic clove. "The concentration is not as robust as we would think about, say eating a full salad," says Tom Holland, MD, a physician scientist at Rush University Medical Center.

You shouldn't add too much garlic to your diet, too quickly. "One to two cloves a day should be the maximum consumed by anyone," says Tracey Brigman, a food and nutrition expert at the University of Georgia. Eating more than that may cause upset stomach, diarrhea, bloating, or bad breath.

"If you opt for adding two cloves of garlic a day to your diet, you may also want to add fresh parsley, mint, or raw apples to your diet to help prevent the bad breath associated with garlic consumption," Brigman says.

1. Boost immunity

The flavorful bulbs at the end of the garlic plant are also rich with nutritious compounds called allicin and alliinase. In fact, the presence of allicin helps garlic boost the immune system.

A 2015 review found that garlic fortifies the immune system by stimulating immune cells like macrophages, lymphocytes, and natural killer cells. Garlic may also help stave off colds and flu because of the plant's antimicrobial and antibiotic properties, Brigman says, which would stop the growth of viruses, bacteria, and other unwanted organisms.

However, Brigman notes that although some studies show a benefit, there is a lack of strong evidence that garlic supplements help prevent or reduce severity of the common cold and flu.

You should still wash your hands, avoid touching your face, stay hydrated, and practice other methods to prevent getting sick. Garlic probably won't prevent sickness, but it may provide a little extra boost if you want to strengthen your immune system.

2. Reduce cancer risk

"[Garlic is] also a good source of phytochemicals, which help to provide protection from cell damage, lowering your risk for certain cancers," says Brigman.

Phytochemicals are compounds in vegetables and fruits associated with a reduced risk of chronic illness. There is some evidence that consuming phytochemicals through garlic can have anticarcinogenic effects and potentially lower risk for stomach and colorectal cancers.

However, research in human subjects is lacking, and it's not proven that garlic consumption can actually prevent or treat cancer.

3. Improve heart health

A 2019 study found that consuming two capsules of garlic extract a day for two months can lower blood pressure and decrease arterial stiffness for people with hypertension.

"Garlic seems to lead to overall protection for your heart," Brigman says.

In addition, a 2013 report suggested that garlic can reduce lipids in the blood, which means lower cholesterol and thus a lower risk for plaque build up in the cardiovascular system.

The amount of garlic needed to achieve these heart healthy effects differ among individuals. However, looking at the research available on the subject, it's best to consume about four fresh cloves of garlic per week, says Puja Agarwal, PhD, a nutrition epidemiologist at Rush University Medical Center.

4. Enhance workouts

Historically, Ancient Greek athletes ate garlic before an event to improve their performance. That's because garlic releases nitric oxide, a compound that relaxes blood vessels and lowers blood pressure. This compound is often released while running to supply more oxygen to working muscles.

Some animal studies in rats and mice have also found that garlic can improve athletic endurance, finds a 2007 review. However, Brigman notes the inconclusive data in human subjects means we can't draw definitive conclusions.

Insider's takeaway

Brigman says to opt for whole garlic rather than the pre-minced version in jars, as you will get the most health and medicine benefits from raw garlic.

This is because the alicin in garlic, which contributes to many of its health benefits, is most potent briefly after it has been chopped, crushed, or chewed. In fact, the amount of allicin in garlic cloves peaks 10 minutes after chopping and is destroyed by temperatures over 140 degrees Fahrenheit.

"If you want to add garlic to hot meals, then add it when your food is almost finished cooking to limit the destruction of allicin," Brigman says.

Allicin can also be consumed in supplemental forms, such as in pills, but the most benefit comes from raw garlic, Brigman says. This may be due to the fact that garlic supplements do not have regulated manufacturing standards and may actually contain little to no allicin.

6 health benefits of turmeric and how to add it to your diet5 science-backed benefits of eating spicy food and how it can help you burn calories and live longer7 health benefits of watermelon that prove it's the perfect summer snack5 science-backed benefits of vitamin B12 and how to get enough of it