It is closely related to onions, shallots and leeks. Each segment of a garlic bulb is called a clove. There are about 10–20 cloves in a single bulb, give or take.

Garlic grows in many parts of the world and is a popular ingredient in cooking due to its strong smell and delicious taste.

However, throughout ancient history, the main use of garlic was for its health and medicinal properties.

Its use was well documented by many major civilizations, including the Egyptians, Babylonians, Greeks, Romans and Chinese.

Scientists now know that most of its health benefits are caused by sulfur compounds formed when a garlic clove is chopped, crushed or chewed.

Perhaps the most famous of those is known as allicin. However, allicin is an unstable compound that is only briefly present in fresh garlic after it’s been cut or crushed.

Other compounds that may play a role in garlic’s health benefits include diallyl disulfide and s-allyl cysteine.

The sulfur compounds from garlic enter the body from the digestive tract and travel all over the body, where it exerts its potent biological effects. Garlic is a plant in the onion family that’s grown for its distinctive taste and health benefits. It contains sulfur compounds, which are believed to bring some of the health benefits.

Calorie for calorie, garlic is incredibly nutritious.

One clove (3 grams) of raw garlic contains:

• Manganese: 2% of the Daily Value (DV)
• Vitamin B6: 2% of the DV
• Vitamin C: 1% of the DV
• Selenium: 1% of the DV
• Fiber: 0.06 grams
• Decent amounts of calcium, copper, potassium, phosphorus, iron and vitamin B1

This comes with 4.5 calories, 0.2 grams of protein and 1 gram of carbs.

Garlic also contains trace amounts of various other nutrients. In fact, it contains a little bit of almost everything you need. Garlic is low in calories and rich in vitamin C, vitamin B6 and manganese. It also contains trace amounts of various other nutrients.

Garlic supplements are known to boost the function of the immune system.

One large, 12-week study found that a daily garlic supplement reduced the number of colds by 63% compared to a placebo.

The average length of cold symptoms was also reduced by 70%, from 5 days in the placebo group to just 1.5 days in the garlic group.

Another study found that a high dose of aged garlic extract (2.56 grams per day) reduced the number of days sick with cold or flu by 61%.

However, one review concluded that the evidence is insufficient and more research is needed.

Despite the lack of strong evidence, adding garlic to your diet may be worth trying if you often get colds.

One medium onion has just 44 calories but delivers a considerable dose of vitamins, minerals and fiber.

This vegetable is particularly high in vitamin C, a nutrient involved in regulating immune health, collagen production, tissue repair and iron absorption.

Vitamin C also acts as a powerful antioxidant in your body, protecting your cells against damage caused by unstable molecules called free radicals.

Onions are also rich in B vitamins, including folate (B9) and pyridoxine (B6) — which play key roles in metabolism, red blood cell production and nerve function.

Lastly, they’re a good source of potassium, a mineral in which many people are lacking.

In fact, the average potassium intake of Americans is just over half the recommended daily value (DV) of 4,700 mg.

Normal cellular function, fluid balance, nerve transmission, kidney function and muscle contraction all require potassium.

Onions are low in calories yet high in nutrients, including vitamin C, B vitamins and potassium.

Their potent anti-inflammatory properties may also help reduce high blood pressure and protect against blood clots.

Quercetin is a flavonoid antioxidant that’s highly concentrated in onions. Since it’s a potent anti-inflammatory, it may help decrease heart disease risk factors, such as high blood pressure.

A study in 70 overweight people with high blood pressure found that a dose of 162 mg per day of quercetin-rich onion extract significantly reduced systolic blood pressure by 3–6 mmHg compared to a placebo.

Onions have also been shown to decrease cholesterol levels.

A study in 54 women with polycystic ovarian syndrome (PCOS) found that consuming large amounts of raw red onions (40–50 grams/day if overweight and 50–60 grams/day if obese) for eight weeks reduced total and “bad” LDL cholesterol compared to a control group.

Additionally, evidence from animal studies supports that onion consumption may reduce risk factors for heart disease, including inflammation, high triglyceride levels and blood clot formation.

Onions are an excellent source of antioxidants. In fact, they contain over 25 different varieties of flavonoid antioxidants.

Red onions, in particular, contain anthocyanins — special plant pigments in the flavonoid family that give red onions their deep color.

Multiple population studies have found that people who consume more foods rich in anthocyanins have a reduced risk of heart disease.

For example, a study in 43,880 men showed that habitual intakes as high as 613 mg per day of anthocyanins were correlated to a 14% lower risk of nonfatal heart attacks.

Similarly, a study in 93,600 women observed that those with the highest intake of anthocyanin-rich foods were 32% less likely to experience a heart attack than women with the lowest intake.

Additionally, anthocyanins have been found to protect against certain types of cancer and diabetes.

Many laboratory studies suggest that piperine — the main active compound in black pepper — may effectively fight inflammation.

For example, in studies in rats with arthritis, treatment with piperine resulted in less joint swelling and fewer blood markers of inflammation.

In mouse studies, piperine suppressed inflammation in the airways caused by asthma and seasonal allergies.

However, the anti-inflammatory effects of black pepper and piperine have not yet been studied extensively in people.

In particular, it has demonstrated potential benefits for symptoms related to degenerative brain conditions like Alzheimer’s and Parkinson’s disease.

For example, a study in rats with Alzheimer’s disease found that piperine improved memory, as the distribution of piperine enabled the rats to repeatedly run a maze more efficiently than rats not given the compound.

In another rodent study, piperine extract seemed to decrease the formation of amyloid plaques, which are dense clumps of damaging protein fragments in the brain that have been linked to Alzheimer’s disease.

Yet, studies in humans are needed to confirm whether these effects are also seen outside animal studies.

In one study, rats fed a black pepper extract had a smaller spike in blood sugar levels after consuming glucose compared to rats in the control group.

Additionally, 86 overweight people taking a supplement containing piperine and other compounds for 8 weeks experienced significant improvements in insulin sensitivity — a measure of how well the hormone insulin removes glucose from the bloodstream.

However, it’s unclear whether the same effects would occur with black pepper alone, as a combination of many active plant compounds was used in this study.

A 1/2 cup (30 grams) of fresh, chopped parsley provides:

• Calories: 11 calories
• Carbs: 2 grams
• Protein: 1 gram
• Fat: less than 1 gram
• Fiber: 1 gram
• Vitamin A: 108% of the Reference Daily Intake (RDI)
• Vitamin C: 53% of the RDI
• Vitamin K: 547% of the RDI
• Folate: 11% of the RDI
• Potassium: 4% of the RDI

The herb is rich in many vitamins, particularly vitamin K, which is needed for blood clotting and bone health.

Parsley is also a great source of vitamins A and C — important nutrients with antioxidant properties.

Additionally, it’s very low in calories yet packed with flavor, making it a great low-calorie ingredient for many recipes. Rich in antioxidants Parsley contains many powerful antioxidants that can benefit your health.

Antioxidants are compounds that prevent cellular damage from molecules called free radicals. Your body requires a healthy balance of antioxidants and free radicals to maintain optimal health.

The main antioxidants in parsley are:

• flavonoids
• carotenoids
• vitamin C

The fragrant herb is particularly rich in a class of antioxidants known as flavonoids. The two main flavonoids include myricetin and apigenin.

Studies show that diets rich in flavonoids may lower your risk of conditions, including colon cancer, type 2 diabetes, and heart disease.

Furthermore, beta carotene and lutein are two antioxidants known as carotenoids. Many studies associate higher intake of carotenoids with a reduced risk of certain diseases, including lung cancer.

Vitamin C also has strong antioxidant effects and plays an important role in supporting immune health and protecting against chronic disease.

Interestingly, dried parsley may be higher in antioxidants than fresh sprigs. In fact, one study found that the dried herb had 17 times more antioxidant content than its fresh counterpart.

Parsley is packed with vitamin K — an essential nutrient for bone health. A 1/2 cup (30 grams) provides an impressive 547% of the RDI.

Vitamin K helps build stronger bones by supporting bone-building cells called osteoblasts. This vitamin also activates certain proteins that increase bone mineral density — a measure of the amount of minerals present in your bones.

Bone density is important, as a lower bone mineral density is associated with an increased risk of fractures — especially in older adults.

Some studies suggest that eating foods high in vitamin K may reduce your risk of fractures. One study found that higher vitamin K intake was associated with a 22% lower risk of fractures.

Typical dietary intakes of vitamin K may be below the levels needed to improve bone mineral density and reduce fracture risk. Therefore, eating foods like parsley may benefit bone health

Some test-tube studies have shown that oregano and its components may help kill cancer cells.

One test-tube study treated human colon cancer cells with oregano extract and found that it stopped the growth of cancer cells and helped kill them off.

Another test-tube study showed that carvacrol, one of the components in oregano, also helped suppress the growth and spread of colon cancer cells.

However, keep in mind that these were test-tube studies using high amounts of the herb and its compounds. Human studies using typical doses are needed to determine its effects.

In particular, carvacrol and thymol are two compounds in oregano that have been associated with antiviral properties.

In one test-tube study, carvacrol inactivated norovirus, a viral infection that causes diarrhea, nausea and stomach pain, within one hour of treatment.

Another test-tube study found that thymol and carvacrol inactivated 90% of the herpes simplex virus within just one hour.

While these results are promising, additional research on how oregano may impact viral infections in humans is needed. Could Decrease Inflammation

Inflammation is a normal immune response that occurs as a result of illness or injury.

However, chronic inflammation is believed to contribute to the development of diseases like heart disease, diabetes and autoimmune conditions.

Oregano is rich in antioxidants, which can help neutralize free radicals and reduce inflammation.

It also contains compounds like carvacrol that have been shown to have anti-inflammatory properties. In one animal study, carvacrol reduced swelling in the paws of mice by up to 57%.

Another animal study showed that a mixture of thyme and oregano essential oils reduced the number of inflammatory markers in mice with colitis, or an inflamed colon.

Remember that these studies looked at the effects of oregano and its components in highly concentrated amounts. Studies are needed to determine how a normal dose could affect inflammation in humans.