11 Proven Health Benefits of Garlic

“Let food be thy medicine, and medicine be thy food.”

Those are famous words from the ancient Greek physician Hippocrates, often called the father of Western medicine.

He actually used to prescribe garlic to treat a variety of medical conditions.

Well… modern science has recently confirmed many of these beneficial health effects.

Here are 11 health benefits of garlic that are supported by human research studies.

1. Garlic Contains a Compound Called Allicin, Which Has Potent Medicinal Properties

Garlic is a plant in the Allium (onion) family.

It is closely related to onions, shallots and leeks.

It 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 (1).

Its use was well documented by all the major civilizations… including the Egyptians, Babylonians, Greeks, Romans and the Chinese (2).

This is what garlic looks like:

The entire “head” is called a garlic bulb, while each segment is called a clove. There are about 10-20 cloves in a single bulb, give or take.

We now know that most of the health effects are caused by one of the sulfur compounds formed when a garlic clove is chopped, crushed or chewed.

This compound is known as allicin, and is also responsible for the distinct garlic smell.

Allicin enters the body from the digestive tract and travels all over the body, where it exerts its potent biological effects (which we’ll get to in a bit

Bottom Line: Garlic is a plant in the onion family, grown for its cooking properties and health effects. It is high in a sulfur compound called Allicin, which is believed to bring most of the health benefits.

2. Garlic Is Highly Nutritious, But Has Very Few Calories

Calorie for calorie, garlic is incredibly nutritious.

A 1 ounce (28 grams) serving of garlic contains (3):

• Manganese: 23% of the RDA.
• Vitamin B6: 17% of the RDA.
• Vitamin C: 15% of the RDA.
• Selenium: 6% of the RDA.
• Fiber: 1 gram.
• Decent amounts of Calcium, Copper, Potassium, Phosphorus, Iron and Vitamin B1.

Garlic also contains trace amounts of various other nutrients. In fact, it contains a little bit of almost everything we need.

This is coming with 42 calories, with 1.8 grams of protein and 9 grams of carbs.

Bottom Line: Garlic is low in calories and very rich in Vitamin C, Vitamin B6 and Manganese. It also contains trace amounts of various other nutrients.

3. Garlic Can Combat Sickness, Including the Common Cold

Garlic supplementation is 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 with placebo (4).

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

Another study found that a high dose of garlic extract (2.56 grams per day) can reduce the number of days sick with cold or flu by 61% (5).

If you often get colds, then adding garlic to your diet could be incredibly helpful.

Bottom Line: Garlic supplementation helps to prevent and reduce the severity of common illnesses like the flu and common cold.

4. The Active Compounds in Garlic Can Reduce Blood Pressure

Cardiovascular diseases like heart attacks and strokes are the world’s biggest killers.

High blood pressure, or hypertension, is one of the most important drivers of these diseases.

Human studies have found garlic supplementation to have a significant impact on reducing blood pressure in people with high blood pressure (6, 7, 8).

In one study, aged garlic extract at doses of 600-1,500 mg was just as effective as the drug Atenolol at reducing blood pressure over a 24 week period (9).

Supplement doses must be fairly high to have these desired effects. The amount of allicin needed is equivalent to about four cloves of garlic per day.

Bottom Line: High doses of garlic appear to improve blood pressure of those with known high blood pressure (hypertension). In some instances, supplementation can be as effective as regular medications.

5. Garlic Improves Cholesterol Levels, Which May Lower The Risk of Heart Disease

Garlic can lower Total and LDL cholesterol.

For those with high cholesterol, garlic supplementation appears to reduce total and/or LDL cholesterol by about 10-15% (10, 11, 12).

Looking at LDL (the “bad”) and HDL (the “good”) cholesterol specifically, garlic appears to lower LDL but has no reliable effect on HDL (6, 7, 13, 14, 15).

Garlic does not appear to lower triglyceride levels, another known risk factor for heart disease (10, 12).

Bottom Line: Garlic supplementation seems to reduce total and LDL cholesterol, particularly in those who have high cholesterol. HDL cholesterol and triglycerides do not seem to be affected.

6. Garlic Contains Antioxidants That May Help Prevent Alzheimer’s Disease and Dementia

Oxidative damage from free radicals contributes to the ageing process.

Garlic contains antioxidants that support the body’s protective mechanisms against oxidative damage (16) .

High doses of garlic supplementation have been shown to increase antioxidant enzymes in humans (5, 17), as well as significantly reduce oxidative stress in those with high blood pressure (6).

The combined effects on reducing cholesterol and blood pressure, as well as the antioxidant properties, may help prevent common brain diseases like Alzheimer’s disease and dementia (17, 18).

Bottom Line: Garlic contains antioxidants that protect against cell damage and ageing. It may reduce the risk of Alzheimer’s disease and dementia.

7. Garlic May Help You Live Longer

Effects on longevity are basically impossible to prove in humans.

But given the beneficial effects on important risk factors like blood pressure, it makes sense that garlic could help you live longer.

The fact that it can fight infectious disease is also an important factor, because these are common causes of death, especially in the elderly or people with dysfunctional immune systems.