Garlic Vs Onion: Know the Differences & Similarities


Reading Time: 8 minutes

The onion and garlic are some of the most popular Allium vegetables around. They are used to add flavor to savory dishes of all kinds. While these vegetables have many similarities, they differ at many points too.

In the garlic vs. onion debate, you would realize that the former has a more pungent taste than the latter. This is because while garlic bulbs are composed of several cloves, onions bulbs are made of layers.

The purpose of these Allium vegetables is mainly to add flavor to your food. However, they have several health benefits, including acting as antioxidants, cancer prevention, and heart health promotion.

This article discusses the facts about the onion and garlic with the view of helping you make a clear comparison and nutritional differences between the two. Let’s delve right into it!


Garlic is a food loved by many because it enables the preparation of savory dishes. In addition, it has a strong, pungent flavor that makes it a favorite in many traditional cuisines worldwide.

Apart from its key role in the human diet, garlic has been a preferred treatment for illnesses and diseases for millennia. It contains various compounds, minerals, and vitamins that give it a high medicinal and nutritional value.

Garlic Nutritional Facts

Garlic is a highly nutritious food with loads of minerals to meet your daily needs. In addition, it has anti-inflammatory properties and is great to add to your food any time, any day.

Besides, it can bring out the flavor of vegetables and other healthy foods. The following are the garlic nutritional facts in a 1-teaspoon serving based on the U.S Department of Agriculture (USDA):

  • Calories – 4
  • Calcium – 5mg
  • Fat – 0.01g
  • Carbohydrates – 0.93g
  • Protein – 0.18g
  • Fiber – 0.1g
  • Iron – 0.05mg
  • Natural sugars – 0.03g
  • Potassium – 11mg
  • Magnesium – 1mg
  • Vitamin C – 0.9mg

Besides, garlic contains many amino acids and proteins building blocks. It also has enzymes that protect gut health and build muscles across the body.


It is carbohydrates that contribute to the calories in garlic. The carbohydrate content is extremely low at the small serving of 1 teaspoon. There’s only 1 gram of carbs in one garlic clove. In the garlic vs. onion debate, garlic has fewer carbohydrates.

Fats & Proteins

Garlic does not contain the content of fats. That’s one of the reasons why it has a small number of calories. On the other hand, garlic contains some protein but not much to make a big difference.

Minerals and Vitamins

Garlic contains an assortment of vitamins and minerals. However, it would help if you had several garlic cloves to get positive from the vegetable’s vitamin and mineral content.

Each garlic clove has manganese, vitamin K, Vitamin E, magnesium, potassium, iron, calcium, zinc, and vitamin C. Therefore, you can skip fruits and still get a fair share of vitamin C and enjoy its antioxidant properties.


the typical garlic clove weighs 3 grams and contains a negligible number of calories. Taking a whole clove into your diet only adds four calories. Typically, you may not even consume a whole clove. Therefore, the number of calories added by garlic to your diet is negligible.

Garlic Health Benefits

Garlic has potential therapeutic benefits resulting from various bioactive compounds, including organosulfur compounds, polysaccharides, phenol, and saponins.

However, many studies on garlic health benefits are not about the cooked version but one prepared as a supplement.

Even though one of the best medicinal foods, it won’t materialize into the stated health benefits unless consumed in amounts equivalent to the contents of garlic supplements. The following are the health benefits of garlic:

1. Reducing Inflammation

Existing evidence shows that garlic is high in anti-inflammatory properties that enable it to reduce inflammation. In one study, subjects received 400mg of garlic extract twice daily. They were shown to reduce inflammation and boost the immune system significantly.

2. Lowering Cholesterol Levels

Garlic also has proven effects on high cholesterol. A group of people with diabetes received garlic extract and olive oil and experienced reduced triglycerides and cholesterol levels.

Garlic was given to these patients in powdered and non-powdered form for three months. In the end, garlic increased good cholesterol while lowering bad cholesterol.

3. Antioxidant Properties

Garlic contains antioxidants, which reduce free radicals, preventing oxidative stress. It is the phenol compounds in garlic that reduce oxidative stress. The process reduces the chances of cardiovascular disease in obese patients by preventing blood clotting.

4. Improving Heart Health

Garlic can lower blood pressure, helping patients with high blood pressure, hypertension, atherosclerosis, diabetes, myocardial infarction, hyperlipidemia, and ischemic stroke.

Negative Effects of Garlic

Despite its many health benefits, garlic also has several negative effects, albeit very mild. Here are some of the disadvantages of garlic:

  • Allergies: Garlic may cause allergies when consumed by some people. Reactions may occur upon exposure to, contact with, or ingest garlic. Allergic symptoms include skin welts, breathing difficulty, stuffy nose, and red or swollen skin.
  • Watery Eyes: An enzyme in garlic causes eyes to water. It is released by slicing or chopping garlic cloves. In the onions vs. garlic debate, allium vegetables share this characteristic.
  • Bad Breath: Garlic’s strong, pungent taste may cause bad breath. It gets worse if you consume raw garlic instead of its cooked version.

Garlic Varieties

Garlic exists in hundreds of varieties, with the most common two being the silverskin and artichoke. The artichoke variety of garlic has overlapping layers of cloves and closely resembles artichokes.

When Is It Best?

The best time to use garlic is when it’s still fresh. When it softens, browns, or sprouts, steer clear from it.

Storage and Food Safety

Safety handling of garlic starts with the selection of fresh bulbs from the grocery store. Once you reach home, store the fresh garlic in a mesh or wire container at room temperature. Do not use plastic bags. Finally, leave the tops intact.


The onion (Allium cepa) is one of the Allium vegetables and comes in the form of bulbs. Several types of onions exist, including leeks, shallots, scallions, and chives.

Onions have several health benefits due to their impressive antioxidant and anti-inflammatory properties. In addition, they are linked with lower blood sugar levels, reduced risk of cancer, and improved bone health.

You can eat onions raw or cooked as part of traditional cuisines worldwide. Onions can be eaten raw, powdered, sauteed, roasted, fried, grilled, boiled, or baked.

The onion comes in various shapes, colors, and sizes. Commonly, you’ll encounter red, yellow, or white onions. They have a mild, sweet, or sharp taste, depending on the variety of onions in question.

Onion Nutrition Facts

A medium-sized onion weighs 110g, approximately 44 calories, 10.3g of carbohydrates, 1.2g of protein, and 0.1 fat. Raw onion is great in supplying the body with manganese, folate, potassium, vitamin B6, and Vitamin C.

Here is a summary of the onion nutritional information, according to the USDA:

  • Calories – 44
  • Carbohydrates – 10.3g
  • Diet fiber – 1.9g
  • Fat – 0.1g
  • Sodium – 4.4mg
  • Sugars – 4.7g
  • Vitamin C – 8.1mg
  • Protein – 1.2g
  • Folate – 20.9mcg
  • Potassium – 161mg
  • Vitamin B6 – 0.1mg
  • Manganese – 0.1mg


Whether raw, cooked, or onion powder, this spicy plant has 9% to 10% carbohydrates. A medium onion has 10g of carbohydrates, 4.7g is sugar, and 1.9g of dietary fiber.

Furthermore, the onion’s low glycemic index makes it a great addition to a diabetic diet. In the onions vs. garlic debate, onions have more carbs.

Dietary Fiber

Onions have a decent dietary fiber content ranging from 0.9% to 2.6% of the weight of fresh onion. The actual proportion of dietary fiber depends on the onion type.

The onion mainly contains fructans, a type of healthy soluble fiber. Very few vegetables contain this type of fiber.

Fructans promote gut health by acting as food for probiotics whose presence reduces inflammation, promotes colon health, and reduces cancer risk.


When eaten raw or in powder form, the onion has negligible amounts of fat. However, since they’re prepared with olive oil, butter, or salad dressing, eating onions may contribute to an increased intake of saturated fats.


The protein content in onions is about 1g per serving. So the onion and garlic won’t contribute significant amounts of garlic to your diet.

However, onions can add flavor to protein-containing foods like lean meat and eggs, helping you improve your protein uptake.

Vitamins and Minerals

Onions have several vitamins and minerals, including manganese, potassium, folate, vitamin B6, and vitamin C. Even though in small amounts, the onion and garlic have some choline and selenium. Copper, zinc. Phosphorus, magnesium, iron, and calcium.

Here is a description of some of the main nutrients in onions:

  • Vitamin B6: The importance of vitamin B6 is to help the body form red blood cells.
  • Potassium: In the human diet, potassium is essential in lowering high blood pressure, thus improving heart health.
  • Folate (B9): Vitamin B9 is another great nutrient found in the onion. It helps in cell growth and increases metabolism. Pregnant women need it in substantial amounts.
  • Vitamin C: Vitamin V is an antioxidant necessary for improving the immune system and maintaining hair and skin health.


Onions seem to have more calories than garlic, focusing on the garlic vs. onion debate. From a medium-sized (2.5-inch diameter) 110g onion, you can expect up to 44 calories.

From a thin onion slice (9g), you’ll get 3.6 calories, and a thick slice (38g) 15 calories. However, the onion and garlic contribution to the daily caloric intake is negligible.

Onion Health Benefits

According to modern science, onions have medicinal and health benefits. They can improve the immune system remove toxins, and reduce blood pressure. The following are the various ways onions can be beneficial to your health:

1. Fighting Heart Disease

The onion and garlic contain organosulfur compounds, which help prevent the onset of heart disease. As an antioxidant, vitamin C helps remove toxins from the body, helping you maintain good heart health.

2. Preventing Cancer

The sulfides in onions are also crucial in protecting the body against the onset of cancer. They regulate some of the most obvious ways cancer gets into the body. The sulfides can induce apoptosis, prevent cancer cell migration, and arrest the cell cycle.

3. Regulating Body Weight

Studies conducted on the effects of onion extract on animal body weight found that onions can help reduce weight gain. The active compounds in onions were established to reduce body weight in humans.

4. Supporting Male Fertility

Studies on onion peel extract established that it can make the Hv1 channel more active. The Hv1 plays a role in the production of sperms in men. It has been established that the strength of onion peel extract is so strong it can result in developing infertility medication.

5. Improving Memory

One of the most impressive onions’ contents is inulin, a soluble fiber that acts as food for healthy gut bacteria. Apart from improving gut health, inulin can cause better memory. In the garlic vs. onion discussion, both Allium vegetables have inulin content.

Onion Negative Effects

It might have many health benefits, but the onion has several negative effects. The following are some of how onions can be detrimental:

  • Allergies: Onions can cause allergic symptoms like runny nose, skin rash, and asthma. However, these symptoms do not come as a result of ingesting onions but as handling them. Cooked onions may cause anaphylaxis, a form of food allergy.
  • Irritating to the Eyes: Cutting onions may release enzymes, irritating the eyes. In the process, one may develop teary eyes. In the garlic vs. onion debate, onions are more irritating to the eyes.
  • Bad Breath: Eating onions raw can render your breath smell bad. Besides, the sulfurous compounds in the onions can be released through sweat, making you smell bad.
  • Irritable Bowel Syndrome: The fructans in onions have a FODMAP effect, leading to irritable bowel syndrome, which causes gas, bloating, and abdominal pain.
  • Effect on Blood Sugar Medication: onions naturally regulate blood sugar and may affect the dosage of diabetes drugs one should take.

Onion Varieties

When discussing onions vs. garlic, it’s important to note that the former has the largest number of varieties. In addition, onions can be red, white, or yellow. Depending on their chemical composition, onions may vary in taste even within the same color.

Apart from fresh onions, you can purchase onion powder or dehydrated onions. Any of these are great for adding flavor to your food. Apart from the bulb onions, other varieties include scallions or green onions. They are available for use as green leaves and minuscule bulbs.

When is it Best?

You can find onions in the local grocery store throughout the year. When selecting onions, choose those without cuts and bruises.

Also, ensure that the onions are firm and not too soft. For pre-cut onions, avoid those looking slimy or dried out. Always ensure you use your onions before the stated expiry date.

Storing and Preparing Onions

Fresh onions are best used within two to four weeks of buying from the store. Keep unused onions in a cool, dry, well-ventilated place. Before cutting onions, wash them under running water.

After slicing onions, store them in a refrigerator for 7 days. Signs of mold should indicate the need to discard the onions.

You pay chop onions in half-inch or quarter-inch sections to keep in a freezer. Sliced, washed, and peeled onions don’t require blanching before freezing.

After freezing onions on a baking sheet, place them in an airtight container. You can remove a few pieces whenever you need onions according to your needs.

People Also Ask

Is Garlic and Onion the Same?

The Allium family includes both garlic and onion, but they have different tastes and are used for different recipes. So, they are not the same.

Is There a Cross Between an Onion and Garlic?

To clarify, onions and garlic are not a hybrid of each other. They are distinct vegetables belonging to the Allium family. While onions have a sweet taste, garlic has a strong and sharp flavor.

What Garlic Does to the Body?

Garlic is very beneficial to human health. It has the ability to decrease cholesterol and blood pressure, minimize the possibility of cancer, stabilize blood sugar, enhance immune system function and blood flow. Furthermore, garlic can help combat bacteria and viruses.





Leave a Comment