Garlic can boost metabolism, reduce body fat, and improve body composition while also promoting heart health, immunity, and anti-inflammatory effects. It may even help regulate blood sugar levels.
However, overconsumption or sensitivity to garlic can lead to digestive discomfort, bad breath, or interactions with medications. Moderation and quality are key to reaping its benefits while minimizing potential downsides.
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History
Garlic has a rich history of culinary and medicinal use, dating back thousands of years. It is believed to have originated in Central Asia, but its cultivation and use spread early to the Mediterranean region, where it became a dietary and cultural staple. In ancient Mediterranean civilizations, garlic was valued not only for its flavor but also for its health-promoting properties.
Garlic in Ancient Mediterranean History
Garlic was a key component of the diet in Ancient Egypt. Workers who built the pyramids were fed garlic to boost their strength and stamina. It was also considered sacred, often included in burial rituals, and found in tombs like that of King Tutankhamun.
In Ancient Greece, garlic was widely used as both food and medicine. Athletes in the original Olympic Games consumed garlic to enhance their performance.
Hippocrates, the “Father of Medicine,” recommended garlic for treating respiratory issues, parasites, and poor digestion.
The Romans continued this tradition, incorporating garlic into their diets, particularly among soldiers, who believed it gave them courage and endurance.
Across the region, garlic was used in folk remedies to ward off illness and even as protection against “evil spirits.” It was also thought to have antiseptic properties, making it a useful treatment for infections.
Garlic in the Traditional Mediterranean Diet
In the traditional Mediterranean diet, garlic plays an essential role both as a flavor enhancer and a functional food. It is commonly used in a variety of dishes, such as stews, soups, and sauces like allioli in Spain or skordalia in Greece. Its pungent flavor complements staples of the Mediterranean diet, including olive oil, tomatoes, herbs, and legumes.
Garlic also aligns with the diet’s focus on health-promoting, natural ingredients. It contains allicin, a sulfur compound responsible for its strong aroma and many of its health benefits, such as cardiovascular protection, immune support, and antimicrobial properties. This made it an ideal ingredient in a diet focused on longevity and overall well-being.
Today, garlic remains a cornerstone of Mediterranean cuisine, symbolizing its long-standing culinary and medicinal traditions. Its ancient roots highlight its significance not only as a flavorful addition to food but also as a revered health-promoting ingredient throughout the history of the Mediterranean region.
Benefits of Garlic for Weight Loss
Garlic has been linked to potential benefits for weight loss due to its bioactive compounds and ability to influence metabolic processes.
One of its primary components, allicin, plays a crucial role in promoting fat loss and improving overall metabolic function. Garlic can help reduce body weight by stimulating the breakdown of stored fat, enhancing thermogenesis (the body’s ability to burn calories for heat), and suppressing appetite by promoting feelings of fullness.[1]
Another way garlic helps is by stimulating brown adipose tissue, a type of fat that burns triglycerides to produce heat, a process known as thermogenesis. This increased thermogenesis can aid in reducing belly fat and promoting weight loss.[2]
Other factors, such as exercise and compounds like melatonin and resveratrol, can also enhance brown adipose tissue activity. Foods like red wine, berries, and peanuts are excellent natural sources of resveratrol.[3]
Additionally, garlic may help combat obesity and reduce waist circumference by influencing certain genes that regulate fat storage.[4]
It also activates the AMPK enzyme, which boosts energy expenditure. This enzyme is similarly activated through exercise and calorie restriction, further emphasizing the synergy between garlic consumption and a healthy lifestyle.[5]
Additionally, garlic’s ability to regulate blood sugar levels helps prevent spikes and crashes in energy, which can reduce cravings for unhealthy foods.
Moreover, garlic has anti-inflammatory properties that may address chronic inflammation, often associated with obesity and weight gain. By reducing inflammation, garlic can improve hormonal balance, particularly leptin and insulin sensitivity, which are crucial for weight management.
While garlic alone isn’t a magic solution for weight loss, it can be an effective complement to a healthy diet and active lifestyle.
Garlic for a Lean Body
Including garlic in a hypocaloric diet can not only aid in reducing body weight but also help lower body fat percentage.[6]
Notably, garlic consumption appears to protect valuable muscle mass. When losing weight, we often lose both fat and muscle, but preserving as much muscle as possible is essential. Greater muscle mass is linked to higher energy expenditure and improved metabolism. Resistance exercise during dieting is also vital for maintaining lean body mass.
Research suggests that combining garlic intake with exercise is more effective at reducing body weight and burning belly fat than exercise alone.[7]
Additionally, garlic consumption may help reduce waist circumference and improve overall body composition.[8]
General Health Benefits of Garlic
Garlic is a powerhouse of nutrients and bioactive compounds that provide numerous health benefits. Here are its most notable effects:
Immune System Boost: Garlic has antiviral, antibacterial, and antifungal properties, thanks to allicin and other sulfur compounds. Regular consumption can help strengthen the immune system, reducing the risk of colds, flu, and infections.
Antioxidant Properties: Garlic is rich in antioxidants that help combat oxidative stress and reduce free radical damage, protecting cells from aging and lowering the risk of chronic diseases such as cancer and Alzheimer’s.
Anti-inflammatory Effects: Garlic can reduce inflammation throughout the body, which is linked to conditions such as arthritis, diabetes, and heart disease.
Blood Sugar Regulation: Garlic improves insulin sensitivity and helps regulate blood sugar levels, making it beneficial for people with type 2 diabetes or those at risk of developing the condition.
Detoxification: Garlic supports liver function and helps eliminate toxins and heavy metals from the body. Its sulfur compounds aid in activating liver enzymes that flush out harmful substances.
Digestive Health: Garlic promotes a healthy gut by supporting the growth of beneficial bacteria and reducing harmful bacteria. It can improve digestion and help prevent gastrointestinal infections.
Cancer Prevention: Studies suggest that regular garlic consumption may reduce the risk of certain cancers, particularly stomach and colon cancer, due to its ability to inhibit the growth of cancerous cells and repair DNA.
Heart Health
Garlic supports cardiovascular health by lowering LDL cholesterol (the “bad” cholesterol) and raising HDL cholesterol (the “good” cholesterol). It helps reduce blood pressure, improve blood circulation, and prevent the buildup of plaque in arteries, thereby reducing the risk of heart disease and stroke.[9]
According to studies, garlic intake can reduce total serum cholesterol by 17 mg/dL! Most noteworthy, garlic can naturally reduce LDL-cholesterol by 9 mg/dL, while slightly increasing HDL-cholesterol levels.[10]
Garlic could help reduce high blood pressure. Garlic supplements are as effective in reducing high blood pressure as standard antihypertensive medications! According to studies, garlic supplements can lower systolic and diastolic blood pressure by an average of 8-10 mmHg and 5-6 mmHg, respectively.[11]
This reduction in blood pressure significantly reduces the risk of cardiovascular events, such as heart attack and stroke, by up to 40%.
Hypertension affects one in three adults worldwide! Most of them don’t even know it. Hence, we should regularly check our blood pressure. It’s one of the major risk factors for cardiovascular disease, including coronary artery disease. By controlling high blood pressure, we can control the progression of coronary artery disease.[12]
Also, garlic reduces high blood pressure because it increases the production of nitric oxide. Nitric oxide is a molecule that can reduce high blood pressure. It protects the heart and improves endothelial function. Also, it has antidiabetic effects.[13,14]
Moreover, garlic is beneficial for gut microbiota. Low diversity or population of gut microbiota can cause hypertension! Garlic can restore the microbiota biofilm and mucus production, due to its prebiotic properties and hydrogen sulphide (H2S) production.
Last but not least, garlic produces hydrogen sulphide when interacts with red blood cells. This compound relaxes blood vessels, lowering high blood pressure.[15]
Regular moderate exercise, weight loss, and following a healthy diet could really help regulate hypertension, along with dietary supplements and medication.
Types of Garlic
Garlic, in all its forms—raw, powdered, roasted, aged, or as garlic oil—offers a range of health benefits, but the effectiveness can vary slightly depending on the form:
- Raw garlic retains the most allicin, the active compound responsible for many of its health benefits, including its metabolism-boosting and fat-burning properties. Consuming raw garlic is ideal for maximum health benefits, but it has a strong flavor that some may find challenging.
- Garlic powder is a convenient option and still contains beneficial compounds, though its allicin content may be lower due to processing. It’s excellent for cooking and seasoning while keeping calories low.
- Roasted or cooked garlic reduces its allicin content, but it still provides antioxidants and other nutrients. It’s also more palatable for people who prefer a milder flavor.
- Aged garlic extract is often used in supplements and is known for its potent antioxidant and heart health benefits. While less relevant for weight loss, it’s highly beneficial for overall health.
- Garlic-infused oil is great for flavoring dishes but may contain fewer active compounds. Use it sparingly as part of your healthy fat intake.
How to Incorporate Garlic into your Mediterranean Diet
In Salads and Dressings: Mince raw garlic and mix it into olive oil and lemon juice for a flavorful and nutrient-packed dressing. This combination enhances the absorption of fat-soluble vitamins in vegetables.
As a Cooking Ingredient: Add garlic powder or fresh minced garlic to soups, stews, and sautéed vegetables. Garlic pairs exceptionally well with Mediterranean staples like tomatoes, eggplant, and legumes.
In Dips and Spreads: Incorporate garlic into hummus, tzatziki, or babaganoush for a delicious, healthy spread rich in protein and fiber.
Roasted Garlic: Roast whole garlic cloves and use them as a creamy, sweet spread on whole-grain bread or as a topping for vegetables.
As a Morning Boost: For raw garlic benefits, chop a clove into small pieces and swallow with water or add it to a savory yogurt dip, paired with cucumber or dill.
Garlic Powder as a Seasoning: Sprinkle garlic powder over grilled fish, roasted chicken, or Mediterranean-style baked potatoes for a low-calorie flavor boost.
Combine with Herbs: Mix garlic with oregano, thyme, or parsley for classic Mediterranean seasoning blends that can be used in various dishes.
Garlic combined with extra virgin olive oil enhances health benefits and fits perfectly into the Mediterranean diet.
How much Garlic should you Eat per day?
The optimal amount of garlic depends on its form and individual tolerance. In general:
- Raw Garlic: Eating 1-2 fresh cloves per day (approximately 2-4 grams) is sufficient for most health benefits. More than this may lead to digestive discomfort or bad breath for some people.
- Garlic Powder: Studies suggest 0.3-1 gram per day of garlic powder is beneficial. This equates to about ⅓ to ½ teaspoon. Garlic powder is more concentrated than fresh garlic but contains fewer bioactive compounds.
- Aged Garlic Extract: Research typically uses doses of 600-1,200 milligrams per day, commonly available in supplements.
- Garlic Oil: Use sparingly, as it is highly concentrated. A few drops (around 2-5 milligrams) per dish are usually sufficient.
Portion Sizes of Garlic
- 1 teaspoon of minced garlic equals about 2-3 grams of raw garlic or roughly one small clove.
- 1 tablespoon of minced garlic equals 3 teaspoons or 6-9 grams.
- 1 teaspoon of garlic powder weighs about 2.8 grams, which is equivalent to approximately 6-8 fresh cloves.
Dosages Used in Studies
Research typically uses a wide range of garlic dosages (0.3-20 grams per day), depending on the form and the study’s focus. For practical purposes:[16]
- For cardiovascular benefits, around 4 grams (1-2 cloves) of raw garlic or 600-1,200 mg of aged garlic extract daily is often recommended.
- For weight loss or anti-inflammatory effects, 2-6 grams of raw garlic or 1 gram of garlic powder is commonly used.
Tips for Incorporating Garlic in Daily Life
- Start Small: Begin with a smaller amount (e.g., 1 clove or ½ teaspoon of powder) and gradually increase to avoid stomach upset.
- Balance Your Intake: Too much garlic can cause bloating, heartburn, or bad breath, so aim for moderation.
- Use Different Forms: Rotate between fresh garlic, garlic powder, and aged extract to enjoy a variety of benefits.
Choosing the Best Garlic Supplement
When selecting a garlic supplement, consider the following:
Aged Garlic Extract
Aged garlic extract (such as Kyolic) is widely studied and provides consistent benefits, particularly for heart health, blood pressure, and inflammation. Most studies use 600-1,200 mg of aged garlic extract daily, divided into two doses.
Garlic Oil or Powder Capsules
These provide concentrated garlic compounds like allicin but may vary in quality. Look for standardized allicin content. Aim for capsules with 1-3 mg of allicin or equivalent per serving.
Deodorized Garlic Supplements
Deodorized options reduce the strong taste and smell but may contain fewer active compounds. Check labels to ensure the supplement provides a standardized dose of allicin or S-allyl cysteine (SAC).
Whole Garlic Supplements
These mimic fresh garlic and contain various beneficial compounds. However, their bioavailability may be lower than aged garlic extract.
How much Garlic Supplement should you take?
The appropriate dosage depends on the type of supplement:
- Aged Garlic Extract: Take 600-1,200 mg daily, divided into two doses (e.g., 600 mg in the morning and evening).
- Garlic Powder Capsules: Typically, 400-600 mg twice a day is recommended. Look for supplements standardized for 5,000-6,000 mcg of allicin potential per day.
- Garlic Oil Capsules: Usually, 1-2 softgels daily are sufficient, providing about 1-3 mg of allicin.
- Deodorized Garlic Tablets: Follow the manufacturer’s dosage recommendations, as allicin content may vary.
Tips for choosing high-quality Supplements
- Look for products with a guaranteed allicin yield or standardized S-allyl cysteine content.
- Choose supplements tested by third-party organizations like USP, NSF, or ConsumerLab for purity and quality.
- Avoid products with unnecessary fillers or artificial ingredients.
- Popular brands like Kyolic, Nature’s Way, and NOW Foods are known for producing high-quality garlic supplements.
General Guidelines
- Start with the lower end of the recommended dosage to assess tolerance.
- Take garlic supplements with food to reduce the risk of stomach upset.
- Consult a healthcare provider before taking garlic supplements, especially if you’re on blood-thinning medications, have a bleeding disorder, or are pregnant or breastfeeding.
You can find odorless garlic concentrated extracts, garlic oils, or aged garlic extracts, which have enhanced bioactivity on iHerb.
Dangers of Garlic Consumption
Digestive Issues
Garlic, especially raw, can be harsh on the digestive system. Consuming too much may cause bloating, gas, heartburn, nausea, or diarrhea. People with sensitive stomachs or gastrointestinal conditions, such as irritable bowel syndrome (IBS), may find garlic particularly irritating.
Bad Breath and Body Odor
Garlic contains sulfur compounds like allicin, which are responsible for its strong smell. These compounds can linger in your mouth and sweat, causing unpleasant breath and body odor, even hours after consumption.
Allergic Reactions
Though rare, some individuals may experience allergic reactions to garlic. Symptoms may include skin rashes, hives, swelling, or difficulty breathing. If you suspect an allergy, avoid garlic and seek medical advice.
Blood-Thinning Effects
Garlic has natural anticoagulant properties, which can increase the risk of bleeding. This can be dangerous for individuals on blood-thinning medications (e.g., warfarin, aspirin) or those scheduled for surgery. Even small amounts, particularly in supplement form, can enhance these effects.
Drug Interactions
Garlic can interact with medications, potentially reducing their effectiveness or increasing their side effects. For example:
- Anticoagulants: Increased risk of bleeding.
- Blood Pressure Medications: Garlic may amplify their effects, causing blood pressure to drop too low.
- HIV Medications: Garlic supplements, particularly raw forms, may interfere with the effectiveness of certain antiretroviral drugs.
Overconsumption Risks
Garlic is healthy in moderation, but excessive consumption can be harmful. Overeating garlic can lead to gastrointestinal distress, lower blood pressure to unhealthy levels, or contribute to other health issues.
Skin Burns
Direct application of raw garlic on the skin, often used as a home remedy for conditions like acne or warts, can cause chemical burns or irritation. Always use diluted forms and exercise caution.
Impact on Thyroid Health
Excessive garlic consumption may impact thyroid function in individuals with iodine deficiency or hypothyroidism. It may interfere with iodine uptake, potentially worsening thyroid-related issues.
Low Blood Sugar
Garlic can lower blood sugar levels, which may be risky for people with diabetes who are taking medications to manage blood glucose. Monitor your levels closely if consuming garlic regularly.
Contamination in Supplements
Garlic supplements, particularly low-quality ones, may be contaminated with harmful substances or contain less active compounds than advertised. Some may also include additives or preservatives that could cause side effects.
Risk of Botulism in Garlic Oil
Homemade garlic oil stored at room temperature is at risk of developing Clostridium botulinum bacteria, which can cause botulism—a serious and potentially fatal condition. Always refrigerate garlic oil and use it within a few days.
Fake or Adulterated Products
Counterfeit garlic supplements or adulterated garlic oils can pose health risks. Adulterated products may contain lower-quality oils or chemicals that could cause allergic reactions or toxicity.
Pregnancy and Breastfeeding Concerns
While garlic is generally safe during pregnancy and breastfeeding in moderate food amounts, excessive consumption (especially supplements) may lead to digestive discomfort, increased bleeding risk, or changes in breast milk flavor.
To enjoy garlic safely, consume it in moderation, opt for high-quality products, and consult a healthcare provider if you have medical conditions or take medications.