The Health Benefits of Garlic: What the Evidence Really Says

Maybe it is because I am Italian, but I absolutely love garlic. Especially raw garlic. I put it everywhere!

And yes, I know that not everyone feels the same way. Some people find raw garlic difficult to digest, while others worry about the inevitable garlic breath.

My solution to the latter is very simple: get your partner and everyone around you to eat garlic too. Then nobody can smell it!

Joking aside, garlic is a fascinating food. It has been used in cooking and traditional medicine for centuries, and modern research has taken a particular interest in its sulphur-containing compounds, including allicin.

But there is quite a lot of exaggerated information about garlic online. So, what are the health benefits of garlic that we can actually support with evidence?

Is garlic good for you?

Yes. Garlic is a nutritious, low-calorie ingredient that adds plenty of flavour to meals, while also providing compounds that have been studied for their potential cardiovascular and antimicrobial effects.

Some of the strongest human evidence relates to garlic preparations and cardiovascular risk factors such as blood pressure and cholesterol. However, many studies use concentrated garlic extracts or supplements, so we should not automatically assume that eating a clove of garlic will produce the same effect.

For me, that’s another reason to enjoy garlic as part of normal, fresh cooking rather than thinking of it as a medicine.

What makes garlic interesting?

Garlic belongs to the Allium family, alongside onions, leeks, shallots and chives.

Its distinctive smell and flavour come largely from sulphur-containing compounds. One of the best known is allicin, which forms when garlic is chopped, crushed or otherwise damaged. The enzyme alliinase helps convert compounds naturally present in the intact clove into allicin.

This is one reason freshly crushed garlic is so pungent.

And that pungency isn’t just about flavour. Garlic’s organosulphur compounds are the subject of considerable scientific research because of their biological activity.

Garlic and heart health

This is probably the area where the human evidence is most interesting.

Several clinical studies and meta-analyses have investigated garlic’s effect on cardiovascular risk factors. A large 2025 systematic review and meta-analysis of 108 randomised controlled trials found that garlic interventions were associated with modest improvements in several measures, including total cholesterol, LDL cholesterol and blood pressure.

A 2024 meta-analysis of 21 randomised controlled trials also found reductions in total cholesterol, triglycerides and LDL cholesterol among people with dyslipidaemia.

There is an important distinction here, though.

Much of this research involves garlic preparations or supplements, sometimes at doses that are quite different from the amount you would use to cook dinner. So I would not suggest taking garlic as a replacement for prescribed cholesterol or blood-pressure medication.

Instead, think of garlic as one small part of a heart-friendly dietary pattern.

And fortunately, it makes healthy food taste much better.

What about garlic and blood pressure?

Garlic has also been studied in people with high blood pressure.

Meta-analyses have found that some garlic preparations can produce modest reductions in blood pressure, particularly in people who already have hypertension. However, the studies vary considerably in their garlic preparations, doses and participants.

So this is another area where I would be careful about making promises.

Garlic is a lovely ingredient to include in a balanced diet, but it isn’t a substitute for medical treatment if you have high blood pressure.

Garlic has antimicrobial properties — but don’t confuse this with treating an infection

Garlic has a long history of being associated with fighting infections, and there is a scientific reason why this idea has persisted.

Compounds found in garlic, particularly allicin and related sulphur compounds, have demonstrated antibacterial, antifungal and antiviral activity in laboratory and preclinical research.

But there is a big difference between showing that a compound can inhibit microorganisms in a laboratory and demonstrating that eating garlic will treat an infection in a person.

That’s why I would not recommend using garlic as a replacement for appropriate treatment for conditions such as athlete’s foot, a bacterial infection or a vaginal yeast infection.

There has been some research into specific garlic-derived preparations. For example, one older clinical study found that a topical cream containing ajoene, a garlic-derived compound, was effective against tinea pedis (athlete’s foot). That is interesting research, but it isn’t the same thing as rubbing raw garlic onto your feet.

Can garlic help prevent a cold?

This is one of those claims that sounds convincing because garlic has such a strong reputation for being antimicrobial.

Unfortunately, the clinical evidence isn’t strong enough to say that garlic prevents or treats the common cold.

A Cochrane review found insufficient clinical trial evidence to support the use of garlic for preventing or treating colds. Only one trial met the review’s inclusion criteria, so much more research would be needed before we could draw firm conclusions.

So by all means add garlic to your winter soups, stews and roasted vegetables. Just don’t rely on it as a treatment if you become unwell.

Garlic and your gut

Here’s an interesting one, particularly if you are interested in gut health.

Garlic contains fructans, a type of carbohydrate within the FODMAP group. Fructans can be fermented by gut bacteria and, in people with IBS or particular sensitivities, may contribute to symptoms such as bloating, abdominal discomfort, wind or diarrhoea.

That doesn’t mean garlic is “bad for your gut”.

Quite the opposite: garlic contains prebiotic compounds that can interact with the gut microbiota. The issue is that a food can be perfectly nutritious and still trigger symptoms in someone who is sensitive to it.

This is why I don’t believe in taking a one-size-fits-all approach to nutrition.

If garlic leaves you feeling uncomfortable, you don’t need to force yourself to eat it simply because you’ve read that it is healthy.

Interestingly, garlic-infused oil can provide garlic flavour without the fructans transferring into the oil, because fructans are water-soluble rather than fat-soluble. This can be useful for people following a low-FODMAP approach.

What vitamins and minerals are in garlic?

Garlic is used in relatively small amounts, so it isn’t realistic to think of a couple of cloves as your main source of vitamins and minerals.

Nevertheless, it does provide a useful range of nutrients.

Raw garlic contains:

• Vitamin C
• Vitamin B6
• Vitamin B1 (thiamine)
• Vitamin B2 (riboflavin)
• Folate
• Manganese
• Calcium
• Potassium
• Phosphorus
• Iron
• Selenium
• Copper

It is particularly notable for vitamin B6, vitamin C and manganese when considered on a per-100g basis.

One correction to my original article is worth making here: garlic does not naturally contain vitamin B12. Vitamin B12 occurs naturally in foods of animal origin; plant foods generally only provide it when they have been fortified.

And remember that nobody is realistically eating 100g of garlic at a sitting. A clove weighs only a few grams, so think of these nutrients as a useful bonus rather than the main reason to eat garlic.

Raw garlic or cooked garlic?

This is where my personal preference probably shows!

I love raw garlic, particularly finely chopped into salads, dressings, dips and sauces.

When garlic is chopped or crushed, the process helps form allicin, which is one of the compounds responsible for its characteristic smell and flavour. Heat can affect the enzymes involved in allicin formation, which is one reason raw or freshly crushed garlic has attracted so much attention.

However, I wouldn’t tell you that you must eat garlic raw to be healthy.

If raw garlic gives you heartburn, bloating or stomach discomfort, cook it.

If you enjoy cooked garlic, use it. And if you prefer a milder flavour, roast it.

The best food is usually the food you enjoy and can comfortably include as part of your normal diet.

If you do want to make the most of freshly crushed garlic, try chopping or crushing it shortly before adding it to your meal rather than cooking it immediately.

How to use garlic in your everyday diet

This is the easy part.

You don’t need complicated garlic remedies. Just use it in your normal cooking.

Try:

• finely chopped raw garlic in salad dressings;
• garlic and extra virgin olive oil with roasted vegetables;
• crushed garlic stirred into hummus;
• garlic with tomatoes, herbs and olive oil;
• garlic in soups and stews;
• roasted garlic mashed into vegetables;
• garlic added towards the end of cooking for a stronger flavour;
• garlic-infused oil if you need to avoid the fructans in whole garlic.

And if you are one of those people who can happily eat raw garlic, enjoy it.

Just perhaps check that everyone else at the dinner table is joining you!

What about garlic supplements?

Garlic supplements are widely available, and some of the research showing effects on cholesterol and blood pressure has involved concentrated garlic preparations rather than ordinary culinary garlic. That doesn’t mean supplements are necessary.

For most people, I would start with food. There is something very satisfying about getting your nutrients and plant compounds from a varied diet rather than automatically reaching for a capsule.

Supplements can also have pharmacological effects. Garlic supplements may increase bleeding risk and can interact with medicines, including anticoagulants and other medicines that affect bleeding.

So if you take regular medication, particularly blood-thinning medication, or you are preparing for surgery, speak to your doctor or pharmacist before taking a garlic supplement.

Are there any downsides to garlic?

For most people, garlic used in normal culinary quantities is perfectly reasonable.

The biggest issue is often digestive tolerance.

Raw garlic can cause heartburn, abdominal discomfort, flatulence or nausea in some people, and these effects may be more noticeable when larger amounts are consumed.

People with IBS may also find that garlic’s fructans trigger digestive symptoms.

And then, of course, there is the breath!

Garlic’s volatile sulphur compounds are responsible for that unmistakable smell, which can linger well after you’ve finished eating. Personally, I think that’s a small price to pay.

Dania’s nutritionist tip

My advice with garlic is much the same as my advice with most foods: you don’t need to turn something healthy into a challenge.

If you love garlic, use it generously in your cooking. If you prefer it cooked, cook it. But if raw garlic doesn’t agree with you, don’t force it.

And please don’t feel that you need to eat several cloves of raw garlic every day because you’ve read that more must mean better.

There isn’t a magic number of cloves that everyone needs.

A varied diet full of vegetables, fruit, whole grains, legumes, nuts, seeds, good-quality protein and healthy fats will always be more important than any individual ingredient.

Garlic is simply a delicious addition to that bigger picture.

Final thoughts

Garlic isn’t a miracle food — and it doesn’t need to be.

What I love about it is that a small amount can completely transform a meal. It makes vegetables more interesting, adds flavour to simple dishes and gives you a range of nutrients and naturally occurring plant compounds at the same time.

So if, like me, you love garlic, keep using it.

And if you’re not keen on it raw, don’t worry. There are plenty of delicious ways to enjoy it cooked.

Good nutrition isn’t about finding one perfect food. It’s about creating a varied, enjoyable way of eating that works for you.

Looking for personalised nutrition support?

If you’re trying to improve your nutrition but feel overwhelmed by conflicting advice, personalised support can make the process much simpler.

I work with women over 40 who want to build healthier eating habits around their real lives — without restrictive diets or unrealistic rules.

If you’d like help creating a practical nutrition and lifestyle plan that works around your work, family and everyday commitments, get in touch to discuss how I can help.

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References and resources

1. Behrouz V, Zahroodi M, Clark CCT, et al. (2026). Effects of Garlic Supplementation on Cardiovascular Risk Factors in Adults: A Comprehensive Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrition Reviews, 84(1), 1–35.
   This recent systematic review and meta-analysis examined 108 randomised controlled trials involving more than 7,000 participants and provides the most up-to-date evidence on garlic supplementation and cardiovascular risk factors.
   Read the study on PubMed
2. National Center for Complementary and Integrative Health (NCCIH). Garlic: Usefulness and Safety.
   A useful overview of the evidence surrounding garlic supplements, including cholesterol, blood pressure, immune function, side effects and potential interactions with medicines.
   Read the NCCIH garlic guidance
3. Lissiman E, Bhasale AL, Cohen M. (2014). Garlic for the common cold. Cochrane Database of Systematic Reviews, 2014(11), CD006206.
   This systematic review concluded that there was insufficient clinical trial evidence to determine whether garlic prevents or treats the common cold.
   Read the Cochrane review on PubMed
4. Ried K, Travica N, Sali A, et al. Garlic and cardiovascular health.
   Research into garlic and cardiovascular health has investigated potential effects on blood pressure and blood lipids. This evidence is particularly relevant when discussing concentrated garlic preparations and supplements rather than assuming the same effects from culinary quantities.
   Search the relevant research on PubMed
5. Bayan L, Koulivand PH, Gorji A. (2014). Garlic: a review of potential therapeutic effects. Avicenna Journal of Phytomedicine, 4(1), 1–14.
   A review of garlic’s biologically active compounds and the research surrounding its antimicrobial and other potential effects.
   Read the research on PubMed
6. Monash University FODMAP. High and low FODMAP foods.
   Garlic is naturally high in fructans, a type of FODMAP that can contribute to digestive symptoms in some people with IBS. Monash University is the research group behind the low-FODMAP diet and is a particularly useful resource for this aspect of the article.
   See the Monash FODMAP food guide
7. Monash University FODMAP. Cooking with onion and garlic – myths and facts.
   A practical resource explaining how fructans behave when garlic is used in cooking, including why garlic-infused oil can be useful for people following a low-FODMAP diet.
   Read the Monash University guidance
8. National Institutes of Health, Office of Dietary Supplements. Vitamin B12 Fact Sheet for Consumers.
   Useful for clarifying that vitamin B12 is not naturally present in garlic and is primarily found naturally in animal-derived foods, with some plant-based foods fortified with B12.
   Read the NIH vitamin B12 fact sheet