Several garlic bulbs on a cloth on a table

The health benefits of garlic

A tasty superfood or smelly spice? Get the full story on this common ingredient from nutrition expert Jo Lewin.

An introduction to garlic

Highly valued throughout the ages as a culinary spice, garlic is one of the oldest cultivated plants in the world. It is a hardy perennial belonging to the liliaceae family. Other members of this family include leeks, chives, spring onions and shallots, all distinguished by their pungent aroma and flavour.


Garlic’s usage predates written history; Sanskrit records document the use of garlic remedies approximately 5000 years ago. Legend suggests that Egyptian pharaohs prized garlic very highly, and slaves building the pyramids were given a daily ration to keep them fit and strong. Throughout history, garlic has been regarded as a well-trusted remedy, especially during epidemics such as cholera and tuberculosis and in World War I, where it was used as an antiseptic applied to wounds to cleanse and heal and to treat dysentery caused by the poor sanitary conditions in the trenches.

Nutritional highlights

The garlic bulb is the most commonly used portion of the plant, composed of eight to 20 individual teardrop-shaped cloves enclosed in a white parchment-like skin. It is an excellent source of vitamin B6 (pyridoxine). It is also a very good source of manganese, selenium and vitamin C. In addition, garlic is a good source of other minerals, including phosphorous, calcium, potassium, iron and copper.

A 100g serving provides:

  • 98 calories
  • 7.9g protein
  • 0.6g fat
  • 16.3g carbohydrates
  • 5.5g fibre

Tip: If you love eating raw garlic but hate the lingering aftertaste, try chewing parsley – it works very well as a breath freshener.

Many of the perceived therapeutic effects of garlic are thought to be due to its active ingredient allicin. This sulphur-containing compound gives garlic its distinctive pungent smell and taste. Luckily for us foodies, the action of chopping or crushing garlic supposedly stimulates the production of allicin; however, it is thought that cooking garlic inhibits the formation of some of the perceived medicinal properties.

Garlic chopped on a chopping board


Modern research has focused on garlic’s potential to reduce the risk of heart disease, cholesterol levels and cancer. Several studies suggest that garlic makes platelets (the cells involved in blood clotting) less likely to clump together and stick to artery walls, therefore acting as an anticoagulant and reducing the risk of heart attacks. The sulphurous compounds have also been studied for their ability to inhibit cancerous cells and block tumours by slowing DNA replication. The ability of these compounds to depress tumour cell proliferation is still being studied extensively.

Garlic may also lower blood pressure slightly, mainly through its ability to widen blood vessels.

Garlic has a long history of use as an infection fighter against viruses, bacteria and fungi. It has been referred to as ‘Russian penicillin’ to denote its antibacterial properties. Some skin conditions, such as warts and insect bites, may respond to garlic oil or a crushed raw garlic clove.

How to select and store

For the best flavour and maximum health benefits, buy fresh garlic. Do not buy garlic that is soft, shows evidence of decay or is beginning to sprout. Garlic in flake, powder or paste form is convenient, but it is not as good as fresh garlic. It is best stored at room temperature in an uncovered container in a cool, dark place away from exposure to heat and sunlight. Storing it in this manner will help prevent sprouting. Depending on its age and variety, a whole garlic bulb will keep for anywhere from two weeks to two months.

Tip: Once you break the head of garlic, it greatly reduces its shelf life to just a few days.


Garlic poses little safety issues and allergies are rare. If you are using the herb for cholesterol, have your levels checked after three months. The recommended daily amount of garlic ranges from half to one whole clove per day (around 3000-6000mcg of allicin). Please note that some people may experience indigestion, intestinal gas and diarrhoea when taking high doses of garlic.

Recipe suggestions

A simple aïoli is a great accompaniment for roasts, fish or as a dip:
Homemade aïoli
Salmon & prawns with dill & lime aïoli

Make your own delicious cheesy garlic bread:
Garlic & basil ciabatta
Quick tomato soup with cheesy garlic dippers

Garlic works well with mushrooms:
Garlic mushroom burgers
Mushrooms on toast
Garlicky mushroom penne

Pair garlic with prawns:
Stir-fry prawns with peppers & spinach
Lemony prawn bruschettas

It adds flavour to mashed potato and veggie stews:
Roast sweet potato squash & garlic mash
Garlic mash potato bake
Spicy root & lentil casserole

Garlic is great with chicken:
Garlic chicken with herbed potatoes

Want more? Take inspiration from our healthy garlic recipes.

This article was last reviewed on 23 September 2019 by Kerry Torrens.

Kerry Torrens BSc. (Hons) PgCert MBANT is a Registered Nutritionist with a post graduate diploma in Personalised Nutrition & Nutritional Therapy. She is a member of the British Association for Nutrition and Lifestyle Medicine (BANT) and a member of the Guild of Food Writers. Over the last 15 years she has been a contributing author to a number of nutritional and cookery publications including BBC Good Food.

Jo Lewin is a registered nutritionist (RNutr) with the Association for Nutrition with a specialism in public health. Follow her on Twitter @nutri_jo.


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