Health benefits of garlic

Why is garlic good for us?

Garlic is one of the most popular vegetables used in cooking around the world. It's known for its distinctive, strong aroma and flavour. With one small bulb consisting of around 10 cloves, garlic's nutritional value packs a punch as it contains vitamin C, vitamin B6, fibre and selenium.

Many of the claims made regarding the health benefits of garlic are linked to a compound called allicin. This sulfur-containing compound is activated when garlic is crushed or chopped and gives it its strong smell and taste.

As well as being eaten cooked or raw, garlic can be made into supplements that can be taken in the form of tablets, oils or capsules.

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We should all know that just as fruit and veg are good for us, so refined carbs, including sugar, are bad for us - there's basically no exception to this rule. But along with this well-evidenced mantra, there are other new "food rules" - and some of them seem to be more knee-jerk reaction than carefully considered guidance. Public Health England came under fire in 2017 for its campaign on acrylamide after the true (tiny) size of the risks it was warning against, became apparent. But the advice to reduce intake of red and processed meat combined to under 70 g a day resulted in no similar backlash. Here we look at the evidence and ask if there's more to this advice than 'meets' (no pun intended) the eye. new

Protects against colds and flu

Studies have suggested that garlic extract may help to boost your immune system, helping you to fight off common viral infections.

One study found that people who took aged garlic extract for three months during the cold and flu season experienced less severe symptoms and missed fewer days of school or work¹.

Aged garlic extract is created from garlic cloves that are sliced and soaked in an ethanol solution, before being left to age for up to 20 months.

Research also suggests that the compounds found in garlic may have antiviral properties, which helps to prevent viruses from entering our cells or replicating².

Lowers blood pressure

High blood pressure, or hypertension, is one of the main risk factors for heart attacks, heart disease and strokes. However, research has found that garlic - in the form of supplements - may have the ability to lower blood pressure and improve cardiovascular health.

A review of studies carried out in 2020 found that garlic extract lowered blood pressure and reduced stiffness in arteries - a problem linked to high blood pressure.

It was also found to improve the richness and diversity of 'good' bacteria in the gut, which helps to boost digestive health³. Studies have suggested that the allicin in garlic may help relax your blood vessels, allowing the blood to flow more easily⁴.

Lowers cholesterol

High cholesterol is when you have too much of a fatty substance called cholesterol in your blood and it can lead to heart problems and strokes.

Eating a healthy diet and exercising regularly - as well as avoiding smoking and not drinking too much alcohol - is important in keeping your cholesterol levels healthy.

But research suggests that garlic may also help to lower your levels of 'bad' cholesterol - the type that contributes to cardiovascular problems⁵.

Reduces arthritis pain

Arthritis is a common condition that causes pain and inflammation in the joints, but research has found that taking garlic supplements may help relieve soreness.

One study, involving 70 women, found that participants who took 1,000mg of garlic daily had reduced pain and tenderness. Although the study was small, the researchers suggested that garlic may have anti-inflammatory benefits⁶.

Another review of studies from 2018 found that participants who received garlic as a treatment had reduced pain and inflammation and improved physical function⁷.

The research into the benefits of garlic - both when eaten or taken in the form of a supplement - is promising. However, it's important to remember that garlic isn't a cure-all for health problems - and should be enjoyed as part of a healthy, varied diet.

Further reading

1. Percival: Aged garlic extract modifies human immunity.

2. Rouf et al: Antiviral potential of garlic (Allium sativum) and its organosulfur compounds: A systematic update of pre-clinical and clinical data.

3. Ried: Garlic lowers blood pressure in hypertensive subjects, improves arterial stiffness and gut microbiota: A review and meta-analysis.

4. Matsutomo: Potential benefits of garlic and other dietary supplements for the management of hypertension.

5. Khasawneh: Anti-hyperlipidemia of garlic by reducing the level of total cholesterol and low-density lipoprotein.

6. Moosavian: The effects of garlic (Allium sativum) supplementation on inflammatory biomarkers, fatigue, and clinical symptoms in patients with active rheumatoid arthritis: A randomised, double-blind, placebo-controlled trial.

7. Tavakoli-Far et al: Allium sativum L. (garlic) role in osteoarthritis: A systematic review of clinical trials.