Garlic for Dogs: A Complete Guide

Can dogs eat garlic?

Yes, despite what you may have heard, dogs can safely eat garlic says our in-house dog nutritionist. Dogs have been benefiting from garlic since Roman times.

Health benefits of garlic for dogs

• Immune support: garlic acts as a mild, natural antibiotic, antifungal and antiviral agent.
• Cardiovascular health: garlic serves as a vasodilator to widen blood vessels, improve circulation and help prevent blood clots.
• Antioxidant properties: garlic contains flavonoids that neutralise free radicals and boost natural cellular defences.
• Gut health: garlic contains inulin, a prebiotic fibre that helps detoxify the gut and support beneficial bacteria.
• Oral health: evidence suggests that aged garlic extract can reduce gum inflammation and bad breath associated with gingivitis.
• Pest deterrent: garlic can make your dog less appealing to fleas and ticks by altering their skin scent.

Where it all went wrong for dogs and garlic

The 2000 study of garlic on dogs published in the American Journal of Veterinary Research, concluded that garlic can cause oxidative damage to a dog’s red blood cells, leading to the recommendation that garlic should not be fed to dogs.

However, this study is highly debated in veterinary medicine because the researchers administered exceptionally high, unrealistic doses — the equivalent of feeding roughly 20 to 25 raw garlic cloves a day to an average-sized dog.

Four dogs were given 5 grams of whole garlic extract per kilogram of body weight daily via a feeding tube for 7 consecutive days, while four control dogs received water. The dogs given garlic showed a significant drop in red blood cell counts and haemoglobin. They developed Heinz body anaemia and eccentrocytes — microscopic markers indicating that the cell membranes had oxidised and become fragile. Despite the clear cellular damage, none of the dogs actually developed clinical haemolytic anaemia during the study.

Why the findings are debated
The study established the scientific baseline for garlic toxicity in dogs, but it used extreme amounts. For perspective, a 10kg (22lb) dog would need to eat about 50 grams of raw garlic daily to match the study’s dosage.

Modern veterinary toxicology consensus generally states that garlic toxicity typically occurs when a dog eats 15 to 30 grams of garlic per kilogram of body weight. A single average grocery clove weighs only 3 to 7 grams.

A newer study published in Frontiers in Veterinary Science (2018) tested lower, realistic doses of aged garlic extract (90 mg/kg) over 12 weeks. It found no adverse health effects and noted that the low dose actually increased beneficial antioxidant activity in the dogs.

That said, certain Japanese dog breeds (such as Akitas, Shiba Inus and Jindos) possess a genetic trait resulting in unique red blood cell structures. They are far more sensitive to the oxidising compounds in the allium family and should never be given garlic.

Garlic powder and garlic salt are highly concentrated and pose the fastest risk of severe poisoning.

Other dog-safe vegetables

• Broccoli. Nutrient-dense canine superfood.
• Sweet potatoes
• Carrots
• Green beans. Low calorie, high fibre, vitamin rich.
• Leafy greens
• Parsnips
• Celery
• Beetroot

See the full range of dog-safe vegetables here.