The sense and nonsense about garlic.

Garlic is natural and effective. Allicin from garlic is a natural ingredient in animal care. But on the internet, the selective story "toxic" is copied verbatim without any nuance.

"Garlic has excellent properties, but the same rule applies here as for all herbs: more is not better". (Source: Mary L. Wulff-Tilford on garlic - Herbs for Pets)

Almost anything can be "toxic" or become toxic in excessive amounts. Just like water, garlic can also be toxic. It therefore depends entirely on the amount, the form (fresh, powder, extract), the duration of exposure, and the sensitivity of the animal (cats are more sensitive than dogs). Ultimately, everything has a toxic dose.

Scientific sources (such as the Merck Veterinary Manual, ASPCA, Pet Poison Helpline, and various studies) confirm that garlic (Allium sativum) can be dose-dependently toxic due to sulfur compounds (such as thiosulfates and allicin) that cause oxidative damage to red blood cells (Heinz bodies, hemolytic anemia). But with normal, small amounts in food or supplements, we rarely see problems, and real clinical poisonings are often linked to extremely high doses or concentrated forms.

Toxicity in practice: when does it really become dangerous?

Dogs:

• Toxic doses often start around 15-30 g of fresh garlic per kg of body weight (or lower for powder/extract, because it is more concentrated). Example: A 20 kg dog would need 300-600 g of fresh garlic (that's 60-120 cloves!) for serious risks of anemia – something that almost never occurs in practice.
• Studies (such as the well-known Hokkaido study from 2000) show changes in blood cells at ~5 g/kg per day (approx. 100 g for a 20 kg dog, or ~20 cloves daily), but no acute anemia or visible symptoms.
• Many Dutch animal clinics and holistic sources state: toxic from 16-24 g per day absolutely, or 1 clove per 20-25 kg as a safe guideline.
• Small amounts (½-2 cloves per day, depending on size) are considered safe by many experts for therapeutic use.

Cats:

• Much more sensitive (3-5x more sensitive than dogs).
• Toxicity from ~5 g/kg (or less for concentrated), so for a 4-5 kg cat: it can become problematic at 20-25 g (4-5 cloves). An amount that any cat gets?.

Experience and research.

As a company, we have been using dried, aged white garlic (Allium sativum) from Spain for many years. Interestingly, a specific study from 2018 in BMC Veterinary Research showed that Aged Garlic Extract (pressed garlic that has been aged for months) caused no damage to blood cells in dogs over 12 weeks. This is because the aging process largely breaks down the toxic organosulfides.

Choosing black-and-white advice

Veterinarians and veterinary organizations regularly state that "garlic is toxic" for dogs and cats. This is because it is a simplified, cautious message to minimize risks, despite the fact that toxicity is dose-dependent. The lower limit of 5 grams* of Allium plant material per kg of body weight, as stated by the NVIC (National Poisons Information Centre) in collaboration with the University Clinic for Companion Animals of the University of Utrecht, serves as a conservative guideline for possible oxidative damage to red blood cells (due to thiosulfates). This is based on veterinary toxicology and annual reports on acute poisonings in animals, where the NVIC registers thousands of reports annually (e.g., in 2024: 8,701 animals, mainly dogs and cats).

In practice, however, veterinarians often choose black-and-white advice and therefore state "garlic is toxic" in advance to prevent any accidents. This is copied verbatim on the internet without the necessary nuance. Real poisonings are therefore quite rare because it depends entirely on the amount, the form (fresh, powder, extract), the duration of exposure, and the sensitivity of the animal (cats are more sensitive than dogs).

*Example: If we assume the lower limit of 5 grams of Allium plant material per kg of body weight, as indicated by the UMC Utrecht NVIC department, then a 5 kg cat would have to eat 1,000 BF® garlic tablets (in 1 sitting) and a 20 kg dog would have to eat 7.5 boxes of BF® garlic bonbons in 1 sitting to even reach the lower limit. There is no dog or cat that consumes this amount. 

General health and hereditary predisposition

The use of garlic in the diet or as a supplement for health benefits can help maintain the general health of healthy dogs and cats. Of course, any animal with existing anemia and/or a hereditary predisposition should not receive garlic. If a dog or cat already has abnormal blood values (anemia, leukemia, other blood diseases, or recent chemotherapy), it is strongly advised not to give garlic products. Asian dog breeds such as the Akita and the Shiba Inu have a hereditary variation in their red blood cells, making it wise not to give garlic. Puppies younger than 8 weeks should also not receive garlic, because they only start producing new blood cells after 6-8 weeks. However, kittens produce new blood cells continuously from the fetal stage, and this process never stops as long as the animal is healthy. Nevertheless, just like with puppies, we maintain the feeding advice "from 20 weeks" for kittens.

Summary

A dog or cat has to consume quite a lot of garlic for it to really be toxic. Real poisonings are therefore rare, but when they do occur (e.g., through human food), they lead to symptoms such as vomiting, diarrhea, pale gums, and anemia – hence the categorical warning where veterinarians want to prevent owners from experimenting and accidentally crossing the line. However, one does not need to experiment. BF®Petfood has had safe and healthy products with garlic on the market for many years, including the original garlic bonbons and tablets. These support the natural barrier of the skin and coat and the general health of your dog and/or cat.

ATTENTION! Due to EU legislation, we are not allowed to state what our garlic products are intended for and what effects they have. "All herbs have been put on hold by the EFSA. This means that no claims will be granted in the 'Register of nutrition and health claims' in the coming years. Only registered veterinary medicines may state an indication. These are generally often products from multinationals with chemical substances. Something we as a Frisian pet food company with natural and organic products will never choose. For more information about herbal supplements, you can visit the website of IVG 

For more information, email: info@bfpetfood.nl or use the contact page.