Is raw garlic safe to eat? (3+ risks)
In this article, we will discuss whether it is safe to eat raw garlic, what are the risks and benefits of eating raw garlic, when raw garlic is not safe to eat, and how to improve the safety of eating raw garlic.
The benefits of garlic as an antimicrobial and antioxidant agent have been known for ages and for this reason and due to its flavour, garlic is widely used as a seasoning and a remedy in many parts of the world.
Is raw garlic safe to eat?
Yes, garlic is safe to eat, unless it is spoiled. Garlic can be consumed raw or cooked, dried or in the form of a powder or extract. There are many products derived from garlic with different benefits, as processing alters the chemical composition of garlic (1, 2).
Garlic has antimicrobial activities and is used as a natural food preservative, however, garlic is not free from microbial attack, especially by fungi, which can cause deterioration of the plant (4, 5). In this way, garlic is not always safe to eat.
What are the risks of eating raw garlic?
The risks of eating raw garlic are summarised in the table below (3, 4, 5, 6):
|Garlic can be contaminated with several species of fungi, including Penicillium, Botrytis and Fusarium. In addition, garlic can be contaminated with pathogenic bacteria by cross-contamination and poor handling. The ingestion of contaminated garlic can lead to foodborne diseases.||Vomiting, diarrhoea, nausea, fever, and stomach pain. In severe cases can lead to dehydration and hospitalisation.|
|Poisoning from fungal toxin||Poisoning by the ingestion of toxins produced by fungi that grow in the raw garlic||Fungal toxins, or mycotoxins have carcinogenic and mutagenic effects and may cause vomiting, nausea, respiratory infections and infections in other organs, damage to kidneys, and immunosuppression.|
|Poisoning from botulinic toxin||Poisoning by the botulinic toxin is possible when garlic is stored under anaerobic conditions or in an environment of low oxygen concentration. It is common when raw garlic is stored in oil without being previously acidified (7).||Botulism or poisoning by the botulinic toxin can lead to vomiting, constipation or diarrhoea, difficulty in speech, swallowing and breathing, and paralysis of arms and legs. In severe cases can lead to death.|
|Allergies by the ingestion of skin contact with garlic by allergic or sensitive individuals||Skin allergies manifest by urticaria, skin burn and dermatitis. Allergy from ingestion may result in diarrhoea, dyspepsia, bronchitis, asthma and anaphylaxis (8).|
What are other possible drawbacks of raw garlic?
Other possible drawbacks of eating raw garlic are gastrointestinal symptoms, such as bloating, upset stomach, and flatulence, especially when eaten on an empty stomach.
In addition, it is possible to have bad breath and bad skin odour due to the ingestion of raw garlic when ingested in large amounts (6).
Individuals taking medication with anticoagulant effects should eat garlic in moderation and pregnant women should ask for medical assistance before eating raw garlic.
What are the benefits of eating raw garlic?
The benefits of eating raw garlic are the health benefits of garlic, which are improved when garlic is consumed raw. Garlic has improved antioxidant properties due to its high concentration of sulphurous compounds and phenolics (1, 2).
A 7-year-long study reported that the ingestion of raw garlic at least twice a week reduced the risks of liver cancer in the population when compared to the low ingestion of garlic (2).
Also, garlic has an anti-aggregatory effect on platelets in the blood, thus reducing the risks of cardiovascular diseases related to platelet aggregation.
While raw and slightly boiled garlic has high activity against aggregation, long-boiling eliminated this property from the garlic (1).
When is raw garlic not safe to eat?
Raw garlic is not safe when it is spoiled or when stored with oil without acidification (3, 4, 6, 7). Cross-contamination of raw garlic can occur by improper handling of other foods, which results in unsafe raw garlic.
Fungal contamination: Common spoilage in garlic is fungal contamination. Several fungi species grow in garlic, such as Penicillium, Aspergillus, Botrytis and Fusarium, which produce toxins that lead to negative effects on health.
Fungal growth can be noticed by the formation of coloured spores, such as black, green, blue and rot discolourations, changes in texture, such as softening and rot, and generation of off-odours (5).
Growth of Clostridium botulinum: Cl. botulinum is a spore-forming bacteria that produces the botulinic toxin which may be fatal when ingested. When garlic is stored in low-oxygen conditions, the bacteria may develop (4, 7).
Aromatised oil with garlic cloves which were not previously acidified is a possible medium for the development of Cl. botulinum (7).
How to improve the safety of eating raw garlic?
To improve the safety of eating raw garlic, you should store garlic in a dry and ventilated place, protected from heat and sunlight (4, 5). Improper storage can lead to fungal growth and the generation of mycotoxins.
To prepare aromatised oil with garlic and herbs, it is necessary to acidify the oil with citric acid and keep the oil refrigerated (7). This can prevent the development of Clostridium botulinum.
To acidify garlic and herbs, you should soak the 1 part of peeled raw garlic into 3 parts of a 3 % citric acid solution (in weight) for 24 hours. Then, use the acidified herbs in the oil infusions.
In this article, we discussed whether it is safe to eat raw garlic, the risks and benefits of eating raw garlic, when is raw garlic not safe to eat and how to improve the safety of eating raw garlic.
Raw garlic is a good option once in a while, however, I prefer eating cooked garlic, due to the strong flavour of raw garlic. Cooked garlic is also very nutritious and has many health benefits.
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