However, persistent low-grade inflammation may contribute to the development or progression of several chronic conditions, including cardiovascular disease, metabolic disorders, and certain inflammatory diseases.
Garlic contains compounds that have demonstrated anti-inflammatory activity in laboratory investigations.
Allicin, S-allyl cysteine, diallyl disulfide, and other organosulfur substances have been studied for their ability to influence inflammatory signaling pathways.
Some experimental studies suggest that garlic-derived compounds may affect the activity of nuclear factor kappa B (NF-κB), a signaling pathway involved in the regulation of inflammatory responses.
Researchers have also investigated changes in inflammatory biomarkers, including C-reactive protein and tumor necrosis factor-alpha.
The 2025 meta-analysis published in Nutrition Reviews reported reductions in certain inflammatory markers among participants receiving garlic supplementation.
Nevertheless, these findings should be interpreted cautiously.
Inflammation is a complex process, and changes in individual biomarkers do not necessarily translate into the prevention or treatment of inflammatory diseases.
A healthy dietary pattern, regular physical activity, adequate sleep, and appropriate medical care remain important components of long-term inflammation management.
Garlic may contribute beneficial phytochemicals to the diet, but it should not be viewed as a standalone anti-inflammatory treatment.
8. Antibacterial Properties of Garlic
Garlic has long been recognized for its pungent odor and traditional use in food preservation and home remedies.
Modern laboratory research has identified several sulfur-containing compounds with antibacterial activity.
Allicin is particularly interesting because it can react with thiol-containing proteins and enzymes in microorganisms, potentially interfering with essential cellular functions.
This chemical reactivity may help explain why allicin has demonstrated activity against several bacterial species in laboratory experiments.
One frequently cited study by Lu and colleagues, published in the Journal of Antimicrobial Chemotherapy in 2012, investigated diallyl sulfide against Campylobacter jejuni.
The researchers found that the compound could disrupt bacterial biofilms and eliminate bacterial cells under experimental conditions.
The study generated interest because bacterial biofilms can make microorganisms more difficult to eliminate through conventional antimicrobial treatments.
However, the findings must not be interpreted as evidence that eating raw garlic can cure bacterial infections.
The laboratory concentrations, delivery methods, exposure conditions, and biological environment are very different from those encountered after consuming garlic as food.
Furthermore, garlic compounds may be absorbed, transformed, and metabolized before reaching potential sites of infection.
Garlic is therefore best understood as a food containing potentially useful antimicrobial phytochemicals rather than an alternative to medically prescribed antibiotics.
9. Garlic and Fungal Infections
Garlic has also been investigated for its potential antifungal properties.
One of the microorganisms frequently studied in this context is Candida albicans, a yeast that can normally exist in small quantities in the human body but may cause infections under certain circumstances.
Laboratory experiments have shown that allicin and other garlic-derived compounds can inhibit the growth of certain fungal organisms.
The proposed mechanisms include disruption of cellular metabolism, interference with enzyme activity, and damage to essential structures involved in fungal survival.
Some studies have also investigated garlic extracts against other fungi responsible for superficial infections.
Although these findings are scientifically interesting, evidence from laboratory experiments does not establish that consuming garlic can treat fungal infections in humans.
The concentration of active substances, their stability, and their ability to reach infected tissues are important limitations.
Furthermore, applying raw crushed garlic directly to the skin can cause significant irritation and chemical burns.
People with suspected fungal infections should seek appropriate medical advice and use treatments that have been clinically evaluated for the relevant infection.
10. Garlic, Liver Function, and Metabolic Health
The liver is one of the body's most important metabolic organs.
It participates in the processing of nutrients, regulation of blood glucose, production of bile, metabolism of medications, and removal of various waste products.
Because the liver is continuously exposed to substances absorbed from the digestive tract, it also plays an important role in protecting the body from potentially harmful compounds.
Oxidative stress and chronic inflammation are involved in several forms of liver disease.
Garlic has attracted scientific attention because its antioxidant and anti-inflammatory compounds may influence some of these processes.
10.1. Garlic and Metabolic Dysfunction-Associated Steatotic Liver Disease
Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as nonalcoholic fatty liver disease (NAFLD), is characterized by excessive fat accumulation in the liver in association with metabolic risk factors.
It is frequently associated with obesity, insulin resistance, type 2 diabetes, and abnormal blood lipid levels.
A randomized clinical trial published in 2020 investigated the effects of garlic powder supplementation in adults with fatty liver disease.
The study initially included 110 participants, with 98 completing the intervention. Participants received either garlic powder or a placebo over approximately 15 weeks.
The researchers reported improvements in liver fat measurements and several metabolic indicators in the garlic group compared with the placebo group.
The results were encouraging, but the study was relatively small and had a limited follow-up period (Soleimani et al., 2020).
A subsequent systematic review and meta-analysis also reported favorable changes in certain liver enzymes and metabolic measurements among people receiving garlic supplementation.
However, the authors emphasized that additional high-quality clinical trials are needed to confirm these findings.
Garlic should not be considered a proven treatment for MASLD or other chronic liver diseases.
The established approach to managing metabolic liver disease focuses on addressing underlying metabolic risk factors, improving dietary quality, maintaining appropriate physical activity, and obtaining medical assessment when necessary.
10.2. Garlic and Oxidative Stress in the Liver
Researchers have also investigated whether garlic-derived antioxidants can influence oxidative damage in liver tissue.
Animal studies suggest that certain garlic compounds may affect antioxidant enzyme activity and inflammatory signaling.
These findings have generated interest in the possibility that garlic could support normal liver function.
Nevertheless, animal experiments cannot establish clinical effectiveness in humans.
There is also no reliable evidence that consuming large amounts of garlic can reverse liver damage caused by alcohol, medications, infections, or other medical conditions.
Concentrated supplements may themselves interact with medications, making professional guidance particularly important for people with existing liver disease.
11. Potential Neuroprotective Effects of Garlic
The brain is highly metabolically active and requires a continuous supply of oxygen and nutrients.
Because of its high energy requirements, brain tissue is particularly sensitive to disturbances in blood flow and oxidative balance.
Oxidative stress and inflammation have been investigated in relation to several neurological conditions, including age-related cognitive decline and neurodegenerative diseases.
Garlic contains sulfur-containing compounds and antioxidants that have attracted interest for their possible neuroprotective properties.
Some laboratory and animal studies suggest that aged garlic extract and S-allyl cysteine may influence oxidative stress and inflammatory processes in nervous tissue.
Researchers have also examined whether garlic-derived compounds may affect signaling pathways involved in neuronal survival.
11.1. Memory and Cognitive Function
Certain animal experiments have reported improvements in learning and memory-related measurements following garlic supplementation.
