How long does it take for garlic to work in your body?

October 27, 2025 •

4 min read

According to a 2016 review, the immune-boosting effects from aged garlic extract (AGE) can start to appear after about 45 days of consistent consumption. Understanding how long does it take for garlic to work in your body depends heavily on the specific compounds, preparation method, and the health goal you are targeting.

Quick Summary

The timeline for garlic's effects varies based on the type of compound and preparation, with some volatile compounds being absorbed quickly while others require weeks or months of consistent intake for therapeutic benefits. The active substances, like allicin, are metabolized rapidly into other bioavailable compounds, making consistency crucial for observing long-term health improvements.

Key Points

Immediate Effects: Volatile sulfur compounds from crushed raw garlic are absorbed within hours and are responsible for the characteristic odor and some immediate, transient effects like an increase in nitric oxide.
Long-Term Benefits: Significant therapeutic benefits, such as improvements in cholesterol or blood pressure, typically require consistent daily intake for a minimum of 8 to 12 weeks to see noticeable results.
Allicin vs. Metabolites: Allicin, the unstable compound formed when garlic is crushed, is not typically found in the bloodstream. Instead, it is rapidly metabolized into other bioavailable compounds that then exert systemic effects.
Aged Garlic Extract: Supplements like aged garlic extract (AGE) contain more stable, water-soluble compounds like S-allylcysteine (SAC), which have better absorption and are responsible for many of the studied long-term cardiovascular benefits.
Preparation is Key: To maximize the potency of raw garlic, crush or chop it and let it stand for 10–15 minutes before use. This allows allicin to form before heat from cooking can destroy the enzyme responsible for its creation.
Individual Variability: The rate and extent to which garlic's active compounds are absorbed and metabolized can vary greatly from person to person, impacting the observed effects.

The complex chemistry behind garlic’s health benefits

Garlic's potency comes from a complex biochemical reaction that occurs when it is crushed, chopped, or chewed. The enzyme alliinase, stored in one part of the garlic clove, mixes with the compound alliin, stored separately. This reaction rapidly produces allicin, the sulfur-containing compound responsible for garlic’s distinctive odor and many of its initial health effects. However, allicin is highly unstable and breaks down almost immediately into other compounds. This means that the effects you feel from eating garlic are not from allicin alone, but from a cascade of rapidly created and metabolized compounds.

Short-term effects: What happens in hours?

The most immediate effects of garlic are often related to its pungent, volatile compounds that are quickly absorbed and exhaled. Studies have shown that garlic metabolites, such as allyl methyl sulfide (AMS), can be detected in the breath within hours of consumption. Some studies have also observed an increase in nitric oxide plasma concentrations within two to four hours after consuming fresh garlic, which can positively impact vascular function. However, these are transient effects. The deeper, more therapeutic benefits linked to conditions like cholesterol and blood pressure take much longer to manifest.

Medium-to-long-term effects: The power of consistency

The therapeutic benefits associated with garlic often require consistent, long-term intake. The key lies in compounds like S-allylcysteine (SAC), which is a more stable, water-soluble compound found in aged garlic extract (AGE). Unlike the volatile compounds, SAC is absorbed efficiently and stays in the body longer. This longevity allows for a more sustained effect that builds up over time. Clinical studies on cardiovascular health, cholesterol reduction, and immune function have shown noticeable results only after several weeks or months of daily use. For example, studies on blood pressure and cholesterol often last for at least eight weeks or several months.

The crucial role of preparation method

The way garlic is prepared is arguably the most important factor in determining how quickly and effectively it works. The enzymatic reaction that produces allicin is easily disrupted by heat. If you cook garlic immediately after chopping, you lose a significant portion of its allicin potential. Letting crushed garlic sit for 10–15 minutes before cooking allows the allicin to form and then transform into other beneficial compounds, increasing the overall bioavailability. In contrast, aged garlic extracts (AGE) are processed in a way that creates stable, water-soluble compounds like SAC, offering consistent, long-term benefits that are less dependent on immediate enzymatic action.

How different garlic forms affect absorption and benefits


Garlic Form	Active Compounds	Preparation	Onset of Benefits	Ideal Use Case
Raw, Crushed Garlic	Allicin (short-lived), Diallyl Disulfide (DADS)	Crushed and left for 10-15 minutes before consumption.	Short-term effects within hours, longer-term effects with consistent daily use.	A quick immune boost, or for enhancing flavor with potential long-term benefits if consumed consistently.
Cooked Garlic	Fewer allicin-derived compounds, lower potency overall.	Heated shortly after chopping or whole.	Limited therapeutic effect, primarily for flavor.	Culinary purposes, when health benefits are not the primary focus.
Aged Garlic Extract (AGE)	S-allylcysteine (SAC) and other stable, water-soluble compounds.	Processed and aged into a concentrated supplement.	Medium to long term (weeks to months), requires consistent daily intake.	Targeting chronic health conditions like hypertension or hyperlipidemia.
Garlic Oil	Diallyl sulfides (DAS, DADS) and dithiins.	Processed into an oil-based supplement.	Inconsistent effects reported, depends on processing.	Some clinical trials suggest benefits, but bioavailability is often poor or variable.

Conclusion: Patience and consistency are key

In conclusion, if you are looking for immediate results, such as a mild immune or vascular response, you might notice some effects from raw, crushed garlic within a few hours. However, the most significant and well-documented therapeutic effects of garlic, such as improvements in cholesterol levels, blood pressure, and long-term immune function, require consistent daily intake over several weeks or months. The preparation method is critical; leaving crushed garlic to rest for 10-15 minutes before cooking can maximize potency, but for guaranteed consistency and bioavailability, supplements like Aged Garlic Extract (AGE) are often used in clinical studies. Ultimately, there is no magic bullet—incorporating garlic into your routine as a dietary staple is the most effective approach to reaping its long-term health rewards.

The bioavailability of garlic compounds varies based on preparation

The absorption of garlic’s beneficial compounds varies, affecting the onset of different health benefits. For instance, some volatile compounds can appear in the breath within hours, while stable, water-soluble compounds require weeks or months to build up and exert therapeutic effects on the body.

Long-term consistency is more important than quick fixes

Most clinically relevant benefits, such as cardiovascular improvements and cholesterol reduction, are observed after months of consistent, daily garlic consumption, rather than from a single dose.

The type of garlic product matters

Different garlic products, like raw garlic, cooked garlic, and supplements, contain varying levels of active compounds due to different processing methods. Aged garlic extract (AGE) is standardized for stable compounds like SAC, while raw garlic’s allicin is less stable.

Individual differences influence garlic's effects

Individual physiology and metabolism play a significant role in how the body processes and reacts to garlic compounds. The concentration and timing of garlic metabolites in urine can vary widely between individuals.

High doses require medical consultation

While garlic is generally safe, very high doses or certain supplements can have side effects and interact with medications, especially blood thinners. It is important to consult a healthcare provider before significantly increasing garlic intake or starting supplements.

Frequently Asked Questions

Raw, crushed garlic can release volatile compounds that are absorbed faster, potentially offering some immediate, transient effects like a boost in nitric oxide. However, for significant, long-term health benefits, cooked garlic (if prepared properly) and raw garlic both require consistent, daily consumption over weeks or months.

Allicin is a highly unstable and transient compound that forms when garlic is crushed. Upon ingestion, it is rapidly broken down and metabolized into other more stable, fat-soluble and water-soluble organosulfur compounds. These metabolites, not allicin itself, are then absorbed into the bloodstream and exert systemic effects.

Clinical studies have shown that it can take at least 8 weeks of consistent, daily intake of garlic or garlic supplements to observe a modest reduction in total and LDL cholesterol levels. For optimal results, longer durations of use (e.g., 2–3 months) are often recommended.

Both fresh garlic and supplements have benefits. Fresh garlic, when crushed and left to sit, produces allicin, which is then metabolized. Aged garlic extract (AGE) supplements are standardized for more stable, bioavailable compounds like S-allylcysteine (SAC), which have been shown to be effective in clinical trials over a long term. The best choice depends on your health goals and preference for consistency.

Garlic's compounds are metabolized and eliminated at different rates. Water-soluble compounds typically flush out within 24–48 hours, while fat-soluble ones can remain in the body for multiple weeks and can build up in fatty tissues.

While consuming garlic occasionally is part of a healthy diet, the most significant and scientifically backed therapeutic benefits, particularly for chronic conditions like hypertension and hyperlipidemia, come from consistent, daily intake over a prolonged period. Occasional consumption offers minimal, short-lived effects.

Yes, it is recommended to wait at least 10–15 minutes after crushing or chopping garlic before heating or cooking it. This allows the enzyme alliinase to convert alliin into allicin, the precursor to many of the beneficial compounds, maximizing its potency.