No, essential oils do not get stronger over time; instead, they degrade.
While the question might imply a positive change in potency, the reality is that the chemical composition of essential oils changes over time, leading to a loss of quality and potential negative effects.
Understanding Essential Oil Degradation
Unlike fine wines or spirits that might improve with age, essential oils are volatile organic compounds that are susceptible to degradation.
Based on research and general understanding in aromatherapy:
- While essential oils do not expire in the traditional sense, they do degrade over time. This means their chemical structure changes from its original state.
This degradation is primarily caused by exposure to light, heat, and oxygen.
Effects of Degradation
Degraded essential oils are not just less effective; they can also pose risks. The degradation process leads to:
- Reduced effectiveness: The oil loses its original aroma profile and therapeutic properties (leading to reduced effectiveness). The beneficial compounds break down.
- Potential Risks: Degraded oils can form oxidation products which may cause skin irritation or allergic reactions (leading to reduced effectiveness and potential risks like skin irritation or allergic reactions).
Instead of becoming more potent or beneficial, they become weaker in their intended purpose and potentially harmful.
Factors Influencing Essential Oil Longevity
The rate at which an essential oil degrades depends heavily on how it is stored and the specific type of oil.
Key factors include:
- Light: UV rays accelerate degradation.
- Heat: High temperatures speed up chemical changes.
- Oxygen Exposure: Repeatedly opening bottles allows oxygen to enter, causing oxidation.
- Type of Oil: Citrus oils and those high in monoterpenes tend to degrade faster than resinous oils or woods.
Proper Storage for Essential Oils
To minimize degradation and preserve the quality and safety of your essential oils for as long as possible, proper storage is crucial:
- Use Dark Glass Bottles: Store oils in amber or cobalt blue glass bottles to protect them from light.
- Keep Lids Tight: Ensure bottle caps are tightly sealed to prevent oxidation from air exposure.
- Store in a Cool Place: Keep oils away from direct sunlight and heat sources. A cool, dark cupboard is ideal.
- Avoid Plastic: Essential oils can degrade plastic, and the plastic can contaminate the oil.
By taking these steps, you can help maintain the integrity of your essential oils for their intended shelf life, which varies by oil type but can range from 1-2 years for citrus oils to 5+ years for thicker oils like sandalwood or patchouli.
