If eucalyptol sounds familiar, it’s because you’re probably thinking of eucalyptus, and for good reason — eucalyptol is a terpenoid found in the famous tree it’s named after. Perhaps it’s precisely the mystique surrounding the coveted eucalyptus tree that is the reason behind the scientific research on eucalyptol, which has demonstrated serious therapeutic promise.
Eucalyptol is also known as 1.8-cineole, and besides eucalyptus, the terpenoid alcohol is also found in rosemary, sweet basil, sage, mint, tea tree, bay leaves, and last but not least, certain cannabis cultivars such as Critical Mass and Lemon Wheel. 
When applied to human colon cancer cells (in vivo), eucalyptol induced apoptosis, which is a form of programmed cell death that removes cells that have run their course and can potentially turn cancerous.  This process is essential to proper functioning and maintaining the overall balance in our bodies.
By promoting apoptosis, eucalyptol inhibited colon cancer cell growth, prompting researchers to believe that the terpene “would be an effective strategy to treat colorectal cancer.” 
Cognitive Improvement and Neuroprotection
When rosemary oil, of which eucalyptol is a major constituent, was dispersed into a room while a study’s participants were performing mathematical tasks, the speed and accuracy of their answers improved. A positive correlation was established between higher blood levels of eucalyptol and correct answers. 
But eucalyptol’s cognitive benefits may potentially have implications on a much grander scale — Alzheimer’s disease. This condition is associated with an accumulation of beta-amyloid plaque proteins in the brain, which hinders cell-to-cell signaling at synapses and leads to inflammation. And inflammation is one of the main plights of the brain, as it generates oxidative stress and neurodegeneration.
However, eucalyptol alleviated the inflammation caused by beta-amyloid plaque proteins, albeit in petri dish models. 
Anti-Inflammatory and Antioxidant
Speaking of protecting against inflammation and oxidative stress, eucalyptol has showcased potential in separate studies on these conditions.
The terpenoid’s anti-inflammatory effects have mainly been explored in the context of respiratory problems, including cigarette smoke irritation, asthma, bronchitis, pneumonia, and more, displaying significant efficacy. 
Eucalyptol’s antioxidant properties have been investigated for different medicinal purposes, which only goes to show how sweeping the terpenoid’s benefits might be. In a study from 2011, eucalyptol, along with myrcene, “showed antioxidant activity and eliminated TCDD-induced oxidative stress in rats in a time-dependent manner.”  TCDD is a toxic environmental pollutant.
Eucalyptol is yet another terpenoid to be excited about.
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