Living in a wooded area means a lower risk of cancer. You can also benefit from this effect if you walk in the woods regularly. It is not just the calming factor that causes this. Trees contain volatile substances that you smell and inhale, and it turns out? These substances have a positive effect on our Natural Killer Cells. The scent of pine trees, white cedars, conifers, and camphor trees is therefore good for us. The essential oils that are absorbed through the mucous membranes by inhalation are also found in edible herbs such as rosemary, mint, thyme, basil, and sage.