Incense was a huge part of life in the ancient and medieval world. In medieval China, incense accompanied every aspect of life for intellectuals, officials, and the imperial family. They would wear incense in pouches on their belts, fan themselves with incense fans, dry their clothes over large incense burners, bathe in incense-infused water and wear incense-infused make up… not to mention have a lit incense burner in every room. Incense not only made life more pleasant through its fragrance, Traditional Chinese Medicine believes it has significant health benefits and helps with focus and relaxation. Today, we know from scientific research that the various ingredients of incense (such as sandalwood) have proven health benefits.

In recent years, incense has been making a “come back” into our daily lives for these reasons. Many people light an incense to accompany meditation, yoga, reading, or some quiet work time. Incense has also retained its use in religious and ancestral ceremonies all around the world, and you might often see them in large temples, shrines, as well as homes of friends who retain a small shrine.

After reviewing the academic research on this topic, our conclusion is that high quality natural incense, when used in moderation in a home setting, poses minimal health risks. We found a succinct and helpful summary posted on the Australian Government Cancer Council website about this precise question, so if you’re looking for a quick answer, we highly recommend it. We also wrote a fairly lengthy article on this specific topic, which includes links to a number of prominent academic studies in this area. If you’ve got the time, we also recommend that you check it out, and follow the links to read some of the studies yourself.

It is true that the burning of incense – like many other things we burn - releases chemicals into the air. These include Polycyclic aromatic hydrocarbons (PAHs), Volatile organic compounds (VOCs), particulate matter (PM), among others. But to date, no large scale studies have conclusively shown that moderate incense use at home releases the level of chemicals required to significantly affect a person’s risk of cancer. Our understanding is that all these chemicals exist in the air from many natural and industrial sources, and most of us live with some daily exposure to them in the form of car exhaust, dust from construction, factory emissions, natural fires, etc... Most governments regulate the level of these emissions, and set a level below which they are considered tolerable for general human health.

However, we do believe these chemicals are detrimental to health if they are inhaled at large quantities and for a pro-long period of time. This is especially the case if the incense has synthetic additives. So for temple workers or nearby residents, there can be significant health effects. We do not recommend anyone be exposed to incense on an ongoing basis in this way without protection.

That is not to say we shouldn’t all exercise moderation and take some common sense precautions when burning incense at home. We would suggest using high quality, natural incense as much as possible. And while the incense is burning, keep doors and/or a window open, ventilate the area regularly, and keep the incense some distance away from your face. You can also consider running an air purifier. We do all of these things when we use incense. Additionally, exercise caution to not start a fire, and take precautions to allow your pets to move around if you have any (see more details about pets in the section below).

There are no studies on the effect of incense smoke on dogs and cats, so we cannot conclusively say either way. What we believe is that whatever considerations we have for humans (the details of these are in our full article: Is Burning Incense Bad For You?) we also apply to our own fur babies, with a couple of distinctions. The first is that they are smaller and weigh less than humans, and the second is that they are much more sensitive to smell than us. Our educated guess is that this means a given amount of incense smoke would have a greater effect on our dogs and cats than on us. So there is a chance that what is perfectly tolerable for an average human is irritating for a small dog or cat.

We believe the sensible thing to do (and this is what we do) is to keep any lit incense some distance away from our pets. For example, I generally light my incense on the window seal, while my dog sits by my foot at my desk, so she is at least 6-8ft, or 2-3m away from the incense. I also keep the door to the room open, so the area has proper ventilation, and if she doesn’t like the incense I’m burning that day, she can freely go out of the room. The same applies to our cat. This arrangement has worked pretty well for our family, and most of the time our dog sits pretty contently by my side.

Incense has been used throughout history for spiritual and wellness purposes, and we believe that moderate use of incense has many benefits.Many traditional medicines, including Traditional Chinese Medicine, treated incense as an integral part of their preventative and healing systems, and today, we know from scientific research that the various ingredients of incense (such as sandalwood) have proven health benefits. Below are some ways that we believe incense help with our holistic wellbeing:

• Aids relaxation, reduces stress and alleviates anxiety
• Improves quality of sleep
• Increases focus, which can also improve creativity
• Many incense ingredients also have antiseptic and insect-repelling properties

With a more relaxed and focused state of mind, we believe that our immune system would likely be stronger, and we are less prone to a whole host of acute and chronic diseases. This is definitely the case from our personal experiences.

We believe burning a moderate amount of high quality incense in a home setting indoors is mostly safe. For a more detailed discussion of safety as it pertains to respiratory diseases, cancer and other negative health effects, please refer to the question above “Is incense bad for you? Is incense toxic?”

For the issue of safety as it pertains to potential fire hazards, we also believe the risk is minimal provided some basic precautions are taken. For example:

• Please ensure you put the incense on a surface that is heat-resistant, and no flammable items like curtains or books are near where the ashes can drop
• Please ensure that you do not leave the incense unattended
• Please place incense out of reach of children or pets
• Do not touch remnants of the incense right after it has finished burning. Also do not touch metal parts of the incense burner right after burning. Both of these may still be hot. Give them several minutes to cool down

While we believe that high quality natural incense, when used in moderation in a home setting, poses minimal health risks, we also believe that it is sensible to take some precautions and to keep the area for burning incense well ventilated (for more details, please refer to the question above “Is incense bad for you? Is incense toxic?”) We do sometimes open a window when we burn incense (but not so much that all of the incense smoke flows directly outwards, and we are left with no scent), but this is just one of the ways you can ventilate the area. Other alternatives including keeping the door to other rooms open, or using an air purifier. As long as you are taking some precautions to keep the air to the area flowing, you do not necessarily need to open a window.

While most sources on the internet would say good quality = 100% natural, we believe it should go beyond that. It is very simplistic to boil quality down to just this one thing – for example, if we randomly throw together a bunch of herbs and spices from the kitchen cabinet, and heat this mixture up with charcoal, would we consider this good quality incense? It’s certainly 100% natural.

All natural should absolutely be the foundations of a good quality incense, and you should check this carefully. However, there are other important elements to consider:

• The aroma of the incense – this is the most important element (although somewhat subjective), an incense cannot be considered good quality unless it has a smell you enjoy
• How quickly the aroma spreads and how long it lasts for
• Related to the above two elements, are the quality of each natural ingredient – for example, various grades of aloeswood (based on its oil content and formation location) can have a significant impact on the final aroma and its ability to penetrate and linger, and therefore the quality of the incense

It can be tricky to truly know the quality of an incense stick, as the judgement of smell also comes from experience. As you are still acquiring this experience and knowledge, there are a couple of simple signs you can check for:

• Whether it has a center stick, and what the stick is made of – if all other ingredients are of equal quality, I would opt for an incense without a center bamboo stick. The stick releases a smell that disrupts the blend of aromas from the other ingredients, and has no significant benefits that I’m aware of. On rare occasions, the center stick is made from sandalwood, in which case it would be a high quality incense
• The burn time of the incense – incense with higher quality ingredients will burn longer than lower quality incense of the same length/size
• For Handmade incense, the smoothness of the stick – incense burns better and releases a better blend of aromas if all the ingredients are processed into a fine powder before blending. If the incense shows clumps, this is a sign that the scent will be uneven, and the incense may not even stay lit

All else (shape, length, thickness) being equal, an incense with higher quality ingredients will burn for longer. This became extremely noticeable when we started making our own handmade incense. A handmade full length (21cm) incense stick (with ingredients that we select) burns for up to 50% longer than regular store-bought incense of the same length and thickness.

Of course, if you are wondering about burn time related to the shape of the incense, that’s a different matter. Coil incense burns by far the longest as it is also literally the longest incense due to the circular coils. Length is a pretty reliable indicator of burn time but thickness is not, as the entire cross-section is burning at any one time and it may not necessarily take longer to burn through the thicker stick.

You light the tip of the incense with a flame until it catches fire, allow it to burn for a few seconds, then gently fan out the flame, ensuring that a glowing ember remains. This may need to be repeated several times if the first time doesn’t work. For more details, we have a thorough, step-by-step article to guide you. Once properly lit, place the incense onto the incense holder. Keep the incense and burner on a surface away from wind or sudden air movements (windows, fans, AC, etc).

There are typically two situations where incense need to be put out. First, when an incense stick is first lit and has an open flame. This open flame needs to be put out, leaving a burning ember in order for the incense to continue burning. In traditional Chinese and Japanese culture, you should not blow on the flame with your mouth to put it out. This is because the mouth is considered impure, and incense is an offering to the heavens. You can wave your hand around the flame, or move the entire incense stick from side to side to put out the flame.

The second instance is when you need the incense stick to stop burning, ie, put out the ember. Typically, in traditional Chinese culture, incense sticks are allowed to burn their full length once lit, and it is rare to stop an incense stick half way. However, if for a particular reason this needs to be done, you can cut off the tip with the ember with metal scissors, allowing it drop onto a fire-proof surface, or pinch out the ember with large metal tweezers. Alternatively, some long term users of incense simply pinch the tip with their fingers and put out the ember this way. (They say it's not hot!) In general, we would recommend breaking or cutting your incense beforehand into smaller pieces if you do not intend to burn through the full stick. This way, you can allow each piece of the incense to burn continuously in its entirety without needing to put it out halfway.

There are actually a variety of different explanations for this, and some of the most well known are listed below. I think we can see though that regardless of religion or explanation, the practice of using three incense sticks is entrenched in Chinese culture, and considered a show of respect, whether it be to deities, the heavens, or to certain practices regarded as sacred.

In Daoism, a classic line from The Book of The Way《道德经》states: “One births two, two birth three, three gives birth to all” (一生二，二生三，三生万物). So the number three actually symbolizes “all” in Daoism, and an offering of three incense to the deities is therefore considered an abundant offering.

In Buddhism, the three incense represent the thee pillars of Sila, Dhyana and Prajna, (meaning right conduct, meditation/concentration, wisdom; in Chinese: 戒、定、慧 ). The first incense for Sila is placed in the center, followed by Dhyana on the right, and Prajna on the left.

The third explanation is unrelated to religion. The three incense sticks are considered offerings to the heavens, the earth, and the people, (天、地、人) in this order.