Reboiling water, in the context of this article means, boiling ones, allowing to cool down and then again boiling it. Somehow, Ayurveda does not like this thing.
The above Sanskrit verse means the following –
Once any liquid, water or kashayam (decoction) is boiled and cooled down, if it is re-heated, that liquid acts like Visha – poison.
Besides water, this rule also applies to –
Ghrita – herbal ghees
Taila – herbal oils
Paneeya – herbal drinks and juices involving boiling process
While making Leha – herbal jams like chyawanprash, we make the Kashaya (decoction / herbal tea) first and then to it, other jaggery or sugar etc are added and re-heated.
In this case, the Kashaya is not allowed to cool down and as soon as Kashaya is ready, we just add the other ingredients and continue heating. So, there, the above rule does not apply.
About making oils, Avaleha:
There is another rule (above Shloka)
Ghrita – herbal ghees,
Taila – herbal oils
Guda – jaggery based herbal jams (and Avaleha in general),
It is best to prepare it in more than one day. This is because, the night time has its own beneficial effect on the product.
But here, it cannot be considered as re-boiling. Because, once Kashaya is made, it is added with sugar / oil / ghee. Then boiled for some time, and then by next day, the boiling is continued. Here, the boiling is a continuous process and we are not re-boiling the finished product.
For using oils for massage
Some practitioners heat the massage oil, just before starting massaging. This is, kind of okay, in winters and in cold climate places. Because, if we massage extremely cold oil, it may cause Kapha increase, leading to excess stiffness or Vata Dosha increase. So, heating the oil, just above the room temperature, before massage is agreeable.
Can we heat the market available kashayam, before consumption?
No. There is a wrong assumption to heat the ready-made kashayam that is available in the market, before consumption. This is double dangerous. Here, not only the Kwath, even the preservatives also get heated, leading to complex unhealthy mix. It may cause worse diseases than the patient already is suffering with.
Why Re-boiling water makes it poison?
The answers are not totally convincing. Here is some effort:
The water contains dissolved gases and minerals. Once they are boiled, they reach an activated stage. But if they are cooled and re-boiled, their complex interaction makes it poisonous or unhealthy to consume. In Ayurveda, it leads to formation of Ama – a product of altered digestion and metabolism.
One article says – “you risk concentrating certain undesirable chemicals that may be in your water. Examples of chemicals that become more concentrated include nitrates, arsenic and fluoride” (source)
Another one says –
Nitrates turn into nitrosamines and become carcinogenic. These chemicals have been linked to diseases like leukemia and non-Hodgkin lymphoma as well as various types of cancer.
Meanwhile arsenic accumulates which can result in cancer, heart disease, infertility and neurological problems.
Minerals that are good for us in small doses, such as calcium salts, can be very harmful when re-boiled and can lead to kidney stones and gallstones.
Worryingly, an increase in the level of fluoride can have damaging effects on the cognitive and neurological development of children.
What is wrong with reboiling Kashayam, herbal ghee, oils etc?
Kashay / kwath / decoction simply means boiling herbs with water for some time, filtered.
Like all cooked foods, Kashay is told to be taken when it is freshly made and in hot condition. Kashay making itself is a form of cooking. Only in high Pitta condition, a freshly made kwath is allowed to cool down before consumption.
So, when kashay is freshly made, the water soluble active prinicples of herbs are in activated, charged condition. This, when consumed, gets easily absorbed and quickly show their benefits in the body.
But if Kashayam is re-heated, after cooling down, it looses the charge of active principles and they become very hard for digestion, leading to production of ama – a product of altered digestion and metabolism. This further leads to onset of many diseases.
Same is the case with lehyams, herbal ghees and herbal oils.
This rule also applies to cooked food.
Heating is a process of charging up the active principles in the food and herbs that we consume.
Once they are charged up and activated, they have to consumed so that their energy and total of their phyto-nutrients are easily absorbed by the body.
But once after they cool down and again re-heated, they are not as charged as previously, leading to erratic absorption.
This has been my understanding of this concept thus far. If you have further reasoning to add, please write about them in the comment section below.