Water pulling as effective as oil pulling for teeth and gums?
First trial study: no statistically significant difference in oral bacteria and plaque reduction potential
While I originally learned from a German source1 that water pulling apparently was as effective for (general) health purposes as oil pulling, we now have at least one small scientific study indicating that the two could indeed be next to equivalent regarding their ability to dramatically reduce oral bacteria and dental plaque counts.
Aired on 28th October 2013 on the UK's Channel 4 "Health Freaks" series2, a 9-day trial under the supervision of microbiologists and dentists from the Eastman Dental Institute (London) investigated the effects of prolonged swirling with coconut oil versus swirling with distilled water on plaque and oral bacteria counts of 18 volunteers.3
Randomly split into two groups of 9 individuals each, the volunteers of the first group were asked to swish coconut oil every morning for ten minutes over the nine days, while the second group observed the same routine using plain distilled water.
To ascertain whether there would be any changes in bacterial counts at the end of the trial, saliva samples were taken and analysed both at the beginning and end of the nine-day period, additionally, differences in the amount of plaque were assessed.
Presumably to ensure that participants followed instructions correctly, they were asked to create home videos of their morning swishing routine.
Results of 9-day study: oil pulling vs. distilled water pulling
All participants showed a massive (80 percent) reduction in the amount of bacteria they carried in their mouth after nine days of oil or water pulling, respectively, with both groups showing near-identical results. While the coconut oil users did show a slightly greater reduction in the harmful bacteria, the advantage was too small to be statistically significant, i.e. did not allow the conclusion that it was the coconut oil that made the difference.
All participants showed a reduction in plaque levels as well, again with no advantage in the group that had used the coconut oil.
In summary, the study was unable to demonstrate any significant difference between oil pulling and distilled water pulling's ability to reduce oral bacteria, rather the drop in bacterial counts was due to the simple act of vigorously swishing fluid through the teeth for ten minutes every morning.
On the trial's use of distilled water rather than tap water
Distilled water is likely to have been used to eliminate any skewing of the results due to differences in the quality of the water used by the individual participants.
Eastman Dental Institute's reaction
Interestingly, contradicting the television report2, the Institute maintains on its website that the trial demonstrated that swirling coconut oil for nine days did not lessen dental plaque and that an effect on bacterial populations from swirling was not shown either since the study included no third (control) group that did not swish.
The Institute intimates that the observed bacterial count reduction may be owed to the fact that the participants might have upgraded their 'normal' oral hygiene routines in addition to swirling, since it was "not uncommon for participants in oral hygiene studies to have better hygiene when they know they are being studied".
That the oil (or water) pulling itself played the major if not decisive part in the lowered bacteria numbers seems to be corroborated, however, by a number of scientific research studies (randomized, controlled, and even triple-blinded) into oil pulling's dental health benefits as well as by many personal testimonials (see Oil pulling for [dental] health).
Incidentally, Eastman Dental Institute also omitted to mention that Alan3 who reported having cured his bleeding gum problem via coconut oil pulling, also said that he didn't need any new fillings since starting the routine.
On using water vs using oil
Granted that intense swishing with water (or herbal tea) may have the same detoxifying effect as practising the same with oil, the former of course has several advantages including:
water is near-always available
water is much less expensive than oil
using water takes a major burden from the waste water purification systems (if you do use oil, make sure to spit out into a paper towel to protect the environment)
as with oil, one can also add various healing herbs to water to enhance its flavour and/or effect.
More on coconut oil for teeth
See Another tooth-friendly oil? Virgin coconut oil
1 Erika Herbst's landmark book "Die Heilkunst von Morgen" [The Healing Arts of Tomorrow]
2 presented by three medical doctors
3 The trial was triggered by Alan, one of the program's guest, a 43 year old man who attributed the cure of his gingivitis to the practice of oil pulling using coconut oil. He also reported not having had any new fillings since starting on the routine while having received many fillings beforehand.