It is widely known that soda, beer and coffee are bad for your teeth.
Bottled water, however, seems harmless.
But dentists warn that is not always the case.
Some of the most popular brands of bottled waters have dangerous pH levels and lack essential fluoride, which can cause cavities.
However, it is impossible to know from the label which ones are the safest – so we tested the pH levels of nine top brands to see which ones were the best and worst.
The pH level can range from zero to 14. On that scale, seven is neutral, anything under that is acidic and anything higher is alkaline.
Our investigation found that samples of four of nine popular bottled water brands were very acidic. The brands – Smartwater, Dasani, Aquafina and Voss – had a pH level of 4
HOW DO BOTTLED WATER BRANDS AFFECT YOUR TEETH?
We tested nine bottled water brands to see their pH levels. Brands with pH levels closer to zero are more acidic and can erode your tooth enamel. Brands with pH levels between seven and 14 are alkaline.
Drinking acidic water will harm your teeth, warns Dr Eunjung Jo of Astor Smile Dental.
‘Our enamel starts to erode at a pH level of 5.5 so it’s best to avoid any drinks with a pH that is lower than 5.5.’
Dr Jo also said that the damage done to your teeth increases proportionately with the time you spend sipping on a drink so spending three hours drinking a coffee is more harmful than downing it in 30 minutes.
‘The longer you sip and they stay in your mouth, [the] damage is bigger,’ she said.
She added that bottled water is not worse for your teeth than sodas, beer or coffee and she thinks Fiji water is the best for your teeth while Dasani, Voss and Smartwater are the worst.
The lack of fluoride – a healthy ion that is good for tooth enamel – in bottled water can also be harmful.
Tap water is regulated by the government, which makes sure it has accurate fluoride levels, but bottled water often lacks proper amounts of it.
Dr Tema Starkman of High Line Dentistry said it is important to make sure you are always consuming fluoride.
She said that this is especially important for children between the ages of zero and five whose teeth are still developing.
If these children do not receive proper fluoride levels they can develop hypo-fluorosis, a condition that can leave white spots on their teeth, she said.
‘If they are not drinking a significant amount of tap water and are only drinking filtered, bottled water without measured levels of fluoride, then they could developmentally have problems.’
ACIDIC: Smartwater, which has a pH level 4, was among the brands that Dr Eunjung Jo said were worst for your teeth
NEUTRAL: Poland Spring’s pH level is seven, which is neutral. If a water’s pH level drops below 5.5, it can erode your tooth enamel
ALKALINE: Evian’s sample was the most alkaline of the nine bottled water samples we tested. Its pH level is 8.5. While there is proof that alkaline water can help prevent bone loss, there is no evidence that this effect will last over a long period of time
IS ALKALINE WATER BAD FOR YOU?
Proponents of alkaline water say it can boost one’s metabolism, neutralize acid in the bloodstream and help bodies absorb nutrients, according to the Mayo Clinic.
Some say that it can slow the aging process and help prevent diseases.
There is evidence that alkaline water can help prevent bone loss but the Mayo Clinic said that there is not sufficient proof that this effect will last in the long term.
She said there is evidence that drinking tap water is good for children’s teeth.
‘The studies say that during the developmental stage of growth for children, accurate fluoride levels in tap water could contribute to healthy enamel formation.’
The CDC said children who live in communities with non-fluoridated tap water have more decayed teeth than their counterparts who live areas with fluoridated tap water.
The problem also affects adults, Dr Starkman said. ‘If an adult has a cavity, which is a bacteria that’s entered a part of the enamel that’s weakened, if there is not a source of fluoride in their drinking water, then, definitely, that can contribute to more cavities.’
But she said that people drinking only bottled water can get fluoride from fluoridated toothpaste or rinses.
‘Usually when you brush your teeth you’re getting some fluoride from the water in the sink,’ she said.
Dr Starkman recommended a balance of bottled and tap water. She said even young children can have bottled water when they are on the go but tap water is good for them to have every day.
‘They shouldn’t avoid it. A lot of people try to avoid tap water. There’s no reason. It’s definitely healthy,’ she said.
Dr Jo said she recommends that parents should give their children tap instead of bottled water.
The American Dental Association said that drinkers of bottled water may be missing out on the benefits of fluoride.
‘Drinking water with fluoride, often called “nature’s cavity fighter”, is one of the easiest and most beneficial things you can do to help prevent cavities,’ the association said.