137 Animal studies in the 1990s by researcher Phyllis Mullenix, at the Harvard-affiliated Forsyth Research Institute, showed that rats exposed to fluoride in the womb were much more likely to behave in a hyperactive manner later in life. This could be due to direct damage or alteration to the development of the brain. (Mullenix's adviser told her she was "jeopardizing the financial support" of her institution by "going against what dentists and everybody have been publishing for fifty years, that [fluoride] is safe and effective," and she was fired shortly after one of her seminal papers was accepted for publication,according to Grandjean and a book by investigative journalist Christopher Bryson called The Fluoride Deception.)
Multiple studies also suggest that kids with moderate and severe fluorosis—a staining and occasional mottling of the teeth caused by fluoride—score lower on measures of cognitive skills and IQ. According to a 2010 CDC report, a total of 41 percent of American youths ages 12 to 15 had some form of fluorosis. Another study showed structural abnormalities in aborted fetuses from women in an area of China with high naturally occurring levels of fluoride.
There have also been about 40 studies showing that children born in areas home to water with elevated levels of this chemical (higher than the concentrations used in U.S. water fluoridation) have lower-than-normal IQs. Grandjean and colleagues reviewed 27 such studies that were available in 2012, concluding that all but one of them showed a significant link; children in high fluoride areas had IQs that were, on average, seven points below those of children from areas with low concentrations of the substance.
119 It would be hard to improve the healthfulness or cleaning power of water without adding any chemicals or supplements to it. But companies are claiming to do just that by "ionizing" water. Enagic USA's Kangen Water Companies are selling machines that put drinking water through an "ionization" process. According to the companies, the process, also called "electrolysis," is accomplished using negatively and positively charged electrodes. In the process, water atoms give electrons to the electrodes or receive them, according to a graphic on Chanson Water USA Inc.'s website. The result is a chemical reaction that results in water becoming more acid or alkaline. Tap water typically has a pH of around 7, or neutral; alkaline water has a pH of more than 7; acidic water, less than 7. Companies say alkaline water has a variety of benefits, ranging from giving you energy to counteracting unhealthy effects of acidic foods you eat.
Some scientists, however, say there aren't any good studies supporting the ionized-water companies' marketing claims. Alkaline Water Machines, long sold internationally, have been generating increased interest in the U.S. during the past couple of years, says Pauli Undesser, director of regulatory and technical affairs at the Water Quality Association, a nonprofit trade group for the water-treatment industry. Earth Trade Water Inc., Carlsbad, Calif., posts testimonials from professional athletes who say its ionized alkaline water boosts their performances by providing better hydration and aiding "energy" and "focus." A Laguna Hills, Calif., unit of Chanson Taiwan LLC, says on its website that its ionized water has smaller clusters of water molecules than ordinary water and these "microclusters" are better able to "penetrate into more places in the body." In a marketing brochure, Enagic USA Inc., a Los Angeles unit of Japan's Enagic Co., says its "Healthy Kangen Water"—which has a pH of 8.5 to 9.5—"helps your body balance the acidic effects" of eating foods such as meat and eggs. Enagic's Leveluk SD501 model, which sells for $3,980, uses seven electrodes. Enagic also says Kangen water tastes better with "superior mouth-feel." In an informal blind taste test at a local spa offering Kangen water, I found the Kangen water tasted soft and velvety, but with a mineral aftertaste, compared with ordinary tap water. The machines, which typically range from $1,000 to $6,000, are generally attached to a faucet, but some models go under the sink. The alkaline water, which the companies say is ideal for drinking and cooking, comes out of one of the machines' spigots, while acid water, which can be used for cleaning, comes out of another. The degree of alkalinity is often adjustable. The machines have a built-in filter, which filters impurities just like any other water filter.