关于功能水的研究如火如荼，特别是在日本和韩国，民众对功能水非常热捧，随着经济发展和环境污染程度的加重，人们希望通过饮用水获得健康愿望逐渐增加，根据估算现在全球功能水的市场额度有3180亿美元，这可不是一个小数目。最近有人对功能水的功能，特别是延长寿命的功能提出质疑，这个文章是以给编辑信的方式发表，不过他们也有自己的研究数据。

所谓功能水，是指把水经过电场、磁场、电磁场、超声等处理过的水，使水发生某些改变，普遍的看法是这些经过处理的水对健康有利。最近比较多的研究是氢气溶解水的研究，例如发现对动物束缚应激动导致的神经功能损伤。还如使用电解或金属处理，使水变成碱性含氢气的还原水，研究发现这种水具有抗癌和抗糖尿病效应，对动脉硬化等疾病也具有作用。尽管具体的分子机制不明确，但目前认为这种水具有对抗活性氧的效应，又由于活性氧增加是衰老的重要原因，因此推测这种水具有抗衰老的效应。

但我们用果蝇的实验结果并没有证明这类水具有抗衰老的效应。具体细节请看全文：

Does alkaline-reduced hexagonal water delay the aging process in Drosophila?

1. Kyung-Eun Rheem^1,†,
2. Yi-Rang Lim^1,†,
3. Byung-Sub Lee¹,
4. Su-Kyung Lee¹,
5. Ki Moon Seong²,
6. Dong-Hoon Hyun³,
7. Kyung-Jin Min¹

Article first published online: 21 DEC 2011

DOI: 10.1111/j.1447-0594.2011.00713.x

Dear Editor,

Water is the most common substance on earth and many people want to drink clean water. Owing to demands, altered water – water exposed to external energy fields such as electrical, magnetic, electromagnetic, ultrasound and vortex implosion – has been developed. There is a common belief that altered water makes a positive impact on health. Recent studies found that consumption of water containing hydrogen at a saturated level (hydrogen water) reduced oxidative stress and prevented stress-induced decline in learning and memory caused by chronic physical restraint.¹ Recent studies also have shown that alkaline-reduced water (ARW) – water produced either by electrolysis or by chemical reaction with alkaline metals – has anticancer and antidiabetic effects. Mice fed with ARW showed delays in tumor growth and lengthened survival.^2,3 In addition, there is evidence that long-term ARW consumption reduced glucose, triglyceride and cholesterol levels in mice.⁴ Although the molecular mechanisms behind those effects are not yet clearly understood, the capacity to reduce reactive oxygen species (ROS) by ARW is believed to be a reason behind these positive effects.^5,6 Because ROS is a cause of aging⁷ and reduction of ROS led to extended lifespan in many organisms,⁸ it is hypothesized that ARW has anti-aging effects.

Hexagonal or structured water is another type of altered water. Water is able to form different structures, depending on how individual molecules bond together. Advocates of structured water claim that biological organisms prefer the six-sided (hexagonal) ring-structure of water.⁹ Recent clinical studies showed that a hexagonal water product was more effective at hydration than distilled water and there was a trend toward lower blood sugar levels in just 4 weeks in diabetic patients with hexagonal water drinking.¹⁰ Hexagonal water also appears to enhance immune function. When mice were given a hexagonal water product while a control group was given de-ionized water, 60% increase in lymphocyte production was measured in the hexagonal water group, indicating a significant improvement in immune function.¹¹ It has been also claimed that hexagonal water could delay the aging process. The amount of hexagonal water decreases with age and aging is caused by a loss of hexagonal water from organs, tissues and cells, and an overall decrease in total body water.⁹ However, there are also claims that the health benefits of altered water are fraudulent, because claims by altered water manufactures contradict the basic laws of physics and chemistry.¹² Thus far, there has been no attempt to assess the effects of altered water on the aging process in any organisms. We therefore elect to investigate the effects of altered water on the lifespan in Drosophila.

Alkaline-reduced hexagonal water was produced with an instrument using electromagnetic implosion, and it was provided to adult flies in the form of a sucrose–yeast diet. The pH of the distilled water was reduced from 7.16 ± 0.4 to 9.84 ± 0.2 with the instrument, confirming the production of ARW. Adult sucrose–yeast diets were prepared with 10 g sucrose, 10 g yeast, 2.5 mg kanamycin, 10 mg tetracycline, 1.1 mL of a 20% tegosept and 0.79 g agar per 100 mL of distilled water, or alkaline-reduced hexagonal water. Newly eclosed Canton-S adult flies were collected over 48 h and were randomly assigned to 500 mL demography cages to the final density of 100 females and 100 males per cage. Food vials were affixed to separate cages and changed every 2 or 3 days, at which time dead flies were removed and recorded.¹³ Our results show that alkaline-reduced hexagonal water had no effect on the lifespan of either female or male flies (Fig. 1a,b). Measurements of flies' mean and median lifespan fed with alkaline-reduced hexagonal water containing media indicate that their lifespan had not been significantly extended, when compared to flies maintained on distilled water containing media (Table 1).

Figure 1. The effects of altered water (a,b) and water transport gene (c,d) on the lifespan of Drosophila. Male (a) and female (b) survivorship when maintained on media containing distilled water (DW) or alkaline-reduced hexagonal water (ARW). Male (c) and female (d) survivorship when water transport gene, DRIP, is overexpressed (+RU) or not (−RU). Survivorship is plotted with the data of three replicate cages for each treatment combined. See Table 1 for statistical analysis.

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Advocates of hexagonal water claim that the aging process is accompanied by reduction of water content in the body; drinking hexagonal water can delay the aging process because hexagonal water is easily transported into cells. We tested this hypothesis by genetic manipulation of the water transport gene. Water is transported through highly water-permeable membranes via water-selective pores: the water channels. Aquaporins accelerate the movement of water and other solutes across the biological membranes. Drosophila have aquaporin-like water channel genes, DRIP (Drosophila integral protein).¹⁴ We increased the expression of DRIP using the UAS-GAL4 system¹⁵ which renders temporal and spatial expressions of genes possible. Male EP (Drip) flies were crossed with females with daughterless-gene switch gal4 driver or actin-gene switch gal4 driver, and the survival of F₁ offspring was monitored with or without RU486 supplementation. In the gene-switch gal4 system, gal4 is expressed only when RU486 is present in the media. Our results show that survival of flies with overexpressed DRIP gene (+RU) was not significantly different from that of flies with normal DRIP gene expression (−RU) either with daughterless-gene switch driver (Fig. 1c,d; Table 1) or actin-gene switch driver (data not shown). As a positive control, the validity of the gene switch driver was tested by overexpressing the hsp26 gene which is known to extend lifespan when overexpressed.¹⁶ As expected, survival of flies with overexpressed hsp26 gene was significantly extended compared to that with normal hsp26 gene expression (Table 1). Although both hexagonal water and overexpression of DRIP have no effect on the lifespan of Drosophila in this study, it is still possible that water transport is associated with the aging process because the lifespan of Drosophila on a restricted diet is regulated by water content in the media.¹⁷

The size of the water market is estimated to be $US 318 billion globally and is rapidly increasing due to pollution and economic growth. Many people follow the “well-being” trend and seek “healthy” water. Demands have driven many vendors to develop altered water, which is being advertised as providing health benefits. However, the impact on health by altered water has not been validated scientifically. Most altered water is produced by electrical devices that utilize electrolysis to generate ionized and alkalinized water. Many water ionizers originate from Japan and Korea, countries in which many people believe altered water has health benefits. This is in contrast to the views held by many scientists in Western countries that altered water is yet another scam.

We do not yet have adequate information on which to judge the impact of altered water on health. It is the scientists' responsibility to study altered water further. Our results indicate that ARW and hexagonal water has no impact on the aging process, as far as Drosophila is concerned.

This work was supported by a research grant from the Inha University (INHA-38335).

Nagata K, Nakashima-Kamimura N, Mikami T, Ohsawa I, Ohta S. Consumption of molecular hydrogen prevents the stress-induced impairments in hippocampus-dependent learning task during chronic physical restraint in mice. Neuropsychopharmacology 2009; 34: 501–508.

Lee KJ, Park SK, Kim JW et al. Anticancer effect of alkaline reduced water. J Int Soc Life Inf Sci 2004; 22: 302–305.

Ye J, Li Y, Hamasaki T et al. Inhibitory effect of electrolyzed reduced water on tumor angiogenesis. Biol Pharmaceut Bull 2008; 31: 19–26.

Jin D, Ryu SH, Kim HW et al. Anti-diabetic effect of alkaline-reduced water on OLETF rats. Biosci Biotechonol Biochem 2006; 70: 31–37.

Hanaoka K. Antioxidant effects of reduced water produced by electrolysis of sodium chloride solutions. J Appl Electrochem 2001; 31: 1307–1313.

Li Y, Hamasaki T, Nakamichi N et al. Suppressive effects of electrolyzed reduced water on alloxan-induced apoptosis and type 1 diabetes mellitus. Cytotechnology 2011; 63: 119–131.

Harman D. The aging process. Proc Natl Acad Sci U S A 1981; 78: 7124–7128.

Beckman KB, Ames BN. The free radical theory of aging matures. Physiol Rev 1998; 78: 547–581.

Katayama S. Aging Mechanism Associated with a Function of Biowater. Physiol Chem Phys Med NMR 1992; 24: 43–50.

Wang ZY, Zhou ZC, Zhu KN et al. Microclustered water and hydration. Asia Pac J Clin Nutr 2004; 13: S128.

Pan JG, Zhu KN, Zhou MC Wang ZY. Low resonant frequency storage and transfer in structured water cluster. Systems, Man and Cybernetics, 2003. IEEE International Conference on 2003; 5: 5034–5039.

Hairston JE, Rodekohr D, Brantley EF, Bice LL. Drinking water and water treatment scams. Timely Information. Alabama Cooperation Extension System . 2003; 1–17.

Min KJ, Tatar M. Drosophila diet restriction in practice: do flies consume fewer nutrients? Mech Ageing Dev 2006; 127: 93–96.

Kaufmann N, Mathai JC, Hill WG, Dow JA, Zeidel ML, Brodsky JL. Developmental expression and biophysical characterization of a Drosophila melanogaster aquaporin. Am J Physiol Cell Physiol 2005; 289: C397–C407.

Duffy JB. GAL4 system in drosophila: a fly geneticist's swiss army knife. Genesis 2002; 34: 1–15.

Wang H-D, Kazemi-Esfarjani P, Benzer S. Multiple-stress analysis for isolation of Drosophila longevity genes. Proc Natl Acad Sci U S A 2004; 101: 12610–12615.

Ja WW, Carvalho GB, Zid BM, Mark EM, Brummel T, Benzer S. Water- and nutrient effects of dietary restriction in Drosophila lifespan. Proc Natl Acad Sci U S A 2009; 106: 18633–18637.