The oceans have helped sustain life on Earth for billions of years and will likely continue to do so far into the future. Oceans have an abundance of minerals like calcium, phosphorus, magnesium, iron, and copper, which are essential nutrients for living organisms. In Japan, deep-sea water (or DSW) is commonly used for drinking, cosmetic purposes, and as seasoning. Recent evidence indicates that DSW has numerous health benefits. However, the exact mechanism behind these benefits is not known.
It is also difficult to compare mineral water sources like DSW since they have different hardnesses, which is a term for the amount of minerals in the water. Drinking water of a high hardness could be dangerous to humans. Now, a team of scientists, led by Professor Koji Fukui of Shibaura Institute of Technology (SIT) and including Yugo Kato, Ph.D., from SIT, Mr. Hirotsugu Takenaka from Dydo-Takenaka Beverage Co., Ltd., and Masahiro Kohno, Ph.D., from SIT, explored the biological effects of DSW in obese mice. They also determined which hardness of DSW was most beneficial. The team’s findings were published on 25 April, 2022, in Volume 14, Issue 9 of the journal nutrients.
First, the researchers prepared DSW extract-added water of different levels of hardness (200, 300, and 500) from DSW taken off the coast of Muroto city, Kochi Prefecture. They then administered the DSW extract-added water to obese mice over two months and evaluated if it had any effect on their cognitive and coordinative functions and also on their blood and biochemical parameters. These mice were compared with control mice that were fed the same high-fat diet, but no DSW extract-added water. The effect of DSW on cognitive and coordinative functions was evaluated by using various tasks. To determine the mechanism of cognitive improvement in the tests, the expression of neurotrophic factors and their receptors in the brain was evaluated. Quantitative analysis was conducted using spectroscopy.
“Although we did not observe an anti-obesity effect for any hardness level in the obese mice, the cognitive and coordinative functions of each DSW extract-added water-treated group were significantly improved compared to the control mice,” says Prof. Fukui. Treatment with DSW extract-added water significantly increased hippocampal NGF secretion in the obese mice.
Additionally, serum parameters like blood urea nitrogen, inorganic phosphorus, amylase, and glucose were decreased in the DSW extract-added water group compared to the control group, indicating a positive impact on renal function. A qualitative analysis of DSW extract-added water at a hardness level of 300 revealed higher concentrations of potassium and magnesium (11 and 7 times that of filtered tap water, respectively). Interestingly, sodium levels for water at this hardness level were found to be lower. “It is important to keep sodium ion concentrations low when concentrating DSW. It is well known that high sodium levels are a high-risk factor for diabetes, high blood pressure, and cardiovascular risk,” states Prof. Fukui.
The researchers’ findings provide new insights on the amount of mineral nutrients safe for chronic intake through drinking water. When asked about the broader applications of this research, Prof. Fukui surmises: “A continued intake of beverages containing moderate mineral levels may help maintain proper health. It may reduce the risk of developing various age-related illnesses, such as renal disease, high blood pressure, cognition and coordination abilities, and lipid metabolism disorders.”
About Shibaura Institute of Technology (SIT), Japan
Shibaura Institute of Technology (SIT) is a private university with campuses in Tokyo and Saitama. Since the establishment of its predecessor, Tokyo Higher School of Industry and Commerce, in 1927, it has maintained “learning through practice” as its philosophy in the education of engineers. SIT was the only private science and engineering university selected for the Top Global University Project sponsored by the Ministry of Education, Culture, Sports, Science and Technology and will receive support from the ministry for 10 years starting from the 2014 academic year. Its motto, “Nurturing engineers who learn from society and contribute to society,” reflects its mission of fostering scientists and engineers who can contribute to the sustainable growth of the world by exposing their over 8,000 students to culturally diverse environments, where they learn to cope, collaborate, and relate with fellow students from around the world.
About Professor Koji Fukui from SIT, Japan
Prof. Koji Fukui is a professor in the Department of Bioscience and Engineering at Shibaura Institute of Technology. Currently, his research is focused on oxidative-related neurodegenerative disorders and the prevention of neuronal degeneration using antioxidant substances. A respected and senior researcher, he has more than 71 publications to his name and numerous awards, including the Topics contribution award from the Japan Vitamin Society, an academic award from the Society for Free Radical Research Japan, and the young investigator award from the Society for Free Radical Research Asia, to name a few.
Method of Research
Subject of Research
Effect of extract-added water derived from deep-sea water with different hardness on cognitive function, motor ability and serum indexes of obese mice
Article Publication Date
The authors declare no conflict of interest.