Hydrogen Water Helps Young Fish Survive Cold Temperature Stress
- Authors
- Qianqian Xu, Haolin Wang, Xue Chen, Long Chen, Paini Xin, Hua Liu, Ying Yang
- Journal
- Antioxidants
- Year
- 2026
- DOI
- 10.3390/antiox15060742
- Study Type
- Largemouth Bass (Micropterus salmoides)
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- China
- Health Condition
- Oxidative Stress
- Body System
- Hepatic (Liver)
TL;DR
Low-dose hydrogen-rich water improved growth and helped juvenile largemouth bass tolerate acute cold stress by reducing tissue damage and strengthening antioxidant defenses.
Key Finding
Hydrogen-rich water at 0.3 mg/L concentration improved growth and reduced cold-stress damage in juvenile largemouth bass by boosting their natural antioxidant defenses and beneficial gut bacteria.
Summary
Researchers tested whether water containing dissolved hydrogen gas could help young largemouth bass survive sudden cold stress. Fish were raised in regular water or water with different amounts of hydrogen for 30 days, then exposed to cold temperatures for 2 days. The group receiving the lowest hydrogen concentration (0.3 mg/L) showed better growth, less damage to their liver and intestines, stronger antioxidant defenses (natural protective systems in cells), and more beneficial bacteria in their digestive systems compared to control fish.
Practical Takeaway
This is a fish study, not human research, so it cannot directly inform hydrogen water use in people. The results suggest hydrogen may help aquatic animals cope with temperature stress, but whether similar benefits would apply to humans or other species remains unknown. Early evidence indicates hydrogen's potential mechanism involves strengthening cellular antioxidant systems, though much more research would be needed to establish safety and effectiveness in humans.
Abstract
Hydrogen-rich water (HRW) is an aqueous solution containing dissolved molecular hydrogen. This study evaluated its effects on juvenile largemouth bass (Micropterus salmoides) under acute low-temperature stress. A total of 480 juveniles (2.4 ± 0.5 g) were randomly assigned to four groups: the control group was reared in standard water; the treatment groups were exposed to different hydrogen concentrations, specifically H1 (0.3 mg/L), H2 (0.5 mg/L), and H3 (0.9 mg/L). The fry were reared at 26 ± 0.5 °C for 30 days, followed by acute low-temperature stress (11 ± 0.5 °C) for 48 h. Samples were collected at 0, 8, 24, and 48 h. Results showed that after 30 days of HRW rearing, the final body weight (FBW), specific growth rate (SGR), and condition factor (CF) of the H1 group were significantly increased, while the H3 group only increased CF. No significant differences were observed in hepatopancreas somatic index (HSI) and survival rate (SR) among groups. Acute low-temperature stress induced liver and intestinal damage, which were alleviated in the H1 group. The H1 group exhibited significantly increased SOD, CAT, and GSH-Px activities in the liver, as well as CAT and SOD in the intestine and gills, while reducing MDA levels, thereby enhancing the antioxidant capacity. The H1 group significantly upregulated the antioxidant genes expression (sod, cat, and gsh-px mRNA levels) in the liver and gills but downregulated them in the intestine. 16S rDNA analysis revealed that HRW increased intestinal microbiota and the relative abundance of Bacillota. In conclusion, the H1 group significantly improved growth performance, mitigated acute low-temperature damage, enhanced antioxidant capacity, and increased the relative abundance of Bacillota in the intestines. This provides an innovative, safe, and effective solution for aquaculture industries confronting low-temperature challenges.