Hydration is the body’s ability to absorb water and to maintain the correct balance of fluid and electrolytes and is essential to human health. Dehydration can adversely affect metabolism, thermoregulation, digestion, and neurological, kidney, and heart function. Aging as well as disease and medications affect water and electrolyte levels in the body and can lead to dehydration in older adults. In this review, we discuss factors contributing to dehydration in older adults, how hydration is measured, and strategies to improve hydration status. We close with a summary of the different areas of focus related to hydration research.

Background: Maintaining adequate hydration is important for overall health and has major implications for athletes involved in physically demanding tasks. While water is viewed as an effective means to rehydrate, and is inexpensive and readily available, electrolyte beverages appear to be more beneficial, in particular for athletes who routinely lose electrolytes through sweating. Nuun tablets contain a mix of electrolytes and are quickly dissolved in water to create an electrolyte-rich beverage. We determined the impact of Nuun tablets on the fluid balance of healthy, exercise-trained men and women at rest. Methods: Eight men (25.9 ± 4.5 yrs) and 10 women (28.2 ± 9.4 yrs) ingested either water only or water with Nuun electrolyte tablets, at both a single and double strength concentration, in random order, on three occasions separated by approximately one week, in a fasted and euhydrated state. A total of 1 L of fluid was ingested at each visit over a 30 min period. Urine was collected from each subject at 0, 1, 2, 3, and 4 h post-ingestion. Urine mass values were used to calculate fluid balance and the beverage hydration index (BHI; i.e., the volume of urine produced after drinking the Nuun beverages, relative to that of water only—control condition). Heart rate and blood pressure were measured throughout the four-hour period, while body weight was measured at the start and end of the experiment. Results: Neither heart rate nor blood pressure were impacted by beverage consumption. Nuun tablets resulted in a lower urine output compared to water, with fluid balances for both concentrations more favorable compared to water (p < 0.05), beginning at 2 h post-ingestion and continuing at the 3 h and 4 h times. Body weight loss was less with Nuun at the single dose (0.38 kg; p = 0.02) and double dose (0.43 kg; p = 0.08), compared to water (0.57 kg). The BHI was higher for Nuun (single dose in particular) compared to water at both 2 h (p = 0.05) and 4 h (p = 0.02). Conclusion: The addition of Nuun electrolyte tablets to water improves the fluid balance and BHI in healthy men and women. Results were similar for both concentrations, suggesting that additional electrolytes are not necessary when in a rested state. Future studies should determine the impact of various concentrations of the Nuun beverage during physical exercise—in particular, exercise in the heat, when sweat loss may be highest.

Background: Maintaining adequate hydration is critical to optimal health, well-being, and performance. Those who are physically active in stressful environments, such as warm and/or humid scenarios, may be at particular risk for dehydration with ensuing loss of electrolytes, leading to sluggishness and impaired physical performance. Methods: We evaluated an electrolyte and amino acid product containing L-alanine and L-glutamine, as well as select vitamins [B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B12 (cobalamin), and vitamin C (ascorbic acid)]. Subjects (n = 40; four groups, n = 10) were randomized to consume either a placebo packet or one, two, or three packets daily of the test product for 4 weeks with site visits at 0, 2, and 4 weeks. We tested safety and tolerability by analyzing hematological parameters (complete blood counts), metabolic parameters (hepatic, renal, acid–base balance), urinalysis end products, thyroid status [T3 (triiodothyronine), T4 (thyroxine), TSH (thyroid-stimulating hormone)], tolerability (via questionnaire), vital signs, and dietary intake. Results: Statistical analyses displayed ten significant main effects (p < 0.05) with white blood cells, lymphocytes, neutrophils, urinary pH, thyroxine, urination frequency, calcium, calories, fat, and cholesterol. Interactions for time and group (p < 0.05) were observed for MCV, eGFR, potassium, overall tolerability, bloating, and cramping—demonstrating mild GA disturbances. Little to no change of physiological relevance was noted for any outcome variable, regardless of dosing level. Conclusions: Our results indicate the product was well-tolerated at all dosing levels and no significant adverse changes occurred in any of the test parameters compared to the placebo group, indicating relative safety of ingestion over a 4-week treatment period, at the volumes used, and outside the context of physical stress.

Major depressive disorder (MDD) is the most common mood disorder among adults. Despite the wide use of pharmacological agents by those with MDD, the evidence indicates that only a small fraction of patients benefits, and many individuals using antidepressant therapy relapse. Side effects are numerous with antidepressants, which can be a factor in patient medication compliance. Along with psychotherapy and fine-tuning lifestyle components, another emerging option in treating MDD is the use of bioactive natural products known as nutraceuticals. We present the scientific findings specific to select nutraceuticals (e.g., omega-3 fatty acids, S-adenosyl-methionine, folate-based compounds, and vitamin D) either as a monotherapy or as adjunctive therapy to a pharmaceutical antidepressant, for treatment of MDD. Many studies demonstrate that nutraceuticals result in a decrease in depressive symptoms with fewer side effects as traditional medications and have the potential to improve the result of antidepressants, especially in individuals experiencing resistance to medication. From a therapeutic perspective, a holistic approach incorporating psychotherapy, pharmacological therapy, and lifestyle factors (inclusive of nutraceutical use) appears most logical and could provide for enhanced treatment efficacy.

Alpha Hope is a dietary supplement containing pyrroloquinoline quinone and elemental magnesium, which produces molecular hydrogen (H₂ gas) when dissolved in water. We determined the impact of Alpha Hope on Nrf-2, peroxisome proliferator-activated receptor-gamma coactivator (PGC-1α), and citrate synthase (CS) activity in C2C12 myoblasts. Alpha Hope was titrated to three concentrations of pyrroloquinoline quinone (PQQ) (10 nM, 100 nM, 1000 nM) and treated on C2C12 for 48 h. Nrf-2 and PGC-1α levels were measured using Western blot analysis. CS activity was measured according to previously described methods. Treatment significantly increased Nrf-2 and PGC-1α protein levels in C2C12 myoblasts, with no change for CS. For Nrf-2, values for both the 100 nM (p = 0.046) and 1000 nM (p = 0.011) concentrations were higher than control. For PGC-1α, values for both the 100 nM (p = 0.039) and 1000 nM (p = 0.017) concentrations were higher than control. In a small human pilot study, subjects consumed the Alpha Hope product daily for four weeks, with no adverse effects, with some subjects noted as “responders” to treatment. Alpha Hope can significantly increase both Nrf-2 and PGC-1α in a concentration-dependent manner. Healthy men and women who ingest the product daily can do so without adverse effects.

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