Vitamins and minerals are essential to humans as they play essential roles in a variety of basic metabolic pathways that support fundamental cellular functions. In particular, their involvement in energy-yielding metabolism, DNA synthesis, oxygen transport, and neuronal functions makes them critical for brain and muscular function. These, in turn, translate into effects on cognitive and psychological processes, including mental and physical fatigue. This review is focused on B vitamins (B1, B2, B3, B5, B6, B8, B9 and B12), vitamin C, iron, magnesium and zinc, which have recognized roles in these outcomes. It summarizes the biochemical bases and actions of these micronutrients at both the molecular and cellular levels and connects them with cognitive and psychological symptoms, as well as manifestations of fatigue that may occur when status or supplies of these micronutrients are not adequate.

Magnesium deficiency and stress are both common conditions among the general population, which, over time, can increase the risk of health consequences. Numerous studies, both in pre-clinical and clinical settings, have investigated the interaction of magnesium with key mediators of the physiological stress response, and demonstrated that magnesium plays an inhibitory key role in the regulation and neurotransmission of the normal stress response. Furthermore, low magnesium status has been reported in several studies assessing nutritional aspects in subjects suffering from psychological stress or associated symptoms. This overlap in the results suggests that stress could increase magnesium loss, causing a deficiency; and in turn, magnesium deficiency could enhance the body’s susceptibility to stress, resulting in a magnesium and stress vicious circle. This review revisits the magnesium and stress vicious circle concept, first introduced in the early 1990s, in light of recent available data.

Animal and clinical studies suggest complementary effects of magnesium and high-dose pyridoxine (vitamin B6) on stress reduction. This is the first randomized trial evaluating the effects of combined magnesium and vitamin B6 supplementation on stress in a stressed population with low magnesemia using a validated measure of perceived stress. In this Phase IV, investigator-blinded trial (EudraCT: 2015-003749-24), healthy adults with Depression Anxiety Stress Scales (DASS-42) stress subscale score >18 and serum magnesium concentration 0.45 mmol/L–0.85 mmol/L, were randomized 1:1 to magnesium–vitamin B6 combination (Magne B6 [Mg–vitamin B6]; daily dose 300 mg and 30 mg, respectively) or magnesium alone (Magnespasmyl [Mg]; daily dose 300 mg). Outcomes included change in DASS-42 stress subscale score from baseline to Week 8 (primary endpoint) and Week 4, and incidence of adverse events (AEs). In the modified intention-to-treat analysis (N = 264 subjects), both treatment arms substantially reduced DASS-42 stress subscale score from baseline to Week 8 (Mg–vitamin B6, 44.9%; Mg 42.4%); no statistical difference between arms was observed (p>0.05). An interaction (p = 0.0097) between baseline stress level and treatment warranted subgroup analysis (as per statistical plan); adults with severe/extremely severe stress (DASS-42 stress subscale score ≥25; N = 162) had a 24% greater improvement with Mg–vitamin B6 versus Mg at Week 8 (3.16 points, 95% CI 0.50 to 5.82, p = 0.0203). Consistent results were observed in the per protocol analysis and at Week 4. Overall, 12.1% of Mg–vitamin B6 treated and 17.4% of Mg-treated subjects experienced AEs potentially treatment related. These findings suggest oral Mg supplementation alleviated stress in healthy adults with low magnesemia and the addition of vitamin B6 to Mg was not superior to Mg supplementation alone. With regard to subjects with severe/extremely severe stress, this study provides clinical support for greater benefit of Mg combined with vitamin B6.

The effect of a combination of magnesium, vitamins B6, B9, B12, rhodiola and green tea/L-theanine (Mg-Teadiola) on stress was evaluated in chronically stressed, otherwise healthy individuals. Effects on stress-related quality-of-life parameters (sleep and perception of pain) were also explored. Adults with stress for ≥1 month, scoring ≥14 points on the Depression Anxiety Stress Scale (DASS)-42 questionnaire, were randomized (1:1) to receive oral Mg-Teadiola (n = 49) or a placebo (n = 51), for 28 days, with a follow-up assessment on Day 56 (NCT04391452). The primary endpoint was the change in the DASS-42 stress score from baseline to Day 28 with Mg-Teadiola versus placebo. The DASS-42 stress scores significantly decreased from baseline to Day 28 with Mg-Teadiola versus placebo (effect size, 0.29; 95% CI [0.01, 0.57]; p = 0.04). Similar reductions were observed on Day 14 (p = 0.006) and Day 56 (p = 0.02). A significant reduction in sensitivity to cold pain (p = 0.01) and a trend for lower sensitivity to warm pain was observed (p = 0.06) on Day 28. Improvements in daytime dysfunction due to sleepiness (Pittsburgh Sleep Quality Index-7 component score) were reported on Day 28, and were significant on Day 56 (p < 0.001). Mg-Teadiola is effective in managing stress in otherwise healthy individuals. Its beneficial effects on sleep and pain perception need further investigation.

Adequate calcium intake is important for the prevention of bone loss and osteoporosis. For some populations such as those of Southeast Asia where calcium intake is very low, supplements represent a suitable dietary source of calcium. The objective of this study was to compare the relative oral bioavailability of calcium from calcium glucoheptonate, a highly soluble calcium salt containing 8.2% of elemental calcium, to that of calcium carbonate. A single‐dose, randomized‐sequence, open‐label, two‐period crossover study, with a 7‐day washout period, was conducted in 24 Indonesian healthy adult volunteers. After a 12‐hour (overnight) fast, subjects received either two oral ampoules of 250 mg/10 mL of calcium glucoheptonate each or one effervescent tablet of calcium carbonate containing 500 mg of elemental calcium. The relative oral bioavailability of calcium from calcium glucoheptonate as compared to calcium carbonate was 92% within 6 hours and 89% within 12 hours after study drug administration. The 90% confidence intervals for the mean test/reference ratios of the maximum plasma concentration and the area under the concentration‐time curve at 12 hours post‐administration were 77.09%–120.31% and 60.58%–122.30%, respectively. Five subjects experienced a total of eight adverse events which were all mild and transient; no serious adverse events or deaths were reported. These results indicate that calcium glucoheptonate is associated with a high relative bioavailability of calcium compared to calcium carbonate, and is well‐tolerated. Calcium glucoheptonate might thus be a potential choice for calcium supplementation in Southeast Asian populations.

Background: Unexplained fatigue is a common complaint. When underlying disease causes have been eliminated, lifestyle measures and supplementation can be indicated. Elaborating on clinical findings that G115^®, a dry extract from the root of Panax ginseng, combined with vitamins and minerals could alleviate fatigue, this open label study aimed at assessing its effect on perceived fatigue and energy. Methods: Healthy adults self-reporting fatigue (n = 103) completed the Multidimensional Fatigue Inventory questionnaire. They rated their perceptions of mental and physical fatigue, energy, performance, and stress at baseline and 15, 30, 60 and 90 days after a daily intake of 40 mg G115^® formulated with vitamins and minerals. Results: Compared with baseline values, mean self-perception of general fatigue was reduced by −7.55 units [95% CI: −8.44; −6.66] (−41.8%, p < 0.0001) at 90 days. All assessed perception ratings (mental and physical fatigue, reduced activity and motivation, performance, and stress) were significantly and steadily improved from two weeks after supplementation up to study’s end. Overall satisfaction with the ability of the product to reduce fatigue reached 85% at Day 90. Conclusion: Daily intake with G115^® extract formulated with vitamins and minerals suggests an improvement of self-perception of fatigue and energy in a fatigued adult population.