Clinical Studies

Flow-mediated dilation rose from 10.25% to 16.71% over 42 days with 375 mg of MaxiNOs a day, higher than placebo from the first dose on.

Resistance-trained men taking 750 mg of OptiNOs a day added an average of 27 kg (60 lb) to their bench press over 6 weeks, compared with 3 kg (6 lb) on placebo.

The ISSN concludes that 4 to 6 g of beta-alanine daily for at least two to four weeks raises muscle carnosine and improves exercise performance, with the clearest effects in open end-point tasks lasting 1 to 4 minutes.

Creatine raises intramuscular creatine stores and improves high intensity exercise performance and training adaptations, and short and long term use of up to 30 g per day for 5 years is safe and well tolerated.

Creatine combined with resistance training added 4.43 kg of upper-body strength and 11.35 kg of lower-body strength over placebo, with gains found in males but not in the small female sample.

Pooling 26 trials, melatonin shortened sleep onset latency and increased total sleep time, with the effect peaking at 4 mg per day and improving when the dose was taken about 3 hours before the desired bedtime.

Protein supplementation added 2.49 kg to one-repetition-maximum strength and 0.30 kg of fat-free mass over resistance training alone, with no further fat-free mass gain above a total intake of 1.62 g/kg/day.

A total daily protein intake of 1.4 to 2.0 g per kg of body weight is sufficient for most exercising people to build and maintain muscle, taken as servings of 20 to 40 g containing 700 to 3,000 mg of leucine every 3 to 4 hours.

Caffeine at 3 to 6 mg per kg of body mass gives small to moderate gains in muscular endurance, strength, sprinting, jumping and throwing, with the most consistent moderate to large benefits in aerobic endurance.

In cell studies, OptiNOs activated mTOR signaling, a pathway that regulates muscle protein synthesis, and increased nitric oxide production in human blood vessel cells.

Flow-mediated dilation, a measure of how well blood vessels widen, was higher than placebo 2 to 3 hours after the first dose of OptiNOs and again at weeks 3 and 6.

No lethal dose of CurQLife Plus was found up to 5,000 mg per kg of body weight, the highest dose tested, in a standard single-dose safety test in rats.

CurQLife Plus lowered MMP-3, an enzyme involved in breaking down collagen, in cartilage cells grown in a lab.

CurQLife Plus lowered TNF-alpha and IL-1beta, two signaling proteins in the inflammatory response, as the concentration rose in cell studies.

CurQLife Plus cut COX enzyme activity in half at 19.9 µg/mL and 5-LOX activity in half at 24.6 µg/mL in a lab assay.

Betaine raised squat repetitions to exhaustion at day 7 and the number of squat repetitions performed at 90 percent or more of peak power at days 7 and 14, but changed nothing in bench press endurance, vertical jump power, bench throw power or Wingate power, fatigue rate and total work.

After 14 days, betaine raised bench throw power, isometric bench press force, isometric squat force and two of four vertical jump power measures against both placebo and pre-supplement values, with no change in squat jump power or in squat and bench press repetitions.

Beta-alanine improved exercise measures more than placebo (median effect size 0.374 versus 0.108), a median gain of 2.85 percent, concentrated in exercise lasting 60 to 240 seconds with no benefit below 60 seconds.

The review reports antioxidant, anti-inflammatory and cholinergic actions for Bacopa monnieri with promising animal data, but finds human results inconsistent across tests and no established optimal dose.

Citrulline malate taken before training added about 3 repetitions to failure, a 6.4 percent increase over placebo, a small effect size of 0.196.

Bacopa takers improved delayed word recall by just over one word and cut Stroop reaction time, while depression scores, combined anxiety scores and heart rate fell in the Bacopa group and rose in the placebo group.

Six weeks of L-citrulline at 8 g or citrulline malate at 12 g raised total upper-body repetitions to failure against placebo and raised post-exercise nitric oxide metabolites, with no gain in maximal strength and no difference between the two forms.

Twelve weeks of Bacopa monnieri, most consistently at 300 mg per day, improved attention and working memory scores, shortened N100 and P300 latencies and lowered plasma acetylcholinesterase activity against placebo.

Across 40 placebo-controlled trials beta-alanine produced a small overall effect size of 0.18 (95% CI 0.08 to 0.28), largest for exercise capacity tests lasting 0.5 to 10 minutes and when taken alongside sodium bicarbonate.

Fourteen days of 400 mg per day soy phosphatidylserine cut time per correct serial subtraction before exercise by 20 percent, from 6.44 seconds to 5.14 seconds, while leaving mood, cortisol and testosterone unchanged.

Ten days of 600 mg per day soy phosphatidylserine lowered peak cortisol by 39 percent and cortisol area under the curve by 35 percent against placebo, and raised the testosterone to cortisol ratio by 184 percent.

Three weeks of 2 g per day L-carnitine L-tartrate blunted exercise-induced rises in purine breakdown markers, malondialdehyde and cytosolic muscle proteins after a squat session, and MRI muscle disruption on carnitine was 41 to 45 percent of the placebo area.

Self-reported motivation showed an increasing trend across the two-week dosing period in the alpha-GPC group and was higher than placebo at night, while anxiety scores did not differ between groups.

Melatonin reduced sleep onset latency by about 7 minutes, increased total sleep time by about 8 minutes and improved sleep quality against placebo.

Both doses raised Stroop total score against placebo (630 mg: 13.0 versus 5.2; 315 mg: 10.8 versus 5.2), while Flanker, N-Back, physical performance and growth hormone showed no group differences.

After controlling for covariates, protein timing showed no difference from control for either strength or muscle growth, and total daily protein intake was the strongest predictor of hypertrophy effect size.

The group recommends at least 1.0 to 1.2 g of protein per kg of body weight daily for people over 65, and more than 1.2 g/kg/day for those who exercise, to help maintain and regain lean mass and physical function.

Deficiency in vitamins A, D, E and K produces recognizable clinical pictures, treatment of a confirmed deficiency requires supplementation alongside a balanced diet, and excess intake can cause hypervitaminosis with serious complications.

Among 223 NCAA Division I athletes, 33.6% had abnormal vitamin D levels, and dark skin tone was the only independent predictor after adjustment (odds ratio 15.2).

Single caffeine doses up to 200 mg and habitual intakes up to 400 mg per day raise no safety concern for healthy non-pregnant adults, 200 mg per day for pregnant women, and the evidence is insufficient to set a safe intake for children and adolescents.

Taking the same vitamin D dose with the largest meal raised mean serum 25(OH)D from 30.5 to 47.2 ng/mL after 2 to 3 months, an average increase of 56.7%.

400 IU or less of vitamin D with calcium did not reduce fractures in the Women's Health Initiative, a pooled analysis found 800 IU daily reduced hip and nonvertebral fracture risk in people over 65, and one annual 500,000 IU dose increased falls by 15% and fractures by 26%.

The Academy concludes that caffeine and other stimulants in energy drinks have no place in the diet of children and adolescents, and that frequent intake of caloric sports drinks raises the risk of overweight, obesity and dental erosion.

Pooled across 13 trials, citrulline lowered post-exercise rating of perceived exertion (effect size 0.81) and muscle soreness at 24 hours (effect size 0.99), with no effect at 72 hours and none on blood lactate.

Turmeric extract at 1,500 mg daily was noninferior to ibuprofen 1,200 mg daily on WOMAC total, pain and function scores at 4 weeks, with fewer reports of abdominal pain or distension (10.8% versus 18.1%).

A narrative review for clinicians on magnesium status, intake and testing, estimating that 56 to 68 percent of Americans do not reach the recommended daily allowance.

Against placebo, 500 mg of elemental magnesium daily for 8 weeks increased sleep time and sleep efficiency and lowered Insomnia Severity Index scores by 2.38 points.

Total body bone mineral content reached a plateau about six years past peak height velocity, roughly age 18 in girls and 20 in boys, and 39% of adult total body bone mineral was laid down in the four years around puberty.

Whole brain atrophy averaged 0.76% per year on B vitamins compared with 1.08% per year on placebo, and among participants whose baseline homocysteine was above 13 micromoles per liter the rate of atrophy was 53% lower on treatment.

Iron deficiency with and without anemia is widespread in females, and the authors recommend treatment when ferritin is below 50 micrograms per liter in pregnancy, below 30 in other adults and below 20 in children, with oral iron first line.

Evidence for probiotics across women's health is uneven: several outcomes, including preterm birth, were null, and the authors say the best strains and doses are not yet established.

Calcium supplements taken without vitamin D were associated with a higher rate of myocardial infarction, hazard ratio 1.31 (95% CI 1.02 to 1.67) in patient level data.

Tissue NAD+ levels fell with age in both males and females, while DNA damage and PARP activity rose with age, and PARP activity was inversely related to NAD+ levels.

Across 15 studies, conclusions about DHA and specific cognitive tests were not consistent, though studies of brain activity reported benefits and over half of the studies reported a favorable role for DHA in at least one area of cognition or behavior.

Ascorbic acid is the most efficient enhancer of non-heme iron absorption, needing a molar ratio of about 2:1 ascorbic acid to iron for meals with low to medium absorption inhibitors and above 4:1 for high inhibitor meals.

In this observational study of 4,807 Dutch adults aged 55 and over, those eating the most dietary menaquinone had a lower rate of coronary heart disease death than those eating the least (relative risk 0.43, 95% CI 0.24 to 0.77). No supplement was tested.