A Systematic Review of the Effect of Dietary Supplements on Cognitive Performance in Healthy Young Adults and Military Personnel.

Intake of dietary supplements has increased, despite evidence that some of these have adverse side effects and uncertainty about their effectiveness. This systematic review examined the evidence for the cognitive benefits of a wide range of dietary supplements in healthy young adult samples; the aim was to identify if any might be useful for optimising cognitive performance during deployment in military personnel. Searches were conducted in 9 databases and 13 grey literature repositories for relevant studies published between January 2000 and June 2017. Eligible studies recruited healthy young adults (18-35 years), administered a legal dietary supplement, included a comparison control group, and assessed cognitive outcome(s). Thirty-seven of 394 identified studies met inclusion criteria and were included for synthesis. Most research was deemed of low quality (72.97%; SIGN50 guidelines), highlighting the need for sound empirical research in this area. Nonetheless, we suggest that tyrosine or caffeine could be used in healthy young adults in a military context to enhance cognitive performance when personnel are sleep-deprived. Caffeine also has the potential benefit of improving vigilance and attention during sustained operations offering little opportunity for sleep. Inconsistent findings and methodological limitations preclude firm recommendations about the use of other specific dietary supplements.

Lyprinol only partially improves indicators of small intestinal integrity in a rat model of 5-fluorouracil-induced mucositis.

BACKGROUND: Intestinal mucositis is a common and debilitating side-effect of chemotherapy, associated with severe small intestinal inflammation. Marine oils, such as Lyprinol, a lipid extract derived from New Zealand Green-lipped Mussels, rich in long-chain omega-3 polyunsaturated fatty acids (n-3 PUFA), have demonstrated therapeutic potential for the treatment of inflammatory conditions. We assessed the effects of Lyprinol on the severity of 5-fluorouracil (5-FU)-induced mucositis in female Dark Agouti rats. RESULTS: Small intestinal weight was significantly greater in rats treated with 5-FU+HDL, 5-FU+LDL and 5-FU+FO compared to 5-FU-treated controls (p < 0.05). Myeloperoxidase activity in the proximal and mid small intestine were significantly lower in 5-FU+OO-treated rats compared to 5-FU+vehicle-treated controls (p < 0.05). Histological damage severity was elevated in 5-FU+vehicle, 5-FU+OO and 5-FU+FO-treated rats compared to saline-treated controls, but not in rats treated with 5-FU+HDL or 5-FU+LDL. SBT results and biochemically-assessed sucrase activity were lower in all 5-FU-treated rats compared to saline-treated controls. 5-FU+HDL treated animals had significantly longer crypts and increased proliferation in the mid small intestine compared to 5-FU+vehicle rats (p < 0.05). CONCLUSION: Lyprinol treatment in rats with 5-FU-induced mucositis only minimally decreased indicators of intestinal integrity. Further studies of marine oils high in omega-3 PUFA content are warranted for the potential prophylactic treatment of intestinal mucositis. METHODS: Rats were allocated to six groups (n = 8/group); Saline+vehicle, 5-FU+vehicle, 5-FU+high-dose Lyprinol (5-FU+HDL), 5-FU+low-dose Lyprinol (5-FU+LDL), 5-FU+olive oil (5-FU+OO), and 5-FU+fish oil (5-FU+FO). Treatments were administered via oro-gastric gavage from days 0-7. Mucositis was induced on day 5 by 5-FU injection (150mg/kg i.p.). (13)C-sucrose breath tests (SBT) were conducted on days 0, 5 and 8 to assess small intestinal function. Rats were sacrificed on day 8 and small intestinal tissues collected for histological and biochemical analysis.