No effect of n-3 long-chain polyunsaturated fatty acid (EPA and DHA) supplementation on depressed mood and cognitive function: a randomised controlled trial – reply by Rogers et al

Neurobehavioral Effects of Consuming Dietary Fatty Acids

BACKGROUND

Research results on the neurobehavioral effects of consuming dietary fatty acids are mixed. Therefore, this study examined the effects of consuming dietary fatty acids on depression, mood, and anxiety.

METHODS

In this randomized crossover-design study, 37 university students served as their own controls, consuming each of the following diets for a 4-day period with a 2-week washout period between diets: (1) low fatty acid, (2) high saturated fatty acid (SFA), (3) high polyunsaturated fatty acid (PUFA), and (4) control. The order of sessions was counterbalanced across dietary groups. Following consumption of each diet, participants were examined for within-subject differences in depression, mood, and anxiety. Measures included weighed dietary fat intakes, Zung's Self-Rating Anxiety and Depression Scales, and the Positive and Negative Affect Schedule.

RESULTS

Participants had significantly higher positive affect scores (p < .007) and were significantly less irritable (p < .04) when they consumed diets rich in SFAs and PUFAs than when they consumed a low fatty acid or control diet. However, depression, anxiety, and negative affect scores did not differ significantly among diets. Analysis of participants' serum lipid levels following their intake of the fatty acid and control diets indicated significantly higher levels of total cholesterol (p = .006) and serum triglycerides (p = .003) with the control diet.

CONCLUSIONS

These results highlight the neurobehavioral benefits of consuming dietary fatty acids among healthy individuals. By concentrating on the positive effects of diet on affective processes, health professionals can also provide support for at-risk individuals.

Effect of low dose ω-3 poly unsaturated fatty acids on cognitive status among older people: a double-blind randomized placebo-controlled study

Background

Cognitive impairment is a prevalent health problem in older people and its global prevalence tends to increase parallel to the extended life expectancy in world. The beneficial effect of ω-3 PUFAs on cognitive impairment has been demonstrated in some experimental and cohort studies. In this study we aimed to assess the effect of low dose docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) supplementation on cognitive status in the elderly.

Methods

In a double-blind, randomized placebo-controlled study, 199 individuals aged ≥65 years with normal or mild to moderate cognition impairment were assigned to receive either 180 mg of DHA plus 120 mg of EPA or placebo for 180 days. Cognitive status was assessed using Mini-Mental State Examination (MMSE) and Abbreviated Mental Test (AMT) score.

Results

MMSE and AMT scores were not different at the time of allocation [18.84 (5.37), 18.55 (5.12), (P = 0.70) and 4.81 (2.79) and 4.64 (2.77), (P = 0.67) respectively] and over 6 months between the ω-3 PUFA- and placebo- treated groups [18.57 (5.21), 18.39 (5.10), (P = 0.80) and 4.64 (2.77) and 4.48 (2.69) and (P = 0.67)]. The participants were categorized based on MMSE score into normal cognition, mild and moderate cognitive impairment. After multivariate adjustment, there was no significant difference among categorized groups regarding the ω-3 PUFA effect except in normal cognition group, that amount of decline in AMT in ω-3 poly unsaturated fatty acids (PUFAs) was less than placebo group.

Conclusions

It seems that prescription of low dose ω-3 PUFAs for 6 months had no significant beneficial effects on improvement of cognition or prevention of cognitive decline in older people.

Preventive or potential therapeutic value of nutraceuticals against ionizing radiation-induced oxidative stress in exposed subjects and frequent fliers

Humans are constantly exposed to ionizing radiation deriving from outer space sources or activities related to medical care. Absorption of ionizing radiation doses over a prolonged period of time can result in oxidative damage and cellular dysfunction inducing several diseases, especially in ageing subjects. In this report, we analyze the effects of ionizing radiation, particularly at low doses, in relation to a variety of human pathologies, including cancer, and cardiovascular and retinal diseases. We discuss scientific data in support of protection strategies by safe antioxidant formulations that can provide preventive or potential therapeutic value in response to long-term diseases that may develop following exposure.