The aim of this assignment is to understand the parameters of the experiment conducted in the journal article and to assess the effectiveness of the experiment, the results, and presence or absence of bias. Over time it has been well established that a healthy and nutritiously balanced diet plays a vital role in overall well-being and health. Among a range of different diets gaining popularity, the Mediterranean diet is a new favourite. The primary aim of this study was to identify the extent to which Mediterranean diet adherence influences cognitive performance and mood. Pervious research attempts have already proved biological effects of Mediterranean diet expressed in improved physiological condition, however, influence on cognitive performance and mood were not investigated thoroughly.
The Mediterranean diet consists of consuming fatty fish, fruits and vegetables, olive oil, legumes and whole grains. This diet provides nutrients that support brain function such as, magnesium, essential fatty acids, proteins, vitamins (especially Vitamin E and C) and antioxidants. According to McMillan (2010), “There have been a number of Mediterranean diet intervention studies demonstrating improvements in endothelial cell function, inflammation and insulin resistance stroke and cardiovascular outcomes and in rheumatoid arthritis.” (p. 1) But when it comes to studies on the benefits of diet on mental functioning, the research is mostly made up of supplementation studies or studies involving increased intake of one food source or nutrient. This particular experiment explores the effect of an entire dietary change (namely, the Mediterranean diet) on mood changes and cognitive function in healthy participants. Most of the research on this topic was based on epidemiological studies till date which have shown results such as reduced age-related cognitive decline and lower risk of developing dementia. A recent study was conducted in 2009 on the effects of diet on cognitive functioning which revealed that various diet regimens differentially impact cognitive behaviour. Further studies have also shown that increase in magnesium and essential fatty acids may improve anxiety and depression.
This experiment was a single-blind, randomised, parallel group trial consisting of 25 young females randomly divided into the No Change (NC) control group and the Diet Change (DC) group. The study was conducted for a period of 10 days, during which various mood and cognitive ability assessing tests were given to participants on the day they started the experiment (Day 1) and then on the last day of the experiment (Day 10). Participants in the DC group had to adhere to a strict nutrient dense Mediterranean diet (there was no calorie restriction) while participants in the control group (NC) had to tend to endure their customary day-to-day nourishment habits. Both groups were instructed to keep a food diary.
The tests conducted were the 65-item Profile of Mood States (POMS) questionnaire, which measures six mood dimensions (downheartedness, anger, apprehension, exhaustion, dynamism, and confusion), the Bond and Lader Visual Analogue Scales (VAS) which derives three mood factors: ‘Alert’, ‘Calm’ and ‘Content’. The Computerised Mental Performance Assessment (COMPASS) test was conducted to measure variations in intellectual function such as working memory, consideration, long term reminiscence and managerial utility. (McMillan, 2010) The results showed that while there was no significant difference in the two groups’ waist size and baseline weight, associated with the NC group, the DC group displayed measurable developments in self-rated vigour, alertness, and feelings of satisfaction. But changes in cognitive tasks were slightly unpredictable (McMillan, 2010). This depicts that although the Mediterranean nourishment approach has a constructive effect on temper features, the special effects on intellectual purpose were limited to reaction time variables. For example, for tasks of numeric operational memory and expression recollection, it showed that response period became better in the control group and not in the DC group (McMillan, 2010). The cause for this discrepancy is not clear but it reflects time differences and a possible artefact of practice effects. One of the most important findings was highly significant improvement in reaction times on spatial memory in the DC group. This shows that eating routine helps with managing long haul consideration. Another important result was observed on self-reported mood measures despite the study being as short as 10 days which shows consistent mood effects. These improvements could be attributed to the increase in consumption of Omega-3 and magnesium. The mean scores for POMS showed an improvement in the DC group, with individuals of this group showing decreased scores of total mood disturbance.
These results show that while having a nutrient rich diet may have directly improved their cognitive function and mood, non dietary factors could also have contributed. For example, although the participants were not explicitly told about the Mediterranean diet, it is possible that participants of the DC group could have surmised that their diet was healthier which led to expectations of well-being, which in turn could have had an effect of the direct or indirect nature on their temper level. In the same way, this could have led to worse mood in the NC group. Thus, it is paramount to investigate what found a true switch-group within a study which would be similar to this one. Moreover, the research was conducted on a comparatively less number of participants and over the course of only 10 days. Replication with larger sample pool and over an extended period of time could aid in comprehending the impending applications of nourishment to intellectual enactment, which would not only benefit the public for conventional reasons but it could also probably supplement conventional treatments for mood dysfunction.