This study explored stress & food preferences. 232 Flemish students completed a food frequency questionnaire and psychological tests to measure stress levels, during exam period, to determine effects of stress on food choices as part of a longitudinal study.

Results

Diet quality of the students was observed to deteriorate during the exam period in response to stress, with preferences for high fat and sugar foods increased. The study indicated that chronic stress alters food preferences to high fat and high sugar foods. However, the data was from food frequency questionnaires and self reported measures of stress levels. These methods are vulnerable to self reporting biases. Further research which monitors diet whilst taking serum samples of cortisol and other stress-related markers are required to explore these findings further.

Abstract available here

Michels, N., Man, T., Vinck, B., & Verbeyst, L. (2020). Dietary changes and its psychosocial moderators during the university examination period. European journal of nutrition, 59(1), 273–286.

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Dr Wendy Suzuki – The Brain Changing Benefits of Exercise (TED).

This study investigate bilingualism & cognition. The study was a meta analysis of studies. Inclusion criteria was studies investigating bilingualism in the elderly with relation to Alzheimer’s disease risk. 6 prospective cohort studies were selected and 8 retrospective studies were selected. Of the 14 studies, only 2 had a monolingual control group. 14 studies selected for analysis. Study indicated that bilingualism may be protective against memory decline in older adults.

Results:

Meta analysis indicates that one exception, the studies support the idea that bilingualism reduces risk of memory decline. . However, only a small sample of studies included, although selected studies generally of a good sample size (>500). Only two of the studies included participants with Alzheimer’s disease diagnosis. Moreover, only two studies had a control group. Further, two of the studies included only Hispanic subjects, which may have impacted results.

A notable limitation of the meta analysis is that it did not include any statistical analysis methods (i.e p value) and this is a significant limitation. Further large scale research is required to explore effects of bilingualism on cognition, and whether bilingualism may be protective against cognitive decline.

Abstract available here

Klimova, B., Valis, M., and Kuca, K. (2017). Bilingualism as a strategy to delay the onset of Alzheimer’s disease. Clin. Interv. Aging 12, 1731–1737.

This study investigated bilingualism & cognition. Study included 28 older adult participants – 14 monolingual participants and 14 bilingual participants (who had been bilingual since before age 11). All participants were subjected to a fMRI and had no diagnosed mental health conditions.

Results indicated:

Bilingual participants performed better on tasks and had better working memory (p<0.01) and better connectivity (p=0.002), compared with the monolingual group (p=0.17)

Results observed for other types of memory were not significant

Study size was small. Further large scale warranted. Study did not specify regarding bilingualism, as to whether participants spoke more than 2 languages, or whether certain type and complexity of language afford greater protection (i.e romance languages, Germanic languages etc.). Further research merited to explore effects of bilingualism on other types of memory.

Abstract available here

Grady, C. L., Luk, G., Craik, F. I., and Bialystok, E. (2015). Brain network activity in monolingual and bilingual older adults. Neuropsychologia 66, 170–181. doi: 10.1016/j.neuropsychologia.2014.10.042

In this study memory change over 6 years was assessed using a large scale sample (16, 638 elderly individuals born <1948) from Health and Retirement Study. Growth curve models were analysed with reference to memory recall of a 10 word list and levels of social integration (i.e with family, volunteering, marital status).

Results indicated:

Socialisation demonstrated as a predictor of slower memory decline (p<.01). 

In individuals with vascular disease, socialisation observed to be protective buffer ( (p< 0.05)

Memory amongst least socialised deteriorated at twice the rate of other participants, with association greatest amongst those with <12 years of education (p<0.07)

The study indicates that socialisation and levels of education may be protective factors for memory decline. The study also suggests that socialisation may reduce risk for memory decline in individuals with vascular diseases. The study did not use a robust means of measuring memory capability, such as MMSE. Results for socialisation as a predictor of slower memory decline not statistically significant. However, socialisation in individuals with vascular disease as a protective factor was observed to be statistically significant. More research required as to the mechanisms of how socialisation reduces risk of memory decline in vascular disease. Findings for education as a protective factor were observed to be statistically significant. More research required into to what level of education is most protective against memory decline.

Abstract can be viewed here

Ertel, K. A., Glymour, M. M., & Berkman, L. F. (2008). Effects of social integration on preserving memory function in a nationally representative US elderly population. American journal of public health, 98(7), 1215–1220.

This study explored fasting & cognitive performance. It identified that biological ageing is a process which is accelerated and exacerbated by excessive calories and a sedentary lifestyle. Further, these factors combined may increase the risk of developing neurodegenerative diseases. This systematic review explored the role of different types of IF (intermittent fasting) on cognitive function, with specific focus on BDNF (brain derived neurotrophic factor) as a marker. Reduction of levels of BDNF has been associated with cognitive decline and increased risk of Alzheimer’s disease. Moreover, reductions in BDNF may result in a reduction in synaptic plasticity, memory and learning.

The study accepted and appraised 82 papers. Key findings were:

IF modulated BDNF supporting synaptic maturation and function

Primary evidence demonstrates pro-cognitive and neuroprotective effects of IF and BDNF

Sex specific differences were observed in response to IF

IF was suggested to be supportive for brain health and sustaining cognitive performance into old age, although it was identified further research is required into this area

The abstract is available here:

Seidler, K., & Barrow, M. (2021). Intermittent fasting and cognitive performance – Targeting BDNF as potential strategy to optimise brain health. Frontiers in neuroendocrinology, 65, 100971. Advance online publication. https://doi.org/10.1016/j.yfrne.2021.100971