- Lifestyle Choices and Brain Health
- Brain Health and Mental Well-Being
- The Brain-Body Connection
- Cognitively Stimulating Activities
- The Brain-Sleep Connection
- Social Activities for Healthy Aging
- The Importance of Social Engagement for Older Adults
- 9 Ways to Promote Social Activities for Seniors
- Social engagement and cognitive function among middle-aged and older adults: gender-specific findings from the Korean longitudinal study of aging (2008–2018)
- Dependent variable: cognitive function
- Independent variable: a change in social engagement
- Statistical analysis
- Ethics declaration
Lifestyle Choices and Brain Health
This article is largely the recommendations of the AARP's Global Council on Brain Health (GCBH) (1–6). The AARP is a United States-based interest group whose stated mission is “to empower people to choose how they live as they age”. According to the organization, it had more than 38 million members as of 2018 (7).
The article aims to provide an overview of the evidence from current literature and expert opinion on key issues known to be relevant in preserving brain health as people age. The GCBH is an independent group of scientists, health professionals, scholars, and policy experts from around the world working in areas of brain health related to human cognition.
The GCBH is convened by the AARP in collaboration with Age UK. It follows a structured process for generating reliable information, which includes conducting extensive literature reviews and holding GCBH member meetings to discuss lifestyle issue areas that may impact brain health as people age.
The goal of the group is to provide specific, evidence-based recommendations for people to consider incorporating into their lives to maintain and improve brain health as they age. The issues discussed here reflect the priorities established by the GCBH. We acknowledge that other entities may disagree on the relevance of the topics presented here.
The recommendations included within this review are related to mental well-being, exercise, cognitively stimulating activities, sleep, nutrition, and social connectedness. Professionals and consumers are constantly overwhelmed with contradictory information about changes in lifestyle that can impact brain health.
The AARP created the GCBH to evaluate the evidence that emerges and provide the professional and the lay consumer with accurate and scientifically valid information to guide the lifestyle choices they make to improve their brain health. Therefore, the goal of this paper is to summarize these recommendations for professionals.
Brain Health and Mental Well-Being
The goal of this section is to explore the relationship between mental well-being and brain health. Mental well-being, for the purpose of this article, is defined as experiences characterized by feeling good, functioning well, and adequately coping with life circumstances and challenges.
The GCBH's interest in this topic was triggered by the results of the 2018 AARP Brain Health and Mental Well-Being Survey. The survey was performed on 2,287 randomly selected, community dwelling adults in the USA.
The subgroup age over 50 (N = 1,263) was analyzed to better understand the relationship between mental well-being and brain health in this group.
It was found that people who scored higher on the scale of mental well-being tended to report better memory and thinking skills than those who reported lower mental well-being.
Furthermore, the AARP found that when a subject rated their episodic memory and executive function as excellent or very good, they also reported very high rates of mental well-being. Comparatively, those who rated the same functions as average, fair, or poor reported low rates of mental well-being.
Interestingly, the largest difference shown was in how people rated their mental sharpness. Those who rated themselves as having low mental sharpness reported a nearly 17-point difference (38.8 compared to 55.5) in mental well-being from those who said their mental sharpness was excellent or very good (8). the results of this survey, we hypothesize that there is a positive correlation between mental well-being and brain health.
Our literature search shows many scientific studies that explore the same hypothesis. For example, Sutin, Stephan, and Terracciano (9) evaluated the roles of optimism and life purpose in brain health.
They found that greater optimism, positive attitude, positive affect, life satisfaction, and purpose in life were associated with reduced risk of dementia.
When this data was combined with socioeconomic, psychological, and generational variables, they discovered that a sense of a purpose in life was one of the strongest predictors of better brain health.
Furthermore, the study found that having a purpose in life was associated with a 20% reduction in dementia risk. An additional study conducted by Galderisi et al. corroborated these findings and suggested that a meaningful and goal-driven life also reduces the risk of dementia (10).
If it's agreed that mental well-being contributes to brain health, then we should explore which lifestyle choices have an effect on mental well-being.
For example, as we discuss later in the section titled “The Brain and Social Connectedness,” individuals with strong community links have been associated with both mental well-being and better brain health when compared with the control group (11, 12).
The same is true for exercise, which is addressed in “The Brain-Body Connection” portion of this review (13–21).
The opposite also appears to be true. Research has shown that early-life stress influences mental well-being and the brain. Significant adverse events early in life can render people vulnerable to mental illness later in life (22).
Even during the time of gestation, exposure to excessive levels of cortisone resulting from high levels of stress can have long lasting effects by influencing brain development, subsequently lowering future levels of mental well-being (23–27).
For example, researchers have specifically evaluated the effects of early-life adversity (28–32). The research showed a reduction of brain regions responsible for cognition, such as the hippocampus, in individuals that were exposed to early-life adversity (33, 34).
Furthermore, the potential relationship between negative early-life experiences and the presence of amyloid (the basic lesion observed in Alzheimer's Disease) has been suggested in several animal studies including mouse models of Alzheimer's Disease (35).
Research shows that as we age, we are exposed to both physical and emotional losses. However, despite the increase in incidences associated with loss, getting older does not necessarily mean experiencing less happiness.
People who manage stress effectively most or all of the time report greater well-being as they pass through later stages of life after the age of 50 (36).
In addition, it should be considered that the way that individuals successfully manage stress is affected by cultural perceptions, social-economic status, family structure, and environment (11, 37, 38).
A final pertinent factor to consider is the relationship between severe depression and dementia risk. It has been discovered that individuals who have normal memory but suffer from severe depression are ly to develop dementia within a few years (39).
Memory loss symptoms caused by Alzheimer's and other related diseases may not manifest themselves for up to 15–20 years after the disease has begun to develop (40).
Because of this, it is important to acknowledge the possibility that late-life depression could be the only early manifestation of Alzheimer's disease in a given individual.
In summary, research shows that mental well-being appears to be strongly associated with brain health and could potentially be a protective factor in the onset of neurodegenerative disorders.
The Brain-Body Connection
For many years, clinicians have recommended physical activity under the belief that it will have a positive impact on brain health no matter if it results from having a physically active lifestyle (walking to work or the store in place of driving, taking the stairs, and engaging in hobbies and sports) or from purposeful exercise (brisk walking, strength training, and aerobic training).
Current research strongly supports this belief. By analyzing animal studies, scientists were able to determine that exercise facilitates neuroplasticity and improves learning outcomes (17, 18). The same seems to be true for humans.
Coelho found that physical exercise effectively increases the peripheral levels of brain-derived neurotrophic factor (BDNF), a protein in the brain that promotes growth and maintenance of neurons in the elderly (15). Furthermore, Baker et al.
conducted a randomized trial comparing both high-intensity aerobic exercise and stretching to stretching alone over 6 months (14).
The results showed the sex-specific effects of aerobic exercise on cognition, glucose metabolism, and hypothalamic-pituitary-adrenal axis and trophic activity as well as comparable improvements in cardiorespiratory fitness and body fat reduction. Interestingly, different results were observed in women and men.
For women, aerobic exercise enhanced performance on multiple tests. Their results showed improved executive function while increasing glucose disposal during the metabolic clamp and reducing fasting plasma levels of insulin, cortisol, and BDNF. For men, aerobic exercise increased plasma levels of insulin- growth factor 1, but only had a favorable effect on a single measure of performance (17).
Other studies have focused on demonstrating the neurological correlations between aerobic exercise and brain health (41). For example, a study by Colcombe et al.
examined whether aerobic fitness training in older adults can increase brain volume in regions associated with age-related decline in both brain structure and cognition.
They found a significant increase in both gray and white matter regions of the brain in those who participated in the aerobic fitness training but not in the older adults who participated in the stretching and toning (non-aerobic) control group (17).
Finally, several meta-analyses have confirmed the role of exercise in brain health. These studies documented a significantly reduced risk of dementia and mild cognitive impairment associated with midlife exercise (13, 16, 18–21, 42–45).
While not all studies relating physical activity to brain heath have showed corresponding results (46), the GCBH felt that the evidence was strong enough to support a recommendation consistent with those from the American Heart Association of 150 min of moderate-intensity aerobic exercise and 2 or more days a week of moderate-intensity weight training (47).
Cognitively Stimulating Activities
Cognitively stimulating activities are defined as mentally engaging activities or exercises that challenge a person's ability to think and process information. These include mind-teaser games, educational activities, intellectual inquiries, and mental challenges.
It has been well-established that brain structures and functions change as an individual ages (48). These changes, however, are not universal.
Some individuals at the age of 80 have the same volume of certain brain structures associated with cognitive function, such as the hippocampus, as they did in their 30s. Others show substantial volume loss (49). The challenge is to understand which factors are responsible for these important differences.
Education and learning have been known to enhance cognitive reserves, making an individual less susceptible to the effects of age or disease-related brain changes (50).
Research has shown that brain plasticity continues to be present through the aging process; therefore, we can hypothesize that cognitively stimulating activities could help maintain cognitive function or delay cognitive decline (51, 52). Supporting this hypothesis, several studies have established a link between participation in self-initiated, cognitively stimulating activities and brain health (53–59).
Unfortunately, this hypothesis still has yet to be demonstrated. The National Academies committee concluded that the “AHRQ (U.S.
Agency for Healthcare Research and Quality) systematic review identified no specific interventions to justify mounting an assertive public health campaign to encourage people to adopt them for the purpose of preventing cognitive decline and dementia” (60). This includes performing what can be described as cognitively stimulating activities.
In conclusion, although there is a large body of evidence suggesting that cognitive training can improve reasoning, memory, and speed of processing, the validity of these connections has yet to be documented in large randomized control trials. It is important to note that no specific “brain game” or “brain exercise” has shown to be effective on brain health.
The Brain-Sleep Connection
Sleep patterns change during the aging process, with both the sleep structure and duration becoming significantly altered (61). Even though sleep patterns vary substantially between age 25 and 50, the need for sleep does not differ.
Recent literature has shown that most adults require between 7 and 8 h of sleep a night to main good physical and brain health (62). Some of the major changes observed are related to depth of sleep and continuity of sleeping patterns.
While most older adults experience no changes in the length of time it takes them to fall asleep, interruption of sleep during the night and early wakening are common. Additionally, older adults also tend to wake up earlier in the morning and find that staying up late becomes more difficult.
These changes are a normal part of the aging process and do not affect brain health. However, decreased total sleep time does indeed cause negative effects (9, 63–65).
In the AARP 2016 Sleep and Brain Health Survey, it was found that 44% of adults 50 years of age or older rated their quality of sleep as extremely good or very good; 84% said they were mostly well-rested in the morning; but only 33% reported being very satisfied with the amount of sleep they got daily (65).
The 2016 AARP survey also discovered that while over half (56%) of adults 50 and older reported that they wake up at about the same time every morning, less than a half (48%) go to bed at same time and only a third (33%) report getting 7–8 h of sleep at night.
Researchers have found that attention memory and executive function can be negatively affected by getting
Social Activities for Healthy Aging
While nutrition and exercise play a massive role in ensuring healthy aging, so does social engagement. Interacting with others has been clinically proven to keep our brains engaged and also enhance our mood. Research continues to show that, for seniors, social engagement leads to better physical health and reduces the risk of cognitive decline.
Geriatric medical specialists agree that social activity can help older adults improve their mental health while improving memory functions. Staying socially engaged can also reduce depression and create an overall higher quality of life for your loved one.
“Use it or lose it” is an old phrase that happens to be true. If you don’t exercise your brain, it will atrophy just your body’s muscles do without exercise. Socializing is an excellent workout for your brain, keeping it supple, alert and active.
The Importance of Social Engagement for Older Adults
Research has proven that social isolation can put seniors at greater risk. It can even lead to a greater risk of physical illness and accidents in the home.
Social interaction stimulates a hormone called oxytocin. If you want to impress people, you can explain that oxytocin is one of many neuropeptides that can generate good feelings. Often referred to as the “love hormone,” social bonding triggers the release of oxytocin. Just as endorphins can kick in with exercise, the oxytocin kicks in with social interaction.
Social activity also provides a mental workout to keep our brain engaged. Conversation requires listening, reasoning, attention, language skills, and mental processing that help keep cognitive and memory skills tuned and operational.
Social interaction and connecting with others can also boost an older adult’s mood by improving energy levels and sense of self-worth. Your loved one may need to feel that they are heard and appreciated.
As we age, we often feel we’ve become “invisible” no matter how successful and recognized we might have been in earlier life. We live in a society that overlooks our elderly population no matter how accomplished they may be.
Social interaction can help counter the risk of depression and feelings of low self-esteem.
Even before the COVID-19 global pandemic arrived, experts knew that loneliness and isolation could have a negative impact on our mental health, especially for seniors. Longtime friends move away or pass away.
We move away from long-time homes to down-size. As children and grandchildren grow and move away, families may become widespread. Mobility and/or hearing issues may also make socializing more of a challenge.
It’s easy to socially isolate and not realize the consequences until it’s too late.
9 Ways to Promote Social Activities for Seniors
Even in extreme circumstances during a worldwide health crisis – shelter in place orders and social distancing – there are many ways for everyone, including older adults, to stay socially engaged.
- Utilize online communication. Help seniors use technology such as FaceTime and Zoom. Technology today allows us to be in constant contact with family and friends, whether near or far. Not only can we hear them, but we can also see them and experience the environment that surrounds them.
- Online games. In addition to phone calls, chat rooms, and email messages, there are dozens of games to play online with others. “Words with Friends” is a popular version of online Scrabble, but there are many others, including interactive card games. While this doesn’t provide “live” social engagement, it provides connection with others and has the dual benefit of keeping the brain’s cognitive skills sharp.
- Group activities. Book clubs, wine-tastings, cooking classes are also going virtual. All of these offer “distance” learning and social interaction that can help keep our minds honed.
- Exercise classes. Group exercise, Tai-Chi, and yoga classes are also available online. They should be encouraged as they include a social element and are a great way to keep your body and mind activated.
As we ease back into normalcy post-pandemic, there are even more ways seniors can stay social and engaged, ensuring healthy longevity. Here are a few other social activities for older adults that may be available with a few restrictions:
- Enroll in a class. Whether it’s at a local college or a course offered by a recreation center or senior organization, there are usually many local adult education classes available. You can learn a new skill (playing guitar) or hone an existing skill (speaking a foreign language).
- Join others for outdoor activities. Get outdoors into the fresh air together — walking, hiking, birdwatching.
- Get involved or volunteer with local organizations. Again, there are ly many options: your church, local animal shelter, the library, elementary schools.
- Follow your passion. Do something you love but do it with others. Knitting, crafting, woodworking, or painting? Put together a group of people who share your interest and do it together from a distance!
We don’t want to lose “social capital” as we age. Being a “social senior” clearly has long-term health benefits. Make an effort to stay in touch with family, friends, neighbors, and colleagues. Connect socially with others, whether in person or remotely, via the many different virtual tools available today.
Keeping Socially Engaged is Good for your Health
Social Engagement Promotes Brain Health
Social engagement and cognitive function among middle-aged and older adults: gender-specific findings from the Korean longitudinal study of aging (2008–2018)
Social engagement and cognitive function among middle-aged and older adults: gender-specific findings from the Korean longitudinal study of aging (2008–2018)
Recent findings suggest that social disengagement in later life may result in cognitive decline and increase risk of Alzheimer’s and related dementias.
However, little is known regarding the gender-specific longitudinal association between social engagement and cognition among middle-aged and older adults. Using data from a nationally representative sample of 2707 men and 5196 women from the Korean longitudinal study of aging, we examined the gender-specific association between social activity and cognitive function.
Results from the generalized estimating equation model showed that compared to individuals with consistent social engagement (religious, senior center, sport, reunion, voluntary, political), individuals with inconsistent engagement had lower cognitive function. Transitioning from engagement to non-engagement was associated with lower cognitive function among men only.
Not being part of a senior center was associated with decreased cognitive function among both genders, while not being part of a religious group was significant for women only. While marital status was a significant predictor of cognitive ability for women, depression was a significant predictor for men.
These findings have implications for policy-makers as interventions targeting improved cognitive function among middle-aged and older adults may be more effective when gender-specific predictors are taken into consideration.
Alzheimer’s disease and related dementias are a group of conditions associated with the decline in an individual’s ability to perform daily activities, primarily in later life1.
In 2020, it was estimate that more than 50 million people worldwide live with dementia, and that this number will increase three-fold by 2050 with population aging2,3.
Scholars believe that related societal costs will exceed 1% of global gross domestic product (GDP), equivalent to $818 billion (US dollar) annually3.
In South Korea, the proportion of older adults with dementia increases by around 27% each year, which is much higher than the global average of 17%4. As one of the most rapidly aging societies in the world, this figure is predicted to increase as South Korea becomes a “super-aged society” by 2029, whereby more than 20% of the population consists of older adults5.
To date, twelve potentially modifiable risk factors are considered to trigger neuropathological developments across the life course and account for 40% of all dementia cases: (1) less education, (2) hypertension, (3) hearing impairment, (4) smoking, (5) excessive drinking, (6) obesity, (7) depression, (8) physical inactivity, (9) air pollution, (10) traumatic brain injury, (11) diabetes, and (12) low social contact6,7.
On the other hand, consistent participation in religious activities, friendship groups, leisure/sports clubs, and/or frequent face-to-face contact with one’s children have been associated with cognitive improvement, even when activities of daily living (ADL), instrumental activities of daily living (IADL), and presence of chronic illnesses are controlled for8. Thus, interactions with others have been employed in various interventions to enhance cognitive reserve or resilience, and thereby prevent or delay the incidence of dementia7. For example, in a longitudinal study of Japanese community-dwelling older adults, individuals encouraged to engage in daily conversations with friends/relatives had 0.56 times decreased risk of dementia than their counterparts9. In the China Health and Retirement Longitudinal Study, those who cared for their grandchildren or participated in voluntary activities also had decreased risk of dementia incidence10.
Surprisingly, despite ample evidence regarding the association between social engagement and cognitive function, few studies have focused on gender differences between men and women with cognitive decline7. Furthermore, existing studies on this topic have been inconsistent.
For example, in an American sample of non-demented, community-dwelling older adults, social support was associated with cognitive decline among men only11. Contrastingly, in a Japanese longitudinal study of community-dwelling older adults, social participation was associated with cognitive decline among women only12.
However, it is challenging to identify key factors that drive the inconsistent findings limited number of studies available.
Among Asian populations, researchers have suggested that cognitive ability among older adults differ dramatically by gender, especially among cultures where more educational or economic opportunities were given to boys than girls in the past13.
Considering South Korea’s deep-rooted history of son preference and patrilineality14, we presumed that gender-specific differences would also emerge among middle-aged and older adults in our study.
Thus, this study employed the Korean longitudinal study of aging (KLoSA), a large, nationally representative, longitudinal study of community-dwelling Korean adults, to investigate the association between social engagement and cognitive function, according to gender.
This study employed KLoSA data ranging from 2008 to 2018. The KLoSA is an on-going, biennial panel survey which has been conducted every two years by the Korean Employment Insurance Fund of the Ministry of Labor, following Korea’s transition to an aging society in the year 200015.
The primary purpose of the study is to examine the demographics, family relationships, health status, health utilization behaviors, employment status, and financial power of middle-aged and older Korean adults over time. The survey sample consists of approximately 10,000 adults over the age of 45, who reside in South Korea (excluding Jeju Island).
In 2006, the KLoSA selected 6171 baseline households multistage stratified sampling by geographical region (according to the South Korean national census) and household type (apartment/house).
For the survey, computer assisted personal interviewing (CAPI) techniques were employed to trace the characteristics of baseline participants over time, which allowed for automatic calculation and scoring of cognition-related questions. Detailed information about the study is available on the KLoSA website (http://survey.keis.or.kr).
In our study, we included all individuals over the age of 45 within the KLoSA, who were surveyed from 2008 to 2018. A total of 2707 men and 5196 women over the age of 60 were included in the current analyses. The study was approved by the Institutional Review Board of Yonsei University Hospital (No. 4-2021-0120).
Dependent variable: cognitive function
Cognitive function was calculated via the Korean version of Mini Mental State Examination (K-MMSE). The K-MMSE assesses orientation, recall, language, registration, attention, calculation, and the ability to follow simple commands, with a sensitivity of 0.70–0.
83 in detecting dementia16. The total score ranges from 0 to 30, with higher scores indicating better cognitive function.
K-MMSE has been validated in Korean sample with high concurrent validity with another brief measure of cognitive functioning (Bless Orientation Memory Information r = 0.78)16.
Independent variable: a change in social engagement
In the KLoSA, respondents’ engagement in social activities was assessed by the following question: “Are you participating in the following organization(s)?” Social engagement was categorized by participation in any of the following activities: religious, senior center, leisure, culture, or sport, family or school reunion, volunteer, and political. Using an approach similar to that of a previous study17, we employed a linear interpolation data step using the LAG function in SAS, to return adjacent values for social engagement stored previously within our study period. Changes in social engagement were defined as a sudden change in survey response, relative to a consecutive number of unanimous responses in the lag queue. Change in social engagement was classified into the following four categories: (1) consistently engaged, (2) non-engaged to engaged, (3) engaged to non-engaged, and (4) consistently non-engaged. For example, “consistently engaged” indicates the consistent social engagement in 2008 and 2010, in 2010 and 2012, in 2012 and 2014, in 2014 and 2016, and in 2016 and 2019; and “non-engaged to engaged” indicates non-engagement in social activities in 2008 (2010, 2012, 2014, or 2016) than engagement in 2010 (2012, 2014, 2016, or 2018)17.
We included multiple covariates including age, socio-economic status (SES), psychosocial and behavioral factors, and health status in the analyses. SES included income and home ownership.
Psychosocial factors included marital status, household size, and having depressive symptoms.
We generated a dichotomous variable to assess whether respondents had significant depressive symptoms the 10-item short-form Center for Epidemiological Studies-Depression (CES-D-10) with a cutoff score of 10.
Behavioral factors included drinking and smoking status, and health-related factors included self-reported health status (from very bad to very good) and number of chronic illnesses (history of clinical diagnosis of hypertension, diabetes, cancer, chronic lung disease, chronic hepatitis, cerebrovascular diseases, mental diseases, and/or arthritis).
Descriptive statistics were used to summarize sample characteristics at baseline as frequencies (%, N). To prevent longitudinal and sampling biases resulting from systemic sampling, weights were provided by KLoSA for each wave, to produce unbiased parameter estimates.
For the multiple imputation of missing values, hot decks (original, bounded, generalized estimating equation (GEE), regression) were selected a modified predictive mean matching technique using SAS Macro. Effect sizes were estimated using Cohen’s d techniques.
Analysis of variance (ANOVA) was used to analyze the distribution of K-MMSE scores over the entire time period in association with social engagement. Sociodemographic characteristics of study participants and average K-MMSE scores were calculated for the study period.
Our data consisted of multiple imputed values calculated by the makers of the KLoSA research group, to minimize bias, which consisted of 8.5% of missing data on income characteristics. The hot-deck method with modified predictive mean matching was used because of the high proportion of missing data regarding this characteristic.
A weighted, GEE model was used to analyze the association between change in social engagement and cognitive function for men and women. All analyses were conducted using SAS version 9.4 (Cary, NC).
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the Declaration of Helsinki (1964) and its later amendments or comparable ethical standards. The study was approved by the Institutional Ethics Board of Yonsei University Hospital (No. 4-2021-0120).
The detailed breakdown of participants’ baseline characteristics and average K-MMSE scores for each independent variable at baseline by gender are summarized in Table 1. A sample of 2707 Korean men (mean age = 67.86, standard deviation (SD) = 490.
41) and 5196 Korean women (mean age = 72.49, standard deviation (SD) = 463.54), from 2008 to 2018, were measured. Among middle-aged and older adults with consistent engagement in social activities, mean K-MMSE scores were 25.05 and 21.
33 for men and women respectively, which corresponded to a medium effect size in favor of men (Cohen’s d = 0.64, 95% CI 0.46–0.81). Contrastingly, mean K-MMSE scores were 23.30 and 20.
78 for men and women respectively among those with consistent non-engagement, which corresponded to a small effect size in favor of men (Cohen’s d = 0.34, 95% CI 0.29–0.40).
Table 1 Sociodemographic characteristics of study participants and average K-MMSE scores (2008–2018).
Table 2 presents the results of the GEE model which assessed the association between change in social engagement and cognitive function.
As shown in the final adjusted GEE models, both men and women who consistently did not engage in social activities (religious, senior center, sport, reunion, voluntary, political) had significantly lower cognitive function than those who consistently engaged in social activities (β = − 1.987, p = 0.000 in men; β = − 1.743, p