Cognitive Health: What’s Good for the Body Is Good for the Brain
By Densie Webb, PhD, RD
Vol. 24 No. 8 P. 10
At some point, almost all clients or patients will become concerned about the possibility of experiencing cognitive decline as they age. Cognitive decline, as defined by the American Psychological Association, is a “reduction in one or more cognitive abilities, such as memory, awareness, judgment, and mental acuity, across the adult lifespan.”1 None of us has control over genetics, which are an important determinant of cognitive functioning. In fact, cognitive functions are highly heritable and polygenic—determined by many different genes. However, environmental factors can interact with these genes to establish differences among individuals in the decline of cognition that can occur with age.2,3
While there are other factors in addition to genetics, over which individuals have little or no control, such as disease and environmental hazards, there are five areas that, if addressed, can reduce the risk of cognitive decline with age. All of the factors, both those that can be controlled and those that cannot, interact with one another, making it impossible to predict how they will impact an individual’s risk. But research shows that, generally speaking, addressing the following five factors, which also are the focus of the recommendations of AARP’s Global Council on Brain Health (GCBH), can 0reduce the risk of cognitive decline.4
1 Plant-Based Diet
The AARP’s GCBH has stated clearly that “Diet impacts brain health.” The 2017 AARP Brain Health and Nutrition survey found that people who often eat well-balanced and nutritious meals report better brain health.4 The adage often repeated is, “What’s good for the heart is good for the brain.” Whitney Linsenmeyer, PhD, RD, LD, a spokesperson for the Academy of Nutrition and Dietetics and a professor of nutrition at St. Louis University, agrees. “The diets that we recommend for heart health and cognitive health have quite a bit in common—mostly vegetables, fruits, whole grains, lean protein, and dairy or dairy alternatives, with limited added sugars, sodium, saturated and trans fats, and moderate or no alcohol. The Mediterranean diet, the DASH diet, and the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet are scientifically sound and well researched.”
The Consensus Statements from the GCBH emphasized that “no single food acts as a silver bullet for improving or maintaining brain health. The combination of different types of food and nutrients together in our diets likely determines health benefits.”
Following any of these healthful dietary patterns also can help with weight management. A recent German study, published in the Journal of Alzheimer’s Disease, which included almost 300,000 subjects, found that being overweight was significantly associated with dementia in women.5
2 Regular Physical Activity
Research shows that physical activity provides a major brain benefit by modulating genes that would otherwise trigger structural and functional changes in the brain, leading to a loss of cognitive functioning.6,7 As such, regular physical activity plays an important role in counteracting normal and pathological aging of the brain. A large body of research has demonstrated that regular aerobic exercise is associated with neuroplastic changes in the brain that can counteract pathological cognitive decline, resulting in better overall cognitive functioning over time.6 A systematic review of 39 randomized controlled trials with a meta-analysis of 36 of the trials found that adults over age 50, regardless of their cognitive status, experience improved cognitive functioning as the result of aerobic exercise and resistance training that lasts at least 45 minutes, just twice per week.8
Studies in the past have reported a strong association between sleep and cognitive function in older adults. Both sleep quantity and sleep quality can affect cognitive functioning and the rate of decline. One recent study that analyzed data from more than 20,000 older participants from England and China found that cognitive function declined significantly faster among individuals with either extremely short sleep duration (up to four hours per night) or extremely long sleep duration (at least 10 hours per night) when compared with individuals who slept an average of seven hours per night.9
A cross-sectional study published in the journal BMC Public Health analyzed the sleep habits of more than 30,000 men and women (average age of 47.5) in China. Self-reported sleep habits were obtained by a questionnaire, and health parameters, such as BMI, blood pressure, blood glucose, and lipid profiles were collected. A trained investigator evaluated cognitive status of the subjects. The researchers concluded that poor sleep quality is associated with low cognitive performance, independent of the presence of a sleep breathing disorder.10
4 Stress Management
Under stressful conditions, cognitive abilities can fall short.11 Stress and anxiety lead to mind wandering, which competes for cognitive resources.12 Acute stress, such as the loss of a job, a short-term illness, a breakup, or a death can affect cognitive function short term. However, chronic stress, such as poverty, an abusive relationship, or a chronic illness, can affect cognitive abilities long term. Over the long term, chronic life stress consistently has been associated with poorer cognitive function, accelerated cognitive decline, and an increased incidence of dementia.13
Any methods applied to reduce stress may lower risk of cognitive decline, whether it’s yoga, meditation, massage, reading, walking, or listening to soothing music.
5 Social Interaction
Interacting with friends and family can have a significant effect on cognitive functioning, according to several studies. One longitudinal study of 217 community-based, cognitively normal older adults found that less social engagement was associated with steeper cognitive decline among those who had higher amyloid-ß levels in the brain.14 Amyloid-ß proteins in the brain are indicative of the damage that occurs with Alzheimer’s disease. Amyloid plaques first develop in the areas of the brain involved with memory and other cognitive functions. Social interaction also was found to improve cognitive performance whether or not amyloid-ß was present in the brain.
The recommendations for brain health to delay or prevent cognitive decline with age are the same for overall good health, whether they include weight management, regulating blood pressure, preventing type 2 diabetes, or reducing the risk of developing CVD. “I appreciate the AARP Global Council on Brain Health’s focus on overall health,” Linsenmeyer says, “and their six pillars of brain health—be social, engage your brain, manage stress, ongoing exercise, restorative sleep, and eat right.”
— Densie Webb, PhD, RD, is a freelance writer, editor, and industry consultant based in Austin, Texas.
1. Cognitive decline. American Psychological Association Dictionary of Psychology website. https://dictionary.apa.org/cognitive-decline. Accessed August 26, 2022.
2. Papenberg G, Bäckman L. The Genetics of Cognitive Abilities. In: Thomas AK, Gutchess A, eds. The Cambridge Handbook of Cognitive Aging. Cambridge University Press; 2020.
3. Neuner SM, Ding S, Kaczorowski CC. Knockdown of heterochromatin protein 1 binding protein 3 recapitulates phenotypic cellular and molecular features of aging. Aging Cell. 2019;18(1):e12886.
4. Global Council on Brain Health. Brain food: GCBH recommendations on nourishing your brain health. https://www.aarp.org/content/dam/aarp/health/brain_health/2018/01/gcbh-recommendations-on-nourishing-your-brain-health.doi.10.26419%252Fpia.00019.001.pdf. Published 2018. Accessed August 25, 2022.
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9. Ma Y, Liang L, Zheng F, Shi L, Zhong B, Xie W. Association between sleep duration and cognitive decline. JAMA Netw Open. 2020;3(9):e2013573.
10. Wang Z, Heizhati M, Wang L, et al. Poor sleep quality is negatively associated with low cognitive performance in general population independent of self-reported sleep disordered breathing. BMC Public Health. 2022;22(1):3.
11. Bogdanov M, Nitschke JP, LoParco S, Bartz JA, Otto AR. Acute psychosocial stress increases cognitive-effort avoidance. Psychol Sci. 2021;32(9):1463-1475.
12. Boals A, Banks JB. Stress and cognitive functioning during a pandemic: thoughts from stress researchers. Psychol Trauma. 2020;12(S1):S255-S257.
13. Scott SB, Graham-Engeland JE, Engeland CG, et al. The Effects of Stress on Cognitive Aging, Physiology and Emotion (ESCAPE) project. BMC Psychiatry. 2015;15:146.14. Biddle KD, d’Oleire Uquillas F, Jacobs HIL, et al. Social engagement and amyloid-ß-related cognitive decline in cognitively normal older adults. Am J Geriatr Psychiatry. 2019;27(11):1247-1256.