Simple lifestyle modifications can protect the brain from the effects of aging - 4 tips on how to reverse the cognitive decline

Highlights:

• Cognitive decline is a part of the aging process that can be slowed down or even halted with simple lifestyle modifications
• Dietary measures, like maintaining proper levels of vitamins and implementing whole diets like the Mediterranean diet, can preserve the brain function
• Physical activity such as aerobic and resistance exercise act as a protective factor for the brain
• Social participation and continuous learning help preserve brain function and memory

Introduction

The effects of the aging process on the brain are multifactorial, causing changes affecting the brain size, vessels, and cognition. Due to changes at the molecular level, the brain shrinks at the morphological level. The reduction in size starts around the age of 40, with about a 5% decline per decade, particularly in the frontal cortex (which performs functions related to cognition). In addition, the aging process causes a reduction in the levels of neurotransmitters and hormones. These changes increase the risk of stroke, white matter lesions, dementia, and memory impairment. Diet, physical activity, and cognitive training are suggested techniques to fight the brain-aging process.

Diet as a protective factor against brain aging

Lifestyle modification in the form of dietary intervention to slow down the decline in cognitive capacity has been thoroughly explored. Several studies have yielded positive results for some dietary components, like B vitamins, fatty acids, and antioxidants (1). Other studies have looked at the whole diet and found that the Mediterranean diet (MeD) and the dietary approaches to stop hypertension diet (DASH) demonstrated an improved cognitive functioning in relation to age (1).

Evidence from observational and interventional studies has highlighted vitamins' importance for neural health, hence cognitive wellness. The literature has mentioned that the B vitamins group comprising comprising B3 (niacin), B6 (pyridoxine), B9 (folic acid), and B12 (cobalamin) are important for proper cognitive function through their influence on homocysteine (an amino acid that plays a role in cardiovascular and cognitive health) and by acting as antioxidants (1-4). Further evidence has suggested that individuals with low levels of vitamins C and B12 performed poorly in cognitive and memory tests (1). This data was solidified by results from other studies, where individuals with low levels of vitamins B9 and B12 were twice as likely to develop dementia than older adults who were supplemented with these vitamins (5, 6). This information was confirmed by results from a recent meta-analysis by Li et al., who found that B vitamins supplementation might delay or even halt the cognitive decline in older adults (7). The researchers also recommended supplementing B vitamins to prevent cognitive impairment. Similarly, evidence supporting the use of vitamin C has also been assessed in systematic reviews, where results revealed that individuals with higher concentrations of the vitamin were more cognitively intact (8). The value of vitamin D in fighting the age-related decline in the brain has also been shown. In this context, a decrease in vitamin D levels has been associated with an accelerated reduction in cognitive capacity (9). This is important because the deficiency does not only cause cognitive decline due to increased activity of aging processes but also due to early initiation of the onset of age-related conditions like Alzheimer's disease. The results highlighting the importance of vitamin D in preserving cognitive function have also been validated in a meta-analysis study by Goodwill and Szoeke, who found that low vitamin D corresponded to lower cognition (10). However, the authors mentioned that further studies are required to define the cut-off age that would provide the best outcomes in terms of vitamin D supplementation. Other vitamins that are of value in fighting age-related cognitive decline by acting as antioxidants include vitamins A and E (1). In addition to the previous, dietary components like choline and magnesium have also been found to present a value when combined with said vitamins (11, 12). Creatinine is another supplement that has been shown to improve cognitive function and memory (13).

Fatty acids, namely omega-3 and omega-6, have been suggested to be an important dietary component that fights the age-related decline in brain function (1). Omega-3 fatty acids are derived from marine sources, like fish, while omega-6 is found in legumes, nuts, and other plant-based foods. Studies have mentioned that omega-3 fatty acids counteract the cognitive decline by acting as a protective factor for the neurons and their membrane intactness by supporting their structural and functional integrity (1, 14). The literature has also mentioned that a high omega-6:3 ratio (optimal is frequently viewed as 1:1, but it is not an absolute value) was linked with cognitive decline in adults (15). Overall, evidence from multiple systematic reviews and meta-analyses suggests the benefits of consuming omega-3 in preserving cognitive function from age-related degeneration, albeit some of them highlight limited benefits, thus requiring further investigation (16, 17).

In addition to nutritional components, the research has also assessed the role of diets in promoting cognitive health and slowdown of age-related decline. MeD diet consists of a variety of fruits, vegetables, cereals, legumes, and other options (1). In addition, it is characterized by a low intake of dairy products, meat, and saturated fatty acids. Multiple studies across different populations have indicated that the MeD diet slows down the rate of cognitive decline and dementia (18, 19). In addition to data from observational and interventional studies, the benefits obtained from MeD have been highlighted in multiple systematic reviews and meta-analyses that found out that adherence to MeD resulted in reduced incidence of cognitive disorders and improved mental performance (17, 20, 21). Similarly, the DASH diet, which emphasizes a greater intake of fruits, vegetables, and whole grains, produced similar results to MeD in improving cognitive functioning and reducing age-related decline (1, 17, 22). Other diets and approaches with similar results include the Okinawan diet and caloric restriction.

Exercise and physical activity support healthy brain aging

Evidence from preclinical and clinical studies mentions that physical activity positively affects learning and memory (23). In addition, it remains one of the effective methods that can be utilized to delay and/or blunt age-related decline in cognitive function and brain atrophy. Evidence from multiple studies highlights that individuals who maintain an active lifestyle are less likely to suffer from cognitive impairment and dementia (23-25). The results from a meta-analysis by Blondell et al. demonstrated that moderate and high physical activity levels act as protective factors against cognitive decline (26). Both aerobic exercises and resistance training have been suggested to slow down age-related cognitive decline.

According to the literature, aerobic exercises have been found to improve cognitive performance and reduce the decline in function, especially in healthy older adults (27). Aerobic exercises include various activities like walking, bicycle riding, dance-based aerobic exercises, handball, Tai Chi, and many other sports (28). The value of these activities has been assessed across many randomized controlled trials, and results revealed that aerobic exercises improve multiple aspects related to cognition and mental capacity (28, 29). A recent meta-analysis performed by Zheng et al. found that aerobic activities enhanced cognitive ability assessed using multiple scores and improved memory in people with mild cognitive impairment (28).

Resistance training is another form of physical activity that has been shown to have positive effects on maintaining cognitive capacity and reducing impairment (30). Examples of strength exercises include weight lifting, resistance bands, and other activities (31). Evidence from the literature highlights that moderate-or high-intensity resistance training resulted in improved short- and long-term memory assessed via several tests (32). The value of resistance training has been validated in a recent meta-analysis which concluded that the overall cognitive function improved in older adults who performed the said kind of physical activity (33).

Overall, an overwhelming body of evidence recommends combining both resistance training and aerobic exercise to maximize the potential of physical activity in combating the age-related decline in cognitive capacity (34).  

Utilizing learning and social interaction to protect the brain's health

During adulthood, a person can engage in enriching cognitive experiences, such as reading books, playing instruments, listening to music, pursuing higher studies, and other activities. According to the literature, all the aforementioned activities make individuals more resistant to age-related decline in memory and cognitive function (35). Results from studies highlight that engaging in these activities, even at an old age, can benefit individuals (35, 36). These beneficial effects have been suggested to occur due to increased formation of cognitive reserve driven by diverse input of nerve stimuli.

Similarly, social participation has been viewed as an effective measure to preserve cognitive function. According to studies, social participation increases cognitive capacities through mental stimulation and enhanced brain function (37). Social engagement has also been suggested to improve physical activity by participating in group events that stimulate movement, enhancing cerebral blood flow. The research highlights the benefits of social interactions in middle- and old-aged individuals, leading to improved cognitive function (37, 38).

Tips

Cognitive decline is a consequence of the aging process, yet it can be slowed down or even blunted in some instances. Here are some tips to give to your clients:

• Highlight the importance of having a diverse diet that provides all nutritional needs from vitamins, minerals, and other components, while avoiding the consumption of processed foods.
• Mention that physical activity, both aerobic and resistance training, help in preserving cognitive function and that combining both approaches gives the best results.
• Clarify how social interaction and participation in lifelong learning activities can benefit the overall brain health and improve memory.
• Explain that no single solution can fully protect the brain against aging, yet implementing all these strategies should confer some protection and slow down the impact.

Conclusions

The decline in cognitive function is a normal part of the aging process. There are certain lifestyle modifications that, if implemented correctly, could slow down or even halt the cognitive decline in healthy older adults and those with mild impairment. These lifestyle modifications include diet, physical activity, social interaction, and continuous learning and engagement in mental activities. The said intervention should be supported by maintaining low-stress levels and favorable environmental factors like air quality (39, 40). Taken together, all these factors work by preventing brain shrinking and preserving cognitive functions, therefore fighting the brain-aging process.

Disclaimer: Supplement intake should always be consulted with a physician or pharmacist.

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