How Diet and Lifestyle Modifications Can Improve Cognitive Function in the Elderly

From birth to our final days, time marches forward whether we like it or not, and aging is no different. Because neurons are delicate and finite, many people question what can be done to improve declining cognitive function caused by natural aging. Select foods, vitamins, and cardiovascular activity have all been proven in clinical literature to be essential components of improving the health of our encephala.

Walnuts are full of antioxidants, fatty acids, and protein, with evidence showing they may be beneficial in preserving brain health in relation to cognitive impairment. Walnuts exhibit their neuroprotective effects through decreasing inflammation, oxidative stress, and Aβ-induced DNA/membrane damage.¹

One trial completed in Spain found that healthy, elderly people on a Mediterranean diet with 15 g of walnuts had significant improvements in cognition compared with the control group, which was on a low-fat diet.²

Another trial noted older women consuming 5 servings of walnuts a week or more had cognitive improvements worth 2 years of cognitive aging equivalents compared with women who didn’t consume walnuts.³ As a reference, a 1-ounce serving—or 12-14 halves—would provide adequate supplementation to the diet.⁴ People who can’t enjoy walnuts due to allergies can easily get their antioxidant effects from other sources.

Vitamin E, another antioxidant, can protect neurons from harmful effects of oxidative damage. A meta-analysis from 2013 looked at 53 trials exclusive to vitamin E use.⁵

When vitamin E is used in combination or alone at doses higher than the RDA (15 mg), there is an increased mortality associated.⁵ Essentially, not all vitamins at supratherapeutic doses are safe to use, so it is important to know what RDAs are and how they play into vitamin recommendations.

Cyanocobalamin, formerly known as vitamin B₁₂, is essential to the body for cellular metabolism and generation of methionine, the start codon for DNA synthesis. Elderly patients, as well as those who take proton pump inhibitors or histamine-2 receptor antagonists, are at an increased risk of vitamin B₁₂ deficiency due to absorption complications.⁶

Major deficits in vitamin B₁₂ can cause food-cobalamin malabsorption syndrome, which can impact cognition.⁶ Symptoms can manifest as visual impairments, memory loss, and disorientation; therefore, vitamin B₁₂ supplementation can improve the symptoms of food-cobalamin malabsorption syndrome.⁶

To prevent this vitamin deficiency, it is recommended that patients on acid-suppressant therapy consume the RDA (2.4 mcg/day) through supplements or fortified foods (milk, eggs, fortified cereal, etc).⁶ While nutrition is important, physical activity also plays a significant role in brain health.

Both animal and human studies have shown that chronic exercise results in an elevation of cerebral blood flow at rest, more so than in sedentary individuals. In humans, this has been demonstrated by an increased velocity of blood flow through the middle cerebral artery.⁷

Additional animal studies have shown aerobic exercises, such as running, may result in growth of new capillary beds primarily within the motor cortex of the brain. When neovascularization was inhibited in animals, there was no increase in cerebral blood flow velocity after exercise as compared to the control group.^7,8

This suggests that one mechanism by which exercise increases global brain perfusion is by generating growth of new microvascular networks within the cortex.⁷ Because the aging process is associated with a decline in cerebral blood flow velocity and cognitive function, physical exercise training may be the remedy for both. The cognitive function decline, experienced with aging, may be prolonged in exercise-trained, older adults due to their increased rate of blood flow and cerebrovascular function.⁹

There is evidence available showing that increased exercise levels during adolescence have a lasting neuroprotective impact into adulthood. One study showed that children with higher levels of aerobic fitness performed better at cognitive tasks, and when compared to young adults 18 to 30 years of age, they were statistically more cognitively similar to this age group than were children of lower fitness levels.¹⁰

In fact, lower levels of aerobic fitness corresponded to lower response speed as well as accuracy at the same cognitive tests.¹⁰A multitudinous collection of research has demonstrated, regardless of age, higher levels of physical fitness corresponds to better performance on cognitive exercises. Furthermore, better fitness and activity levels at a younger age may exert lasting protection from the risk of cognitive impairment in the future.¹¹

These findings raise an important question: is one type of exercise superior at improving cognitive function and promoting lasting benefits on future brain health? One study that compared resistance training to balance exercises in women found resistance training produced a greater increase in cerebral perfusion during a number of cognitive tests.¹² Another study found that multicomponent exercise programs incorporating strength, aerobics, and balance training improve memory, cognitive function, and brain atrophy rates.¹³

In essence, our minds require proper diet and exercise to work at an optimal level. Through the practice of mentally stimulating physical activity and quality diet measures, elderly patients can help improve their current brain status and protect themselves from neurodegeneration until the end of life.

References

• Chauhan A, Chauhan V. Beneficial effects of walnuts on cognition and brain health. Nutrients. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7071526/. Published February 20, 2020. Accessed January 27, 2021.
• Martínez-Lapiscina EH, Clavero P, Toledo E, Estruch R, Salas-Salvadó J, San Julián B, Sanchez-Tainta A, Ros E, Valls-Pedret C, Martinez-Gonzalez MÁ. J Neurol Neurosurg Psychiatry. 2013 Dec; 84(12):1318-25. Accessed February 6th, 2021.
• Arab L, Ang A. J Nutr Health Aging. 2015 Mar; 19(3):284-90. Accessed February 6th, 2021
• Nutrition Information. California Walnuts. https://walnuts.org/nutrition/nutrition-information/. Published April 24, 2020. Accessed February 7, 2021.
• Bjelakovic G, Nikolova D, Gluud C. Meta-regression analyses, meta-analyses, and trial sequential analyses of the effects of supplementation with beta-carotene, vitamin A, and vitamin E singly or in different combinations on all-cause mortality: do we have evidence for lack of harm? PLoS one. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3765487/. Published September 6, 2013. Accessed January 26, 2021.
• Stover PJ. Vitamin B12 and older adults. Current opinion in clinical nutrition and metabolic care. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5130103/. Published January 2010. Accessed January 26, 2021.
• Barnes JN. Exercise, cognitive function, and aging. Adv Physiol Educ. 2015;39(2):55-62. doi:10.1152/advan.00101.2014. Accessed January 31, 2021.
• (Gertz K, Priller J, Kronenberg G, Fink KB, Winter B, Schrock H, Ji S, Milosevic M, Harms C, Bohm M, Dirnagl U, Laufs U, Endres M. Physical activity improves long-term stroke outcome via endothelial nitric oxide synthase-dependent augmentation of neovascularization and cerebral blood flow. Circ Res 99: 1132—1140, 2006). Accessed February 2, 2021.
• Davenport MH, Hogan DB, Eskes GA, Longman RS, Poulin MJ. Cerebrovascular reserve: the link between fitness and cognitive function? Exerc Sport Sci Rev 40: 153—158, 2012. Accessed January 30, 2021.
• Voss MW, Chaddock L, Kim JS, et al. Aerobic fitness is associated with greater efficiency of the network underlying cognitive control in preadolescent children. AFNeuroscience. 2011 Dec 29; 199():166-76. Accessed January 30, 2021.
• Nyberg J, Åberg MA, Schiöler L, Nilsson M, Wallin A, Torén K, Kuhn HG Cardiovascular and cognitive fitness at age 18 and risk of early-onset dementia.Brain. 2014 May; 137(Pt 5):1514-23. Accessed February 1, 2021.
• Xu X, Jerskey BA, Cote DM, et al. Cerebrovascular perfusion among older adults is moderated by strength training and gender. Neurosci Lett. 2014;560:26-30. doi:10.1016/j.neulet.2013.12.011. Accessed February 6, 2021.
• Suzuki T, Shimada H, Makizako H, et al. A randomized controlled trial of multicomponent exercise in older adults with mild cognitive impairment. PLoS One. 2013; 8(4):e61483. Accessed February 3, 2021.