insights

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Alzheimer’s disease (AD) is the leading cause of dementia worldwide, with almost 10% of US adults age 65 and over suffering from dementia and 22% with mild cognitive impairment.¹ The number of patients with the disease is expected to triple by 2050.² Data show a disproportionate burden of dementia among older adults who self-identified as Black or African American, of mild cognitive impairment among older adults who identify as Hispanic, and both categories of cognitive impairment among people who had fewer opportunities to obtain education.¹ To date, there are few single treatments, pharmaceutical or otherwise, that can help with this degenerative condition.

However, using a systems biology approach, clinicians can assess patients for mild cognitive decline and early AD and apply a multimodal protocol to individualize treatments for each patient that addresses underlying causes, including but not limited to environmental exposures. In this way, cognitive decline can be arrested and, in some cases, even reversed. In fact, a Lancet report indicates that more than a third of dementia cases could be preventable, many through lifestyle changes.³ What brain health strategies may help patients who are struggling with cognitive decline?

Strategies for Brain Health

For patients concerned about cognitive decline, the additive effect of multiple healthy interventions may be the best approach. The earlier these healthy transitions begin, the better.⁴ These treatments are not only cost effective, they have few to no negative side effects. Lifestyle interventions are only a subset of many potential interventions, including nutrition, stress management, toxin assessment, and much more.

A recently published longitudinal study assessed lifestyle factors to determine their contributions to cognitive function later in life.⁵ The authors conclude that there might be a cumulative effect of small, incremental improvements across a wide range of lifestyle factors, suggesting a “multivariate recipe for cognitive ageing.”⁵ A 2017 meta-review also supports this multi-pronged approach for normal cognitive decline.⁶

Intellectual Challenge

In a recent study, 12 lifestyle interventions were each found to enhance cognitive function, sometimes in as little as a month.⁶ For example, significant results were seen with intellectual challenges like solving crosswords four times a week (47% decrease of dementia risk).⁷ In other studies, either making music⁸ or just listening to Buddhist hymns regularly over four months showed significant cognitive improvement.⁹

When 60 patients with subjective cognitive decline were asked to practice Kirtan Kriya meditation for 12 minutes a day for three months, they showed significant improvement in memory and cognitive performance over that time and beyond, when they were no longer held to their practice.¹⁰ Even less structured activities have positive mental effects. For instance, crafting, playing games, and socializing¹¹ are all linked to reduced risk of cognitive decline.

In the following video, IFM educator Monique Class, MS, APRN, BC, talks about how psychosocial factors influence inflammation and cognitive decline.

Nutrition

The effect of nutrition on cognitive function during aging has attracted quite a bit of interest, and a higher adherence to healthy dietary patterns does seem to be neuroprotective.¹² Some diets, including the Mediterranean diet, may not only be protective against and slow the progression of MCI and Alzheimer’s but also protect against all-cause mortality in patients with these conditions.¹³ However, a number of diets have shown positive effects on cognitive health outcomes, primarily diets with high intake of plants and poly- and monounsaturated fats.^14,15

Nutrition is a key modulator of cognitive health, but what are those specific nutrients and vitamins that support cognition and reduce neurodegeneration? An important consideration is mitochondrial health. Age-related neurodegeneration has been associated with oxidative stress, flawed energy metabolism, and mitochondrial dysfunctions.¹⁶ In animal studies, a variety of vitamins and nutrients have demonstrated protective effects on mitochondria, including coenzyme Q10 (CoQ10),¹⁷ acetyl-L-carnitine (ALC), and resveratrol.¹⁸ And recent clinical studies have also suggested a role for ALC and resveratrol in the potential delay of cognitive decline.^19,20 The coenzyme nicotinamide adenine dinucleotide (NAD) also influences many key cellular functions, including processes that are critical for maintaining metabolic homeostasis and for healthy aging.²¹

For further reading on the connection between cognitive decline and nutrition, please see the following articles:

• Nutrition: A Key Modulator of Cognitive Health
• Can Diet Cut Mild Cognitive Impairment Risk in Half?
• Dementia Prevention – Reducing Risk With Increased Dietary Fiber
• Modest Long-Term Intake of Flavonoids May Reduce Dementia Risk
• Personalizing Nutritional Interventions

EXERCISE

Exercise is one of the strategies that has been shown to optimize both mitochondrial and cognitive function, potentially decelerating cognitive decline and attenuating neurodegeneration. Studies have suggested that physical activity may delay brain aging and degenerative pathologies, improve cognitive processes and memory, and even promote a sense of well-being.²² A 2019 meta-analysis assessed 48 studies that compared the effects of exercise on both physical and cognitive function in older adults (60 years of age or older) and suggested that exercise training has a significant benefit, improving both functions in this population.²³ Other recent meta-analyses and controlled trials have found that several different types of physical activity, including the following, may improve attention, executive function, and memory:

• Both low to moderate and high intensity exercise^24,25
• Short-term interval training and aerobic exercise^26,27
• Social dancing²⁸
• Multimodal physical exercise²⁹
• Mind-body exercises such as tai chi, yoga, and qigong³⁰

One component of exercise benefits on brain health is the optimization of mitochondrial function. Aging has been associated with a decrease in specific mitochondrial functions, such as biogenesis and mitophagy.³¹ In addition, neuroinflammation, oxidative stress, and mitochondrial dysfunction have all been noted in the progression of neurodegenerative disorders such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and multiple sclerosis (MS).^32,33 Research suggests that physical activity may have an anti-aging impact through the improvement of mitochondrial functions and by contributing an anti-inflammatory effect.^31,34

• Exercise may protect neurons against dysfunction and degeneration as the neurons respond to activity by activating signaling pathways, including those that stimulate mitochondrial biogenesis such as transcription factor coactivator PGC-1a and those that upregulate autophagy and mitophagy.^22,29
• Both endurance activity and resistance exercise may induce an increase of circulating neurotrophins such as brain-derived neurotrophic factor (BDNF), which in turn stimulates mitochondrial biogenesis.²²
• Exercise may also impact the regulation of neuroinflammation and glial activation, which both play active roles in neurodegenerative diseases. A 2019 review found that while the mechanisms have not been clearly determined, exercise may regulate microglial activation through an increase in anti-inflammatory factors.³⁴

From improving neuroplasticity and preserving neuronal function to enhancing quality of life, exercise is an important part of a patient’s personalized clinical intervention for boosting cognitive function and slowing neurodegeneration.

Functional Medicine Considerations

Clinical understanding of how nutrition and other lifestyle factors like intellectual challenge and exercise support cognition and optimal brain function continues to evolve. Within the functional medicine framework, practitioners collaborate with patients to develop personalized therapeutic strategies that are most beneficial to their current conditions and concerns. Treatments for patients with cognitive issues and those concerned about brain-aging may include support of mitochondrial health and concurrent consideration of multiple lifestyle factors, including exercise, nutrition, intellectual challenge, sleep, and relationships. Gain additional insights and tools on cognitive decline by becoming an IFM member now. Working together as a medical community, we can continue to optimize the approach to the prevention and reversal of cognitive decline.

Related Articles

Environmental Toxicants: A Risk Factor for Neurodegenerative Diseases

Hearing Aids as Cognitive Health Aids

Clinical Application & Treatment for Neurodegenerative Decline

References

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