J Neurol Res

Journal of Neurology Research, ISSN 1923-2845 print, 1923-2853 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Neurol Res and Elmer Press Inc

Journal website http://www.neurores.org

Review

Volume 10, Number 3, June 2020, pages 56-68

Neurocognitive Performance of African Americans and Hispanic Adults in Relation to Diet and Physical Activity: A Literature Review

**Table 1.** Study Selection Criteria
Inclusion criteria	Description
PCP: primary care physician; HbA1C: hemoglobin A1C.
Types of studies	Publication date: January 1, 2000 and February 28, 2020
	Studies from any geographical location, USA preferred but not required
	English
	1) Studies using qualitative, quantitative, and mixed methods of analysis that seek to understand the patient experience through direct contact with patients or direct observation and that describe the processes of lifestyle program implementation and management; 2) Studies should include data about weight management and related comorbidities, a specific description of diet planning or changes, and a description of the patients’ level of physical activity. These include original studies like lifestyle interventions and observational studies involving an assessment of physical activity, diet, and cognitive function; and 3) Systematic reviews and meta-analyses with the highest quality evidence on a research topic
Types of participants	Adults (> 40 years old) of African American or Hispanic origin
	Overweight or obese (body mass index of 25.0 or higher) and diagnosed with at least one comorbidity
	1) Being treated in any “usual care” setting: primary, secondary, or tertiary care (e.g. hospital, hospice, community, home, or rehabilitation facility); and 2) Tested (e.g. physical measurements, blood work, and neuropsychological assessment if present)
	Other characteristics: 1) Receiving care typical for that geographical location (e.g. diet counseling conducted by PCP); and 2) Participants of experimental or pilot studies (e.g. lifestyle intervention programs and diet studies)
Types of outcome measures	1) Weight changes and their pattern; 2) Diet profile changes and their pattern; 3) Physical activity changes; 4) HbA1c or similar values; glycemic control; 5) Neuropsychological performance linked to changes described above; and 6) Technical burdens (e.g. enacting lifestyle changes, performing exercises, modifying environments, taking medications, and using assistive technologies)

Table 1. Study Selection Criteria

Inclusion criteria

Description

PCP: primary care physician; HbA1C: hemoglobin A1C.

Types of studies

Publication date: January 1, 2000 and February 28, 2020

Studies from any geographical location, USA preferred but not required

English

1) Studies using qualitative, quantitative, and mixed methods of analysis that seek to understand the patient experience through direct contact with patients or direct observation and that describe the processes of lifestyle program implementation and management; 2) Studies should include data about weight management and related comorbidities, a specific description of diet planning or changes, and a description of the patients’ level of physical activity. These include original studies like lifestyle interventions and observational studies involving an assessment of physical activity, diet, and cognitive function; and 3) Systematic reviews and meta-analyses with the highest quality evidence on a research topic

Types of participants

Adults (> 40 years old) of African American or Hispanic origin

Overweight or obese (body mass index of 25.0 or higher) and diagnosed with at least one comorbidity

1) Being treated in any “usual care” setting: primary, secondary, or tertiary care (e.g. hospital, hospice, community, home, or rehabilitation facility); and 2) Tested (e.g. physical measurements, blood work, and neuropsychological assessment if present)

Other characteristics: 1) Receiving care typical for that geographical location (e.g. diet counseling conducted by PCP); and 2) Participants of experimental or pilot studies (e.g. lifestyle intervention programs and diet studies)

Types of outcome measures

1) Weight changes and their pattern; 2) Diet profile changes and their pattern; 3) Physical activity changes; 4) HbA1c or similar values; glycemic control; 5) Neuropsychological performance linked to changes described above; and 6) Technical burdens (e.g. enacting lifestyle changes, performing exercises, modifying environments, taking medications, and using assistive technologies)

**Table 2.** Components of Physical Activity That Provide Cognitive Function Benefits
Component	Description	Examples	References
Regular sustained aerobic exercise	Aerobic exercises are associated with significant improvements in the majority of cognitive domains	Brisk walking, dancing, jogging, cycling, and swimming	Antunes et al, 2015 [37]; Erickson et al, 2011 [38]; Colcombe et al, 2006 [39]
Regular strength, weight, or resistance training	Resistance training appears to have positive effects on cognition	Squeezing rubber balls, using elastic resistance bands, and lifting weights	Landrigan et al, 2019 [40]; Suijo et al, 2013 [41]
Flexibility and balance training	These exercises may help patients perform movements necessary for safe mobility; their effect on cognition is unclear	Bending and stretching, tai chi, yoga, and pilates	Teri et al, 2008 [42]

Table 2. Components of Physical Activity That Provide Cognitive Function Benefits

Component

Description

Examples

References

Regular sustained aerobic exercise

Aerobic exercises are associated with significant improvements in the majority of cognitive domains

Brisk walking, dancing, jogging, cycling, and swimming

Antunes et al, 2015 [37]; Erickson et al, 2011 [38]; Colcombe et al, 2006 [39]

Regular strength, weight, or resistance training

Resistance training appears to have positive effects on cognition

Squeezing rubber balls, using elastic resistance bands, and lifting weights

Landrigan et al, 2019 [40]; Suijo et al, 2013 [41]

Flexibility and balance training

These exercises may help patients perform movements necessary for safe mobility; their effect on cognition is unclear

Bending and stretching, tai chi, yoga, and pilates

Teri et al, 2008 [42]

**Table 3.** Summary of Dietary Factors and Their Effect on Cognitive Function
Dietary factor	Description	References
Lower intake of saturated and trans unsaturated fats	Intake levels of both saturated and transfat are positively and significantly associated with Alzheimer’s disease risk	Morris et al, 2003 [61]; Laitinen et al, 2006 [62]
Higher intake of monounsaturated and polyunsaturated fats	Increased intake of monounsaturated and polyunsaturated fats may decrease the risk of cardiovascular accidents but has limited impact on cognitive decline	Ruan et al, 2018 [63]; Briggs et al, 2017 [64]
Higher consumption of omega-3 fatty acids	Regular intake of omega-3 fatty acids may provide some benefits for patients with dementia, but these effects are limited	Burckhardt et al, 2016 [65]; Lim et al, 2006 [66]
Intake of some antioxidants and vitamins	Vitamin and/or antioxidant consumption has no clear effect on cognitive decline	Luchsinger et al, 2003 [67]; Polidori et al, 2014 [68]
Limited alcohol consumption	The risk of cognitive decline is higher in people who abstained from alcohol or consumed > 14 units/week	Koch et al, 2019 [69]; Severine et al, 2018 [70]
Higher percentage of fruits and vegetables in diet	A diet with a higher consumption of fruits and vegetables is associated with a reduced risk of cognitive impairment	Jiang et al, 2017 [71]

Table 3. Summary of Dietary Factors and Their Effect on Cognitive Function

Dietary factor

Description

References

Lower intake of saturated and trans unsaturated fats

Intake levels of both saturated and transfat are positively and significantly associated with Alzheimer’s disease risk

Morris et al, 2003 [61]; Laitinen et al, 2006 [62]

Higher intake of monounsaturated and polyunsaturated fats

Increased intake of monounsaturated and polyunsaturated fats may decrease the risk of cardiovascular accidents but has limited impact on cognitive decline

Ruan et al, 2018 [63]; Briggs et al, 2017 [64]

Higher consumption of omega-3 fatty acids

Regular intake of omega-3 fatty acids may provide some benefits for patients with dementia, but these effects are limited

Burckhardt et al, 2016 [65]; Lim et al, 2006 [66]

Intake of some antioxidants and vitamins

Vitamin and/or antioxidant consumption has no clear effect on cognitive decline

Luchsinger et al, 2003 [67]; Polidori et al, 2014 [68]

Limited alcohol consumption

The risk of cognitive decline is higher in people who abstained from alcohol or consumed > 14 units/week

Koch et al, 2019 [69]; Severine et al, 2018 [70]

Higher percentage of fruits and vegetables in diet

A diet with a higher consumption of fruits and vegetables is associated with a reduced risk of cognitive impairment

Jiang et al, 2017 [71]