Journal of Human Nutrition and Dietetics
PUBLIC HEALTH NUTRITION AND EPIDEMIOLOGY Nutrient intake among US adults with disabilities R. An, C.Y. Chiu, Z. Zhang & N. A. Burd Department of Kinesiology and Community Health, College of Applied Health Sciences, University of Illinois at Urbana-Champaign, Champaign, IL, USA
Keywords nutrient intake, diet, dietary supplement, disability, functional limitation. Correspondence R. An, Department of Kinesiology and Community Health, College of Applied Health Sciences, University of Illinois at UrbanaChampaign, 1206 S 4th Street, Champaign, 61820 IL, USA. Tel.: +1 217 244 0966 Fax: +1 217 333 2766 E-mail: [email protected] How to cite this article An R., Chiu C.Y., Zhang Z., Burd N.A. (2015) Nutrient intake among US adults with disabilities. J Hum Nutr Diet. 28, 465–475 doi:10.1111/jhn.12274
Abstract Background: Physical, mental and financial barriers among persons with disabilities limit their access to healthier diet. The present study investigated the relationship between disabilities and nutrient intake among US adults. Methods: Data originated from National Health and Nutrition Examination Survey 2007–2008 and 2009–2010 waves (n = 11 811). Five disability categories include activities of daily living (ADLs), instrumental activities of daily living (IADLs), leisure and social activities (LSAs), lower extremity mobility (LEM) and general physical activities (GPAs). Nutrient intakes from food and dietary supplements were calculated from 24-h dietary recalls. Adherence to dietary reference intakes and dietary guideline recommendations was compared between people with and without disabilities and across disability categories in the statistical analysis. Results: GPAs, IADLs, LSAs, LEM and ADLs occupied 24.5%, 13.3%, 9.9%, 9.2% and 9.2% of US adults, respectively (not mutually exclusive). Only 42.3%, 11.3%, 63.8%, 47.7%, 48.7%, 9.7%, 48.7%, 90.7%, 21.7% and 4.7% of adults had saturated fat, fibre, cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium and potassium intakes from food within recommended levels, respectively. Dietary supplement use moderately improved vitamin C, vitamin D and calcium intakes. People with disabilities were less likely to meet recommended levels on saturated fat, fibre (except GPAs), vitamin A (except GPAs), vitamin C (except GPAs), calcium and potassium intakes than persons without disability. Nutrient intake differed across disability categories, with ADLs least likely to meet recommended intakes. Conclusions: Interventions targeting persons with disabilities through nutrition education and financial assistance are warranted to promote healthy diet and reduce disparities.
Introduction Improving diet quality is a key health promotion strategy. From 1980 onward, a major theme of the US federal dietary guidelines has been to increase the consumption of nutrient-rich foods and reduce the consumption of energy-dense foods (US Department of Agriculture & US Department of Health & Human Services, 2010). However, a large majority of the US population fail to meet those guidelines, with insufficient consumption of nutrient-rich foods and excessive discretionary energy intake (Krebs-Smith et al., 2010). In 2005, over one-fifth of all ª 2014 The British Dietetic Association Ltd.
US adults self-reported having a disability (Centers for Disease Control & Prevention, [CDC], 2009a). Compared to those without any disability, various physical, mental and financial barriers among persons with disabilities limit their access to healthier diet (Lee & Frongillo, 2001a,b; Webber et al., 2007; Wylie et al., 1999). Specific barriers include difficulties in chewing or swallowing (Cabre et al., 2010), loss of appetite caused by pain or side effects of medication (Ross & Crook, 1998), intellectual disability or mobility impairments that restrain grocery shopping and food preparation (Tsai et al., 2011), as well as financial strain as a result of unemployment 465
Nutrient intake and disability
(Turner, 1995). Given these common barriers among persons with disabilities, poor diet quality and insufficient nutrient intake may have an even more detrimental impact on their health in the process of ageing. In the US and worldwide, the rise in noncommunicable diseases and years lived with potentially disabling illnesses and injuries calls for adequate nutrition for persons with disabilities, whereas the relationship between disability and dietary intake has largely been overlooked and the relevant literature remains scarce (Groce et al., 2013). Existing studies often focus on a particular gender, age or residential group using nonrepresentative samples, which confines the generalisability of findings (Sharkey et al., 2003; Houston et al., 2005; Tomey et al., 2008). There are only two studies that have provided national estimates for dietary intake among the US population with disabilities. Using the National Health and Nutrition Examination Survey (NHANES) 1999–2004 waves, increased selfreported disability in lower extremity mobility and general physical activities was found to be linked to lower Healthy Eating Index scores (Xu et al., 2012). However, the outcome measure and study subjects were restricted to an overall diet index (instead of individual nutrients) and to people aged ≥60 years. An & Chiu (2014) examined the relationship between disability status and vegetable/fruit intake among US adults using the Behavioral Risk Factor Surveillance System 2011 wave. Persons with disabilities were shown to consume vegetable/fruit less frequently than disability-free individuals. The present study examined the relationship between disabilities and nutrient intake among US adults aged ≥20 years using a nationally representative sample from the NHANES 2007–2008 and 2009–2010 waves. Disability is classified into five categories using validated indices. Daily intakes of saturated fat, fibre, cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium and potassium from food and dietary supplements were calculated from two consecutive 24-h dietary recalls. Adherence to recommended daily nutrient intake levels between persons with and without disability and across disability categories was examined in bivariate and multivariate analyses, accounting for the NHANES multiyear complex sampling design. Materials and methods Participants Individual-level data originated from NHANES 2007– 2008 and 2009–2010 waves. NHANES is a programme of studies designed to assess the health and nutritional status of adults and children and represents a multistage probability sample of the US civilian, noninstitutionalised population. The NHANES programme began in the early 1960s and periodically conducted separate surveys focus466
R. An et al.
ing on different population groups or health topics. From 1999 onward, NHANES has been conducted continuously in 2-year cycles and has a changing focus on a variety of health and nutrition measurements. Except for the NHANES 1999–2000 wave where all respondents were asked to complete a single 24-h dietary recall interview, all subsequent waves incorporate two dietary recalls, with the first collected in-person and the second by telephone, 3–10 days later. In both interviews, each food item and corresponding quantity consumed by a respondent from midnight to midnight on the day before the interview was recorded. The in-person dietary recall was conducted by trained dietary interviewers in the Mobile Examination Center (MEC) with a standard set of measuring guides. These tools aimed to help the respondent accurately report the volume and dimensions of the food items consumed. Upon completion of the in-person interview, participants were provided measuring cups, spoons, a ruler and a food model booklet, which contained two-dimensional drawings of the various measuring guides available in the MEC for use when reporting dietary intake during the telephone interview. Detailed information on the NHANES protocols are provided on its web portal (http://www.cdc.gov/nchs/nhanes.htm). From 1999–2006, the dietary interviews only asked about food and beverages consumed, and estimating total nutrient intakes from all sources (foods, beverages, and dietary supplements) had been difficult as a result of the different data collection methods, referent time frames and data formats. Beginning in 2007, data were collected on the usage of all vitamins, minerals, herbals and other dietary supplements as part of the dietary interviews (so that, for both dietary recall days, information on food as well as diet supplement is obtained for survey participants). Data on dietary supplement use include supplement type, brand name and quantity consumed. With these data collected using similar methods over the same time frame, nutrients from all sources can be readily combined, which allows researchers to improve total nutrient intake estimations and increases their abilities to estimate percentages of the population with intakes above or below nutrient standards (Centers for Disease Control & Prevention, 2010). The body weight and stature height of NHANES respondents were measured using a digital scale and stadiometer in the MEC. Specific anthropometry procedures apply to wheelchair users, amputees and people with comprehension or language difficulties (Centers for Disease Control & Prevention, 2009b). Body mass index (BMI) is defined as kg m–2. Sociodemographic factors including sex, age, race/ethnicity, marital status, education, and household income were collected through in-person interview. Among the 12 153 adults aged ª 2014 The British Dietetic Association Ltd.
R. An et al.
≥20 years who participated in NHANES 2007–2008 and 2009–2010 waves, 342 were pregnant or were following a special diet, with the aim of losing weight, at the time of interview and were excluded from the the analysis. This resulted in a total effective sample of 11 811. The present study is entirely based upon the de-identified public-use datasets from the NHANES, and thus is exempted from ethnical approval. Disability status In NHANES 2007–2008 and 2009–2010 waves, 19 validated questions were administered to assess five domains of disability: activities of daily living (ADLs), instrumental activities of daily living (IADLs), leisure and social activities (LSAs), lower extremity mobility (LEM) and general physical activities (GPAs). Each question item evaluated the difficulty an individual had in performing a task without the aid of any equipment, and participants were required to choose from among four difficulty levels: ‘no difficulty’, ‘some difficulty’, ‘much difficulty’ and ‘unable to do’. ADLs consist of four activities: dressing oneself; walking between rooms on the same floor; getting in and out of bed; and using a fork, knife and drinking from a cup. IADLs consist of three activities: managing money; doing household chores; and preparing meals. LSAs consist of three activities: going out to movies and events; attending social events; and performing leisure activities at home. LEM consists of two activities: walking a quarter mile and walking up 10 steps. GPAs consist of seven activities: stooping, crouching and kneeling; lifting and carrying; standing up from an armless chair; standing for long periods; sitting for long periods; reaching up over one’s head; and grasping/ holding small objects. Disability is defined as any difficulty in performing at least one of the activities within a given domain. A participant may qualify for more than one disability category, and individuals with no disability refer to those with no difficulty in performing any activities within any of the five disability domains. Five dichotomous variables for ADLs, LSAs, IADLs, LEM and GPAs conditions were constructed, with no disability as their common reference group. Among the total effective sample of 11811, there are 1646, 2266, 1728, 1451 and 3854 participants who reported having ADLs, IADLs, LSAs, LEM and GPAs (not mutually exclusive because it is possible to qualify for multiple disability categories), respectively, whereas 7595 participants had no self-reported disability. Nutrient intake The present study focused on the daily intake of 10 nutrients (saturated fat, dietary fibre, dietary cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium ª 2014 The British Dietetic Association Ltd.
Nutrient intake and disability
and potassium) that are of major public health concern. The Dietary Guidelines for Americans, 2010 (US Department of Agriculture & US Department of Health & Human Services, 2010) cautioned against the low intake of dietary fibre, vitamin D, calcium, iron (especially for women capable of becoming pregnant) and potassium for both adults and children. The Guidelines also identified an excessive intake of saturated fat, dietary cholesterol and sodium in the general population and recommended substantial reduction. The concern regarding insufficient intake of vitamin A and vitamin C appears to have lessened over time but remains. Daily total intake of saturated fat, fibre, cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium and potassium were determined by averaging data from the in-person and telephone interviews, and were separated by daily nutrient intakes from foods only and intakes from both foods and dietary supplements. Daily total energy intake was calculated based on the consumed quantities (g) of carbohydrate, fat, protein and alcohol. Table 1 summarises the recommended daily nutrient intake levels specified in the reference daily intakes (RDIs) (Institute of Medicine, 2011) and the Dietary Guidelines for Americans (US Department of Agriculture & US Department of Health & Human Services, 2010). The RDIs are reference values that are quantitative estimates of nutrient intakes to be used for planning and assessing diets for healthy people. In the RDIs, the estimated average requirement (EAR) is the average daily nutrient intake level estimated to meet the requirement of half the healthy individuals in a particular life stage and gender group, and the tolerable upper intake level (UL) is the highest quantity of daily nutrient intake that is unlikely to pose any health risk to almost the entire population. Adherence to the recommended daily nutrient intake level is defined as daily intake of a nutrient at or above its specific EAR (or dietaryguidelines-recommended level) but below the UL. Individual characteristics Several individual characteristics were controlled for in the multivariate analysis: a dichotomous variable for female (male in the reference group), a continuous variable for age in years, an interaction term between age and female (a product of these two variables), three dichotomous variables for race/ethnicity (Non-Hispanic African American, Non-Hispanic other race or multi-race, and Hispanic, with Non-Hispanic White in the reference group), a continuous variable for BMI, a dichotomous variable for college education (high school education or lower in the reference group), two dichotomous variables for marital status (divorced or separated or widowed, and never married, with married in the reference group), 467
R. An et al.
Nutrient intake and disability Table 1 Recommended daily nutrient intake levels
Nutrient (units) Calories from saturated fat (%) Fibre (g) Cholesterol (mg) Vitamin A (mcg) Vitamin C (mg) Vitamin D (mcg) Calcium (mg) Iron (mg) Sodium (mg) Potassium (mg)
Source of goal
Female 19–30 years
Male 19–30 years
Female 31–50 years
Male 31–50 years
Female 51–70 years
Male 51–70 years
Female ≥71 years
Male ≥71 years
DG
PUBLIC HEALTH NUTRITION AND EPIDEMIOLOGY Nutrient intake among US adults with disabilities R. An, C.Y. Chiu, Z. Zhang & N. A. Burd Department of Kinesiology and Community Health, College of Applied Health Sciences, University of Illinois at Urbana-Champaign, Champaign, IL, USA
Keywords nutrient intake, diet, dietary supplement, disability, functional limitation. Correspondence R. An, Department of Kinesiology and Community Health, College of Applied Health Sciences, University of Illinois at UrbanaChampaign, 1206 S 4th Street, Champaign, 61820 IL, USA. Tel.: +1 217 244 0966 Fax: +1 217 333 2766 E-mail: [email protected] How to cite this article An R., Chiu C.Y., Zhang Z., Burd N.A. (2015) Nutrient intake among US adults with disabilities. J Hum Nutr Diet. 28, 465–475 doi:10.1111/jhn.12274
Abstract Background: Physical, mental and financial barriers among persons with disabilities limit their access to healthier diet. The present study investigated the relationship between disabilities and nutrient intake among US adults. Methods: Data originated from National Health and Nutrition Examination Survey 2007–2008 and 2009–2010 waves (n = 11 811). Five disability categories include activities of daily living (ADLs), instrumental activities of daily living (IADLs), leisure and social activities (LSAs), lower extremity mobility (LEM) and general physical activities (GPAs). Nutrient intakes from food and dietary supplements were calculated from 24-h dietary recalls. Adherence to dietary reference intakes and dietary guideline recommendations was compared between people with and without disabilities and across disability categories in the statistical analysis. Results: GPAs, IADLs, LSAs, LEM and ADLs occupied 24.5%, 13.3%, 9.9%, 9.2% and 9.2% of US adults, respectively (not mutually exclusive). Only 42.3%, 11.3%, 63.8%, 47.7%, 48.7%, 9.7%, 48.7%, 90.7%, 21.7% and 4.7% of adults had saturated fat, fibre, cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium and potassium intakes from food within recommended levels, respectively. Dietary supplement use moderately improved vitamin C, vitamin D and calcium intakes. People with disabilities were less likely to meet recommended levels on saturated fat, fibre (except GPAs), vitamin A (except GPAs), vitamin C (except GPAs), calcium and potassium intakes than persons without disability. Nutrient intake differed across disability categories, with ADLs least likely to meet recommended intakes. Conclusions: Interventions targeting persons with disabilities through nutrition education and financial assistance are warranted to promote healthy diet and reduce disparities.
Introduction Improving diet quality is a key health promotion strategy. From 1980 onward, a major theme of the US federal dietary guidelines has been to increase the consumption of nutrient-rich foods and reduce the consumption of energy-dense foods (US Department of Agriculture & US Department of Health & Human Services, 2010). However, a large majority of the US population fail to meet those guidelines, with insufficient consumption of nutrient-rich foods and excessive discretionary energy intake (Krebs-Smith et al., 2010). In 2005, over one-fifth of all ª 2014 The British Dietetic Association Ltd.
US adults self-reported having a disability (Centers for Disease Control & Prevention, [CDC], 2009a). Compared to those without any disability, various physical, mental and financial barriers among persons with disabilities limit their access to healthier diet (Lee & Frongillo, 2001a,b; Webber et al., 2007; Wylie et al., 1999). Specific barriers include difficulties in chewing or swallowing (Cabre et al., 2010), loss of appetite caused by pain or side effects of medication (Ross & Crook, 1998), intellectual disability or mobility impairments that restrain grocery shopping and food preparation (Tsai et al., 2011), as well as financial strain as a result of unemployment 465
Nutrient intake and disability
(Turner, 1995). Given these common barriers among persons with disabilities, poor diet quality and insufficient nutrient intake may have an even more detrimental impact on their health in the process of ageing. In the US and worldwide, the rise in noncommunicable diseases and years lived with potentially disabling illnesses and injuries calls for adequate nutrition for persons with disabilities, whereas the relationship between disability and dietary intake has largely been overlooked and the relevant literature remains scarce (Groce et al., 2013). Existing studies often focus on a particular gender, age or residential group using nonrepresentative samples, which confines the generalisability of findings (Sharkey et al., 2003; Houston et al., 2005; Tomey et al., 2008). There are only two studies that have provided national estimates for dietary intake among the US population with disabilities. Using the National Health and Nutrition Examination Survey (NHANES) 1999–2004 waves, increased selfreported disability in lower extremity mobility and general physical activities was found to be linked to lower Healthy Eating Index scores (Xu et al., 2012). However, the outcome measure and study subjects were restricted to an overall diet index (instead of individual nutrients) and to people aged ≥60 years. An & Chiu (2014) examined the relationship between disability status and vegetable/fruit intake among US adults using the Behavioral Risk Factor Surveillance System 2011 wave. Persons with disabilities were shown to consume vegetable/fruit less frequently than disability-free individuals. The present study examined the relationship between disabilities and nutrient intake among US adults aged ≥20 years using a nationally representative sample from the NHANES 2007–2008 and 2009–2010 waves. Disability is classified into five categories using validated indices. Daily intakes of saturated fat, fibre, cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium and potassium from food and dietary supplements were calculated from two consecutive 24-h dietary recalls. Adherence to recommended daily nutrient intake levels between persons with and without disability and across disability categories was examined in bivariate and multivariate analyses, accounting for the NHANES multiyear complex sampling design. Materials and methods Participants Individual-level data originated from NHANES 2007– 2008 and 2009–2010 waves. NHANES is a programme of studies designed to assess the health and nutritional status of adults and children and represents a multistage probability sample of the US civilian, noninstitutionalised population. The NHANES programme began in the early 1960s and periodically conducted separate surveys focus466
R. An et al.
ing on different population groups or health topics. From 1999 onward, NHANES has been conducted continuously in 2-year cycles and has a changing focus on a variety of health and nutrition measurements. Except for the NHANES 1999–2000 wave where all respondents were asked to complete a single 24-h dietary recall interview, all subsequent waves incorporate two dietary recalls, with the first collected in-person and the second by telephone, 3–10 days later. In both interviews, each food item and corresponding quantity consumed by a respondent from midnight to midnight on the day before the interview was recorded. The in-person dietary recall was conducted by trained dietary interviewers in the Mobile Examination Center (MEC) with a standard set of measuring guides. These tools aimed to help the respondent accurately report the volume and dimensions of the food items consumed. Upon completion of the in-person interview, participants were provided measuring cups, spoons, a ruler and a food model booklet, which contained two-dimensional drawings of the various measuring guides available in the MEC for use when reporting dietary intake during the telephone interview. Detailed information on the NHANES protocols are provided on its web portal (http://www.cdc.gov/nchs/nhanes.htm). From 1999–2006, the dietary interviews only asked about food and beverages consumed, and estimating total nutrient intakes from all sources (foods, beverages, and dietary supplements) had been difficult as a result of the different data collection methods, referent time frames and data formats. Beginning in 2007, data were collected on the usage of all vitamins, minerals, herbals and other dietary supplements as part of the dietary interviews (so that, for both dietary recall days, information on food as well as diet supplement is obtained for survey participants). Data on dietary supplement use include supplement type, brand name and quantity consumed. With these data collected using similar methods over the same time frame, nutrients from all sources can be readily combined, which allows researchers to improve total nutrient intake estimations and increases their abilities to estimate percentages of the population with intakes above or below nutrient standards (Centers for Disease Control & Prevention, 2010). The body weight and stature height of NHANES respondents were measured using a digital scale and stadiometer in the MEC. Specific anthropometry procedures apply to wheelchair users, amputees and people with comprehension or language difficulties (Centers for Disease Control & Prevention, 2009b). Body mass index (BMI) is defined as kg m–2. Sociodemographic factors including sex, age, race/ethnicity, marital status, education, and household income were collected through in-person interview. Among the 12 153 adults aged ª 2014 The British Dietetic Association Ltd.
R. An et al.
≥20 years who participated in NHANES 2007–2008 and 2009–2010 waves, 342 were pregnant or were following a special diet, with the aim of losing weight, at the time of interview and were excluded from the the analysis. This resulted in a total effective sample of 11 811. The present study is entirely based upon the de-identified public-use datasets from the NHANES, and thus is exempted from ethnical approval. Disability status In NHANES 2007–2008 and 2009–2010 waves, 19 validated questions were administered to assess five domains of disability: activities of daily living (ADLs), instrumental activities of daily living (IADLs), leisure and social activities (LSAs), lower extremity mobility (LEM) and general physical activities (GPAs). Each question item evaluated the difficulty an individual had in performing a task without the aid of any equipment, and participants were required to choose from among four difficulty levels: ‘no difficulty’, ‘some difficulty’, ‘much difficulty’ and ‘unable to do’. ADLs consist of four activities: dressing oneself; walking between rooms on the same floor; getting in and out of bed; and using a fork, knife and drinking from a cup. IADLs consist of three activities: managing money; doing household chores; and preparing meals. LSAs consist of three activities: going out to movies and events; attending social events; and performing leisure activities at home. LEM consists of two activities: walking a quarter mile and walking up 10 steps. GPAs consist of seven activities: stooping, crouching and kneeling; lifting and carrying; standing up from an armless chair; standing for long periods; sitting for long periods; reaching up over one’s head; and grasping/ holding small objects. Disability is defined as any difficulty in performing at least one of the activities within a given domain. A participant may qualify for more than one disability category, and individuals with no disability refer to those with no difficulty in performing any activities within any of the five disability domains. Five dichotomous variables for ADLs, LSAs, IADLs, LEM and GPAs conditions were constructed, with no disability as their common reference group. Among the total effective sample of 11811, there are 1646, 2266, 1728, 1451 and 3854 participants who reported having ADLs, IADLs, LSAs, LEM and GPAs (not mutually exclusive because it is possible to qualify for multiple disability categories), respectively, whereas 7595 participants had no self-reported disability. Nutrient intake The present study focused on the daily intake of 10 nutrients (saturated fat, dietary fibre, dietary cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium ª 2014 The British Dietetic Association Ltd.
Nutrient intake and disability
and potassium) that are of major public health concern. The Dietary Guidelines for Americans, 2010 (US Department of Agriculture & US Department of Health & Human Services, 2010) cautioned against the low intake of dietary fibre, vitamin D, calcium, iron (especially for women capable of becoming pregnant) and potassium for both adults and children. The Guidelines also identified an excessive intake of saturated fat, dietary cholesterol and sodium in the general population and recommended substantial reduction. The concern regarding insufficient intake of vitamin A and vitamin C appears to have lessened over time but remains. Daily total intake of saturated fat, fibre, cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium and potassium were determined by averaging data from the in-person and telephone interviews, and were separated by daily nutrient intakes from foods only and intakes from both foods and dietary supplements. Daily total energy intake was calculated based on the consumed quantities (g) of carbohydrate, fat, protein and alcohol. Table 1 summarises the recommended daily nutrient intake levels specified in the reference daily intakes (RDIs) (Institute of Medicine, 2011) and the Dietary Guidelines for Americans (US Department of Agriculture & US Department of Health & Human Services, 2010). The RDIs are reference values that are quantitative estimates of nutrient intakes to be used for planning and assessing diets for healthy people. In the RDIs, the estimated average requirement (EAR) is the average daily nutrient intake level estimated to meet the requirement of half the healthy individuals in a particular life stage and gender group, and the tolerable upper intake level (UL) is the highest quantity of daily nutrient intake that is unlikely to pose any health risk to almost the entire population. Adherence to the recommended daily nutrient intake level is defined as daily intake of a nutrient at or above its specific EAR (or dietaryguidelines-recommended level) but below the UL. Individual characteristics Several individual characteristics were controlled for in the multivariate analysis: a dichotomous variable for female (male in the reference group), a continuous variable for age in years, an interaction term between age and female (a product of these two variables), three dichotomous variables for race/ethnicity (Non-Hispanic African American, Non-Hispanic other race or multi-race, and Hispanic, with Non-Hispanic White in the reference group), a continuous variable for BMI, a dichotomous variable for college education (high school education or lower in the reference group), two dichotomous variables for marital status (divorced or separated or widowed, and never married, with married in the reference group), 467
R. An et al.
Nutrient intake and disability Table 1 Recommended daily nutrient intake levels
Nutrient (units) Calories from saturated fat (%) Fibre (g) Cholesterol (mg) Vitamin A (mcg) Vitamin C (mg) Vitamin D (mcg) Calcium (mg) Iron (mg) Sodium (mg) Potassium (mg)
Source of goal
Female 19–30 years
Male 19–30 years
Female 31–50 years
Male 31–50 years
Female 51–70 years
Male 51–70 years
Female ≥71 years
Male ≥71 years
DG
