Amidst reports of health improvements, African Americans living in the United States continue to be disproportionately impacted by chronic disease resulting in higher death rates compared to non-Hispanic whites [1
]. African Americans are 1.4 times as likely to be obese, 1.5 times more likely to have hypertension, and are more than twice as likely to have diabetes or a stroke than their non-Hispanic white counterparts [3
]. This disparity leads to greater reduction in income (due to lost productivity), and higher cost for care in terms of responsibilities and medical expenses. Chronic disease-related expenses cost the nation $
3.3 trillion annually and are expected to increase to $
42 trillion by the year 2030 [8
]. Although chronic diseases are among the most debilitating and costly conditions, they are also among the most preventable.
Poor diet quality is a leading risk factor for chronic diseases and consumption of high quality diets have been associated with significantly lower risk in chronic disease and all-cause mortality [11
]. A high diet quality reflects an eating pattern that includes a variety of vegetables, fruits, whole grains, protein, low fat dairy, and healthy oils, and limited intake of saturated and trans fats, added sugars, and sodium [16
]. A recent systematic review and meta-analysis of prospective studies showed an association between high diet quality and lower risk of cancer and cardiovascular disease incidence and mortality, type 2 diabetes, and neurodegenerative diseases. In addition, high diet quality among cancer survivors was associated with a significant decrease in all-cause mortality [14
]. The improvement in adherence to diet quality was also shown to lower both short and long-term cardiovascular risks [17
Despite these strong associations, few studies have examined diet quality among African American adults [19
]. Instead, the majority of studies have focused on dietary components rather than overall diet quality. Results from these studies indicate that indeed African Americans have lower intakes of dietary fiber and vegetables, whole grains, and dairy, and higher intakes of fat, sodium, and sugar-sweetened beverages [22
]. Although this information adds to the extant literature, it is limiting in that it neither provides a holistic picture of overall diet quality nor of how the diets of African Americans are aligned with the recommendations of the Dietary Guidelines for Americans (DGA). This gap in the literature precludes the use of such empirical evidence by nutrition educators and policy makers in targeted interventions, while also masking diet-related disparities among African Americans. Boggs et al. noted that due to differences in disease incidence and comorbidities, genetic predisposition, and unique modifying factors between ethnic groups, a focus on diet quality among African American is paramount [20
Diet-related disparities are complex, multifaceted, and associated with demographic (age, gender, education, income) and psychosocial (self-efficacy, social support) factors and influences, as well as barriers to healthy eating [26
]. Past research has shown a positive linear association between socioeconomic status (SES) and diet quality [28
]. This relationship is evident even in international populations [30
]. Several studies have also shown that having social support (or positive social influences and encouragement from others to engage in healthy eating) was associated with higher diet quality [31
]. Similarly, self-efficacy has been shown to predict diet quality in different target populations [35
]. Barriers to healthy eating such as cost and finances, availability and convenience, absence of fruits and vegetables in the home, and lack of knowledge regarding healthy foods have also been associated with the diet quality of African Americans [39
Although several studies have examined individuals factors associated with diet-related disparities, few have collectively examined the demographic and psychosocial factors, and barriers to healthy eating with diet quality among African Americans. The majority of studies consisted of mixed populations with results not disaggregated by race, thus making it difficult determine the true effect of these factors on the diet quality of African Americans. The goal of this study was to collectively examine the association of social support, self-efficacy, barriers to healthy eating, and demographic variables with the diet quality of African American adults in order to inform, and tailor future interventions and education and policy efforts.
African American adults have the highest rates of chronic disease, morbidity, and mortality, and generally have the lowest diet quality of all racial groups in the United States [1
]. This study collectively examined demographic (age, gender, education, income) and psychosocial (self-efficacy, social support) factors, barriers to healthy eating, and diet quality among African American adults. Participants had a mean HEI score that was similar to the national average (“needs improvement”) but none had an HEI score in the “good” category. Among the variables examined, barriers to healthy eating was the strongest predictor of diet quality. There was also an interaction between age and barriers so that younger African Americans with the highest barriers had the lowest diet quality. Despite participants’ reports of having social support, high self-efficacy, and low barriers to healthy eating, diet quality was still in the category of needing improvement.
The mean HEI score of participants in this study was similar to the mean HEI score of the United States population. This result differed from previous findings that suggested African Americans had comparatively poorer diet quality [56
]. One reason this sample had a diet quality similar to that of the national average, may be due to their high levels of education. The majority of participants (72%) had either some college or a college degree. Hiza and colleagues examined the diet quality of Americans based on age, sex, race/ethnicity, income, and education levels. They found adults with higher levels of education had higher diet quality scores than adults with lower levels of education [55
]. Additionally, Wilcox et al. examined diet quality among predominantly African American participants and their results also showed poorer diet quality among participants with lower education [28
]. Level of education may have also been associated with the intake of dietary components. For example, Participants consumed a mix of foods and beverages that were significantly lower in refined grains, whole fruit, dairy and protein, and higher in whole grains, greens and beans, total fruit, and fatty acids than the national average. Similar dietary patterns have been observed in populations with higher education. A study by Rehm and colleagues using NHANES data showed that over time (from 1999 to 2012), those with higher education consumed higher amounts of whole grains, whole fruit, and fruit juice compared to those with lower education. Given that the majority of our participants had either some college or a college degree, this could have explained the similarities in mean HEI scores and dietary components with the national sample [57
Previous research has also shown that African Americans consume fewer servings of milk and dairy products and therefore have lower calcium intake [58
]. The role of calcium in the reduction of risk for obesity, hypertension, cardiovascular disease, insulin resistance syndrome, and some types of cancers is well established in the literature [59
]. African Americans and other minority populations tend to be lactose-intolerant, therefore making it difficult to consume dairy products [64
]. Bronner et al. suggested the importance of nutrition education interventions that address the cultural, community, and environmental barriers associated with reduced dairy intake among African Americans [61
]. Participants consumed less whole fruit but more total fruit. Past research has also shown that African Americans tend to consume less whole fruit compared to other racial groups [55
]. It is important to develop strategies to increase the consumption of whole fruit among African Americans as some studies show that 100% fruit juice accounts for approximately one-third of total fruit, which are generally lower in fiber and are source of liquid calories [65
Participants consumed significantly higher amounts of empty calories (subgroups include added sugar, solid fats, and alcohol) than the national average. Major sources of solid fats in the American diet include pizza, grain-based desserts, regular cheese and fatty meats while approximately three-quarters of added sugars originate from sugar-sweetened beverages, snacks, and sweets. Previous research showed African Americans have higher intake of sugar-sweetened beverages, energy from salty snacks, and dessert and sweets [57
]. Kant and Graubard mentioned that non-Hispanic blacks were the only ethnic group that did not show a decrease in per capita energy in the last decade [68
]. Interestingly enough, although participants in this study reported high self-efficacy to engage in healthy eating overall, they also reported having very low self-efficacy with regard to avoiding high fat snacks when in a hurry. This result showed some alignment with the high HEI scores observed for empty calories among participants. This study alludes to the importance of having information on dietary quality as well as the dietary components of particular groups before planning nutrition interventions. Future interventions should target the reduction in sugar-sweetened beverages and all sources of empty calories among African Americans as a means of improving diet quality.
A significant predictor of diet quality in the current study was barriers to healthy eating. This finding was interesting as, on average, participants reported a low number of barriers. Although barriers to healthy eating was associated with poor diet quality among the entire sample, this association was stronger for younger African Americans with the greatest number of barriers. Previous research also indicated that young African American adults have the worst diet quality [69
]. The three most reported barriers to healthy eating in the current study were lack of time to prepare healthy food, cost, and the convenience of fast food restaurants. Similar barriers to healthy eating have been reported in previous research among African American adults [71
]. Studies have shown that reducing barriers to healthy eating, for example making time to prepare a healthy meal, was associated with a higher diet quality, including higher intakes of fruit, vegetables, salads, and fruit juices [73
]. These findings suggest that education in food preparation and time management skills might be needed to alleviate barriers to healthy eating especially among young African Americans.
Additionally, there seems to be a disconnect in the current sample, in that participants reported high levels of self-efficacy and social support for healthy eating but their diet quality was still in the category of poor or needs improvement. Previous studies have showed a similar disconnect [73
]. For example, Pawlak and Colby found that although African Americans reported high self-efficacy to purchase healthy foods, this did not translate to intakes of these foods [73
]. Several possible reasons might be responsible for this discrepancy. First, some African Americans may perceive healthy eating as not being aligned with their cultural heritage [76
]. The emphasis on soul food in African American culture might make engaging in a healthy diet difficult, as these foods are often high in fat and calorie density [68
]. Second, studies have shown that while African Americans may be aware of the benefits of eating healthy, there is a general lack of knowledge regarding dietary guidelines [73
]. For example, in a study comparing the knowledge, attitudes, and beliefs towards healthy foods among African American and Hispanic mothers, African American mothers had comparatively lower knowledge scores related to food groups and dietary recommendations [69
]. Third, it is also quite possible that participants lacked knowledge of what constitutes “low fat”, “high fat snack”, and “healthy” foods. These concepts are polysemous and therefore could have resulted in some discrepancy in self-efficacy [79
This study is not without limitations. The cross-sectional design limits the ability to make conclusions regarding causality. In addition, the sample was from a southeastern metropolitan area thus limiting the generalizability of the results. The use of a convenience sample could also have resulted in under or overrepresentation of particular groups of African Americans. Further, self-reported data were used which are subject to bias and both random and systematic error [35
]. Despite these limitations, several findings of the study were supported by the results of large, representative national samples. The strength of this study was that it collectively examined demographics, psychosocial factors, and barriers to healthy eating associated with diet quality among an African American population, thus adding to the extant literature.
Future research should continue to focus on the complex factors associated with diet quality among African Americans, especially young African Americans. Future interventions should focus on increasing intake of whole fruit and dairy, while reducing the consumption of empty calories. Education on the Dietary Guidelines and its recommendation should be an integral part of these interventions. Qualitative studies are needed to understand the perception, facilitators, barriers, and the potential disconnection between perceived ability and support, and actual diet quality among adult African Americans.