Eating just one egg a day reduces nutritional deficits in US teenagers

U.S. teens face significant nutrient deficiencies, but new research finds that a simple solution—adding one egg a day—can significantly increase their nutrient intake and improve their health, especially for those at risk of food insecurity.

Study: Modeling eating egg-rich diets and adding one egg daily reduced the risk of nutrient deficiencies among food-insecure and non-food-insecure U.S. adolescents. Image Credit: mdbildes/Shutterstock

In a recently published study Nutrition Journal, Researchers in the US analysed data from the US NHANES study to assess the nutritional status of US adolescents and the effects of added egg consumption on observed patterns. Alarmingly, over 60% of adolescents were at risk of deficiency in one or more of the following: calcium, magnesium, choline, and essential vitamins (e.g. vitamins D and E) due to potentially unhealthy eating behaviours (e.g. late-night snacking).

Encouragingly, consuming primarily egg-based meals was found to improve nutritional outcomes, with consumers exhibiting significantly higher levels of choline, vitamin B2, vitamin D, selenium, lutein + zeaxanthin, docosahexaenoic acid, and protein compared to their egg-avoiding peers. These findings highlight the need for policymakers to increase the promotion, accessibility, and availability of eggs and similar nutrient-rich foods to reduce the risk of widespread nutrient deficiencies and address growing concerns of nutritional insecurity at home and abroad.

Background

‘Food insecurity’ – the situation in which individuals or households lack financial or other access to sufficient safe and nutritious food necessary for normal growth and development and for active and healthy living – is a global health concern. The World Health Organization (WHO) estimates that more than 733 million people (~9% of the human population) will experience acute food shortages in 2023, an increase of 152 million in just four years between 2019 and 2023.

While more than 70% of individuals experiencing food insecurity live in underdeveloped and war-torn areas, developed households (like those in the United States) are increasingly affected by inadequate nutrient intake, especially for children and adolescents. In 2022, the Dietary Guidelines for Americans (DGA) reported that 17.3% of households with minors were food insecure. The report highlights that adolescents have the worst eating habits of any human developmental stage, exhibiting poor choices in both dietary decisions (e.g., junk food instead of home-cooked diets) and healthy eating habits (e.g., regular meal times).

Meal plans, including the increasingly popular Thrifty Food Plan (TFP), which aim to balance nutrient adequacy with affordability to meet the Dietary Reference Intake (DRI) recommended for optimal health for adolescents in the United States, have met with limited success. Unfortunately, the lack of clear scientific evidence on the health consequences of accessible, inexpensive foods like eggs has hindered the development of improved meal plans. Identifying the dietary consequences of these food components would provide caregivers and policymakers with the information needed to pave the way for a healthier, safer tomorrow.

“Although meals consisting primarily of eggs (e.g., hard-boiled eggs) are considered protein foods, eggs are also commonly found as ingredients in other types of meals (e.g., burritos), as a component of foods in the cereal group (e.g., breads), and to a lesser extent in some snack foods. This disparate distribution of eggs across food groups presents challenges to understanding their contribution to nutrient intake. Yet eggs provide several additional nutrients that have not yet been evaluated in this context, and few, if any, studies have modeled the effects of adding an egg on habitual nutrient intakes among U.S. adolescents.”

About the work

The current study aims to assess the nutritional contributions of eggs (nutrient exposure scores) to dietary recommendations (DRI, DGA, and Frugal Nutrition Plan) in micronutrient and protein aspects. It also models the potential benefits of adding one egg per day to the diets of former adolescent participants of the NHANES (2007-2018) study.

Data for the study were obtained from the National Health and Nutrition Examination Survey (NHANES), a longitudinal (2007-2018) nationally representative, continuous, cross-sectional database hosted by the U.S. Centers for Disease Control and Prevention (CDC). Data were collected through home-based interviews, health screenings using a mobile screening center (MEC), and follow-up telephone interviews. Data included demographic information (age, gender, weight, height, body mass index). [BMI]family poverty-income ratio (PIR) and race/ethnicity).

“This study included two analytic samples. The first was used to estimate average usual dietary intake and percentage of adolescents not meeting dietary recommendations and included adolescents aged 14–17 years with complete food security data (i.e., household child food security) and ≥1 reliable 24-h dietary recall (n=3,633). The second was used to estimate TNI and FNI scores and included adolescents aged 14–17 years with complete information on dietary supplements (i.e., Dietary Supplement and Prescription Drug Questionnaire (DSMQ)) and at least one 24-h dietary recall (n=1,822).”

Food security was a key variable for which adolescent participants were classified into food insecure and food insecure categories according to the US Household Food Security Survey Module. Dietary data were obtained from NHANES records and MEC analyses. The USDA’s Food and Nutrient Database for Dietary Studies (FNDDS) database was used to classify diets containing eggs as ‘primary egg dishes’ and ‘egg-containing dishes’. Rao-Scott statistical test and t-tests were used to assess the contributions of sociodemographic variables and between-cohort differences, respectively.

Study findings

Supporting the DGA reports, 14% of the current study cohort (ages 14–17) lived in food-insecure households, most of whom were non-Hispanic black or Mexican American. Additionally, participants who were obese (BMI >30) and low income (PIR <1.00) were more likely to belong to food-insecure households. Of concern, nearly half of the study cohort (49%) did not consume eggs at all, while 36% and 15% primarily consumed egg dishes and egg-containing dishes, respectively.

“…regardless of food security status, more than 80% of adolescents were at risk of deficiency for vitamins D and E. Only 9–14% of adolescents had intakes greater than the AI ​​for choline.”

Food secure adolescents who consumed primarily egg-based diets presented significantly better nutritional measures than other groups, particularly in protein and essential micronutrient categories. Modeling the addition of one egg per day to the diet significantly improved nutrient intake across all groups, including those at high risk of nutrient deficiencies. The study found that even food insecure adolescents benefited from egg consumption, particularly in the areas of choline, vitamin D, and protein intake.

Results

Although the United States is a developed country with limited food shortages, over 60% of the current study cohort (n = 5,455) suffered from nutrient deficiencies (especially in proteins and essential micronutrients such as vitamin D, calcium, magnesium, and choline), suggesting that adolescents are a high-risk population in dietary studies.

Almost half of the participants reported rarely or never consuming eggs. Participants who primarily consumed eggs as part of their diet significantly reduced their nutrient deficiencies. Modeling findings revealed that adding one egg per day significantly improved nutrient outcomes across all cohorts evaluated, but participants with food insecurity were expected to benefit the most.

“Efforts to increase the accessibility and availability of nutrient-rich foods are vital to reducing nutritional risk for all adolescents, and more specific strategies may be needed given the prevalence of food and nutrition insecurity.”