Evaluation of Micronutrient (Iron, Zinc, Selenium) Status and Biochemical Oxidative Stress Markers in Adolescent Girls in Kaduna

Evaluation of Micronutrient (Iron, Zinc, Selenium) Status and Biochemical Oxidative Stress Markers in Adolescent Girls in Kaduna

ABSTRACT

Micronutrients play crucial roles in maintaining metabolic and physiological balance, particularly during adolescence—a stage characterized by rapid growth and hormonal changes. Deficiencies in trace elements such as iron, zinc, and selenium can impair immune response, enzyme function, and antioxidant defense, leading to oxidative stress. This study evaluated the micronutrient status and oxidative stress markers in adolescent girls residing in Kaduna, Nigeria. Blood samples were collected and analyzed for serum levels of iron, zinc, and selenium using atomic absorption spectrophotometry. Oxidative stress parameters, including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), were also determined. The findings revealed significantly reduced levels of these micronutrients among the participants compared to established reference values. Moreover, elevated MDA concentrations and decreased antioxidant enzyme activities suggested the presence of oxidative stress. The results indicate that micronutrient deficiencies contribute to oxidative imbalance in adolescent girls, emphasizing the need for improved nutrition and supplementation programs.

Keywords: Micronutrients, Iron, Zinc, Selenium, Oxidative stress, Adolescent girls, Kaduna.

CHAPTER ONE

1.0 Introduction

Adolescence represents a critical developmental stage marked by rapid growth, hormonal transitions, and increased nutritional demands. Adequate intake of essential micronutrients—especially iron, zinc, and selenium—is vital for maintaining optimal health during this period. Unfortunately, dietary deficiencies are common among adolescent girls in developing countries, often leading to anemia, immune dysfunction, and oxidative stress-related disorders.

Micronutrients such as iron, zinc, and selenium perform important biochemical functions. Iron supports hemoglobin synthesis and oxygen transport; zinc acts as a cofactor in numerous enzymatic reactions, including DNA synthesis and immune modulation; while selenium plays a major role in antioxidant defense through selenoproteins such as glutathione peroxidase. Deficiency in any of these trace elements can impair cellular metabolism and increase vulnerability to oxidative stress.

In Kaduna State, nutritional inadequacies are influenced by poor dietary diversity, limited access to nutrient-rich foods, and socio-economic factors. Adolescent girls are particularly at risk because of increased iron loss during menstruation and their tendency to consume calorie-dense but nutrient-poor diets. Moreover, oxidative stress—caused by an imbalance between free radicals and antioxidants—may further worsen micronutrient deficiency and affect overall wellbeing.

1.1 Statement of the Problem

Several studies have highlighted the prevalence of micronutrient deficiencies among adolescents in Nigeria. However, limited data exist on the biochemical relationship between micronutrient levels and oxidative stress among adolescent girls in Kaduna. Many girls experience fatigue, frequent illness, or poor academic performance, which may be linked to nutritional deficiencies. Without proper evaluation, these biochemical imbalances could persist and predispose them to chronic diseases later in life.

1.2 Aim and Objectives of the Study

The main aim of this study is to evaluate the micronutrient status (iron, zinc, and selenium) and oxidative stress markers among adolescent girls in Kaduna State.

The specific objectives are to:

1. Determine serum levels of iron, zinc, and selenium among adolescent girls.

2. Assess oxidative stress markers such as malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx).

3. Examine the relationship between micronutrient levels and oxidative stress parameters.

4. Provide recommendations to improve micronutrient intake and oxidative balance among adolescent girls.

1.3 Research Questions

1. What are the serum concentrations of iron, zinc, and selenium among adolescent girls in Kaduna?

2. How do oxidative stress markers vary with micronutrient levels?

3. Is there a significant relationship between trace element deficiency and oxidative imbalance in adolescents?

1.4 Research Hypotheses

• H₀₁: There is no significant difference between the observed and reference levels of micronutrients among adolescent girls.

• H₀₂: Micronutrient deficiency has no significant effect on oxidative stress marker levels.

1.5 Significance of the Study

This research provides valuable insights into the nutritional and biochemical health of adolescent girls in Kaduna. The findings will help health professionals design targeted nutrition programs to combat micronutrient deficiencies and oxidative stress. Furthermore, policymakers can use the results to improve adolescent health interventions and promote dietary diversification in schools and communities.

1.6 Scope and Limitation of the Study

The study focuses on adolescent girls aged 10–19 years in selected secondary schools in Kaduna. It assesses serum micronutrients (iron, zinc, selenium) and oxidative stress parameters (MDA, SOD, CAT, GPx). Limitations include possible dietary recall bias, small sample size, and lack of longitudinal data on dietary intake patterns.

1.7 Operational Definition of Terms

• Micronutrients: Essential trace elements required in small quantities for normal physiological functions.

• Oxidative Stress: A condition caused by an imbalance between the generation of free radicals and antioxidant defenses.

• Antioxidant Enzymes: Biological molecules that neutralize reactive oxygen species and protect cells from damage.

• Malondialdehyde (MDA): A byproduct of lipid peroxidation used as an indicator of oxidative stress.

CHAPTER TWO

2.0 Literature Review

This chapter reviews existing research related to micronutrient status, oxidative stress, and their interrelationship in adolescent health. It presents findings from both local and international studies and identifies research gaps addressed by the present work.

2.1 Importance of Micronutrients in Human Health

Micronutrients, though required in small amounts, are indispensable for normal growth, metabolism, and immune function. Iron is crucial for hemoglobin formation and energy metabolism; zinc supports wound healing, protein synthesis, and cell division; while selenium contributes to antioxidant protection and thyroid regulation. According to WHO (2020), deficiencies in these nutrients are major public health issues in developing countries, especially among children and adolescents.

2.2 Micronutrient Deficiency among Adolescents

Adolescents face unique nutritional challenges due to rapid physical and psychological changes. Iron deficiency leads to anemia and fatigue; zinc deficiency causes impaired growth and immune dysfunction; and selenium deficiency may reduce antioxidant defense. Studies by Afolabi et al. (2021) revealed that over 40% of adolescent girls in northern Nigeria have low serum iron and zinc levels. The situation is worsened by poor dietary habits and socio-economic constraints that limit access to balanced diets.

2.3 Role of Micronutrients in Antioxidant Defense

Iron, zinc, and selenium are integral components of antioxidant enzymes. Zinc acts as a cofactor for superoxide dismutase (SOD), which converts superoxide radicals into hydrogen peroxide. Selenium forms part of glutathione peroxidase (GPx), which reduces hydrogen peroxide to water. Adequate micronutrient levels strengthen antioxidant capacity, reducing cellular damage caused by reactive oxygen species (ROS). Nwosu et al. (2022) reported a positive correlation between zinc and SOD activity among Nigerian adolescents, suggesting the vital link between trace elements and oxidative balance.

2.4 Oxidative Stress and Its Biochemical Markers

Oxidative stress occurs when the generation of ROS surpasses the antioxidant defense capacity of cells. Malondialdehyde (MDA), a product of lipid peroxidation, is commonly used as a marker of oxidative damage. Antioxidant enzymes such as SOD, CAT, and GPx counteract oxidative injury. When micronutrient levels fall, these enzymes lose efficiency, allowing ROS accumulation. This imbalance contributes to fatigue, inflammation, and metabolic disorders in adolescents.

2.5 Factors Influencing Micronutrient Deficiency in Kaduna

Several factors contribute to micronutrient deficiencies among adolescent girls in Kaduna. Poor dietary diversity, early menstruation, and inadequate intake of fruits, vegetables, and animal protein play significant roles. Additionally, cultural food restrictions and economic challenges exacerbate the problem. Environmental factors, such as soil nutrient depletion, can also affect the micronutrient content of local produce, thereby influencing dietary quality.

2.6 Interrelationship Between Micronutrients and Oxidative Stress

Micronutrient deficiency and oxidative stress are interlinked. Insufficient iron, zinc, and selenium levels weaken enzymatic antioxidant systems, leading to oxidative damage. Conversely, oxidative stress can further deplete micronutrients by increasing their utilization in detoxification processes. Oladipo et al. (2023) demonstrated that adolescents with low micronutrient levels exhibited elevated MDA and reduced SOD and CAT activities, confirming this bidirectional relationship.

2.7 Health Consequences of Micronutrient Deficiency

Prolonged micronutrient deficiencies can lead to serious health problems such as anemia, stunted growth, cognitive decline, and weakened immunity. For adolescent girls, these deficiencies may also cause menstrual irregularities and complications during future pregnancies. Addressing these issues through balanced diets, fortification, and supplementation can significantly improve long-term health outcomes.

2.8 Research Gaps

While several studies have examined general nutrition in adolescents, few have explored the combined evaluation of micronutrients and oxidative stress markers in Kaduna. There is a need for region-specific biochemical data to understand how nutritional deficiencies affect oxidative status in this demographic.

2.9 Summary of Literature Review

Micronutrients are critical for maintaining antioxidant balance and preventing oxidative stress. Deficiencies in iron, zinc, and selenium compromise enzymatic activity and promote cellular damage. Understanding their biochemical interplay in adolescent girls will aid in developing interventions to combat malnutrition and oxidative-related disorders in Kaduna State.