Investigation of Serum Glucose, Insulin, and Antioxidant Enzyme Activities Among Urban and Rural Adults in Ilorin, Kwara State

Investigation of Serum Glucose, Insulin, and Antioxidant Enzyme Activities Among Urban and Rural Adults in Ilorin, Kwara State

ABSTRACT

Urbanization has transformed dietary habits, lifestyles, and metabolic health patterns across Nigeria. As more people migrate to cities, differences in biochemical parameters between urban and rural populations have become more evident. This study investigates the serum glucose, insulin, and antioxidant enzyme activities among adults residing in urban and rural areas of Ilorin, Kwara State.

Blood samples were collected from consenting participants in both populations. Serum glucose and insulin levels were measured using enzymatic and immunoassay methods, while antioxidant enzyme activities—superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx)—were determined spectrophotometrically. Lifestyle information, including diet and physical activity, was also obtained through structured questionnaires.

Findings revealed higher fasting glucose and insulin levels among urban residents compared to rural participants. Conversely, antioxidant enzyme activities were significantly lower in the urban group, indicating greater oxidative stress. The results suggest that urban lifestyles, characterized by sedentary habits and processed food consumption, may contribute to early metabolic alterations. Encouraging healthier dietary choices and physical activity could reduce metabolic risks and oxidative stress among urban adults.

Keywords: Serum glucose, Insulin, Antioxidant enzymes, Urbanization, Oxidative stress, Ilorin

CHAPTER ONE

1.0 Introduction

Urbanization and changing lifestyles have greatly influenced human metabolic health. In Nigeria, rapid urban growth has led to shifts from traditional diets rich in fiber to energy-dense meals high in fats and refined carbohydrates. This dietary transition, coupled with reduced physical activity, has been linked to metabolic disorders such as obesity, insulin resistance, and type 2 diabetes. Investigating biochemical indicators like glucose, insulin, and antioxidant enzymes provides insight into how environmental and lifestyle factors affect metabolic balance.

Kwara State, with Ilorin as its capital, presents a unique opportunity to study urban–rural biochemical differences. While urban residents often experience higher stress and dietary imbalances, rural dwellers generally maintain more active lifestyles and consume less-processed foods. By comparing biochemical parameters in both groups, this research aims to uncover how lifestyle variations influence metabolic and oxidative health.

1.1 Statement of the Problem

Metabolic disorders are increasingly common in Nigeria’s urban centers, yet there is limited biochemical evidence comparing urban and rural populations in Kwara State. Many adults are unaware of their metabolic health status until symptoms appear. The lack of comparative biochemical data on glucose, insulin, and antioxidant enzymes has hindered preventive strategies and health awareness programs. Understanding these differences can guide interventions to reduce non-communicable diseases among adults in Ilorin.

1.2 Aim and Objectives of the Study

Aim:
To investigate serum glucose, insulin, and antioxidant enzyme activities among urban and rural adults in Ilorin, Kwara State.

Objectives:

1. Determine fasting serum glucose and insulin concentrations in urban and rural adults.

2. Evaluate antioxidant enzyme activities (SOD, CAT, and GPx) in both populations.

3. Compare biochemical differences between urban and rural groups.

4. Examine lifestyle factors that may influence glucose metabolism and oxidative balance.

5. Provide recommendations for improving metabolic and oxidative health among adults.

1.3 Research Questions

1. How do serum glucose and insulin levels differ between urban and rural adults in Ilorin?

2. What are the variations in antioxidant enzyme activities between the two groups?

3. How do dietary habits and lifestyle behaviors influence these biochemical parameters?

4. Are urban adults at greater risk of oxidative stress than their rural counterparts?

1.4 Research Hypotheses

• H₀₁: There is no significant difference in serum glucose and insulin levels between urban and rural adults in Ilorin.

• H₁₁: There is a significant difference in serum glucose and insulin levels between urban and rural adults in Ilorin.

• H₀₂: Antioxidant enzyme activities do not differ significantly between the two populations.

• H₁₂: Antioxidant enzyme activities differ significantly between urban and rural adults.

1.5 Significance of the Study

This study provides biochemical evidence on how urban and rural lifestyles affect metabolic and oxidative health in Kwara State. It contributes to public health awareness by highlighting the impact of diet, stress, and physical activity on glucose regulation and antioxidant defense. The findings will also help policymakers design nutrition and lifestyle interventions to prevent non-communicable diseases such as diabetes and cardiovascular disorders.

1.6 Scope of the Study

The study covers adult males and females aged 25–55 years living in selected urban and rural communities in Ilorin, Kwara State. It focuses on serum glucose, insulin, and antioxidant enzymes (SOD, CAT, GPx). The study excludes individuals with diagnosed metabolic or chronic diseases to ensure reliable baseline comparisons.

1.7 Definition of Terms

• Serum Glucose: The concentration of glucose present in the blood after fasting, used to assess carbohydrate metabolism.

• Insulin: A hormone secreted by the pancreas that regulates blood sugar levels.

• Antioxidant Enzymes: Biological molecules such as superoxide dismutase, catalase, and glutathione peroxidase that protect cells from oxidative stress.

• Oxidative Stress: An imbalance between reactive oxygen species and antioxidant defenses.

• Urbanization: The shift from rural living to city-based lifestyles characterized by reduced physical activity and dietary changes.

CHAPTER TWO

2.0 Literature Review

2.1 Concept of Urbanization and Health Transition

Urbanization has introduced profound changes in diet, work patterns, and physical activity. According to the World Health Organization (WHO, 2022), urban residents often consume diets high in sugar, fats, and processed foods, increasing the risk of obesity and metabolic disorders. Conversely, rural populations tend to maintain traditional diets that support better metabolic health. This urban–rural disparity has become a growing concern in sub-Saharan Africa.

2.2 Glucose and Insulin as Metabolic Indicators

Glucose serves as the primary energy source for body tissues, while insulin facilitates glucose uptake into cells. Elevated serum glucose and insulin levels reflect impaired glucose tolerance or insulin resistance, early indicators of diabetes. Studies have shown that urban adults typically exhibit higher fasting glucose and insulin concentrations compared to rural populations due to sedentary behavior and calorie-rich diets (Olatunji et al., 2021).

Excess insulin levels, known as hyperinsulinemia, can precede the onset of type 2 diabetes. Monitoring these biochemical markers is therefore crucial for early detection of metabolic imbalances.

2.3 Oxidative Stress and Antioxidant Enzyme Activities

Oxidative stress occurs when reactive oxygen species (ROS) exceed the body’s antioxidant defenses. Key antioxidant enzymes—SOD, CAT, and GPx—neutralize ROS and protect tissues from oxidative damage. Inadequate antioxidant enzyme activity contributes to cellular aging, inflammation, and metabolic disorders.

Urban exposure to pollutants, poor dietary antioxidants, and psychological stress can lower antioxidant enzyme levels, increasing oxidative damage. In contrast, rural diets rich in natural fruits and vegetables may enhance antioxidant defense (Adebayo & Hassan, 2020).

2.4 Urban vs Rural Differences in Biochemical Health

Several comparative studies reveal that urban populations face higher risks of metabolic syndrome and oxidative stress than rural dwellers. Factors such as environmental pollution, reduced physical activity, and processed food consumption contribute significantly to this difference. Rural residents, often engaged in farming and manual labor, maintain higher energy expenditure and consume less-refined foods, which support healthier glucose-insulin dynamics.

2.5 Relationship Between Insulin Resistance and Oxidative Stress

Oxidative stress and insulin resistance share a close physiological link. Increased ROS levels can impair insulin signaling pathways, reducing glucose uptake and promoting hyperglycemia. Meanwhile, elevated glucose can further enhance ROS production, creating a damaging feedback loop. Maintaining antioxidant enzyme balance therefore helps preserve normal glucose metabolism (Gutteridge & Halliwell, 2018).

2.6 Socioeconomic and Lifestyle Factors in Kwara State

In Ilorin, rapid urban expansion has led to shifts in occupational and dietary behaviors. Urban adults are more likely to consume fast foods, experience higher stress levels, and engage in less physical activity. Rural communities still rely on subsistence agriculture, leading to higher fiber intake and more active daily routines. These differences justify comparing the biochemical parameters across both populations.

2.7 Theoretical Framework

This study is guided by the Oxidative Stress Theory of Disease, which suggests that oxidative imbalance contributes to chronic metabolic disorders. The theory integrates metabolic and environmental influences, supporting the hypothesis that antioxidant enzyme levels modulate disease risk associated with glucose and insulin imbalance.

2.8 Gaps in Literature

Despite increasing evidence of metabolic disorders in Nigeria, limited research has compared biochemical parameters between urban and rural adults in Kwara State. Most existing studies emphasize dietary surveys or self-reported data without laboratory-based biochemical assessments. This study fills that gap by integrating metabolic and oxidative stress markers.

2.9 Summary

Biochemical evaluation of glucose, insulin, and antioxidant enzymes offers a comprehensive approach to understanding metabolic health differences between urban and rural populations. By investigating adults in Ilorin, this study aims to provide evidence-based insight into how lifestyle and environmental factors shape biochemical health outcomes.