Project – Dietary Habits, Physical Activity and Risk of Type 2 Diabetes among Adults: A Study of Residents of Selected Communities in Abeokuta South LGA, Ogun State.

CHAPTER ONE

INTRODUCTION

1.1 Background to the Study

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterised by persistent elevation of blood glucose resulting from impaired insulin secretion, insulin resistance, or a combination of both. Unlike type 1 diabetes, which is primarily associated with autoimmune destruction of pancreatic beta cells, type 2 diabetes is strongly influenced by a combination of genetic, environmental, behavioural and metabolic factors. The disease has become a major public-health concern because of its increasing occurrence among adults and its association with serious complications such as cardiovascular disease, kidney failure, blindness, neuropathy and lower-limb amputation. The World Health Organization (WHO, 2024) reported that the number of people living with diabetes globally increased from about 200 million in 1990 to 830 million in 2022, with the increase occurring particularly rapidly in low- and middle-income countries. The WHO further identifies unhealthy diet, insufficient physical activity and excess body weight as important modifiable factors in the prevention of type 2 diabetes.

The growing burden of diabetes has also become particularly important in Africa, where demographic transition, urbanisation, changing food environments and lifestyle changes are occurring alongside limited capacity for chronic disease prevention and management. The International Diabetes Federation (IDF, 2025) estimated that approximately 24.6 million adults aged 20–79 years were living with diabetes in the African region in 2024, with approximately 73% of cases estimated to be undiagnosed. For Nigeria, the IDF estimated about 2.99 million adults aged 20–79 years living with diabetes in 2024 and projected this figure to increase substantially by 2050 if current trends continue. These estimates demonstrate the increasing importance of diabetes prevention in Nigerian communities and reinforce the need to investigate modifiable behavioural factors such as dietary habits and physical activity at the local level (International Diabetes Federation [IDF], 2025).

Nigeria has experienced a considerable burden of diabetes, with evidence indicating that the disease affects adults across different geographical and socioeconomic groups. A systematic review and meta-analysis of diabetes mellitus in Nigeria estimated a pooled prevalence of 5.77%, with a higher pooled prevalence of 5.5% reported for the South-West geopolitical zone (Uloko et al., 2018). More recent evidence focusing specifically on type 2 diabetes found a pooled national prevalence of approximately 7.0% from 60 studies involving 124,876 participants, while significant associations were identified with physical inactivity, urban residence, elevated body mass index, abdominal obesity, infrequent vegetable consumption and family history of diabetes (2024). These findings are particularly relevant to an urban local government such as Abeokuta South, where changes in food consumption, transportation, occupation and recreational patterns may influence exposure to behavioural risk factors for T2DM.

Dietary behaviour is an important component of the development and prevention of type 2 diabetes. Diets characterised by excessive energy intake, high consumption of refined carbohydrates, free sugars, saturated fats and highly processed foods may contribute to weight gain, insulin resistance and metabolic abnormalities, particularly when combined with inadequate consumption of fibre-rich foods, fruits and vegetables. The WHO (2026) emphasises that healthy diets should be based on adequacy, balance, moderation and diversity, with minimally processed or unprocessed foods forming an important part of dietary intake. The organisation also notes that rapid urbanisation and changing food systems have contributed to greater consumption of highly processed foods containing unhealthy fats, free sugars and sodium, while many populations consume inadequate quantities of fruits, vegetables and dietary fibre. Among Nigerian adults, research examining dietary patterns in Southwestern Nigeria has similarly demonstrated the importance of assessing locally consumed food groups and meal patterns when investigating nutritional and metabolic health (WHO, 2026; 2024).

Physical activity is another major modifiable factor associated with the development of type 2 diabetes. Regular physical activity improves glucose utilisation, supports healthy body weight, improves insulin sensitivity and contributes to the prevention of several non-communicable diseases. Conversely, prolonged sedentary behaviour and insufficient physical activity can increase the risk of metabolic disorders. The WHO (2024) recommends that adults undertake at least 150 minutes of moderate-intensity physical activity per week, or an equivalent combination of moderate- and vigorous-intensity activity. Evidence from Nigeria also demonstrates the relevance of physical activity to diabetes: a systematic review of Nigerian studies identified physical inactivity as a significant risk factor for T2DM, while research among Nigerian adults with type 2 diabetes found substantial levels of physical inactivity and sedentary behaviour (WHO, 2024; 2024). Therefore, examining physical activity among adults in selected communities in Abeokuta South LGA is important for understanding behavioural exposure that may contribute to diabetes risk.

Evidence from Ogun State provides a particularly important basis for examining diabetes risk at community level. A large community-based diabetes risk assessment conducted across 25 communities in Ogun State involved 58,657 respondents and found that 19.2% were obese and 28.9% were overweight according to BMI. The study also identified 5.05% of the participants as having diabetes based on the glucose criteria used in the investigation and found a substantial proportion of participants at increased risk of developing diabetes within 10 years according to the Finnish Diabetes Risk Score (Odenigbo et al., 2013). More recent evidence from communities in Ogun State has also reported both known and newly diagnosed diabetes as well as prediabetes among adults screened through a community-based programme (Ale et al., 2026). These findings indicate that diabetes and its precursor conditions are present within Ogun communities and support the importance of investigating behavioural risk factors before the development of established disease.

Abeokuta-specific evidence further demonstrates the relevance of diabetes research in the proposed study area. A community screening study conducted in Abeokuta examined 182 adults from three communities and identified individuals with elevated glucose levels, with prevalence varying by sex and age group (Akinjinmi et al., 2014). In another study among civil servants in Abeokuta Town, diabetes was associated with BMI, blood pressure and family history, while age, BMI, family history and cigarette smoking were identified as significant factors in logistic regression analysis; the study also observed that physical exercise was inadequately practised among the study participants (Tropical Journal of Medical Research, 2022). Although these studies do not establish the exact prevalence or risk-factor distribution among all residents of Abeokuta South LGA, they provide evidence that diabetes and related risk factors are relevant within the Abeokuta population. Consequently, examining dietary habits and physical activity among adults in selected communities in Abeokuta South LGA may provide useful community-level evidence concerning behavioural factors associated with T2DM risk.

The relationship between dietary habits, physical activity and type 2 diabetes is therefore important because these behaviours interact with other factors such as age, family history, obesity, socioeconomic circumstances and urban living. A person may have a genetic predisposition to diabetes but may also experience increased risk through a combination of unhealthy dietary practices, inadequate physical activity and excess body weight. The Nigerian systematic review and meta-analysis reported significant associations between T2DM and physical inactivity, BMI above 25 kg/m², abdominal obesity, urban residence, infrequent vegetable consumption and family history (2024). Similarly, the WHO (2024) recognises healthy diet, regular physical activity and maintenance of a healthy body weight as important approaches for preventing or delaying type 2 diabetes. Investigating these factors among adults in selected communities in Abeokuta South LGA is therefore justified because community-specific information can help identify behavioural patterns that may be relevant to diabetes prevention and health promotion.

The prevention of type 2 diabetes increasingly requires attention to population-level behavioural patterns rather than relying exclusively on treatment after diagnosis. Since many of the major determinants of T2DM are modifiable, community-based interventions can focus on promoting healthier food choices, regular physical activity, healthy body weight and early identification of individuals at elevated risk. The WHO (2024) notes that type 2 diabetes can often be prevented or delayed through lifestyle changes, while the IDF (2025) emphasises the growing global and national burden of diabetes and the need for effective prevention strategies. In Nigeria, the evidence from Ogun State and Abeokuta indicates that diabetes risk factors are already present within local populations (Odenigbo et al., 2013; Akinjinmi et al., 2014). The present study therefore focuses specifically on dietary habits, physical activity and risk of type 2 diabetes among adults in selected communities in Abeokuta South Local Government Area, Ogun State, with the intention of generating evidence that can contribute to community health education, risk assessment and preventive interventions.

1.2 Statement of the Problem

Type 2 diabetes mellitus is increasingly recognised as a major public-health challenge because of its rising prevalence, long-term complications and substantial economic and social consequences. Globally, the number of people living with diabetes reached approximately 830 million in 2022, while many people remain undiagnosed or untreated. Diabetes can lead to cardiovascular disease, kidney failure, blindness, neuropathy and lower-limb amputation, making prevention and early detection important components of public-health practice (WHO, 2024). The growing burden is particularly concerning in low- and middle-income countries, where health systems must simultaneously address communicable diseases and an increasing burden of non-communicable diseases.

Nigeria is also experiencing an increasing burden of type 2 diabetes. A recent systematic review and meta-analysis involving 60 Nigerian studies and 124,876 participants estimated a pooled T2DM prevalence of 7.0% and identified physical inactivity, urban living, BMI above 25 kg/m², abdominal obesity, infrequent vegetable consumption and family history among significant risk factors (2024). The IDF (2025) additionally estimated that approximately 2.99 million Nigerian adults aged 20–79 years were living with diabetes in 2024, with the number projected to increase substantially by 2050. These findings indicate that diabetes prevention cannot be restricted to clinical management of already diagnosed patients; attention is also required at community level to identify behavioural and lifestyle factors that may increase the likelihood of developing the disease.

The problem is particularly relevant in Ogun State and Abeokuta. A large community-based risk assessment conducted across 25 communities in Ogun State found substantial levels of overweight and obesity and identified more than five percent of screened participants as having diabetes according to the study’s glucose criteria (Odenigbo et al., 2013). In Abeokuta, previous community screening also identified diabetes among adults, while a study of civil servants in Abeokuta Town found significant relationships between diabetes and factors including BMI, family history and other characteristics (Akinjinmi et al., 2014; Tropical Journal of Medical Research, 2022). More recent community screening evidence from Ogun State has continued to demonstrate the presence of diabetes, newly diagnosed cases and prediabetes (Ale et al., 2026). However, these studies have used different populations and settings, and there remains a need for focused evidence on adults living specifically within selected communities in Abeokuta South LGA.

A further problem concerns the limited availability of community-specific evidence linking dietary habits and physical activity to the risk of type 2 diabetes among adults in Abeokuta South LGA. Although unhealthy diet and physical inactivity are recognised risk factors, the specific behavioural patterns of residents may differ according to occupation, income, food availability, transportation practices, cultural preferences and the physical environment. The WHO (2026) identifies unhealthy dietary patterns and inadequate consumption of nutritious foods as important concerns in the prevention of non-communicable diseases, while WHO (2024) identifies physical inactivity as an important modifiable risk factor for type 2 diabetes. Therefore, determining the dietary habits and physical activity patterns of adults in selected communities in Abeokuta South LGA, and examining their relationship with diabetes risk, is necessary to provide evidence for locally appropriate health-promotion and disease-prevention strategies.

1.3 Purpose of the Study

The main purpose of this study is to examine dietary habits, physical activity and risk of type 2 diabetes among adults in selected communities in Abeokuta South Local Government Area, Ogun State.

The specific objectives are to:

1. assess the dietary habits of adults in selected communities in Abeokuta South LGA;
2. determine the level of physical activity among adults in the selected communities;
3. assess the risk of type 2 diabetes among adults in the study area;
4. determine the relationship between dietary habits and risk of type 2 diabetes among the respondents;

1.4 Research Questions

The following research questions will guide the study:

1. What are the dietary habits of adults in selected communities in Abeokuta South LGA?
2. What is the level of physical activity among adults in the selected communities?
3. What is the level of risk of type 2 diabetes among adults in the study area?
4. What relationship exists between dietary habits and risk of type 2 diabetes among the respondents?

1.5 Research Hypothesis

The following null hypothesis will be tested at 0.05 level of significance:

H₀: There is no statistically significant relationship between dietary habits, physical activity and risk of type 2 diabetes among adults in selected communities in Abeokuta South Local Government Area, Ogun State.

1.6 Significance of the Study

The study will be significant to adults and residents of selected communities in Abeokuta South LGA because it will provide information concerning dietary practices, physical activity and behaviours that may be associated with the risk of type 2 diabetes. The findings may encourage residents to pay greater attention to healthy food choices, regular physical activity and other preventive behaviours.

The study will be useful to public-health practitioners because it will provide community-level evidence concerning behavioural risk factors for type 2 diabetes. Such information can assist health workers in designing appropriate health education and community-based screening programmes.

The study will also be relevant to primary healthcare providers in Abeokuta South LGA. The findings may support the development of routine diabetes-risk assessment, lifestyle counselling, referral and health-promotion activities targeted at adults who demonstrate elevated risk.

The study will be useful to the Ogun State Ministry of Health and Local Government health authorities by providing evidence that may assist in planning non-communicable disease prevention programmes. Information on dietary patterns and physical activity may help health planners identify areas where community health education and lifestyle interventions require greater attention.

The study will also benefit community leaders, health educators and non-governmental organisations working on non-communicable disease prevention. The findings may provide evidence for community sensitisation programmes addressing healthy eating, physical activity, weight management and diabetes-risk reduction.

Finally, the study will contribute to academic and research literature on type 2 diabetes in Nigeria, particularly within Southwestern Nigeria. It may serve as a reference for researchers undertaking subsequent studies on dietary behaviour, physical activity, diabetes risk and other non-communicable diseases in Ogun State and similar urban communities.

1.7 Scope of the Study

The study will focus on dietary habits, physical activity and risk of type 2 diabetes among adults in selected communities in Abeokuta South Local Government Area, Ogun State.

The geographical scope will be restricted to selected communities within Abeokuta South LGA. The population will consist of adults aged 18 years and above who reside in the selected communities and satisfy the inclusion criteria established for the study.

The content scope will cover dietary habits, physical activity and risk of type 2 diabetes. Dietary habits will include selected aspects of food consumption such as frequency of fruit and vegetable intake, consumption of sugary foods and beverages, fried foods, processed foods, meal patterns and other relevant dietary behaviours. Physical activity will include frequency, duration and intensity of physical activities associated with work, transportation, domestic activities and recreation.

The study will assess diabetes risk rather than restrict the investigation to previously diagnosed diabetes. Relevant risk indicators may include age, sex, family history of diabetes, body mass index, waist circumference, physical activity and dietary characteristics. The study will not primarily investigate type 1 diabetes, gestational diabetes or childhood diabetes.

1.8 Operational Definition of Terms

Dietary Habits: The regular patterns of food and beverage consumption of an individual, including the types, frequency and quantity of foods consumed, meal patterns and consumption of fruits, vegetables, sugary foods, processed foods and other relevant dietary components.

Physical Activity: Any bodily movement produced by skeletal muscles that requires energy expenditure, including occupational, transportation-related, domestic and recreational activities.

Type 2 Diabetes Mellitus: A chronic metabolic disease characterised by elevated blood glucose resulting primarily from insulin resistance and inadequate insulin secretion.

Risk of Type 2 Diabetes: The likelihood that an individual may develop type 2 diabetes based on selected demographic, genetic, anthropometric, lifestyle and behavioural characteristics assessed by the study instrument.

Adult: A person aged 18 years and above who resides in one of the selected communities and meets the eligibility criteria for participation.

Healthy Dietary Habit: A dietary pattern characterised by adequate and varied consumption of nutritious foods, including fruits, vegetables, whole grains and legumes, while limiting excessive intake of free sugars, unhealthy fats and highly processed foods.

Unhealthy Dietary Habit: A dietary pattern involving frequent consumption of foods or beverages that may contribute to excessive energy intake or metabolic risk, such as sugary drinks, highly processed foods, excessive fried foods and diets low in fruits, vegetables or dietary fibre.

Physical Inactivity: A level of physical activity that does not meet recommended activity levels for adults.

Body Mass Index (BMI): A measure of body weight relative to height, calculated as weight in kilograms divided by height in metres squared (kg/m²).

Overweight: A body mass index of 25.0–29.9 kg/m² in adults.

Obesity: A body mass index of 30.0 kg/m² or above in adults.

Family History of Diabetes: A respondent’s report that a close biological relative, particularly a parent or sibling, has been diagnosed with diabetes.

Selected Communities: Communities within Abeokuta South Local Government Area that will be selected according to the sampling procedure described in Chapter Three.

Abeokuta South Local Government Area: A Local Government Area in Ogun State, Southwestern Nigeria, and the geographical setting of the present study.

Project – Dietary Habits, Physical Activity and Risk of Type 2 Diabetes among Adults: A Study of Residents of Selected Communities in Abeokuta South LGA, Ogun State.