The extraction and use of natural resources as raw materials in the built environment for the construction of luxury communities often disrupt the ecosystem, destabilize the soil, displace fauna/flora, and encroach into fertile agricultural spaces. This study investigates the negative effects of built environmental activities, including urbanization, industrialization, and real estate development, on food security in the coastal wetland regions of Epe and Ibeju-Lekki in Lagos, Nigeria. These areas, home to around 299,527 people according to 2006 Census, are rich in natural wetlands suitable for the growth of staple crops such as rice. However, rapid infrastructure development has resulted in ecological degradation, jeopardizing regional food security and weakening key Sustainable Development Goals (SDGs), notably Goals 1, 2, 3, 8, 9, and 11–17. A mixed-methods approach was used, with quantitative data collected by systematic sampling and questionnaires issued to 71 respondents per Local Council Development Area (LCDA), and qualitative data obtained through interviews and field observations. Spatial and statistical analysis was carried out using ArcGIS 10 and SPSS 21. According to the findings, the most prominent built environment activities in the area include the development of residential buildings, industry, transportation infrastructure, and recreational facilities. These developments have led to environmental disruption by displacing wildlife, reducing arable land, and raising food prices. Over 50% of participants noted negative impacts from industrial emergence, such as increased crime and respiratory health issues attributed to air pollution and carbon emissions. The study identifies major socioeconomic and environmental consequences of built environment activities on food security in the area. Agricultural output and aquaculture have declined significantly, as well as cultural legacies and loss and degradation of traditional agriculture and fishing techniques. These changes have resulted in psychological and social anguish, increasing crime rates due to economic insecurity, and greater vulnerability to climate-related calamities such as floods and storms. The ecological repercussions include aquatic species migration and death, water body pollution, and general ecological imbalance. Reduced fertile land drastically limits food production capability, resulting in increased food insecurity. Rising food prices disproportionately harm low-income households, worsening malnutrition and hunger, particularly among vulnerable populations. Uncertainty about the sustainability of agricultural investments serves to dissuade potential commercial producers. The study indicates that unregulated urbanization in these wetland areas is incompatible with the SDG goals of reducing poverty and hunger and fostering sustainable development. It advocates for the immediate implementation of sustainable urban design that balances development and environmental conservation. Key proposals include enforcing internationally recognized environmental legislation such as environmental impact assessments, biodiversity protection frameworks, and coastal zone management acts. To prevent the ongoing damage, the report underscores the importance of coordinated policymaking among government officials, environmental agencies, and local people. Such partnership should prioritize adherence to urban master plans and building rules, track carbon emissions, and support regenerative development initiatives. Finally, connecting development goals with ecological preservation is necessary to restore environmental integrity, assure food security, and promote sustainable livelihoods for current and future generations in the Epe and Ibeju-Lekki regions of Lagos, Nigeria, and other analogous cities.