Nutritional factors that contribute to maintaining energy levels include adequate hydration, balanced macronutrient intake, and consuming whole, nutrient-dense foods. Complex carbohydrates like whole grains and fruits provide lasting energy, while healthy fats and proteins sustain energy levels throughout the day. Additionally, incorporating micronutrients, such as vitamins and minerals from diverse food sources, supports metabolic functions and prevents fatigue. Regular meal timing and portion control also play a significant role in avoiding energy crashes and ensuring steady energy throughout daily activities.