This chapter identifies critical aspects related to lifestyle and behaviors throughout the lifespan that can best help to prevent and delay the onset of dementia. In the United States, dementia is projected to affect up to 13.8 million people by 2050, growing from an estimated 5.8 million today. The social and economic impact of dementia is significant, with women being diagnosed more often than men. While there are US Food and Drug Administration- approved medications for use in moderate- and late-stage dementia, none prevent, reverse, or cure the disease. Utilizing upstream lifestyle approaches offers the best opportunity to prevent or delay the onset of symptoms and can likely aid in the management of the disease. Additionally, therapeutic lifestyle approaches promote improved quality of life at all stages. This chapter will discuss the impact of therapeutic lifestyle approaches, such as improved nutrition, optimized sleep, and increased physical activity, in preventing dementia. Additionally, this chapter explores other important aspects of a healthy lifestyle, including management of stress, avoidance of addictive substances, and maintenance of healthy social relationships throughout the lifespan. Adopting these strategies as part of an overall healthy lifestyle is important to brain health and the prevention of dementia.