Nutritional status and dietary intake play a significant role in the prognosis of breast cancer patients and may modify the progression of disease, as well as influence risk for comorbid conditions, such as osteoporosis and cardiovascular disease. A critical review of relevant clinical and epidemiological studies identified through MEDLINE and CINAHL searches was undertaken to provide the clinician with a summary of evidence that could form the appropriate guidance of women diagnosed with breast cancer who seek to reduce their risk of progressive or recurrent disease, and improve their overall health. Currently, healthy weight control with an emphasis on exercise to preserve or increase both lean body and bone masses, and plant-based diets that include ample amounts of nutrient-dense, low-energy density foods, particularly vegetables, can be recommended. Furthermore, diets high in vegetables, fruit, whole grains, and low-fat dairy foods, and low in saturated fat, may help to lower overall disease risk in this population.