Park YMM, et al. - Researchers assessed the association of diet-dependent acid load with breast cancer via analyzing data from 43,570 Sister Study participants who completed a validated food frequency questionnaire at enrollment (2003–2009) and met eligibility criteria. They used the Potential Renal Acid Load (PRAL) score to estimate the diet-dependent acid load. At least 1 year after enrollment, invasive breast cancers were diagnosed among 1,614 participants. Increased risk of breast cancer was evident in correlation with the highest PRAL quartile, indicting greater acid-forming potential. Given the positive correlation of PRAL scores with meat consumption and negative correlation with fruit and vegetable consumption, results indicated a protective effect of diets high in fruits and vegetables and low in meat against hormone receptor-negative breast cancer.