A study in 633 patients who survived breast cancer showed that higher intake of ω-3 polyunsaturated fatty acids (PUFAs) reduces inflammation and fatigue. The participants completed a questionnaire about food frequency and dietary supplement, and provided a blood sample to assess C-reactive protein (CRP) levels and completed a fatigue and vitality test 30 and 39 months after diagnosis, respectively. Those with higher intake of ω-6 PUFAs had greater CRP levels and risk of fatigue than those with higher intake of ω-3 PUFAs.