Long chain omega-3 polyunsaturated fatty acids are a necessary part of our diet.  They have an anti-inflammatory effect and can decrease cardiovascular disease, improve circulation and blood pressure, improve memory and cognition, and benefit the nails, hair, and skin. Omega 3 fatty acids can also help enhance one’s quality of life and functional health status while going through cancer treatment.  
 
It is important to note that EPA and DHA are natural blood thinners.  If you're taking a blood thinner, please talk to your doctor before purchasing this product.  Also, due to its antioxidant effects, this product should be avoided 1 week before, during, and for 4 weeks after radiation.
 
References:
Omega-3 Fatty Acids for Breast Cancer Prevention and Survivorship
 
Protective Effects of Omega-3 Fatty Acids in Cancer-Related Complications
 
Oral Nutritional Supplements Containing N-3 Polyunsaturated Fatty Acids Affect Quality of Life and Functional Status in Lung Cancer Patients During Multimodality Treatment: an RCT