A.Yes, there are a few.
We have heard some reports of it lowering high blood pressure. In one instance we know of, blood pressure actually went from high to low (which also isn’t good for you). We recommend that if you have high blood pressure you consult with your doctor and introduce the product into your diet very gradually while monitoring your blood pressure under doctor’s supervision. This is especially important if you are on medication to lower your blood pressure. Astaxanthin may bring blood pressure down to desired levels while continued use of medication may push blood pressure further down.
As with every supplement, you should consult your doctor if you are pregnant or battling serious disease or cancer. There are no studies that we are aware of relating to astaxanthin and pregnancy or breast-feeding.
Regarding cancer, we have spent a lot of time and effort reading the scientific literature. We found that some antioxidants have pathways that may strengthen all cells, including cancer cells, however we are not aware of any studies that show that astaxanthin may accelerate cancer spread. We clearly do not make any claims regarding astaxanthin and cancer and recommend the patient consult with their physician.