I have to give some credibility to this. I started drinking Premier Protein shakes because I am on a food plan to lose weight and others have recommended these shakes as a meal or snack. I was drinking 1-2 per day. I have had palpitations in the past and know I am predisposed to them but since starting the food plan and drinking the shakes I have been having debilitating palpitations and extreme shortness of breath. I read about the connection on this forum and since my doctors have not been able to find a reason for my increased palpitations I decided to look closely at the ingredients in Premier Protein and sure enough, it contains whey. So I stopped drinking the shakes and felt a lot better - still some palpitations but nothing like I was going through since starting them. And I never had shortness of breath like I had with the palpitations either. I switched to Muscle Milk that does not contain whey and felt far fewer palpitations. Today, I was in a rush and grabbed one from the fridge. I though I had removed all the Premier brand and didn't even look at it - just drank it. About 10 min. later I was having terrible nonstop palpitations and severe shortness of breath. After about three hours symptoms lessened and then stopped completely. Tonight I noticed that there were some Premier shakes in the fridge that my husband had put there not realizing my issues with them. I strongly feel there is a connection and that I have a whey allergy. So you are not alone. Whey is in many processed foods and from now on I am going to scrutinize every label before I eat anything at all. My sister has a daughter with severe food allergies who is an adult now and outgrown most of them but my sister became an ingredient detective and found whey in products like some brands of tuna fish. Smaller amounts are not on labels so she had called every manufacturer before letting her daughter eat any processed food. I am hoping that this is the answer to my situation because my doctors are stumped. I hope you find a solution.