Recently, I was sitting on a tightly packed plane as it circled up to 19,000ft. It was making loads of noise, and I could see the people around me were scared. But I felt nothing. In 2005, I was diagnosed with Cushing’s syndrome, after years of misdiagnosis – doctors would often tell me I was just overweight. Cushing’s is a rare condition that affects one to two people in a million per year in the UK, and is caused by the body producing too much cortisol. Cortisol is a hormone that regulates a range of processes, including the stress response; if it’s not treated, it can be very serious. Symptoms can range from severe weight gain to high blood pressure. For the next six years, I had various operations. Three brain operations didn’t work. An adrenalectomy to remove the adrenal glands, which produce cortisol and sit above the kidneys, didn’t succeed either. (Cushing’s is often caused by tumours in the glands themselves or the brain). I was distraught. Eventually, in 2010, I was offered another operation, which would involve cutting the right side of my body open and permanently removing a rib so they could reach what was left of the adrenal gland above my kidney. I was told it was going to be very painful, but I was desperate. I wasn’t born without fear – I was actually a very fearful person. During those years of surgeries, I used to wake my wife up crying because I feared death. But after the last operation, I remember waking up in a hospital bed with tubes coming out of me. I had been on life support for five days. I was told there had been complications and I’d developed pneumonia and then meningitis. When I’d woken up from past operations, I’d cry out of panic. But, this time, I didn’t feel anything. The doctors explained that because my adrenal glands were removed, I could no longer feel an adrenaline rush. Most people who have this operation still get some semblance of the feeling but, because of my brain surgeries and other complications, the part of my brain that controls the feeling of fear has been turned off. News of my fearlessness spread after I was interviewed by my local radio station, and in 2016 a scientist who specialises in fear was brought in to test it out for a BBC science programme. I had to abseil down the 127-metre (418ft) National Lift Tower in Northampton while hooked up to heart monitors. The line on the monitor should have been going up and down rapidly, but it just flatlined. I felt no excitement, no suspense, no fear. Since then, I’ve been trying to test my fearlessness as I’m still hoping to get my sense of fear back. Everybody makes it out to be this amazing superpower – and it is, in a way – but there’s another side to it. I’m a husband and father of two children, and work as a broadcast producer and presenter. Before the last operation, I was always on edge watching my kids in the playground, but I don’t have that any more. Now my elder daughter is 17, and is going out with friends, and I have to think, what would a normal parent do at this stage? Would they be panicking? I have to keep thinking about how I should feel, when it should come naturally. We often associate adrenaline with fear, but it’s also linked to excitement, joy, nervousness. So other emotions have gone too. I remember the feeling when our daughters were born, the pure elation that filled my heart. I can’t feel it any more, and that is so hard. We’ve just booked a family holiday, and I’ve bought a new car – these are things that would once have brought so much excitement, but I’ve lost enthusiasm. It’s weird not to have anything to look forward to. Every day feels the same. I hope to raise awareness of Cushing’s and help others with the condition. Don’t get me wrong: I still feel love; I still feel that connection to my daughters and my wife. And I’m so grateful for their support and to see the joy and excitement they get out of life. I count myself lucky that I wasn’t born this way, and have got those memories to fall back on to remind myself how it used to be. I do the best I can, and hopefully my daughters know that. As told to Naomi Larsson Piñeda Do you have an experience to share? Email experience@theguardian.com