Just recently I have started to have difficulty eating during and after my morning rides. I always eat breakfast before my morning rides and try to ensure I eat enough during my ride. I have been forcing me to have something to eat, like a fruit smoothie or pasta. I've been riding for about 2.5 years and have recently increased the number of kms I'm riding. When you do a lot of physical activity and your nervous system becomes aroused your body actually shuts down the metabolic system, so we have trouble digesting food. I think this is what has caused me to have trouble eating. Maybe this is what has happened for you.