It could be to do with what you�re eating. All food contains sugar and certain foods release their sugar quicker than others. Carbohydrates (potatoes, pasta, rice etc), anything made from white flour and anything containing added sugars (cakes, chocolate, ready meals and practically everything else these days unfortunately!) all release sugars quickly, which leads to you feeling tired soon after you�ve eaten. Proteins (fish, meat, nuts, seeds) and fibre (wholegrain / whole meal breads, oats fruit & veg) release their sugars much slower, and keep your energy levels up for longer. Sounds confusing, but if you google �blood sugar levels� you should find lots of info!