One of my friends once said that he spends £500 a month in Pret and I can see how if you go a few times a day its pretty pricey in there. Although I work in the City as a lawyer I'm not prepared to spend all my hard earned pennies on fast food. Instead I recommend:
1. Start the day with a hearty breakfast - if your days are anything like mine then it could be 3/4pm before I get my lunch so I always make sure I have breakfast. If you follow me on instagram you'll know that I love eggs. Two boiled eggs in the morning are a perfect slow release food to fuel the day. You can make your own the night before, or in a morning. I leave mine on the hob whilst I jump in the shower and then pop them out the pan, crack some salt over them and wrap them in foil. I shell them at work and the bit of salt works perfectly. My commute is a little over an hour and they're usually still warm too. Alternatively, Pret do ready shelled eggs with spinach for £1.60. Or try Rye bread with toppings, like nut butter or avocado. I'm lucky that there's a toaster at work but Rye bread tastes nice even if you don't toast it. Take a jar of nut butter for the topping as it tastes great, lasts a long time out of the fridge and fills you up. Alternatively, try mashing a banana on top. Rye bread is a perfect addition to your work drawer/food cupboard/hot box as it lasts a long time so you don't have to have the same thing every day and can double up as lunch if you get stuck. Or try yoghurt and fruit, top with oats and nut butter.
2. Get prepared: I fuel my day with three meals and two snacks; one at 11am and one at 4pm. If I don't have my own snacks I reach for cakes and biscuits (I swear it is someone's birthday every single day where I work) In most big cities you can pop into a small supermarket and grab a snack but it's much pricier. If you're buying things like yoghurts they're much cheaper in large superstore supermarkets for the same product. Grab a large bag of nuts and then portion them out at home, Don't do what I do and buy a large bag and take it in "for the week" and realise that by 11am on Monday morning you've eaten your way through a bag of cashew nuts at your desk which is clearly marked as "serves 4". My 4pm snack is usually a Fage yoghurt which fuels my afternoons and stops that horrid feeling when you get in from work of eating everything in your fridge.
3. Make healthy choices: let's face it, wherever you work there will be times where even with the best will in the world you will not be prepared. You might be out of the office at meetings and need to grab something on the go or leave your carefully prepared Tupperware on the kitchen table(please tell me I'm not the only one). When I need to grab something on the go an I usually turn this meal into a treat, no not a pasty, but something that tastes yummy. If I'm going to have to buy a salad I'm not going to opt for a few leaves and a cherry tomato. I want something I would never make myself. I want grains and I want loads of different veggies and often a bit of feta and beetroot. I normally head for M&S they do little pots of yummy food and you can usually get 2 for £3 which works well for another lunch for the following day. I also pick up some protein too so a packet of chicken, salmon or prawns. They do great little packs of these. My advice here would be eat to fill yourself up on good quality food. Don't go for a small quick sandwich option, go for a big meal to fuel your day. Let's be realistic, when it comes to performance reviews or plans for promotions at work no-one is going to think oh let's give it to the girl with abs they're going to look for someone who is full of energy and can put the hours in because they've fuelled themselves right. To me eating well isn't about aesthetics its about performance in and out of sport.
I've had a lot of requests for snack ideas and what I eat in a day so I really hope this has helped to show you some ideas.