When I first started working in London for a company which openly celebrated slenderness (a recognised and disturbing theme in many organisations), I found myself skipping lunch most days and dining on a small bar of Galaxy chocolate and a packet of crisps whilst walking down Tottenham Court Road on the way to meet friends in the pub. I was short of money and trying to lose weight. The pressures of work and socialising didn’t leave me with time to exercise with any intensity, so deprivation it would have to be. 

It’s not that I was ignorant about nutrition or didn’t know how to cook. I grew up in a home filled with the most wonderfully nutritious, homemade food. I owned many recipe books, and knew how to eat a balanced diet, at least in theory. But cooking just for myself, having what felt like very limited time, and wanting to spend any spare pennies on beautiful clothes instead of sensible food sent any sensible theories flying out of the window.

My ‘diet’ worked, but I felt dreadful. My heart raced on the bus, I couldn’t remember things I needed to remember and I suffered terrible headaches. For all the looseness of my clothes, the approach was glaringly unsustainable.

Soon requiring myself to think straight from morning through to six or even seven pm as I grew more ambitious in my role, I developed a new approach to food and exercise, which avoided sugar highs, post-caffeine jitters, accommodated the constraints of working life and to this day keeps me fitting into the same clothes I splurged my meagre salary on back then. The lure of quick fix fad diets, periods of intense travel for work, a couple of half marathons and a twin pregnancy have meant I’ve sometimes strayed off the path – but mostly I’m still doing the same thing.

The good news is that, unlike so many others, my approach requires no special equipment, no excessive commitment to punishing workouts and no more money than you’d earn on a bus-fare budget (the tube being an unaffordable luxury in those early London days). It is also utterly sustainable and suitably tasty. So now Christmas is officially over, it is time to ditch your green smoothie, caveman or dukan diet before you’d give it up anyway in mid-January. This is a way to see you through each working day and, indeed, the whole year through. I’ll save my ideas on exercise for another time.

For a perfectly balanced and energy-filled day in the office …

1. Leave a glass of water in the kitchen the night before. Drink this first thing in the morning. Then shuffle over to the kettle and brew yourself a cup of weak green tea – anything stronger will leave you feeling jumpy. Breakfast can wait until you reach the office (unless you have a very long journey or an early morning meeting – in which case you might eat a handful of raw almonds and a banana before setting off.)

2. On arrival at your desk, breakfast richly. It’s a wonderful accompaniment to reading emails and planning the day. A third of a pot of Greek yoghurt (150g) with some sugar-and-wheat-free muesli, topped with a good handful of blueberries or half a banana, and sunflower seeds. Unsweetened buckwheat flakes and puffed quinoa with organic milk (you may prefer non-diary alternatives such as soya or almond milk – I do) with a scattering of nuts on top are another ideal combination.

3. Sometime late-morning (around 11am), when things are starting to drag but lunch still seems a long way off, a decaf coffee (not too milky) can lift your spirits. If you’re peckish and you know you won’t have time for lunch until 2pm,, eat a few almonds or walnuts and an apple.

4. Force yourself out of the office at lunchtime, whatever the weather and your workload. Nothing will make you more unproductive than sitting all day. A brisk walk of at least 15 minutes will relieve stress, justify your appetite, and clear your head. Ideally, you’d eat on a step in the sunshine, but if deadlines and office politics don’t permit, good food at your desk will do. The key is balance – a decent amount of protein, some veg and a smattering of carbohydrate. Leave off the bread – it will only weigh you down for the afternoon. Of course, it’s better to bring your own food from home (here’s a simple idea for the perfect lunch), but there will be plenty of times when you don’t. If M&S is your only option, choose a big green salad, and throw in some smoked fish and a rice or lentil salad too. Perhaps a pot of hummus on the side. In cafes, go for soup plus a protein-rich salad. Dessert can wait for later.

5. At 4pm, when the hours until home time stretch endlessly ahead of you, dessert is a tremendous reward. Make a cup of herbal tea, and slice up an apple. Eat it slowly, then top it off with a few dried apricots and single, delicious piece of dark chocolate (don’t even consider anything less than 70% cocoa content).

6. Sipping a bottle of water on your journey home (sparkling or still) will subdue those hunger pangs, which usually send you hunting down Whisper Mints in Sainsbury’s before getting to your front door. If you can bear it, get off a stop early and walk the last bit of the way home.

7. Dinner need be no more than a few bits of raw veg (carrots, celery, cucumber, half an avocado), a couple of rye bread crackers and a little hummus or cream cheese – perhaps a boiled egg too. If you didn’t have yoghurt for breakfast, a small bowl with a few seeds and raisins makes for a delicious end to your meal. One more cup of herbal tea before bed, and you’re done.

The recipe for the perfect packed lunch is here …

Ingredients

• 50g quinoa or brown rice
• Handful of roasted nuts (hazelnuts, walnuts and almonds are all good)
• 1/2 avocado
• 1/4 cucumber
• 1 grated carrot
• 1 fillet of smoked mackerel / salmon / tuna / feta / goat’s cheese
• Lemon juice / cider vinegar / olive oil

Method

At the beginning of each week, make a big batch of quinoa or rice. Make sure to put rice in the fridge immediately after cooking it (otherwise it can turn toxic). Roasting nuts is easy. Scatter some on a baking tray and leave in the oven at 200C for about 20 minutes (maximum).

The night before, scoop a couple of big tablespoons of rice or quinoa into a plastic pot each evening. Throw in the handful of the nuts, add some chopped cucumber, and the grated carrot. Salt (in absolute moderation) and pepper (in abundance) to your taste.

In the office keep a supply of nearly ripe avocados, smoked fish or tuna, a lemon, a bottle of olive oil and some cider vinegar. Add the avocado and fish (or cheese if you’d prefer) just before you want to eat the salad. Finish with a generous squeeze of lemon juice or drizzle of vinegar, depending on your preference, and a good dash of olive oil. Half avocados keep well in the fridge, when stone-side down in a standard mug.

Other ingredients which you might consider adding, in any combination, the evening before include:

• Well-rinsed tinned chickpeas (1/3 of a tin will do)
• Tomatoes
• Peas, green beans, broad beans (cooked from frozen)
• Beetroot (easy to boil whole and then peel and cube / or buy pre-cooked)
• Broccoli
• Chopped parsley (kitchen scissors do a brilliant job)
• Raw celery
• Olives
• Roasted sweet potato
• Raisins