I have the same fear. The last few lbs are the hardest to shift but i went for a 5.4km run earlier and have been reading lots of books about nutrition and find i'm not putting in enough food to fuel my daily activities let alone the exercise on top. I've watched a lot of the Biggest Loser programs and it's interesting to watch the contestants. Some weeks stress plays a part and prevents weight loss, others, not enough food to fuel the body means they stay the same or even gain. I've been guilty of eating lots of vegetables and salads but not adding in healthy fats like avocado, olive oil and then pulses, lentils, nuts and seeds. I'm addressing that now and already finding a difference. The creamy broccoli soup tastes amazing and has a good mix of the right nutrients.

Everyone's different so it's hard to advise on numbers but i think for me i need to eat a minimum of 1400 calories a day and add on extra calories equivalent to those burnt during exercise. I'm giving that a try whilst on this cleanse and for the 2 weeks after to see what happens.

Good luck with finding your magic calorie number.