I have spent the past few weeks reviewing an iPhone app called Lose It!, by Fit Now.  This app is free, and works on the iPhone, iPod touch and iPad.  Essentially it is a sophisticated journal for tracking food, exercise and weight, with simple included weight loss programs.

I was very impressed with this app as a weight loss tool.  It is very high quality and the price can’t be beaten.  To start you enter your current weight, target weight, and desired rate of weight loss.  The app then estimates your resting metabolic rate, and calculates a daily calorie budget.  From then it is up to you to enter everything you eat and every exercise you do, the app tells you how many calories you have left each day and how you are progressing.  It also syncs to personalised on-line service where you can view detailed reports, and even download data to a spreadsheet.

Potential downsides include the time taken to enter data, the food database, and the method for estimating resting metabolic rate.  Like any food journaling, this app requires you to diligently enter every food eaten, and every exercise performed.  This is a bit of a chore at first, but soon takes only 1-2 minutes per meal, particularly if you are married to you iPhone like I am.  The food database is strong on pre-packaged foods and chain restaurants, but it takes a little for time if you cook from scratch, and can be difficult at independent restaurants and stores.  It is possible to enter data of nutrition labels to add new foods to the database.

Lose It! calculates your resting metabolic rate using the Mifflin equation, and assumes a sedentary job.  The calorie budget is calculated assuming a 3500 calorie deficit is required to lose one pound.  These estimates are fairly accurate for most people, but not everyone.  In particular you can alter your calorie budget if you have had your resting metabolic rate measured by calorimetry.

Overall I can highly recommend this app.  It makes food and activity journaling very straightforward for iPhone users.  You can track protein intake if you wish, sync with an on-line service, and share goals with friends.  Also my predicted weight loss was accurate when trialling this app.  I would recommend this app for people before and after weight loss surgery who want to know how many calories they are eating, and burning, and who want a little extra help getting their weight loss on track.