How much protein should I be eating?

Base your protein intake on your lean body weight.

This is the best advice I've read (so far) about how to calculate daily protein requirements to preserve muscle while reducing body fat. +DailyProteinRequirements +PreserveMuscle +ReduceBodyFat

It comes from Christian Finn.  You should read the whole muscle preserving article on Muscle EVO, but I summed it up below:  +ChristianFinn +MuscleEVO

Your weapon of mass preservation

Most protein recommendations are given in percentages 30% protein, 40% carbohydrate, 30% fat.

The problem with using percentages is the numbers are affected by your total calorie intake.

30% protein on a 1500 calorie diet is very different than 30% protein on a 2500 calorie diet - 113g vs. 188g.

There is a better way.

If you're concerned about preserving muscle mass while lowering body fat percentage, base your protein intake on your weight.

One gram of protein per pound of bodyweight.  A 180 pound person would consume 180g of protein.

Protein intake stays the same no matter how many calories you're consuming.

There's an EVEN BETTER way.

For people who are over weight, there's a problem with basing protein intake on body weight.  A 300 pound man should NOT be eating 300g of protein. 

A better way is to base your protein intake on your lean body weight.  A 190 pound man with 15% body fat would eat 162g of protein.  A 190 pound man with 25% body fat would consume 143g.

Base your protein intake on your LEAN body weight.

The closer you are to your genetic limit in terms of muscle growth, the slower the gains will come.

And the slower your rate of growth, the less protein you need to support that growth.

In short, if you want to hold on to the muscle you currently have while you drop fat, 1 gram of protein per pound of lean body mass will be enough for most people, most of the time.

You can eat more if you like.

But it's not going to make a great deal of difference to your results.

How do you calculate body fat percentage?

The easiest, most consistent, and most cost-effective way to estimate body fat percentage is to use pictures.  Less expensive than water tanks, more consistent than calipers. +BodyFatPercentage

Marc Perry has body fat percentage picture examples and descriptions on his blog BuiltLean. +MarcPerry +BuiltLean

If you aren't subscribing to these two blogs, - Muscle EVO and BuiltLean - check 'em out.  These blogs are well-written and have a lot of useful info.