Editor's Note:  You've heard it before - it isn't safe to lose more than two pounds per week. The question is, why? And does this rule apply to everyone? Tom Venuto tackles this issue in this recent Q&A column.

Dear Tom,

I know you preach losing one to two pounds per week. Does this apply to everyone? I'm currently at a 31% body fat level. I was curious to know if it's ok to lose up to three pounds per week until I get to a 25%-20% body fat level. Will my body fight against such a loss? Thanks in advance for your time, knowledge, and response to this matter.

Sincerely,

Mac Diamond

It's usually best to aim for one or two pounds per week of weight loss. This is the recommendation of most nutrition and exercise organizations such as the American College of Sports Medicine and I'm in 100% agreement with this guideline. However, it's definitely ok to lose three pounds per week when you have a lot to lose. The more you have, the more you can safely lose per week because fat loss is relative to total body weight.

Generally the rule is that it's safe to lose up to 1% of your total body weight per week, so if you weigh 300 lbs to start, then 3 lbs a week is a reasonable goal. But there's a catch. What really matters is not how much weight is lost, but how much fat is lost. Where did the weight come from? Are we talking about fat weight or lean body mass?

For example, let's take a 260 pound man who has a lot of body fat to lose - let's call it 32%. With 32% fat, a 260 pounder has 83.2 pounds of body fat and 176.8 pounds of lean mass. Using this example, let's look at a few possible scenarios with weight losses ranging from two to four pounds per week.

Scenario 1: Suppose our 260 pound friend loses four full pounds instead of the recommended one to two pounds per week. Is this bad? Well, let's see: If he loses a half a percent of body fat, here are his body composition results: 256 lbs
31.5% body fat
80.6 lbs fat
175.4 lbs lean body mass
Out of the four pounds lost, 2.8 pounds were fat and 1.2 were lean mass. Not a disaster, but not good either. Thirty percent of the weight lost was lean tissue.

Scenario 2: If he loses a half a percent of body fat and only three pounds, here are his results: 257 lbs
31.5% body fat
80.9 lbs fat
176.1 lbs lean body mass These results are better. Although he lost less body weight than scenario one, in this instance, 2.3 pounds of fat and only 0.7 lbs of lean mass were lost.

Scenario 3: What if he only lost two pounds? Here are the results: 258 lbs
31.5% body fat
81.2 lbs fat
176.8 lbs lean body mass These results are perfect. Even though our subject has only lost two pounds, which seems slow, 100% of the two pound weight loss came from fat.

Scenario 4: Now let's suppose he loses three pounds and .8% body fat. 257 lbs
31.2% body fat
80.2 lbs fat
176.8 lbs lean body mass These are the best results of all. When the weekly fat loss is .8%, 100% of the three pounds lost is fat. So the answer to the question is yes - it's safe to lose more than two pounds per week... IF the weight is all fat or at least mostly fat with minimal lean mass losses.

One thing you should know is that water weight losses sometimes tend to distort these numbers, especially when you first begin a new nutrition and training program. The lean body mass number isn't just muscle. Lean mass reflects all fat free tissue, including water weight. That's why you shouldn't panic if you see small drops in lean body mass - some of it is water. When you lose large amounts of lean mass and/or if your lean mass drops consistently week after week, that's an indication that you're definitely losing muscle tissue.

The best advice I can give you is to focus on losing fat, not losing weight. If you lose three to five pounds per week, and it's all fat, no muscle - more power to you! Of course the only way to know this is with body composition testing. I recommend the Accu measure for home self testing as first choice. I suggest using the Tanita bio-electric impedance analysis scale only as second choice behind calipers for home self testing. Even better, get a professional caliper test from an experienced tester at a health club, or even a water (hydrostatic) or air (bod pod) displacement test.

Editor's Note:  The Accu measure Tom is referring to is the Accu-Measure body fat caliper. It is considered to be the most accurate body fat caliper for home testing. You can purchase the Accu-Measure 2000 Body Fat Caliper for less than $20 at BodyTrendsUSA.com. The Tanita bio-electric impedance analysis scale is simply a body fat scale. These scales look just like regular bathroom scales except they tell you your body fat percentage as well as your total weight. They are so much easier to use than a body fat caliper and in my opinion, give accurate enough results to highly recommend them. You can purchase Tanita body fat scales for under $60 at BodyTrendsUSA.com.

From literally hundreds of client case studies, I can confirm that it's VERY rare to lose more than 1.5 - 2.0 lbs of weight per week without losing some muscle along with it. If you lose muscle, you are damaging your metabolism and this will ultimately lead to a plateau and weight re-gain. Lack of patience is one of the biggest mistakes people make when it comes to losing weight. If you want your weight loss to be permanent, you have to take off the pounds slowly.

Read other articles by Tom Venuto

About the Author

Tom Venuto is an NSCA-certified personal trainer, lifetime natural bodybuilder, certified strength & conditioning specialist (CSCS), and author of the #1 best selling diet e-book, "Burn The Fat, Feed The Muscle." Tom has written hundreds of articles and has been featured in IRONMAN, Natural Bodybuilding, Muscular Development, Exercise for Men and Men's Exercise. To contact Tom or get information on his e-book, visit www.BurnTheFat.com