In an ideal world, everyone would take a long-term approach to dieting, trying to lose weight/fat gradually. They’d make small changes to their eating habits, activity patterns, or both. But we don’t live in an ideal world there are situations when that simply won’t work. Or where people simply aren’t willing to be patient.
Maybe they need to drop weight fast for a special event, or they are an athlete or bodybuilder who has to get in shape and is under a time crunch. Maybe they just want the diet over as quickly as possible. Whatever the case, sometimes you need a way to drop both weight and fat quickly to reach your goals. That’s where The Rapid Fat Loss Handbook: A Scientific Approach to Crash Dieting comes in.
An interview with Lyle McDonald, author of “The Rapid Fat Loss Handbook”
Wannabebig: How did you come up with the idea for this new diet?
Lyle M: Well, it’s really not a new diet by any stretch. I mentioned the Protein Sparing Modified Fast (PSMF) back in my first book on ketogenic diets and the idea has been floating around since the 70’s, when it was first developed. I think the major impetus to re-examine it (and make the changes I did) was looking at Di Pasquale’s “Radical Diet” (which is just a PSMF retooled version of the Anabolic Diet) and Dr. Serrano’s “Extreme Crash Diet”.
Both are essentially PSMF types of diets. So, I figured, why not jump on that bandwagon. Also I was a little disapointed that both of the other diets are so heavily supplement-based, when I think such a diet can readily be done around whole foods (I think this is also beneficial from the standpoint of re-teaching better eating habits).
Wannabebig: Who is the diet geared towards?
Lyle M: I made the book as general as possible, giving recommendations and specific changes based on initial body fat percentage and activity levels. Athletes involved in heavy training shouldn’t really use such a diet, since they won’t be able to sustain training intensity, but beyond that I tried to make it as general as possible.
Wannabebig: So, why not use a PMSF approach, what’s so unique about this method?
Lyle M: All I really did was modify a PSMF–this really isn’t anything new. The main changes I made were:
- Give different protein recommendations based on initial body fat and activity level (protein intake goes up as body fat comes down, and as activity goes up)
- Suggest that people use an essential fatty acid supplement
- I was very specific about how long different populations (again, based on body fat percentage) should stay on the diet (the leaner people are, the shorter their diet duration should be)
- I suggest the use of free meals (single meals that break the diet), refeeds (high-carb eating) and even full diet breaks (2 week periods off the diet) with the frequency, once again, depending on starting body fat.
Wannabebig: How much weight can someone expect to lose on average per week on this diet?
Lyle M: Total weight loss may reach 10-20 lbs of which a majority is water. True fat loss, depending on starting weight can be 4-7 pounds or so.
Wannabebig: Do you feel this is the healthiest approach to crash-dieting?
Lyle M: In that there is any healthy approach to crash dieting, yes.
Basically, when you crash diet, the goal is to minimize caloric intake while maximizing nutrient (and especially essential nutrient intake). This basically means you have to cut back to protein, essential fatty acids, vitamins and minerals (carbohdyrates being non-essential). As well, you want to at least limit lean body mass losses, which is another good reason to make sure protein intake is sufficient.
Wannabebig: What’s the most amount of weight you’ve seen someone lose with this method?
Lyle M: A few people have come in right at 20 lbs in 2 weeks. As above, that includes a lot of water weight. One person on my forum dropped nearly 35 lbs in 100 days, body fat dropped from 30% to 19% and the visible changes were major.
Wannabebig: How much of a concern should there be with muscle loss while on this diet?
Lyle M: To date, if anybody is having problems with muscle loss, nobody has mentioned it. The protein recommendations were set to ensure that LBM loss should be minimized if not eliminated.
Wannabebig: How much of a role does training and cardiovascular work play in this method (is ‘more,’ better)?
Lyle M: No, ‘more’ is certainly no better. Making exercise recommendations for the diet was a bit of problem. For people not already exercising, I really don’t think the crash diet is the right time to start. For folks already on a training program, volume and frequency needs to be cut way back, to maintenance levels. 2 short full body weight lifting workouts are more than sufficient to maintain muscle mass and strength. As far as cardio, it’s really not going to have a huge impact, except maybe to improve diet adherence.
Basically, when you’ve already got this monster caloric deficit, burning a few extra hundred calories with cardio just won’t accomplish much. One study even found that adding cardio to a PSMF increased the drop in metabolic rate (basically cancelling out the calorie burn of the cardio). And, in fact, most studies are finding that exercise probably plays its major role in weight mainteanance after the diet is over.
Wannabebig: Is there any room for cheating while using this method and still make progress?
Lyle M: Absolutely. Quite, in fact, one of the major modifications I made to the overall concept is recommending/requiring cheats. The first strategy is called a single free meal which is exactly what it sounds like, a single meal where you can eat more or less ‘freely’ and break the diet (I give some recommendations, mainly on what NOT to do, in the book). Next up is a structured refeed which is just a period of high carb overeating.
Finally is a full diet break, which is a period of 10-14 days where you go completely off the diet. This is mainly used by people doing repeated bouts on the PSMF to give them both a physical and mental break. All three strategies are also discussed in some detail in my other new book called “A Guide to Flexible Dieting.”
Wannabebig: Are there any major/minor differences between males and females that need to be addressed when using this method?
Lyle M: Not really. The biggest issue is that women, because of being lighter, typically have a lower metabolic rate. They shouldn’t expect as large a true fat loss because of it.
Wannabebig: How long can you stay on this program?
Lyle M: It actually depends on starting body fat percentage. The leaner that folks are, the less time they should spend on it. So individuals who are 15% body fat or lower shouldn’t use it for more than about 10-14 days tops. Fatter individuals may stay on it several weeks to a couple of months straight before needing a full diet break. There are a number of reasons that go into those recommendations one of which is metabolic slowdown.
Leaner folks tend to have larger problems with metabolism crashing; there is also the issue that leaner folks are typically more active and staying on such a diet for too long will end up cratering training performance. The fatter people are, or the less active, the longer they can be on the diet. As well, empirically, fatter people don’t seem to have as many problems with hunger and such staying on the PSMF for extended periods.
Wannabebig: What would you say is the most difficult part of this program dieters will face?
Lyle M: Probably hunger and the relatively small amount of food. Then again, a lot of people find that hunger goes away probably for the same reasons it occurs on a ketogenic diet. As well, if you’re eating mainly whole proteins and the amount of vegetables I recommend, the amount of food you get to eat is decent. Some people also feel low-energy, just like on ketogenic diets.
Wannabebig: Are there any supplements you recommend while using your program?
Lyle M: Perhaps the most important is the EC stack, and I devote an entire chapter to discussing the issue of metabolic slowdown and why the EC stack is so damn important. A basic multi vitamin/mineral is a good idea and additional intakes of calcium, sodium, magnesium and potassium won’t hurt. I guess if you count fish oils as a supplement, those need to be consumed. Beyond that, very little is required and you can do the entire diet with whole food: lean protein sources and lots of vegetables.
Wannabebig: Thanks Lyle.
Written by Maki Riddington
Discuss, comment or ask a question
If you have a comment, question or would like to discuss anything raised in this article, please do so in the following discussion thread on the Wannabebig Forums – How To Lose 10 Pounds in 1 Week – A Scientific Approach to Crash Dieting discussion thread.