I was looking back at some of John's food logs from the early days, and while we all know that, in retrospect, it probably wasn't the best idea for him to maintain a 1000+ calorie a day deficit for such an extended period of time (I believe it was 3-4 months where he was averaging around 1300-1500 calories a day).

BUT... I'm wondering how long of a period IS reasonable for an individual to go on a severely restricted plan like that (provided all the nutrient values are within the generally accepted guidelines) before significant issues (muscle loss, fatigue, etc.) set in. I'm NOT talking about trying to build mass or gain strength during this period, but simply to maintain the current activity levels without incurring major setbacks.

For example, the BMR for a 175lb male is 1750. Multiply that number by an additional 40% to allow for typical daily activities and you come out around 2500 calories. Add in 500 calories in exercise (30 minutes weight training plus 20 minutes cardio per day) and you are around 3000 calories per day to maintain the current weight.

On the Jeremy Likness site, it suggests that 8x body weight is the lowest one should go for "extreme" fat loss. At 175lbs, that's 1400 calories, or a 1600 calorie a day deficit. Given the above calculations, that would translate to three pounds per week. A little higher than what would typically be recommended, but still reasonable provided those 1400 calories are all nutrient-dense and within the proper ratios.

But to get back to the question at hand... how long would be too long to try and maintain this level of intake? A week? Two weeks? Four weeks? Twelve weeks? I realize there is no "right" answer, but I'm interested in finding out what the collective thinks.

Three days would be too much for me.

It depends a great deal how your food intake and mood are related. I tend to agree with everything wite_owl (http://forums.johnstonefitness.com/showpost.php?p=351089&postcount=10) posted last night.

If I tried a program that wasn't healthy, my mood and energy levels would be launched into severe rebellion mode. I'm starting to wonder if maybe I'm one of the few who have that protective mechanism.

If you're exercising regularly, I think 10 x your body weight in calories is the lowest you should go for any duration of time greater than a couple of weeks. How much of a calorie deficit does the 8x body weight PLUS your cardio put you at?

It also depends how far you are away from your goal weight. I think cutting plans are more successful in the long term when they are stretched out to 12 weeks or more, so if you have less than 36 pounds to lose, aiming to lose 3 pounds per week just spells big trouble.

How much of a calorie deficit does the 8x body weight PLUS your cardio put you at?

Good catch... I have to ASSUME that the calculator on the Likness site uses the BMR+40% factor to compute caloric intake, but does not include additional exercise. 1400 calories - 500 calories in exercise per day would yield 900 calories. WAY too low...

I completely agree with the correlation between mood and intake, and realize that it differs from person to person. But taking that out of the equation, I'm more interested in the physiological aspects of extended caloric restrictions, and at what point the damage done exceeds the benefit of the resulting weight loss.

This reminds me of a conversation i was having with a friend discussing caloric needs for the da ....he was asking how many calories i take in...and i said around 27-2900...he was like damn thats a ton...i have to take in 1500 to lose weight...this guy is 6 feet tall and weighs 270 easy......no wonder he has never stuck with any type of nutrition program

I don't think there's a known answer as to how long before you start to do damage. What IS known is that the body remembers the extreme famine conditions and becomes metabolically fragile. It takes a long, long while to straighten out your metabolism if you've done an extreme prolonged deficit.

Here's an example for you (example given is a famous 6 month study in starvation):

The Athlete's Kitchen ~ Copyright: Nancy Clark, MS, RD 2/00

"My body must have a metabolic defect-I'm always hungry."
"I don't know if I need to see a nutritionist or a psychologist. I often devour a box of crackers in the blink of an eye. I feel like I'm binge-eating...and that scares me."
"I try not to keep cookies in the house, because when they're there, I eat them--too many of them."

For many active people, food is a feared enemy. Runners, skaters, and rowers alike try to stay away from it. They endure hunger all day. When they do succomb to food, their eating tends to be a fast and furious frenzy that's seemingly out-of-control. Some of these clients have a full-blown eating disorder, but the majority are simply hungry. Too hungry.
Being hungry all the time is not a personality quirk. Rather, hunger is the body's request for fuel. Hunger is a very powerful physiological force that creates a strong desire to eat. Unfortuantely, in our thin-is-in society, many active people fail to honor this simple request because they fear food as being fattening. The thought of eating elicits a sense of panic: "Oh no, if I eat, I'll get fat."
Not the case. Most athletes eat without getting fat! Food, after all, is fuel. But problems do arise when food is denied and deprived (as happens with a strict reducing diet), when hunger becomes the norm. The result is an abnormal physiological state that is known as starvation.
Starvation has been inflicted upon many people, including third world natives suffering from famines, poverty-stricken people at the end of the month when no food money is left, and victims of the World War II concentration camps. Starvation is also common among athletes who are intent on losing weight. These include wrestlers, light-weight rowers, jockeys and others who participate in sports with weight limits, as well as the athletes who simply believe thinner is better and diet themselves to (supposed) perfection.
The question arises: What's the cost of starvation? What happens to the body and the mind when food is restricted and body weight is abnormally low? In 1950, Ancel Keys and his colleagues at the University of Minnesota studied the physiology of starvation. They carefully monitored 36 young, healthy, psychologically normal men who for 6 months were allowed to eat only half their normal intake (similar to a strict reducing diet or anorectic eating). For 3 months prior to this semi-starvation diet, the researchers carefully studied each man's behaviors, personality, and eating patterns. The men were then observed for three to nine months of refeeding.
As their body weight fell to 25% below baseline, the researchers learned that many of the symptoms that might have been thought to be specific to anorexia or bulimia were actually the result of starvation. The most striking change was a dramatic increase with food preoccupation. The subjects, similar to people with anorexia, thought about food all the time. They talked about it, read about it, dreamed about it, and even collected recipes. They dramatically increased their consumption of coffee and tea, and chewed gum excessively. They became depressed, had severe mood swings, experienced irritability, anger and anxiety. They became withdrawn, had little sexual interest, and lost their sense of humor. They had cold hands and feet, felt weak and dizzy, and their hair fell out. Their basal metabolic rate (the amount of food needed to exist) dropped by 40% as the body adapted to conserve energy. (Do these changes sound familiar to anyone you know?)
During the study, some of the men were unable to maintain control over food; they would binge eat if the opportunity presented itself. During the refeeding period, many of the men ate continuously--big meals followed by snacking. Several ate until they were uncomfortably full, became nauseous, and then vomited. These abnormal eating behaviors lasted for about 5 months; by 8 months, most of them regained their standard eating behaviors. On average, they initially regained 10% more than their original weight, but then gradually lost that excess and returned close to their baseline weight.

So what can we learn from this starvation study?
1. Preoccupation with food is a sign your body is too hungry. Hunger creates a very strong physiological drive to eat.
2. Binge eating stems from starvation. If you worry about being unable to stop eating once you start, you have likely gotten too hungry.
3. Weight is more than a matter of will power. That is, if you lose weight, your body will fight to return to a genetically normal level.
4. Dieters who restrict to the point of semi-starvation are likely to regain the weight they lost--plus more. Hence, if you want to permanently lose weight, you simply need to push yourself away from the dinner table when you are content but not stuffed, when you can say to yourself, "I've had enough to eat. I could have more but I'd rather not because I'd rather be a little leaner."

You might find it helpful to know how many calories you are supposed to eat to maintain or to lose weight. To do this, simply--
· Take your weight and multiply it by 10. This gives your resting metabolic rate (RMR, the amount of energy you need to simply exist, pump blood, breathe, etc.). If you weigh 140 pounds, your RMR is about 1,400 calories--the amount you'd burn if you were to run for 14 miles!
· Add to your RMR about half that number for activities of daily living. For example, if you weigh 140 lbs. and are moderately active (without your purposeful exercise) you need about 700 calories to come and go.
· Next, add calories for purposeful exercise. For example, a 140 pound person would need about 1,400 calories (RMR) + 700 (daily activity) + 300 (for 30 minutes of aerobic activity) = 2,400 calories to maintain weight. To lose weight, deduct 20%--to about 1,900. This translates into 600 calories for breakfast/snack, 700 for lunch/snack, and 600 for dinner/snack--and that's the reducing diet!
The next time you get into an eating frenzy and wonder if you are borderline bulimic, calculate your day's intake. You'll likely see a huge discrepancy between what you have eaten and what your body deserves. Recognize hunger's power--and stop getting too hungry!

Nancy Clark, MS, RD is nutrition counselor at Boston-area's SportsMedicine Brookline and author of Nancy Clark's Sports Nutrition Guidebook, 2nd Edition. To order this best-selling book, send $20 to Sports Nutrition Materials, 830 Boylston, St #205, Brookline MA 02467 or visit www.nancyclarkrd.com.

Excellent article Gordo... thanks for posting that. I will be saving that to refer to some of my clients in the future, as well as sending it to a few JSFers.

Yeah I like that one....puts it in real world terms.

Good catch... I have to ASSUME that the calculator on the Likness site uses the BMR+40% factor to compute caloric intake, but does not include additional exercise.I wouldn't be too sure about that. Lightly active is a 1.375 multiplier, or BMR+37.5% to use your terminology. Lightly active means light exercise/sports 1-3 days a week. So I think BMR+40% does include exercise, but maybe not as much some people do.

In my recent cut I lifted two days a week (TBT), did cardio four days a week, and was pretty much inactive otherwise, and calculated my activity factor as 1.384 based on my fat loss over several weeks. So I was burning slightly less calories than the Likness BMR+40% according to my calculations.

Have you ever tried to eat at 8x bodyweight while doing heavy exercise?

You won't be able to. I think I could do it for one day. Well, actually, I could probably do it for 2 or 3 days, but after the first day I'd feel myself deteriorating/getting sick/extremely hungry.

I agree with Andrew.

I also agree with Berardi's comments about upping your activity level before you tinker with your calories. I have a general rule not to drop below 2,000 calories unless I'm desperate..

Have you ever tried to eat at 8x bodyweight while doing heavy exercise?

You won't be able to. I think I could do it for one day.

Well I did it more or less by accident and mistake over yesterday and today. It wasn't that bad, but I do a lot of endurance work which really takes the edge off going a bit long between meals. But I'm on the way home now to go eat.

Good catch... I have to ASSUME that the calculator on the Likness site uses the BMR+40% factor to compute caloric intake, but does not include additional exercise. 1400 calories - 500 calories in exercise per day would yield 900 calories. WAY too low...

Yeah that is sort of what tripped me up. I forgot that I started adding 1000 calories of extra cardio on what used to be the rest days. Duh.