I’m continually amazed at the number of women I speak with who have done the hCG diet at one point during their weight-loss journey.
I guess I shouldn’t be. I mean, it’s advertised vigorously, Dr. Oz has promoted it (don’t get me started on that guy), and it promises something plenty of people want: fast, easy weight loss.
But although I’m singling out hCG at the moment, everything I say from this point on applies equally to any “very low calorie diet”—in other words, any food plan that provides 800 calories or less per day. If your doctor has put you on a VLC diet and you’re under her supervision, go with my blessing.
For everyone else, my advice is to avoid hCG (and its close kin) like the plague!
Here’s just one way the hCG diet (and others) can hurt you:
Stick to hCG or any VLC diet for long, and you’re very likely to see a significant slowdown in your metabolic rate—that is, the number of calories you need every day.
Now, there’s nothing magical about the 800-calorie number. You could eat more than that and still suffer harmful effects if the percentage of caloric restriction is too great.
Let me explain how this works by telling you about a fascinating study published in 2012 that involved contestants on the U.S. version of the TV show The Biggest Loser.
One of the study’s authors was Robert Huizenga, the physician for the show. If you’ve seen The Biggest Loser, you know it’s a competition to lose massive amounts of weight as quickly as possible. The participants eat only about 1,000 calories a day, and they exercise for six to eight hours a day.
It’s the percentage of caloric restriction that counts
A 250-pound woman who does that much exercise would actually need an estimated 3,600 calories per day or more to maintain her weight. But if she’s only consuming about 1,000 calories a day, she’s taking a caloric reduction of more than 72 percent.
Let’s compare that to the energy needs of a 35-year-old 200-pound sedentary woman who is taking in 800 calories a day on the hCG diet. Her actual calorie need is about 2,000. If she consumes 800 calories every day instead, she’s reducing calories by 60 percent.
It’s an outrageous percentage—and one that’s going to cause all kinds of trouble.
The greater the percentage of calories you cut, the more you endanger your metabolism—and that’s one of the reasons it’s so vitally important to follow a safe, sensible program.
So how did this play out in Dr. Huizenga’s study? The researchers found that the dieters’ metabolic rate declined—but not just by the amount that should be expected, given that they were becoming smaller people and also losing some muscle mass.
Well, after six weeks, the daily resting metabolism of participants in the study had gone down on average about 244 calories; after 30 weeks, their metabolic rate had decreased by an average of 500 calories a day.
This is resting metabolic rate we’re talking about—so it has nothing to do with the amount of calories burned through exercise. It’s just the amount of calories their bodies need to sustain life.
Would you want to be ‘on a diet’ for the rest of your life?
Will this metabolic reduction eventually correct itself? The researchers don’t have the answer to that question.
If it does not—or until it does—those people will have to eat fewer calories than they “deserve” in order to avoid regaining the weight.
Can you imagine being on a seriously calorie-restricted diet for the rest of your life?
If I could boil my entire fat-loss and fitness system down to a handful of principles, two of the top contenders would be 1. do nothing that will harm your health or metabolism and 2. do everything possible to increase daily calorie burn through specific kinds of exercise activity and by building a faster metabolism.
As I like to say, the “slow” approach is really the faster one because it greatly increases your odds of actually keeping the weight off!
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