The “HCG diet” is very simple:

You eat 500 calories per day, and you inject or ingest a hormone called human chorionic gonadotropin (hCG), which is supposed to instruct your body to burn fat, not muscle.

It was started in the 1950s by a British physician, and it has enjoyed a nice resurgence of popularity thanks to hucksters like Kevin Trudeau (whose weight loss shenanigans got him a $5 million fine from the FTC and 3-year ban from infomercials), and “diet and pill of the day” pseudo-gurus like Dr. Oz.

People generally resort to the HCG diet for one, simple reason:

It results in rapid weight loss.

There’s no denying that it “works” in that sense–yes, you will lose weight, and yes you will lose it quickly.

HOWEVER…there’s more to this story. The HCG diet is not everything it’s cracked up to be, and is not advisable even as a temporary way to “jump start” your weight loss.

Let’s look at why.

HCG Doesn’t Help You Lose Weight, Preserve Muscle, or Feel Better

One of the big selling points of the HCG diet is the claim that the hormone will cause your body to burn fat and preserve muscle. There are also often claims about it blunting hunger and simply making you feel good.

Well, these claims have been repeatedly and categorically disproved in scientific literature.

Here’s how the scientists behind this definitive meta study of several decades of research on HCG and weight loss (24 clinical trials in all) summarized their findings:

“We conclude that there is no scientific evidence that HCG is effective in the treatment of obesity; it does not bring about weight-loss of fat-redistribution, nor does it reduce hunger or induce a feeling of well-being.”

As if that weren’t enough, you should also know that in 2011, the FDA began yanking off the market the pills, drops, and sprays containing hCG, denouncing them as “fraudulent and illegal.”

And what did the scammers do in response?

They started selling “hormone-free” pills, drops, and sprays that contain a mixture of amino acids that are claimed to deliver the same benefts.

Yeah, right.

So if HCG is worthless for weight loss purposes, then what about eating 500 calories per day? Is that a good way to lose weight?

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The Truth About Very-Low-Calorie Diets and Rapid Weight Loss

Most weight loss diets are marketed in the same way:

LOSE X POUNDS IN Y DAYS!

The larger X is, and the smaller Y is, the more excited people generally get. They figure they can do anything for a few weeks if it means losing 10, 20, or even 30 pounds.

There’s a kicker, though:

Rapid weight loss is deceptive, is often followed by rapid weight gain, and can even harm your health.

How so?

When you restrict your calories, whether moderately or severely, a fair amount of the weight you initially lose is simply water.

You’ve probably heard this before, but you may not know why.

It boils down to your body’s utilization of a substance known as glycogen, which is a molecule stored in the liver and muscle tissue that can be used for the generation of cellular energy.

Your body produces glycogen from carbohydrate you eat, and every gram of glycogen requires 3-4 grams of water for storage.

When you restrict your carbohydrate intake, glycogen levels decrease, which also decreases the amount of water you hold in your body. The less carbohydrates you eat, the greater the effect.

As most very-low-calorie diets have you eating little-to-no carbs, the water loss can be quite significant.

Yes, you can lose 10 pounds in 5 days, but don’t think that’s primarily fat–it’s mostly water. In one study, subjects ate 300 calories per day for 36 days, and in the end, water accounted for 21-31% of total weight lost.

There’s more, though. What happens when you start eating again, and increase your intake of carbs?

That’s right, your glycogen levels quickly rise again, and with that comes a rapid increase in water weight.

This can be quite baffling and discouraging, and has led many people to believe the severe caloric restriction “didn’t work.”

Screw it then, bring on the pizza, and so begins the spiral of regaining any fat actually lost while dieting. (More on that in a minute…)

When you severely restrict your calories, you don’t just lose water and fat–you lose muscle too.

This is yet another reason why just praying for the scale go down isn’t enough.

Large caloric deficits induce muscle loss, and the larger the deficit, the more muscle you lose.

This is why many women wind up with the dreaded “skinny fat” body after several rounds of starvation diets–they just lose too much muscle along the way.

This isn’t just bad for your physique, either. Many people don’t know that the amount of muscle you have actually has a direct impact on your health.

Increasing our body’s lean mass…

  • Accelerates metabolism.
  • Bolsters the immune system.
  • Decreases risk of chronic disease.
  • Improves bone health.
  • And more.

Believe it or not, muscle strength alone is a reliable predictor of all-cause mortality. Yes, the weaker your body’s muscles are, the shorter your life span.

When you consider the fact that you naturally lose muscle as you age, you can see how important it is to combat this with exercise and proper nutrition, and how unhealthy it is to burn up muscle with starvation diets.

Severe caloric restriction often comes with severe hunger and discomfort.

This shouldn’t really come as a surprise, but you feel pretty miserable when you barely eat.

Sure, you can supplement with fiber to reduce hunger, but don’t expect it to make a huge difference. Starving sucks, period.

  • Your energy levels plummet.
  • You have intense cravings for food.
  • You find it harder and harder to focus.
  • You can feel depressed
  • And more.

Suffering like this really isn’t worth it when you can just follow a moderate weight loss regimen and lose weight without any physical or psychological stress.

Many people slowly, or quickly, regain the weight they lose on a very-low-calorie diet.

Even if someone has the will to defy their body’s needs for energy and tough it out for a month or two of starvation…

Eventually they stop, and they can’t wait to eat. And oh, do they eat.

This results in the rapid increase in water weight discussed earlier, and as the overeating continues, a slow–or not so slow–return of the fat lost while dieting.

Unfortunately, however, the muscle lost stays lost, so in the end, many people utilizing starvation diets accomplish nothing more than burning up some muscle as well as their nerves.

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What is Healthy Weight Loss?

Here’s what healthy weight loss looks like:

  • Slow but steady weight loss. You should lose between .5 – 2 lbs per week depending on your current body fat percentage.
  • Little-to-no muscle loss. You still experience the initial “whoosh” of water weight, but after that, nearly 100% of weight lost should be from fat.
  • No real hunger issues. You may wish you could eat that steaming pizza or frosty ice cream, but you should never have to suffer through major hunger pangs.

When you lose weight healthily, it’s an easy, enjoyable ride, really. And fortunately, it’s very simple as well.

If you want to learn how to lose weight healthily, check out my article on flexible dieting, which is, in my opinion, the absolute best way to go about it.

What do you think about the HCG diet? Have anything else to add? Let me know in the comments below!

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