Is the HCG Diet Safe? How it Damages your Thyroid & Metabolism

Are you thinking about doing the HCG diet for weight loss?

If so you are probably wondering…

Is the HCG Diet safe?

Will it harm my metabolism?

Will it cause thyroid damage or make my thyroid function worse?

​And you are right to ask these questions before you undergo the treatment!

The truth is that the HCG diet can cause damage to both your metabolism and your thyroid function and I will explain it in this post.

As a physician, I’ve had the advantage of treating patients before, during, and after undergoing the HCG diet.

​I know that so many of you out there are desperate to lose weight and you’ll basically do anything to get there, but let me tell you this:

There is a better way to lose weight and it has nothing to do with the HCG diet. I will explain more about this in this article as well.

Let’s dive in…​

Table of Contents

Why You Shouldn’t do the HCG Diet if you want to Lose Weight

The problem with weight loss is that we are using a flawed model.

Our current paradigm says that in order to lose weight you must decrease the number of calories you consume and exercise more.

Doing this will allow your body to enter a state of energy balance which will result in calories and fat being burned in the process.

This all sounds well and good, the problem is that it just doesn’t work.

If you don’t believe me then just take a look at the success rate of calorie-restricted diets (of which the HCG diet is most certainly a part).

The data show that approximately 98% of people fail to maintain long-term weight loss on diets such as these.

So that means 1 of two things:

1. We either need to eat even less or exercise even more…

2. Or, just maybe we really don’t understand the real reason why we both gain and lose weight

​I tend to focus on the latter. 

In this model weight gain is primarily driven by hormonal abnormalities, NOT excessive consumption of calories.

Now, this doesn’t mean that food isn’t important.

On the contrary.

You see food and calories are considered information and they directly have an impact on your hormones themselves.

So let’s say you eat lots of refined carbohydrates, sugars, pasta, and pastries and you gain 20+ pounds.

Our current paradigm would suggest that this gain was due primarily to the increased amount of calories you consumed.

And while that is certainly part of the problem, it doesn’t explain everything.

In reality, the excess calories contributed to high insulin levels which sent the signal to your body to store excess energy as fat. 

​This hormonal dysregulation causes weight gain and hormone imbalances that directly lead to weight gain. 

So how does this apply to the HCG Diet?

Well, the problem is that simply reducing calories may temporarily result in weight loss, but it does nothing to fix the hormone imbalance.

So what happens?

You get hit with a double whammy:

Not only do you gain ALL the weight back you lost (because you didn’t treat the primary problem).

You have now also caused some further hormone imbalances (metabolic and thyroid damage) in the process.

​The bottom line?

If you are considering the HCG Diet you need to take a step back and read through the rest of this article so you have a better idea of WHY you are actually overweight in order to understand how to treat it. ​

The HCG Diet vs HCG The Hormone

​Before we talk about how the HCG diet can damage several hormones in your body we need to distinguish between the HCG diet and HCG the hormone. 

The HCG Diet is a calorie-restricted diet (to various levels) plain and simple. During the calorie restriction, patients use the hormone HCG to help boost weight loss in “hard-to-reach” places.

​Now compare that to the hormone:

The hormone HCG (which stands for human chorionic gonadotropin (1)) is secreted by pregnant women. 

​Now here is where things get interesting and why we need to differentiate between the two:

The ​HCG Diet is a calorie-restricted diet that will cause metabolic and hormone damage. 

Much of the bad name that the HCG Diet brings is wrongly associated with the hormone and it isn’t really fair.


Because HCG by itself is actually quite helpful.

Studies have shown that HCG the hormone, can actually help stimulate thyroid function (2) and actually increase thyroid hormone release (3). 

So now we are in kind of a pickle.

I just said that the HCG diet harms your thyroid, but that the HCG hormone itself actually can increase thyroid function.

This may explain why SOME (a small minority of patients) can actually go through the HCG diet without suffering major metabolic and thyroid damage.

This also probably explains why anyone with some baseline thyroid disorder that goes through the HCG Diet is left devastated.

​The point is this:

The HCG hormone itself has some uses as long as it is not paired with a chronic calorie-restricted diet.

In fact, I’ve used HCG by itself (without the diet portion) to help patients lose weight by boosting thyroid function and improving estrogen/progesterone levels. 

HCG can also be used safely to help improve fertility in both men and women (4) and it is an important part of male testosterone replacement therapy (to prevent testicular atrophy).  

The HCG Diet and Your Thyroid

​So now you may be asking:

What will happen to my thyroid if I undergo the HCG Diet?

First, you need to understand what the thyroid does and why it is so important. 

Your thyroid controls your metabolism and the amount of energy that you consume and burn at rest.

This is sometimes referred to as the resting energy expenditure (5) or the resting metabolic rate.

Does hcg diet cause hypothyroidism

​The resting energy expenditure is the single most important factor for determining if you will lose weight and if you will keep it off. 

This amount of energy consumed represents the MAJORITY of calories burned throughout the entire day.

And no – you can’t sit on a treadmill and seriously burn 1,000 calories, your body doesn’t work that way (if it did none of us would be overweight). 

So the amount of energy you burn on a daily basis just thinking, breathing and living is what really determines how and if you will lose weight.

And what you need to understand is that the HCG Diet actually REDUCES this number and this is how it damages both your thyroid function and your metabolism. ​

As little as 21 days of consistent calorie restriction is enough to reduce your metabolism by up to 40%. You can find the studies here (6). 

Does hcg diet cause hypothyroidism

What’s crazy is that we have known this since the ’90s.

Calorie restriction reduces your energy expenditure and your resting metabolism is what is responsible for the majority of weight loss maintenance.

So in a way you are basically shooting yourself in the foot when you reduce your calories hoping to lose weight.

You will lose some weight initially, but you will damage your metabolism in the process and then the weight will come right back on once you start eating normally.

​Now imagine doing this over and over again, each time your metabolism slows just a little bit. 

You went from burning 2,000 calories at rest to 1,800 after your first diet, then 1,600 after your second diet, then 1,400, etc., etc.

Now you are burning 1,000 calories at rest and the only way to even maintain your current weight is to eat that amount of calories.

Does this sound familiar?

This isn’t in your head, and you can actually measure the number of calories you burn at rest with a device known as indirect calorimetry.

Unfortunately just knowing your metabolism is damaged doesn’t tell you how to fix it, but we will touch on that later. 

HCG Side Effects

So what kind of OTHER side effects should you expect after undergoing the HCG Diet?

​We mentioned a couple above and we will go into detail on the others below. 

Negative side effects of the HCG Diet: ​

  • Damaged metabolism and metabolic function
  • Lower resting metabolic rate or resting energy expenditure
  • Damaged thyroid function with high reverse T3 and low free T3
  • Reduced progesterone levels lead to estrogen dominance
  • Reduced basal body temperature
  • Cold hands/extremities
  • Hair loss
  • Weight gain
  • Depression, anxiety, or other mood-related changes

​As you may have noticed many of these side effects mimic symptoms of hypothyroidism (you can see the full list in this post). 

​And that is definitely true. 

Metabolic damage and low thyroid tend to go hand in hand and share many of the same symptoms.

In addition, calorie restriction of any kind will lead to some very characteristic symptoms like changes in skin texture, hair loss, etc.

These occur as your body attempts to conserve energy for the more vital functions in the body and ​takes energy away from things that are less important or considered “cosmetic”. 

Now it’s important to realize that many of these symptoms are caused by the calorie restriction component NOT the HCG hormone itself.

They tend to get lumped together because both the Diet and the hormone are used together, but in reality, the side effects are quite different. 

As an aside, if you are using sublingual HCG drops all of your symptoms are due to calorie restriction and starvation NOT the hormone. 

The reason is that the sublingual HCG drops don’t actually get absorbed, so in effect, they are more like a placebo than anything else. 

​Below I’ve included some symptoms of the HCG hormone itself. 

Side effects of the HCG hormone shot:

  • Mood changes like anxiety or depression
  • Feelings of irritability or restlessness
  • Swelling of the extremities (typically lower legs and ankles)
  • Headaches or migraines (although symptoms HCG will get rid of these symptoms as well)
  • Other symptoms that mimic PMS or PMDD

​Now you might notice that many of these symptoms mimic symptoms you may experience with or around your cycle. 

And you would be correct because of how HCG works in the body.

In females, it can actually help stimulate ovulation and thus it may alter estrogen/progesterone levels leading to many of the symptoms above.

​This is why it can also be used to help reverse some of these problems and to improve fertility in certain patients. 

The HCG Diet, Thyroid Function, and Reverse T3

So what if you’ve already done the HCG diet once, twice, or even three times? What if you are experiencing many of the symptoms I mentioned above?

​The good news is that many of these symptoms can be treated. 

The damage from the HCG Diet hits the thyroid particularly hard, but it can be reversed and treated – but you have to know what you are looking for.

I’ve had the advantage of treating patients immediately after the HCG diet, during the HCG diet and I’ve seen the long-term effects of multiple rounds of the HCG diet as it relates to thyroid function.

Typically after the HCG diet, patients may have some or all of the following thyroid lab changes:

  • Low free T3
  • Low or mid-range free T4
  • Usually low TSH (less than 1 typically)
  • Very high reverse T3 (usually > 20) 
  • Low sex hormone binding globulin (or SHBG)

Below is an example of a patient who just recently underwent the HCG diet (30+ days in a row)…

Read more  Cretinism: The past, present and future of diagnosis and cure

Does hcg diet cause hypothyroidism
Does hcg diet cause hypothyroidism

You can see from this example the reverse T3 is very high at 41.1 and the sex hormone-binding globulin is low at 25. 

This means that the cells and tissues aren’t getting enough thyroid hormone. Period. 

​If you have labs similar to the ones above AND you have symptoms of hypothyroidism then there is a VERY high chance you are suffering from thyroid damage. 

How to Actually Lose Weight

This is all well and good, but knowing this how do you actually go about losing weight?

The truth is that you have to make sure you are attacking the RIGHT problem.

The majority of weight gain and weight loss resistance is from hormone imbalances.

In most patients, especially if they’ve done any calorie-restricted diet in their life (most of you have!) then you are most likely suffering from thyroid resistance to some degree.

In addition, as many as 50% of you (based on statistics) also have insulin resistance.

The combination of these two hormone imbalances causes most of the weight gain you may be experiencing. 

I’ve compiled step-by-step case studies that you can go over below. All of the patients have some degree of hypothyroidism as well as weight loss resistance:

  • 55 pounds lost over 6 months using WP Thyroid
  • 42 pounds lost over 3-4 months using T3 + Byetta
  • Diabetes and insulin resistance reversed in 3 months (and 40+ pounds lost)
  • 30+ pounds and 20+ inches lost over 6 months with before/after pictures in a Hashimoto’s patient

​Use these case studies to help you understand HOW to lose weight and notice how each patient has their own set of hormone abnormalities leading to weight loss resistance. 

What you need to remember is that each of you is quite different – which means that no two treatment plans will be the same.

What to do if you’ve Already Done the HCG Diet Multiple Times

If you’ve already done the HCG diet and you’ve been reading through this article then you fall into a special situation. 

Unfortunately, most patients don’t get to me until they’ve done considerable damage to both their thyroid and their metabolism, and the longer you go untreated the more difficult it is to reverse the problem.

But that is the point:

These problems CAN be reversed.

I’ve actually been able to treat people during the HCG diet and by giving them pure T3 I’ve been able to reduce many of the symptoms and prevent the majority of weight gain that many patients experience.

The single best thing you can do is to find a practitioner that is both willing to work with you and understands how hormones function in the body.

You don’t necessarily have to use pure T3 but some combination of medications that contains T3 may be necessary depending on how high your reverse T3 levels are. ​

In addition, you will most likely need to be tested for leptin resistance and treated if present as well. 

The next (and more difficult part) comes in treating your metabolism.

You can find helpful hints and tips on how to do this here.

The most important part?

STOP doing the diet and STOP calorie-restricting your body!

That will go a long way to fixing the problem. ​

Wrapping it up

The bottom line:

The HCG Diet can harm your metabolism and your thyroid function, ultimately leading to weight gain once you stop the diet.

The bigger problem is that the damage to your thyroid and metabolism is long-term (at least up to 6 years based on the biggest loser study (7)) and can be difficult to reverse.

If you are thinking about undergoing the HCG diet please read the risks carefully before you proceed.

I would also recommend a full hormone panel to determine WHY your body is actually gaining weight and then treating and reversing those problems. ​

Now it’s your turn:

Is your metabolism damaged after the HCG Diet?

Is your reverse T3 elevated as a result of calorie-restricted dieting?

Did the HCG Diet work for you? Why or why not?

Leave a comment below!​

Does hcg diet cause hypothyroidism

— Update: 13-03-2023 — found an additional article 5 Myths about the hCG Diet – Thyroid and Metabolism from the website for the keyword does hcg diet cause hypothyroidism.

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“The hcg diet will ruin your thyroid and your metabolism for LIFE and you’ll never be able to lose weight on your own without hcg AGAIN!”

End of article.

Oh wait, you want more?  Like how do I know this will happen?  Oh….well, er….uh….I don’t have any proof.

     Instead, let’s combine a belated (like SUPER belated) celebration of my 1 year anniversary off of the diet (it will actually be 2 years now in just a few months-) with addressing the 5 main negative comments made about the diet.

What I have is my results with the hcg diet- including this pic of me a year later after finishing this protocol.

     I became inspired to write this post after a fellow hcger was feeling a bit down on herself when she was recently told something similar to the above “rant” by her naturopath.  I hate to see people become discouraged by statements made thoughtlessly and without real merit.  So this article is for all you out there who have been bummed out or even scared by similar comments.

I actually began writing this article at my 1 year anniversary mark from being off the protocol, but you know how time flies- still, it’s worth celebrating, since my results prove the title of this blogpost entirely wrong.  I don’t have a model-perfect body, but I have a body I’m happy with and that I can easily maintain.

I totally GET that on the surface, if you just read the rules of the hcg diet and leave it at that, it sounds unhealthy.  It sounds extreme.  Yes it does.

I’d like to tell you a little story about surface appearances though.

Have I told you the story about the time I went on my very first backpacking trip at the age of 16?  I LOVE the outdoors…absolutely everything about it.  Except for the thought of large wild animals.  Oh yeah and mosquitoes.

But back to the large wild animals.  The first night it was very windy.  I knew it was windy.  Yet, while I lay in my tent in the dark, I was literally shaking uncontrollably with fear at the thought that the horrific movement happening to parts of my tent and horrific sounds were SURELY that of a bear.  SURELY!!  Finally, I couldn’t stand it anymore and roundabouts 2 a.m. or so probably, I grabbed my pot and stick that I’d been holding in a vice grip for the past hour and started banging it loudly while running outside my tent (not sure why I ran out of the tent- like that  really would have been safer if it really was a bear).

Did I mention I wasn’t backpacking alone?

Yep.  All the fam and friends (including my now husband, then not even boyfriend yet) were awakened.  Probably one of my most embarassing moments ever.

My point is that things are not often what they appear on the surface.  

And you won’t know this for sure about something until you really delve a bit deeper.

I know the rules of the hcg diet go against the generally-accepted-as-balanced-and-healthy-way-of-doing-things premise, but on looking deeper, you see that it doesn’t.

  • It will ruin your thyroid
  • It will ruin your metabolism (for LIFE)
  • The above will prevent you from ever losing weight again on your own
  • It’s a starvation diet and you will just lose a bunch of muscle
  • You will regain the weight because of the above

This is funny to hear because my experience has been the exact opposite.

     I’m not saying hcg is always the right choice for everyone and that it will always produce an amazing outcome 100% of the time.  Certainly not.

The HCG Diet, like anything, can be abused, and if not used properly, YES you can and will cause damage to your body. 

     Even then I wouldn’t call it lifelong damage- the body is actually pretty resilient and given enough time and proper care, can recover from a lot of things.  In fact, when you lose weight, you are having to recover from the effects of being obese for however long that lasted for you.

But done properly and mindfully, my experience at least, has been that hcg totally turned my life and body around – in a good way.  So let’s dissect each of these scare tactics one by one.

     I have had a thyroid condition for several years, caused by hashimoto’s thyroiditis (an autoimmune disease).  I didn’t discover it until about 4 years ago.  I was taking 87.5 mcg of t3 – aka Cytomel – thyroid medication prior to starting the hcg diet.  This is a pretty high dose of a pretty potent medication.  If any of you are dealing with similar hypothyroid issues, this is literally THE best resource online for getting yourself informed:  Stop the Thyroid Madness

After the hcg diet I’ve been on a fraction of what I was on before- I now take just 12.5 mcg of this same medication.  As of June 2014 I’ve actually been off all medication but I can’t say for sure that I don’t need that small amount, for this example’s sake, we’ll stick with the 12.5 mcg – it’s been I believe more than 2 years since I was on the higher 87.5 mcg dose.

That’s 1/7th of the medication I was taking.

Now I must mention that I also started up going to Crossfit in between my rounds of hcg and removed gluten from my diet, so I’m sure this played a role in the reduction of my medication.

Basic Answer to Scare Tactic #1: If hcg and the very low calorie diet (vlcd) had negatively effected my thyroid further (done the proper way, with healthy breaks between rounds), it’s seems highly unlikely I would have been able to make such a huge reduction in my thyroid medication like this long term.

I’m not saying hcg improved my thryoid – perhaps it helped, perhaps it had no effect.  I made so many other changes as well like I mentioned- the gluten, no more sugar, Crossfit.

But it’s obvious that my thyroid was not negatively impacted by the diet or there would be signs showing it did.

Do I think you can hurt your thyroid if you live on hcg for a year, consistently cheating, etc. – yes certainly. But that is not the way the hcg protocol was meant to be used.

Does hcg diet cause hypothyroidismWatch Vicki’s Full Interview here

What is a ruined metabolism?

     I’m not sure what the definition is exactly, but we’d probably all agree it involves getting to a point where you gain weight very easily, and have to eat less and less just to maintain your weight- less than someone else of a similar body weight/build would eat.  Usually when this happens, the person HAS to start counting calories because otherwise, eating a normal amount, they will gain weight.

Additionally I see the “for life” thing thrown in quite a bit when I did some google searching about ruined metabolisms.  This is scary of course to think about- the idea that one wrong move, and you will literally be stuck for the rest of your life having to eat less than you feel satiated with, and there’s nothing you can do about it because it’s not reversible. Yikes!

My experience

     Not only did I eat only 500 calories for every one of my 5 rounds of hcg total, I also ate as little as 300 calories at times– sometimes I was just that un-hungry (this is the #1 reason why the dosage of hcg you take is so important btw).

Because I don’t count calories, I can’t really tell you my daily caloric intake, but that alone is a good indicator.

First of all it varies- some days I eat more because I feel more hungry or because I worked out, and some days I actually purposefully intermittent fast for 18-24 hours.  The fasting I have probably done a total of maybe 12 days in the past year, so it’s not a big part of the picture.  My guess is I eat around 2000 calories a day (and remember I crossfit, so that allows me to eat more).

The best I can do is give you an example of what I ate the other day:

2 baked potatoes with maybe 4 tbs. of butter total.
3-4 oz of leg of lamb
2 large grapefruits
large salad with raw carrot and pinenuts + maybe 1.5 tsp. olive oil (guessing here)
a spoonful or two of sesame seed butter
3-4 oz of pastured raised Chicken- dark meat

I don’t know how many calories this is and I’m too lazy to look it up right now, but my guess is it’s FAR more than 1200 calories.  I’m going to say it’s maybe around 1800-2000 calories.  Don’t forget I’m 5′ tall and weigh 123-125lbs now.  And remember that is not what I eat every day- some days I eat far less because I’m busier and not as hungry.

I’m pretty sure any sane person who sees my above menu and knows my height and weight, would not say I’m having to under-eat in order to maintain my weight.

Basic Answer to Scare Tactic #2: Since I’ve maintained my fat loss from the hcg diet for a full year now almost 2 years, have not had to under eat to do so, and eat what I need/want (in a healthy way) to stay healthy, I don’t feel my metabolism has been affected negatively by the protocol.

And remember, this is coming from a person who BEGAN hcg with a thyroid problem (that I was being properly medicated for).  I would think someone who didn’t have a thyroid issue to begin with and did the protocol properly would fare even better.

Now it’s not like I finished the diet and then laid down on the coach and didn’t lift a limb to see what would happen over the next year though.  In keeping with my new body and new health goals, I have been crossfitting for two and a half years now (I took breaks from crossfit though when I was on my rounds).

Did Crossfit help my metabolism?  I think it would be pretty much impossible for it not to!  I think it’s a HUGE part of how “comfy” my body is able to stay where it’s at and even improve.  But even at that, I literally only spend 3 hours a week doing this exercise.  The remainder of the time I’m actually fairly sedentary.  No 2 hour sessions running on the treadmill.

I’m also not saying that everyone who does hcg will be able to eat the same diet as me.  A large number of the women who frequent my site are in peri-menopause or straight up menopause and hormones whether it’s too much or too little DOES affect how our bodies utilize calories and definitely can make maintaining weight more difficult.  But rather than give up, I’m glad hcg is here to have a way to combat this.

Let’s move on to the ruined metabolism FOREVER part.


     I feel the idea of a metabolism being ruined forever is a myth now.  Not for just the hcg diet, but for any diet really- even fasting.

Read more  How Does Milk Thistle Improve Thyroid Health?

Let me clarify- your metabolism WILL slow down if you fast for a length of time.

But it’s not permanent, and also doesn’t mean you’re damaging your body.  There are actually several books on fasting
I read recently that described the physiologic process your body goes through when you water fast and how the body does reduce the metabolic rate after a certain period of fasting (but at the same time it is also accomplishing some other amazing things like autophagy- a process where your body breaks down diseased/less than perfect tissues and eats them up, allowing your body to create new healthy tissue in it’s place), and that it then takes a period of weeks to return to normal- but it WILL return to normal, provided you do the right things to take care of yourself.

I know that’s sort of off-topic, but I mention it mainly because the notion of this extreme viewpoint that if you made a mistake when it came to your body the change would be PERMANENT is a little too much- hence why I called it a scare tactic.

The reason I feel so confident about this information now is because of the book: Fasting and Eating for Health: A Medical Doctor’s Program for Conquering DiseaseDoes hcg diet cause hypothyroidism, and my own long term results using hcg and using fasting at times.

Does hcg diet cause hypothyroidismWatch B’s Full Interview here

     IF this is true in certain cases, it’s most likely more a matter that the individual couldn’t lose weight without hcg to begin with- meaning there’s likely other hormonal imbalances like thyroid issues they have but are unaware of etc, in which case, doing the the diet changed nothing about their body’s ability to lose weight, positive or negative.  This protocol is not a replacement for addressing other things that are wrong in your body.

However, I’d like to share my recent experience that proves that, at least in my case, this scare tactic is not true.

I don’t think the definition of success from a diet means that you lose the weight and then never gain or lose a single ounce from that point forward forever more.

Anyone who does is either not being honest, or is amazingly more impervious to life trials than the vast majority of human beings on planet earth.  Good for THEM.  We are imperfect beings with imperfect lives.

I have multiple health conditions that have been going on 10 years that flare up from time to time, and at times this and other stresses have caused me to eat more than I should, or to eat the wrong kinds of foods, for a short period of time.  I have even experience weight gain for NO reason that I could pinpoint to any specific action on my part- meaning I was eating the same and working out the same, but my illness was making me feel unwell and my weight just shot up – meaning something had changed inside my body and was not functioning as optimally as it was.

To me the real success is how you learn to deal with errors you might make in your diet from time to time.

     So I have actually gained a few pounds at a few different points this past year.  But I also managed to lose the weight gained, on my own, without hcg.

My first error was right after my final hcg round ended- I jumped into P3 too quickly and as a result, even though I ended the round with just 21.3 lbs of fat, I immediately gained about 2 pounds of fat in the next few weeks.  I didn’t bother to try to re-lose this though, I was perfectly happy stabilizing and maintaining at a slightly higher weight, which I did well, staying between 23.5-25 pounds of fat for 5 months.  In the four months from April to July though I gained another 3 lbs of fat.  I WAS eating more than I should- I was feeling pretty down during these months and actually feel I did pretty well with my eating considering it all.  But that particular bodyfat test in July was a wake up call.  I had been maintaining a nice 18-19% bodyfat for several months, but now I was at almost 22% with over 28 lbs of fat (to keep it real, this is still a VERY good level of fat for a woman’s body, but the fact that is was increasing is what was bothering me).  At this point I made some changes-

I tightened up my diet by:
  • Periodically eating low carb for a week here and there
  • Intermittent fasting here and there for 18-24 hours at a time.  I probably did this 1-2x’s a week for a couple months.
  • Removed dairy as a trial (okay except for 1 tsp. of half n half in my black tea each morning, and butter).  My weight really started coming down without doing anything at that point.  I think this is because the dairy was causing inflammation in my body.

Follow up hydrostatic body fat test?  October 2013:  17.8% bodyfat, 22.15 lbs fat.  This is almost EXACTLY where I was at when I ended my final hcg round a whole year ago.  I managed to go from 28.32 lbs of fat to 22.15 lbs of fat, all on my own, between July and October.  A later body fat test from April 2014 showed I had dropped to 15% body fat, with 18.39 lbs of fat on my body (3 lbs of fat LESS than my end of hcg).  But just to be honest I didn’t maintain that for long.  Would have been nice.

Basic Answer to Scare Tactic #3:  I lost over 6 lbs of actual fat during a few months, without hcg.  I did not do a super hardcore diet on a daily basis during this time or anything, but just used the methods above AT TIMES throughout the past 3 months.  Weight loss possible the “normal way” after hcg? Check!

That’s huge because most weight loss is actually a combination of water, fat and muscle, so when someone says they lost 15 lbs with a diet, only a portion of that will be pure actual fat- maybe 8-10 lbs or something usually.

I think this protocol is great for losing larger chunks of weight.  Since I really only had a small amount to re-lose, and my health was on the better end at that point, it was worth it to me to see if I could save myself the loading, the vlcd, and the strict P3.  And it worked!

Does hcg diet cause hypothyroidismWatch Amy’s Full Interview here

     I actually talk about this whole subject in detail here:  Common concerns with the hcg diet.

What I have come to believe is that when DONE PROPERLY (there are a LOT of rogue hcg diet methods out there, meaning not on the original protocol- and I’m also not opposed to some alterations done mindfully) the body retains a normal amount of muscle mass for that person’s body height.

I found a GREAT blog called Barbells and Beakers that has compiled and explained a number of studies on this topic – one part I’d just like to quote on her blog from this post is:

“But if there’s so much science – and common sense – showing that you don’t lose muscle preferentially, where did it come from? Turns out a few studies showed a decrease in lean body mass (muscle) during a fast. Don’t worry, new science helped to remedy what may have been a misunderstanding. Turns out that majority of the “weight loss” from muscle was a loss of glycogen and water. Glycogen, for you non-bio nerds, is the stored form of glucose. So most of the loss of “mass” from muscle was water and stored glucose. Additionally, these same studies showed that about 14% of the energy from a fast came from protein, whereas 85% came from stored fat.

Basic Answer to Scare Tactic #4:  I have lost as much as 88% fat (of the total weight lost) on the hcg diet, proved through hydrostatic body fat testing.  Sabrina’s body fat testing showed she lost 93% fat on the hcg diet.

     That’s pretty amazing.  So because of my own good results and others with high percentages of fat loss that can be proved, I do feel that hcg helps the body spare lean muscle mass and favors more fat loss.

But this doesn’t mean a person will never lose muscle on the hcg diet. 

I actually did lose over 16 lbs of muscle/lean mass my very first round.  That’s pretty huge.  There could be two reasons for this.

1.  a very overweight person typically has a lot more muscle than someone who is a healthy weight of their same height.  Your body has to carry more muscle to carry the extra fat. 

So if you are starting out the hcg diet 50-100 lbs overweight, yes you will most likely lose some muscle.  But it never prevented me from maintaining my weight loss after the fact.  Actually, the easiest Phase 3 I had was after that first round- I was amazed how well my body just stabilized by just sticking to no starches and no sugars for the 3 weeks.  So to me this was a natural part of the process.

Just to give you an example, when I began this diet, I had 111 lbs of lean mass at 172 lbs (5’1″).  When I was in high school I weighed 102 lbs TOTAL.  Depending on your height and your frame size, there is a normal range of muscle and lean mass that you will have – in order to even BE a normal weight for my height and still be a healthy body fat percent (meaning not having so little fat that my body is compromised) I technically HAD to have less muscle.

If I still had 111 lbs of muscle, and I weighed what weight now which is really at the high end of a healthy weight for my height, about 125 lbs, that would mean I would be at 12% bodyfat.  Its pretty uncommon for an everyday, full grown woman to have a bodyfat percent that low and depending how it’s achieved, can be unhealthy.

2. I did a few things I shouldn’t have.  I drank diet coke everyday.  I ate coconut oil.

I’ll never know now if those two things caused me to lose more muscle on hcg than I should have- it’s certainly plausible.  I have never lost that much muscle on any subsequent round of hcg.

One last thing I want to mention here that I didn’t know before is that because muscles store a lot of water – actually kind of a water and sugar mixture called glycogen – body fat testing results ARE affected by water levels in the muscles.  I didn’t realize this before.  The reason I came to find this out was when I started having a few body fat tests close together- one right at the end of Phase 2, then another one about 3 weeks later.  During that 3 weeks I would gain like 6-7 lbs right away (I have done a few of my hcg rounds without fruits or melba making the diet VERY low carb which then depleted my natural muscle glycogen stores far more than usual) and would be amazed to find I had suddenly “gained” like 5-6 lbs of “muscle” in just 3 weeks doing all of like 5 workouts.  This couldn’t be all straight muscle fiber- this was mostly water- just my muscle’s glycogen stores refilling.  So you could take a body fat test right at the end of phase 2, before you’ve had a chance to eat more normally and have your glycogen stores refill, and it might appear as if you lost several pounds of muscle, when in reality, it’s just water.

Does hcg diet cause hypothyroidismWatch Sabrina’s Full Interview here

We’ve already debunked the other four tactics, so at this point, I’m just going to show you this:

November 5, 2012:  17.9% body fat, 21.3 lbs of fat, 119 lbs total, 97.5 lbs lean mass

October 10, 2013: 17.8% body fat, 22.15 lbs of fat, 125 lbs total, 103 lbs lean mass

April 2, 2014: 15.08% body fat, 18.39 lbs fat, 122 lbs total, 103.6 lbs lean mass

All stats above are from hydrostatic testing, which you can see here:

Basic Answer to Scare Tactic #5:  It has been a whole year almost 2 years.  Not only that, but I took several months of breaks between each of my other rounds as well, and consistently maintained 99.5% of my fat loss from those rounds easily too.  No calorie counting.  No under eating.  No having to be low carb for life.  I don’t eat low carb now at all in fact.  Reasonable working out-  3 hours a week (course, I don’t know if Crossfit could really be called reasonable).

Does hcg diet cause hypothyroidismWatch Jenny’s Full Interview here

    • Get rid of sugar.  Replace with stevia.  Seriously- after awhile you won’t even remember or miss it.
    • VARY how much you eat by becoming more in tune with your body.  It’s okay to eat more some days if you feel like it.  But try to start taking notice of days you feel less hungry- perhaps a day you’re super busy- it’s okay to eat less or even not at all those days- seriously- I am so freed by no longer fearing that my metabolism will crash if I don’t eat for a few hours.  It’s almost laughable now to think how duped I was by this info.
    • Have TACTICS for fixing a minor weight gain.  Intermittent fasting.  Low carb for a week.  Remove a food group you’re suspicious of.  Nothing has to be permanent- these are all just things to try- you will discover some of them work wonderfully well for correcting dietary errors.
  • Address thyroid and adrenal issues.  Don’t take this lightly.  Sometimes I get emails from people who know they have a thyroid condition but don’t take medication and they wonder if they will be able to maintain their weight loss after hcg.  I doubt it.  hcg doesn’t fix everything else wrong inside us.  I actually am experiencing this problem right now.  My lyme disease has been acting up and I have a small amount of what I deem unwarranted weight gain, while eating the same foods and same crossfit lifestyle that I’ve been living that has kept me at the same weight for the previous several months.  I know my hormones are off.

Prior to starting HCG

    • I was severely hypothyroid (details below)
    • I had Hashimoto’s autoimmune disease (involves the thyroid).
    • I took 87.5 mcg of Cytomel aka T3- a thyroid medication that is essentially active thyroid hormone.  This was the amount medically prescribed to me by a real doctor.  This is a very high dose of a very potent medication- very few people take this high a dose.  Very few people even take active thyroid hormone.  Most people are on completely different thyroid meds that are not nearly as potent (aka Synthroid, T4, Levothyroxine, Levothroid, Levoxyl, etc).
    • I gained weight to the tune of 172 lbs.
    • Wore a size 18 (only 5’1″ tall here people)
  • 34.5% bodyfat – 59 lbs of fat on my body – tested by by hydrostatic body fat testing

After the HCG Protocol

    • I am 124-126 lbs
    • I’ve been between 18-19% for almost the entire year since finishing hcg – again proved by hydrostatic body fat testing.
    • I have maintained an approximate 50 lb weight loss from hcgfor close to 2 years.
    • I take 12.5 mcg of Cytomel thyroid medication.  A fraction of what I used to take.
    • I don’t count calories
    • I eat carbs – baked potatoes, organic corn tortillas, fruit, rice bread, etc.
    • Maintaining my weight is not difficult

Read more  10 ways to overcome fatigue with a low thyroid

    • I still have Hashimoto’s- it’s not really reversible, but the testing levels for it are far lower than before.
    • I recently gained about 6 lbs of fat and lost it all on my own, without hcg, simply by tightening up my eating and doing a little intermittent fasting.  This seems to debunk the notion of never being able to lose weight without hCG again.
  • Had an April 2014 body fat testing at 15% body fat – the lowest I can remember.

I feel that if the hCG protocol really did ruin your thyroid and metabolism, all of the above would simply not be possible.

It might be tempting for some to say I’m making this stuff up, but I simply have too many youtube videos cataloging my entire hCG journey and too many dated body fat tests for there to be any doubt that, yes, I lost close to 50 lbs, and yes, I lost it with hCG, and yes, I’ve maintained it for close to 2 years.

But when you are new to the hCG diet and haven’t had your own personal success story yet, it’s far more difficult to feel as confident- you don’t have that ultimate proof in your own experience to stand on.

They most likely point to people they know or that they’ve seen online who have gained weight back after losing it with hCG.  Yes this totally happens.  All the time.  Even happened to me once!  See a few clips from my failure after Round 2 in this hcg video – it’s about 2 minutes into the video, so just forward it.

But guess what?  This happens every day, with every diet.  It’s not the diets that are the problem.

It’s our own ability to make long term changes.

I had one round that I regained the weight lost.  I had 4 rounds where I maintained the weight lost.  And now it’s been almost 2 years.

If your definition of a healthy diet is only one that will allow you to live at fast food joints upon completion without gaining weight, dream on.

What we need to provide people more help with is SUPPORT for making those long term changes.

It can be a difficult, emotionally trying experience.  It sure was for me.

And that’s what is all about.

Related posts:

— Update: 13-03-2023 — found an additional article Can HCG for Weight Loss Hurt Your Thyroid? from the website for the keyword does hcg diet cause hypothyroidism.

Does hcg diet cause hypothyroidism

Last Updated on January 8, 2022

Weight loss options are numerous for people who want to slim down and keep their weight in a healthy range.

While excess weight can be stubborn, a good strategy is all that it takes to slim down and decrease the risk of many health conditions.

It’s not uncommon for people to try with HCG; you’ve probably heard about it or thought of doing the same to lose weight.

But what are the consequences of HCG, and is it harmful to the thyroid gland?

What is HCG?

Although HCG is a widely used term, most people are not quite sure what it represents. Before we can even begin discussing HCG for weight loss and its potential impact on the thyroid it’s useful to address it first.

HCG stands for human chorionic gonadotropin, and it is a hormone produced mainly during the pregnancy. The primary function of HCG is to stimulate the corpus luteum to secrete progesterone in order to maintain pregnancy. Corpus luteum is a temporary structure or a mass of cells formed in an ovary to produce progesterone during the pregnancy.

Certain amounts of HCG are also produced in other parts of the body, such as the liver, pituitary gland, and the colon[i].

Why is HCG popular today?

Chances are you have probably seen HCG everywhere today. People talk about their experiences online, there are tons of articles that instruct people how to take and inject HCG, and whatnot.

This trend shows no signs of slowing down, and it is impossible not to wonder why. Generally speaking, HCG is used to treat fertility problems and help the couples conceive.

But people across the globe have started using HCG for purposes that are not its initial function. Weight loss is one of them.

HCG for fertility problems is available with a prescription only. That is the only use of HCG approved by the FDA. It’s useful to bear in mind that HCG is also not approved for the over-the-counter use, and FDA emphasizes it is not for weight loss[ii]. However, HCG in the form of dietary supplements is widely available, and people across the globe use it to slim down.

What is the HCG diet?

The whole idea of HCG for weight loss originated in 1954 when Albert Simeons, a British doctor, suggested the HCG diet could help people slim down. Today, the HCG diet is widely popular, and it consists of two main parts: ultra-low calorie intake of 500 calories a day and injecting HCG or taking it in other forms.

The reason why HCG is considered beneficial for weight loss is that it’s a protein-based hormone which can speed up the metabolism and allow people to lose weight and retain their muscle mass. Advocates of the HCG diet claim they lose fat, but not muscles.

Current evidence on this subject does not support the claims that the HCG diet can cause significant weight loss because of the hormone itself. People lose weight due to significant calorie restriction and not because of HCG[iii],[iv], studies show.

People who want to try the HCG diet need to adhere to three phases.

First is the loading phase, where it is necessary to start taking HCG and consume high-calorie and high-fat foods for two days.

Second is the weight loss phase characterized by using HCG and lowering calorie intake to 500 calories a day for three to six weeks. This accounts for two meals a day.

Next is the maintenance phase, where a person stops taking HCG and increases food consumption gradually. But this doesn’t mean it’s okay to eat everything and anything; people still need to avoid starch and sugar for three weeks.

Can HCG affect the thyroid?

HCG has become a hot topic later as an increasing number of people use it for one reason to another. But when we are talking about HCG for weight loss, it’s also important to discuss whether it could have an unfavorable impact on the thyroid gland.

Not many studies have been conducted on this subject, and hopefully, we can expect that to change in the near future. The ever-growing popularity of HCG should call for further research on an array of subjects.

Hyperthyroidism risk

Korevaar et al. conducted a study whose main objective was to determine whether HCG could be a risk factor for some thyroid disease. For the purpose of the study, scientists measured HCG and thyroid hormone levels in 5435 pregnant women.

Results, published in the journal thyroid, showed that higher HCG levels were associated with an elevated risk of subclinical and overt hypothyroidism. This particular study found that HCG levels weren’t linked with subclinical hypothyroidism[v].

HCG diet vs. HCG hormone

When we are talking about the impact of HCG on weight loss on the thyroid gland, it is important to distinguish the line between the HCG diet and HCG hormone on its own. HCG diet, as previously mentioned, is indicated by significant calorie restriction and could be bad for our health in more ways than one.

On the other hand, the hormone on its own can be quite helpful, actually. Evidence shows that the HCG hormone has the ability to stimulate thyroid function[vi] and it can increase the release of thyroid hormone[vii]. These particular benefits of HCG may explain why some patients can go through the HCG diet without suffering damage or any kind of dysfunction to their thyroid gland.

How can the HCG diet affect the thyroid gland?

As seen above, HCG itself can be beneficial for the thyroid gland. But if HCG is a major component of the HCG diet, then what makes it so bad in this scenario?

The truth is, the negative impact on the thyroid gland here is mainly due to severe calorie restriction and not the hormone itself.

The thyroid gland has many roles in the body, including the regulation of metabolism and the amount of energy we eat or burn at rest i.e., resting energy expenditure or metabolic rate. The resting energy metabolic rate is the most important factor that determines whether we will lose weight and manage to keep it off.

Now let’s go back to the HCG diet; it decreases the resting energy metabolic rate and thereby slows down the metabolism and thyroid function. In order to slim down, you need to speed up the metabolic rate. Low thyroid function leaves us with an insufficient amount of thyroid hormones that our body requires to work properly.

HCG diet may also have various adverse reactions such as:

  • Hair loss
  • Cold hands and feet
  • Weight gain
  • Depression, anxiety, and other mood changes
  • Decreased basal body temperature
  • Damaged thyroid function (high rT3 and low free T3)

Take a look at the symptoms above. Do they remind you of anything?

Hypothyroidism can also lead to weight gain, hair loss, cold hands, depression, and other symptoms. The similarity is not a coincidence in this case. Low thyroid function and metabolic damage go hand in hand. Remember, thyroid regulates metabolism!

Do all people have thyroid damage due to HCG or HCG diet?

The use of HCG and HCG diet has become a major trend over the years, so you’re probably worried about your thyroid gland.

Above in the article, it was mentioned that the adherence to the HCG diet could induce HCG damage not due to the hormone itself but as a result of severe calorie restriction. That being said, it is important to point out that all people are different and their body reacts to HCG and HCG diet in a different manner.

Some people may not have thyroid damage on this diet. For example, one blogger reported that the HCG diet helped lower the dose of thyroid medications she had to take for Hashimoto’s thyroiditis.

She was taking 87.5mcg of T3, Cytomel before she started with the HCG diet. Cytomel is a powerful medication, and 87.5mcg is a pretty high dosage. After the HCG diet, her daily dose of Cytomel was reduced to 12.5mcg. As of June 2014, she has been off all medication.

This seems promising, but you should also bear in mind the blogger does not specifically know what helped reduce the drug dosage i.e., whether it was an HCG diet or something else.

Is it possible to reverse thyroid damage caused by HCG?

At this point, you’re probably wondering what happens when thyroid damage occurs due to the HCG diet. Is it possible to reverse it?

If you have used HCG or adhered to the HCG diet, it would be practical to see your healthcare provider and consult about thyroid health. Your doctor may order blood tests to inspect the levels of thyroid hormones.

If the damage has, indeed, occurred, the doctor will probably advise you to stop taking HCG/following the HCG diet. That is the first step! It is entirely possible to reverse the damage, but you need patience, strong willpower, and healthy lifestyle choices.

The complete management of this problem depends on the severity of the damage. For example, the doctor may order tests to analyze other hormone levels in order to propose necessary measures to speed up metabolism. You may need to consume a well-balanced diet and avoid restricting your calories severely.

In cases with severe damage, patients may need to take thyroid hormone replacement, but this isn’t a rule. In other words, if your thyroid damage is not serious, you won’t have to use medications. Lifestyle modifications could be enough.

HCG products

HCG injections are available with doctor’s prescriptions only, but nowadays, there are many HCG products available as supplements and thereby sold in the over-the-counter form. Caution is needed before the purchase.

Many products are presented as natural and effective solutions, but the market of dietary supplements is not strictly regulated, and things aren’t always as they seem. Do a little research before you buy, avoid scam-like brands and products, go through customer reviews, and make sure you opt for a product made by a reputable brand.

Healthy weight loss

Weight management is important for good health and wellbeing, particularly if you also have some thyroid problems. Conditions affecting the butterfly-shaped gland can cause weight fluctuations, so you may feel inclined to try out different solutions to keep it under control. Healthy weight management is entirely possible and only requires a few lifestyle adjustments, such as:

  • Don’t starve yourself and skip meals
  • Eat-in moderation
  • Prioritize a well-balanced diet rich in fruits and vegetables, nuts and seeds, and other nutrient-rich items
  • Reduce intake or entirely avoid heavily processed and refined foods
  • Quit smoking
  • Be proactive about thyroid condition management
  • Exercise regularly and increase activity levels
  • Meditate or find some other stress management strategy
  • Get enough sleep
  • Stay hydrated throughout the day, but opt for water rather than sugar-laden store-bought fruit juices


HCG has become a frequently mentioned term lately as millions of people around the globe use it to lose weight or for some other purposes besides the initial fertility treatment role.

HCG is also used as a part of the HCG diet for weight loss. The influence of this hormone on thyroid can be quite complex. While HCG on its own may help weight loss, the diet can damage thyroid and induce symptoms of hypothyroidism.

Before you start using HCG or following the HCG diet, make sure to consult the healthcare provider about all their advantages and disadvantages.


[i] Betz D, Fane K. (2019). Human chorionic gonadotropin (HCG). StatPearls. Retrieved from:

[ii] Zeratsky K. Has the HCG diet been shown to be safe and effective? Mayo Clinic. Retrieved from:

[iii] Bosch B, Venter I, Stewart RI, Bertram SR. (1990). Human chorionic gonadotropin and weight loss. A double-blind, placebo-controlled trial. South African Medical Journal, 77(4):185-9. Retrieved from:

[iv] Stein MR, Julis RE, Peck CC, et al. (1976). Ineffectiveness of human chorionic gonadotropin in weight reduction: a double-blind study. American Journal of Clinical Nutrition, 29(9):940-8. Doi: 10.1093/ajcn/29.9.940. Retrieved from:

[v] Korevaar TI, de Rijke YB, Chaker L, et al. (2017). Stimulation of thyroid function by human chorionic gonadotropin during pregnancy: a risk factor for thyroid disease and a mechanism for known risk factors. Thyroid, 27(3):440-450. Doi: 10.1089/thy.2016.0527. Retrieved from:

[vi] Kennedy RL, Darne J. (1991). The role of HCG in the regulation of the thyroid gland in a normal and abnormal pregnancy. Obstetrics and Gynecology, 78(2):298-307. Retrieved from:

[vii] Kraiem Z, Sadeh O, Blithe DL, Nisula BC. (1994). Human chorionic gonadotropin stimulates thyroid hormone secretion, iodide uptake, organification, and adenosine 3′,5′-monophosphate formation in cultured human thyrocytes. Journal of Clinical Endocrinology and Metabolism, 79(2):595-9. Doi: 10.1210/jcem.79.2.8045981. Retrieved from:


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