How Sex Hormones Affect Weight

If you’re like most of us, you’ve probably been told that weight loss or gain is simply an equation of calories in, calories out. Eat less, move more. 

But that doesn’t tell the full story – regulating hormones and finding your unique hormonal balance is KEY to achieving optimal body weight.

What are Hormones, and Which Ones Affect Your Weight?

Let’s back up for a second. What are hormones in the first place?

Think of hormones as messengers that your brain uses to communicate with your cells. Menstruation, for example, is due to hormones that instruct your ovaries to release an egg. 

There are lots of types of hormones that may affect your weight, like thyroid hormones, “hunger” hormones, and sex hormones. Today, we’ll be looking at sex hormones’ role in weight regulation.

There are lots of sex hormones in the body, but today we’ll be focusing on the three main ones: testosterone, progesterone, and estrogen. Each of which apply to both men and women. 

Testosterone: Ladies, This One’s For You Too

You might have heard of testosterone in the context of masculinity – but did you know women need testosterone too? 

Testosterone is a hormone that promotes cell growth – which is important for both men and women. Men need it in higher amounts than women do, however. It’s important that you have a balanced amount of testosterone – not too much and not too little. 

Testosterone in Men

In men, testosterone contributes to: 

• • Male sex characteristics, like facial hair and a deep voice

• Development of muscle tone 

• • Bone mass regulation

• Fat distribution
• Blood cell levels

Clearly, testosterone plays an important role in men’s health. If a man has too little testosterone, he may experience several health complications. These include: 

• • Reproductive health complications: low sex drive, erection difficulty, low semen volume, smaller testicles
  • Hair loss
  • Fatigue
  • Decreased bone mass
  • Mood changes
  • Affected memory
  • Low blood counts

• Loss of muscle mass
• Increased body fat

But how are these health complications related to weight? More on that in a second. Let’s look at how testosterone operates in women first.

Testosterone in Women 

Women need less testosterone than men, but they still need it. In women, testosterone contributes to: 

• • Bone health
  • Development of strength (specifically in the tendons)

• Development of muscle tone
• Regulation of the adrenal gland (adrenaline!)
• Proper development of reproductive tissue

Contrary to popular belief, testosterone is healthy in females! If a woman has too little testosterone, she may experience health complications. These include:

• Lowered sex drive
• Low bone density
• Trouble developing muscle
• Depression
• Weight gain

But too much testosterone in women can also be an issue, especially for weight regulation. Too much testosterone causes:

• Increased body fat, especially around the midsection
• Balding
• Acne
• Irregular menstrual cycles
• Mood swings
• Low sex drive

So it’s clear that the right amount of testosterone is vital to men and women’s overall health. Let’s dive into how that affects body weight.

Testosterone and Weight

We saw that testosterone is important to development of muscle tone in men and women in the bullet points – and muscle tone is key to weight regulation. Why?

Well your lean body mass – how much muscle you have – corresponds to your metabolism. The more muscle you have, the higher your metabolism will be. And if your goal is to lose weight, having a high metabolism will make it easier to shed fat. 

So maintaining your muscles is key to weight loss – and therefore, testosterone is key to weight loss as well. 

Notice that in men, not having enough testosterone leads to a loss of muscle mass and an increase in fat. That may not lead to weight gain, per say – but it’d be more likely that he would, since it’d lead to a decrease in metabolism. 

In women, it’s pretty clear cut – too little testosterone directly leads to weight gain. And, notably, it leads to trouble gaining muscle – which indicates that the weight gain will most likely be from an increased amount of fat. 

Too much testosterone in women does not specifically lead to weight gain, but it does increase the amount of fat a woman has, particularly around her midsection.

It’s apparent that having the right balance of testosterone in both men and women – not too much, and not too little – is important to weight maintenance. 

If you are trying to lose weight but have imbalanced testosterone levels, your weight loss process will most likely be stopped or slowed. 

Estrogen: Men, This is For You Too

You’ve probably heard of estrogen before. Pop culture associates it with women and PMS, but did you know men need estrogen too?

Estrogen is a set of hormones that are key to reproductive health in both men and women. It’s primarily a female sex hormone, but men also need it in smaller amounts.

Estrogen in Men

In men, estrogen is important for:

• Libido 
• Erections
• Sperm production
• Development of male sex characteristics (if testosterone isn’t balanced with estrogen, male sex characteristics will not develop properly)

It’s apparent that estrogen is important for male health. But too little or too much can cause problems. Having too much or too little estrogen causes the same symptoms in men, like:

• • Infertility
  • Erectile dysfunction
  • Slowed growth, or delayed puberty
  • Gynecomastia (more breast tissue development than normal)
  • Hair loss
  • Trouble focusing

• Lowered muscle mass

Like we talked about with testosterone, maintaining muscle is important for a healthy metabolism and body. More on estrogen and weight in men in a minute – let’s look at estrogen in women first.

Estrogen in Women

Women need much more estrogen than men do. In women, estrogen contributes to:

• Proper development of female reproductive traits, like menstruation and fertility
• Breast fat levels
• Prevents bone loss
• Enhances brain function
• Prevents inflammation
• Increased body fat levels, particularly fat patterning in the lower body, which is good for pregnancy

You might’ve seen “increased body fat levels” and thought you’d want less estrogen in your body to lose weight – but that’s not the case. Having too little estrogen actually causes weight gain, among other things, like: 

• • A lack of vaginal lubrication
  • Increased UTI incidence
  • Irregular or absent periods
  • Mood swings 
  • Breast tenderness
  • Headaches
  • Depression
  • Trouble concentrating
  • Low bone density
  • Fatigue

• Weight gain

So, having too little estrogen isn’t helpful. What about too much estrogen? You guessed it – we don’t want that either. Too much estrogen can cause:

• • Bloating 
  • Tender breasts
  • Low libido
  • Irregular menstruation
  • Increased PMS
  • Headaches
  • Anxiety
  • Hair loss
  • Cold hands or feet
  • Fatigue
  • Memory issues

• Weight gain

Having too much or too little estrogen leads to weight gain – so that’s not ideal for weight loss. 

But what about its role in increasing fat storing in women?

Well, it’s important that women have more fat on the body than men do, and to have breast fat. Don’t get scared of the increased body fat levels that estrogen contributes to – it’s healthy and necessary for fertility! You can still be at a healthy weight while having enough estrogen.

But would that slow a weight loss process? Let’s look at how estrogen plays a role. 

Estrogen and Weight

For both men and women, it’s clearly important to have the right balance of estrogen: not too much and not too little.

In men, too much estrogen primarily causes fat storage in breast tissue and loss of muscle mass. Like we talked about with testosterone, that lowered amount of muscle mass will lower metabolism – thereby making weight loss more difficult.

In women, it gets a bit more complicated than that. Some aspects of estrogen actually promote weight loss, but others may make fat loss difficult. 

Let’s start with the good news (and buckle up, there’s a lot of it!): 

• It increases AMPK, an enzyme that enhances the use of fat for fuel 
• It increases insulin sensitivity, which promotes fat loss
• It prevents inflammation, which promotes fat loss and proper digestion
• It helps to regulate leptin, a hunger hormone important to fat loss

So some aspects of estrogen definitely promote fat loss – but others aspects do the opposite:

• It thickens connective tissue in the skin, which is the primary cause of cellulite. The visibility of cellulite diminishes with decreased body fat percentage, as well, so as you lose weight, that aspect of estrogen won’t affect you much. 
• In combination with high fat intake, estrogen may negatively impact thyroid levels. And the second aspect of the two may be mitigated with monitored fat intake, and by making sure that most of your fat comes from plants. 

Progesterone

And lastly, let’s touch on progesterone. It’s not as sensationalized as estrogen and testosterone, but it’s arguably just as important!

Progesterone is a hormone key to reproductive health in both men and women. Like estrogen, women need much higher amounts than men do. 

Progesterone in Men

In men, progesterone is vital for sperm development. But for this one, we’re going to focus on progesterone in women – it plays a much more significant role in female weight than male weight.

Progesterone in Women

In women, progesterone is necessary for menstruation and pregnancy. It’s released from the ovaries after ovulation (when a woman releases an egg from her ovaries). Think of it as your fertility hormone!

For pregnancy, the body stores fat to make sure it has enough energy to feed a growing baby. And since progesterone is our pregnancy and fertility hormone, it does play a major role in storing fat. Let’s take a look at its relationship to weight.

Progesterone and Weight 

On paper, progesterone doesn’t sound awesome for weight loss:

• It increases fat storage (for pregnancy)
• It causes hunger and cravings when it’s released (right around your period)
• It increases LPL and ASP, enzymes involved in fat storage

And you’d be right to think, like the other hormones, that too much progesterone could slow your weight loss process. Too much progesterone causes:

• Decreased insulin sensitivity (bad for weight loss!)
• Increased fat storage
• Decreases ability to build muscle

At this point, progesterone might seem like the devil when it comes to weight loss. But you’d be better off balancing your progesterone than trying to lower it! 

That’s because too little progesterone leaves room for estrogen to dominate – meaning your body would (basically) produce too much estrogen to compensate for the loss of progesterone. Symptoms of low progesterone include: 

• Headaches
• Mood swings
• Irregularity of menstrual cycle
• Breast tenderness
• Weight gain

So, you guessed it – you want a proper balance of progesterone as well!

The Bottom Line: Balance Your Sex Hormones 

It’s apparent that having too much or too little of any sex hormone may make it difficult to maintain or regulate your weight, especially if you’re trying to lose weight. 

Remember that having the correct amount of these hormones are also important for reasons other than just weight maintenance, like mental health, bone health, fertility, and more.

Curious if your own sex hormones are out of whack?  It’s worth getting them tested to see what’s going on. Contact Kylie and Kate to get help with testing and treating hormonal imbalance.