Master The Female Metabolism – The Ultimate Guide To Female Fat Loss

In working with thousands of patients over the years, I can tell you with certainty that women are very different than men metabolically and female fat loss is, in many ways, more complicated...

Beyond that, female fat loss after forty is different than fat loss in women between 20 and 40 years old. In this comprehensive article, we're going to cover, in detail how a woman's metabolism is different than a man's and how to shift your lifestyle to account for these differences so that you can get the scale moving in your favor no matter your age! 

This is a "meaty" article, no doubt, my goal is to make it the most comprehensive article on female fat loss on the web, and as more data gets published, I will continuously update this article, so I really encourage you to sign up for email updates so that you can be alerted when new research comes to light about our female fat loss diet plan and the female fat loss workout recommendations. 

So, let's get started...

In our younger years, when estrogen is highest, lipoprotein lipase is inhibited and this means we store less fat. As we progress past 30 and ultimately into menopause, estrogen drops and the fat storage increases. 

So, estrogen acts as a direct inhibitor of lipoprotein lipase. So, when estrogen levels drop, lipoprotein lipase kicks up.

As we progress in the article, you're going to see how estrogen's effects stack on top of each other to synergistically impact fat storage and fat burn in positive ways, as do the consequences of low estrogen...

Let's move on to the next key player in our female fat loss saga...

Estrogen Increases Insulin Sensitivity & Protects Against Insulin Resistance

Estrogen optimizes insulin production and insulin sensitivity. There is no doubt that after menopause, women face all kinds of metabolic clues that demonstrate just how important estrogen is to insulin and insulin sensitivity. 

After menopause, many women suffer from high cholesterol and triglycerides, increased central obesity, and clear insulin resistance...all hallmarks of metabolic syndrome. (Endocrine Reviews, vol. 34) 

These effects seem to be directly tied to estrogen receptors because when we genetically modify mice so that they do not express estrogen alpha receptors they demonstrate high blood sugar, high leptin, high insulin levels, and they burn fewer calories and become naturally more sedentary!  (Diabetologia, vol. 49)

These effects have been confirmed in humans in studies on men and women with low estrogen due to genetic defects that cause insufficient estrogen production. These low-estrogen individuals show signs of insulin resistance and high insulin, which is reversed with estrogen supplementation. (Journal of Clinical Endocrinology and Metabolism)

The bottom line is estrogen has dramatic effects on insulin sensitivity. The more insulin sensitive the lean tissues of the body, the less fat you will generally store! The lower your estrogen levels drop, the more insulin resistant your body will become.

This point will become vitally important when we discuss how to reverse this effect as estrogen levels drop after the age of 30, reach a tipping point around 40, and then a critical point in menopause. 

Estrogen Increases Your Body's Fat Burning/Anti-Aging Hormone

Within the body is a POWERFUL hormone called growth hormone. Growth hormone is considered one of the body's most important anti-aging hormones because it triggers repair and rejuvenation of tissues throughout the body. 

Beyond the powerful and welcome anti-aging benefits, growth hormone is also one of your body's most powerful fat-burning hormones. 

Sadly, as we age, growth hormone levels naturally drop and the effects of low growth hormone are exaggerated by low-estrogen.

It turns out that without sufficient levels of estrogen, your body does not respond as well to growth hormone. This demonstrates how we can't view the effects of hormones individually...think of your hormones more like a web of interconnected effects and actions. When you pluck one string of the web, it reverberates across the whole web...

Change one hormone and you either directly or indirectly change other hormones.

Estrogen appears to work by stimulating growth hormone receptors (the effect) and may also influence the production of growth hormone (the amount).

Interestingly, in post-menopausal women, when estrogen is given orally, the growth hormone levels drop resulting in more weight gain and less fat burning. When estrogen is given transdermally,  through a patch or cream, estrogen actually benefits the growth hormone pathway leading to fat loss. (Pituitary Today: Molecular, Physiological and Clinical Aspects)

Ugh! Why do you hormones have to be so complicated? 

This oral estrogen effect partially explains why so many women struggle with weight from oral contraceptive use...when all of that estrogen hits the liver it negatively impacts growth hormone production and signaling! The result is less fat burning! 

As estrogen levels drop, you get the side-effect of insulin resistance (which we already discussed) this then increases insulin production and high insulin suppresses...you guessed it...growth hormone. 

For our post-menopausal readers, one of the most common complaints associated with menopause is sleep disturbances. Guess when your body produces the most growth hormone? You guessed it, while you sleep!   So, as sleep gets disturbed, growth hormone problems worsen. So that's a triple whammy!

To review...when estrogen levels are naturally high (as in youth) it appears to enhance the effects of growth hormone resulting in more fat burn and faster recovery of tissues.

When estrogen is supplemented in tablet or capsule, it likely has a NEGATIVE effect on growth hormone resulting in less fat being burned. When estrogen is supplemented via cream or patch, it may improve growth hormone signaling and thus enhance fat burning. The growth hormone issues are further exacerbated by insulin resistance and poor sleep. 

Let's move on...

Introducing The Scourge Of Female Fat Loss

Within the fat cells you will find two important types of receptors that influence your ability to burn fat: alpha receptors and beta receptors. 

Beta receptors activate fat release while alpha receptors inhibit fat release. These receptors are both activated by the adrenal hormone epinephrine, also known as adrenaline. Think of the beta receptors as the gas peddle of fat loss and the alpha receptors as the brake peddle of fat loss. 

Here's where things get depressing...

Women have 9X more alpha receptor than beta receptor activity in "stubborn" fat found in the hips, thighs, and butt. Sadly, generally speaking, women also have more alpha receptors than men if we take into account all fat in the body. 

Estrogen, it turns out, impacts the activity of alpha receptors in a good way. Higher estrogen found in youth seems to add more gas peddles and fewer brakes to the fat cell. The result is estrogen allows you to burn more fat due to less alpha receptor activity. 

This also explains why some women store more in the hips, thighs, and butt...they simply have more alpha receptor activity in these regions (genetically determined) than women without these "problem areas" (if there is such a thing as a "problem" area). 

When women's estrogen levels drop, alpha activity kicks up. The result is less fat burn in these tissues. Don't worry, later in the article, we'll talk about how to tone down alpha activity and kick up beta activity...

This alpha receptor issue also partially explains why a starvation diet is the wrong approach and why it's even more damaging to women with low estrogen, such as those in menopause (or even those who are over 40).

For now, just know that as a woman you have higher alpha receptor activity...especially in problem areas like the thighs, butt, and hips. We'll discuss the antidote later. 

Now that we know about alpha and beta receptors, we can move on to the next player...

Estrogen Increases Epinephrine (Adrenaline)

Epinephrine is a hormone released by the adrenal gland. You may know it as "adrenaline". 

When released by the body for short periods of time, adrenaline stimulates fat burning by activating the beta receptors. We'll discuss how to simulate adrenaline release in the right amounts later in the article...

Adrenaline activates beta receptor, but also activates alpha receptors. This explains why you lose weight in your face before you lose weight in your problem areas. Alpha receptors, which we learned are found in up to 9X more quantities in stubborn female fat, inhibit fat loss in these areas. 

So, when estrogen levels are healthy, your body kicks up fat burn by kicking up adrenaline production (and by buffering alpha receptor activity). This effect also explains why post-menopausal women don't seem to lose as much weight with exercise, especially cardio. The exercise doesn't trigger the same level of adrenaline it did in the younger years, add to that the enhanced alpha receptor activity triggered by low estrogen and you get a double whammy of fat storage. 

For now, just know that there is a way of eating, exercising, and living that can optimize both adrenaline production and adrenaline response in the female fat cell! This "way of living" can be effective for women under 40 and women over 40, including post-menopausal women. More to come...

The next key player is blood flow...

In order to burn fat you must release it into circulation from fat cells so that it can be delivered to the lean tissue to burned for energy. To achieve this, tiny blood vessels called capillaries perfuse throughout the fat. 

One effect of adrenaline is to increase in blood flow by stimulating the heart to beat faster and stronger while influencing the blood vessels. Estrogen also appears to influence blood flow to the tissues, such as fat. As estrogen levels drop, your body doesn't deliver as much blood flow to the fat cell. This can interfere with your ability to release fat into circulation, especially around the stubborn areas! 

I'm not going to spend too much time on this one, I just wanted to bring it to your attention. When we get into the discussion on exercise, many of the recommendations we make will enhance blood flow to your fat cells!

Estrogen Makes The Body A Fat-Burning Machine

When estrogen levels are higher, the body fuels itself off of more fat than sugar. As estrogen levels drop, your body starts burning more sugar and less fat. 

This is just one more reason why the over-forty metabolism allows for less fat burn. Here's the problem...

None of the effects of estrogen deficiency exist in a vacuum...they compound and act synergistically...

When you have a body that has more difficulty burning fat (as in the estrogen deficient body), it starts to burn sugar, this is then compounded by the insulin resistance that occurs with low estrogen. The result is wild swings in blood sugar that then trigger cravings and hunger. The cravings and hunger that ensue leads to the over-forty appetite that ultimately leads to more calories and more fat storage. 

That's not all...there's more...

Wait, wait, wait, I know this is all sounding like a depressing situation. I promise, I'm not going to leave you hanging! I must lay problems at your feet so that the solutions will make sense later! 

Now let's get into one of my FAVORITE topics...mitochondria. 

Mitochondria: The Bottleneck Of Aging And Metabolism

I am obsessed with mitochondria, and for good reason...

Mitochondria are the bottleneck of aging. They are also the key to age reversal...you heard me right, understanding how mitochondria function can help you to turn back the clock and actually help make your cells grow YOUNGER! So much so that I will be spending much of this year writing on ways to rejuvenate your mitochondria. (This alone is worth signing up for our newsletter and podcast to get this groundbreaking information. You won't want to miss this)

In THIS article we're going to talk high-level, just touching the surface of what mitochondria are and how they impact your health and metabolism, and then we'll get into the influence of estrogen on mitochondria. 

First off, mitochondria are the powerhouse of your cells. They manufacture the majority of the energy that fuels your body, and when they become dysfunctional it leads to a dramatic drop in energy, and a dramatic rise in risk of many, MANY chronic diseases associated with aging. 

When mitochondria reach a critical state of dysfunction, they trigger your cells to commit cell suicide, which biologists call "autophagy" (to eat oneself).

When we nurture, protect, and feed our mitochondria we are rewarded with boundless energy, youthful vitality, and resistance to diseases such as heart disease, cancer, diabetes, arthritis, osteoporosis, muscle loss, and premature wrinkling ...just to name a few.

For our discussion today, just know that "when your mitochondria don't work, your metabolism don't work". Also, estrogen helps to stimulate repair of existing mitochondria, the production of more energy in your current mitochondria, and even stimulates your body to make NEW mitochondria. 

This can explain why so many menopausal women report plummeting energy levels, decreased exercise performance, muscle weakness, decreased recovery from exercise, generalized fatigue, tiredness, and poor immune function. 

Mitochondrial dysfunction explains it all!

Estrogen appears to impact the health and function of the mitochondria from multiple pathways. When estrogen levels are optimal, your mitochondria will be healthier as a result. 

There is far more to this story, in fact, there are many other factors that will determine how healthy your mitochondria are and how energetic your cells will be, but we'll have to shelve that discussion for another time. Just know that many of the recommendations to come, will improve a woman's ability to burn fat at least, in part, due to its beneficial effects on mitochondrial function and health. 

Certainly, a low-estrogen situation certainly does cause a hurdle to healthy mitochondria, but not an insurmountable challenge as we'll discuss later. On to the next...

Cortisol: The Enemy Of Female Fat Cells, The BFF of Belly Fat

No one would challenge me on the statement that a high cortisol level for extended periods of time is BAD for your weight loss aspirations. Well, this next discussion might shine some light on why belly fat becomes such an issue for the over-forty metabolism...

Estrogen and progesterone both help to antagonize cortisol. So, in our youthful years, when estrogen levels are high, the effect of cortisol on fat is less problematic because estrogen and progesterone counteract the negative effects of high cortisol. 

This explains why belly fat is fairly uncommon in women before the age of 40. (I know, some of you are saying, I've been dealing with belly fat since my twenties...I'll get to you in a minute)

As estrogen and progesterone levels drop and reach a critical level after menopause, the perfect storm of belly fat occurs...high cortisol AND high insulin.

Think about it...estrogen and progesterone are no longer around to counteract the fattening effects of cortisol and the low-hormone environment along with dysfunctional mitochondria leads to insulin resistance and thus high insulin. The end result is BELLY FAT!

That's just scratching the surface, add sleep disturbances, loss of muscle mass, poor energy, carb cravings, and hunger to the mix and bye-bye flat stomach, hello belly fat...

Estrogen and progesterone isn't the entire picture. You can stress yourself into oblivion, even at a younger age when estrogen and progesterone levels are high, and overwhelm the cortisol-buffering effects of these hormones...which explains why some of you have dealt with belly fat since youth, you were relentlessly stressed out. True or true? 

The take-home message here is "high cortisol = bad", at least when it's elevated for extended periods of time. Add high-insulin to high-cortisol and you have the recipe for belly fat. Add a low-estrogen and the rest is history.

Men do not enjoy the cortisol-buffering effect of estrogen and that at least partially explains their susceptibility to belly fat even at younger ages. 

Aside from all of the factors that we have already discussed, there are other benefits of optimal estrogen, which means that there are more problems for women over 40 whose estrogen levels may not be quite "optimal".

Estrogen Leads To More Spontaneous Movement

First, estrogen seems to increase non-exercise activity thermogenesis (NEAT). NEAT is all activity that happens outside of working out. This can be fidgeting, spontaneous activity like having the sudden urge to get up from a chair and move, it can be taking out the trash, etc. When estrogen levels are optimal, you just want to move more through spontaneous NEAT. 

When estrogen levels drop, your innate motivation to move is replaced by an innate desire to imitate a sloth. NEAT is a significant contributor to fat burn and may negatively impact your ability to burn fat as estrogen levels drop. 

Estrogen Speeds Recovery From Exercise & Injury

Estrogen levels help you repair and recover after exercise or injury. This means that "after-forty you" will not rebound from exercise as quickly, after menopause you may be sore for more than a week. Luckily, there are ways to improve our recovery and repair, which we'll cover later...

Estrogen Decreases Appetite

Estrogen helps to keep your appetite in check, likely through its influence on hormones like leptin and ghrelin.

As estrogen drops you will naturally crave more, snack more, and eat more. This will require more diligence with our diet in order to assure that we're not overeating. 

Estrogen As A Fat Loss Hormone Review

I know it's strange to think of estrogen as a hormone that impacts your ability to burn fat, but hopefully by now you've had a bunch of "ah ha's!" 

To review...

1. Estrogen inhibits lipoprotein lipase (less fat storage)
2. Estrogen increases growth hormone (more fat burning)
3. Estrogen increases epinephrine (more fat burning)
4. Estrogen inhibits insulin production (Less Fat Storage)
5. Estrogen Increases Insulin Sensitivity (Less Fat Storage)
6. Estrogen increase blood flow to fat cells (More Fat Release)
7. Estrogen causes more fat to be burned over glucose (More Fat Burning)
8. Estrogen optimizes mitochondrial function (More energy)
9. Estrogen influences the hunger centers of the hypothalamus (Less hunger)
10. Estrogen may influence non-exercise thermogenesis (NEAT) (More Calorie Burn)
11. Estrogen speeds recovery from exercise and decreases muscle soreness (Less Pain)
12. Estrogen decreases inflammation and muscle damage post workout
13. Estrogen works with progesterone to counteract high cortisol (Less fat storage) 
14. Estrogen helps to optimize leptin and ghrelin (less appetite and more fat burn)

Now that we've uncovered many ways in which estrogen can impact weight loss, let's look at some other ways a woman's metabolism differs from that of a man...

Women Burn More Fat At Low Intensities Of Activity

All too often, women believe that men are better at burning fat, but that would be inaccurate. Women are actually better fat burners than men...the problem is, they are also better "fat storers" as well and most of us have a fat storing problem more than we have a fat burning problem. 

In fact, at 90 minutes of walking women are burning 79% of their calories from fat while men are burning just 59% of their calories from fat. ( Journal of Applied Physiology, 85(5))

This moves walking up the list of priorities for a female fat loss workout program.

My goal isn't to say that walking is sufficient to overcome the female fat loss resistance experience by many women, it's to say that walking is a vitally important component of a fat loss program for men and women...doubly so for women...triply so for post-menopausal women. 

Sadly, walking has fallen out of vogue. That is unfortunate, because walking is one of the few forms of physical activity that doesn't activate compensatory eating and compensatory slothfulness...which is the next topic.

Also, walking is RESTORATIVE, it actually resets the nervous system and lowers cortisol, which we already discussed is quite problematic for estrogen-deficient women.

Now let's talk about the "compensatory engine"...

Women Compensate For Calorie Deficits More Than Men

At Cut The Fat Podcast we often talk about the "Compensatory Engine"...

In a nutshell, when we eat less and exercise more we often activate an unconscious drive to eat more and move less. We call this "compensatory eating" and "compensatory slothfulness", together they make up the "compensatory engine".

The larger the calorie deficit the more aggressive your hunger and cravings will be and the more tired you will feel. 

This is important because to be successful with lasting weight loss, we need to learn NOT to activate our compensatory engine as this system is designed to keep up from burning fat. This is what is responsible for the yoyo effect we experience when we lose weight and gain it back repeatedly. 

Women are already more susceptible to the compensatory engine and as estrogen levels drop, that susceptibility skyrockets!

This means, generally speaking, smaller calorie deficits trump larger calorie deficits when lasting weight loss is the goal. One reason why long bouts of cardio (i.e. jogging, cycling, rowing, etc.) fail us is because they burn so many calories that the compensatory engine is kicked into overdrive and our appetite, cravings, and desire to sit on a couch go into overdrive. 

This also explains why walking is such a crucial part of a complete female fat loss workout program...walking burns calories WITHOUT activating the compensatory engine.

Said another way for effect...Jogging, running, cycling, rowing, aerobics, etc. burns more calories and almost ALWAYS activate the compensatory mechanisms that keep us fat...

As we'll learn later, the best forms of exercise for women, especially women over forty, are walking, resistance training, and H.I.I.T., we'll talk more about this soon. 

Now that we've covered some key influences of estrogen, and lack thereof, on female fat loss, we're going to start journeying into the realm of what to do, starting with the Female Fat Loss Diet Program. If you're ready, click the link below to continue to Part II...

Part II: The Female Fat Loss Diet Program >>

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References: 

1. Estrogen Suppresses Transcription of Lipoprotein Lipase Gene. J Biol Chem. 2000 Apr 14;275(15):11404-11.
2. F. Mauvais-Jarvis, D. J. Clegg, and A. L. Hevener, “The role of estrogens in control of energy balance and glucose homeostasis,” Endocrine Reviews, vol. 34, no. 3, pp. 309–338, 2013.
3. G. Bryzgalova, H. Gao, B. Ahren et al., “Evidence that oestrogen receptor-α plays an important role in the regulation of glucose homeostasis in mice: insulin sensitivity in the liver,” Diabetologia, vol. 49, no. 3, pp. 588–597, 2006.
4. L. Maffei, Y. Murata, V. Rochira et al., “Dysmetabolic syndrome in a man with a novel mutation of the aromatase gene: effects of testosterone, alendronate, and estradiol treatment,” Journal of Clinical Endocrinology and Metabolism, vol. 89, no. 1, pp. 61–70, 2004.
5. Arzt E, Bronstein M, Guitelman M (eds): Regulating of Growth Hormone Sensitivity by Sex Steroids: Implications for Therapy Pituitary Today: Molecular, Physiological and Clinical Aspects. Front Horm Res. Basel, Karger, 2006, vol 35, pp 115-128
6. Horton, TJ, Pagliassotti, MJ, Hobs, K, Hill JO. 1998. Fuel metabolism in men and women during and after long-duration exercise. Journal of Applied Physiology, 85(5), 1823-1832 
7. Anisha A. Gupte, Henry J. Pownall, and Dale J. Hamilton, “Estrogen: An Emerging Regulator of Insulin Action and Mitochondrial Function,” Journal of Diabetes Research, vol. 2015, Article ID 916585, 9 pages, 2015.