Nearly all significant studies in the field of human nutrition and exercise were done exclusively with male subjects. It's only very recently that women have been included in these studies, let alone the focus of them. Without significant data on how women experiece and are affected by training and nutrition, it is not uncommon for women to experience adverse consequence when following dietary amd fitness programs designed for men.
Hormones and the Female Metabolism
Let’s start with a Summary:
Men and women have the same hormones, but they have them in different quantities/ratios compared to each other. This difference causes women to not only store more fat and store it more easily, but to also store it in very specific areas, like the breast, hips, and thighs.
Fluctuations in female hormonal levels are affected by menstrual cycles, age, lifestyle, and the environment.
Genes affect metabolism somewhat, but there are four other core factors that truly affect female weight loss.
Weight loss resistance (aka “metabolic adaptation”) can develop from chronic dieting and extreme calorie deficits.
There are some soolutions to reversing the effects of metabolic down-regulation:
A doctor can run tests that will verify whether or not you do have a hormonal imbalance.
Weight training, not cardio, is critical for fat loss.
Take the right kinds of supplements, not some gimmicky pill marketed to “block carbs” or “burn fat” or that is promoted by Dr. Oz as a “miracle drug” like green coffee bean extract. Ugh.
Eat organic, whole, and unprocessed foods more often than not.
Men and women have the same hormones, but they have them in different quantities compared to each other. This difference cause women to not only store more fat, but store it in specific places, like the breast, hips, and thighs. The key players in the hormonal difference between men and women are testosterone, estrogen and progesterone. In women: it’s estrogen that causes more fat to be stored in the hips and thighs, and it’s both estrogen and progesterone that cause fat to be stored in the breasts. In men: it’s testosterone that causes most of their fat to store around the mid-section; however, testosterone is also a key player in fat burning. Other hormones that are responsible for fat storage are: excess cortisol (tummy), excess insulin (“love handles”), decreased testosterone (arms), decreased thyroid (armpit area), and human growth hormone (calves and ankles). This concept is known as “Body Fat Signature” or “Biosignature” fat storage. Hormonal treatments during such procedures as gender reassignment, for example, demonstrate how this is true. Males transitioning to females will begin to gain fat in the hips and thighs once undergoing hormone replacement therapy that includes estrogen. Fluctuations in female hormonal levels are affected by menstrual cycles, age, lifestyle, and the environment. In a nutshell, and without getting too technical, when females are in the follicular phase of their menstrual cycles (when the egg follicle is maturing), estrogen levels are higher than progesterone. This lower relative-progesterone level is what causes PMS symptoms like bloating, moodiness, fatigue, and cravings. Women who have extended estrogen dominance will tend to have bigger hips and thighs. While females are in their luteal phase (after the egg is released from the ovary), progesterone levels are higher than estrogen. Women who have a higher ratio of progesterone than estrogen tend to have larger breasts and smaller hips and thighs. Those bitches. (JUST kidding!!!) But in general, women tend to be estrogen dominant and that’s why the hips and legs are often the last area from which we lose fat. That doesn’t mean that estrogen is “bad” - it aids in the body’s insulin sensitivity and it has muscle building and fat burning benefits in that regard – its levels just need to be in balance.
And when in our lives are we especially estrogen dominant? When do we make more estrogen at one time than we do the rest of our entire lives combined? Wel, during pregnancy, of course! We are primed to store fat while pregnant. And this is a GOOD thing. It's good for the baby, and it's good for making breastmilk. We remain estrogen dominant for several months after birth, which is just one reason why it can be difficult to lose fat early in our postpartum recovery.
On the other end of the spectrum, PCOS is a too-common condition in women that causes elevated testosterone and insulin levels, which can lead to weight gain, infertility, and the development of “male traits” such as fat storage in the torso, facial hair, acne, and hair loss along the hairline. When it comes to age, lifestyle, and environment, the common denominator for a lot of women that includes all three of these is the build-up of the effect of constant low-calorie diets coupled with excessive aerobic exercise over years and years that eventually catches up with women later in age. Additional factors include things from our environment that mimic estrogen in our bodies and cause our bodies to respond as if there is estrogen dominance. These “things” in our environment include fire retardants, PFC’s in nonstick cookware, mercury, and plastics leaching into our food and water (including BPA and BPA-free). Many of these mimic thyroid hormones in our body, as well, and are absorbed by our thyroid gland, which is then unable to release these toxins. As a result, our immune system may attack the thyroid, leading to Hashitmoto’s Disease, one of the leading causes of hypothyroidism and affecting 7-8% of the population. Genes affect metabolism somewhat, but there are several core factors that truly affect female weight loss. As mentioned, hormonal imbalance is just one. Others include:
Adrenal imbalance caused by stress demands on our adrenal system from excessive exercise, lack of sleep, stress at work, and stress at home. (aka "life after baby")
Neurotransmitter imbalance in the hypothalamus and/or pituitary gland that is preventing the brain from signaling the proper hormones that control hunger levels, thyroid function, or hormone absorption and conversion.
Digestive imbalances in either the form of poor nutritional choices, nutrient deficiencies, or disrupted gut flora from use of antibiotics, illness, or poor dietary habits.
So how can women fix this problem? If you have any reason to suspect that you may be suffering from any of these four factors, it will be best to work with a functional medical practitioner (i.e. endocrinologist) specializing in an integrative approach to restoring the balance to your hormones, adrenals, and digestion. A doctor will be able to order the appropriate tests to diagnostically evaluate how your cortisol levels, sex hormone levels, thyroid levels, vitamin and mineral levels, and assess any digestive issues or food intolerances you may be suffering from. I, myself, work closely with an M.D. that specializes in integrative and holistic healthcare and have undergone extensive testing for all of the above. She was able to come up with both natural and synthetic solutions to optimize my metabolism and overall well-being. If this kind of care is not accessible, there are definitely steps that you can take yourself to try to correct any of the above. Here is what I recommend from my non-medical standpoint:
Add a weight training regimen to your workout program. Weight training allows for muscle growth, and increased muscle growth promotes HGH and DHEA production – both of which promote fat burning and block fat storage in the stomach area. Lifting weights also increases bone density and overall strength and self-esteem. Additionally, muscle (unlike fat) is more thermogenic and burns more calories per pound. “Cardio” is still important for heart health and endurance, but don’t let it replace weight training.
Decrease exposure to estrogen-mimickers.
Supplement properly with Vitamin D, high quality fish oils, calcium, folate, etc. (Clients: please see the supplement guide provided to you at the beginning of our program for specific details).
Make sure you are eating enough fiber from fruits, vegetables, and whole grains. Most people don’t get the recommended daily value (25g for women, 38g for men) and studies have shown that premenopausal women that increased their fiber intake by 15g per day were able to reduce their estrogen levels significantly.
Make sure you are eating the right balance of protein to carbs to fat. When people seek out “low carb diets” and “have success” with them, they don’t realize that the initial dramatic loss in weight is simply from water depletion. Calorie-for-calorie (when protein is controlled for), low-carb diets do not "burn" more fat than high-carb diets. Moderation is key. Fats and Carbs both have their place in a diet. Focus on nutrient-dense sources of both, and you will avoid many of the self-imposed hurdles that cause over-eating.
Get more sleep. I know it’s easier said than done. But limit the amount of time you spend in front of digital devices before you go to sleep. The light from our computers, TVs, smartphones, and tablets mess with the melatonin in our brains and disrupt our quality of sleep. Adequate sleep is essential for fat loss.
STOP WITH THE CRASH DIETS AND LOW CALORIE DIETS!!!! This may work for a short period of time, but it’s unlikely that you will be able to sustain it happily. And in the long run, it will lead to an excess of ghrelin (hunger hormone) and cortisol (belly fat hormone), and a deficiency in leptin (satiety hormone) or leptin resistance as our bodies begin to disregard leptin signals and thinks our bodies are starving, even though there is a lot of fat. It is nearly impossible to resist the power of these hormones in our body convincing us that we MUST EAT! Work with an experienced coach that can help you to safely reverse diet out of a low calorie diet history. You don't have to starve yourself to achieve weight loss. Restrictive diets are no way to live life!
This is a lot of information in a very condensed form. I encourage you to ask any questions and to speak to your medical provider or nutritionist/dietician if you think any of these issues impact you. It is very frustrating knowing that there can be so much working against us in trying to lose weight after struggling for so long, but once you get familiar with the proactive changes that you can make, then you will see HUGE improvements in your health and well-being.