If you’ve been experiencing issues with unexplained weight gain or difficulty with weight loss while using hormonal IUD, you’re not alone. Perhaps you’ve been made to question your suspicion about the link between the two from either articles you’ve read or conversations with your doctor. But if you believe that it’s not due to changes in your diet or activity level, hormone imbalance is the next place to look.
What’s important to understand is that there are two kinds of IUDs, hormonal and non-hormonal. The latter would be the copper IUD, which is the least likely to cause hormone disruption but can lead to copper toxicity for some women. But more commonly used IUDs are those like Mirena, Kyleena, and Liletta. All of which release synthetic progesterone (called Progestin) into your body as its means of pregnancy prevention. Though once thought to remain local to your reproductive organs, we now understand that our sex hormones are pushed systemically through our body, impacting gut, thyroid, as well as mental and metabolic health.
Most broad studies looking at weight gain while using birth control are flawed in the sense that they are looking at a wide collection of results across hundreds or thousands of women. Some reporting minimal weight gain (1-4lbs), some reporting high amounts of weight gain (>50lbs) and even some reporting weight loss. So when taking an average across a wide scope, we will often see results assuring us that weight gain is negligible and is more indicative of age and lifestyle rather than hormone birth control. This allows doctors and manufacturing companies to be dismissive when women become vocal about a significant increase in weight and body fat after starting use of hormone IUD.
What many women who feel a negative change within themselves are experiencing includes fluid retention, loss of muscle mass, depression, anxiety, low testosterone and libido, low thyroid hormone, estrogen dominance, and progestin replacing progesterone. These effects become more serious and long lasting the more time a woman has been on birth control.
It’s incredibly common to see women who started using hormone birth control (HBC) as a teenager or college student continue to use it over the following decades struggle harder with body composition and thyroid function as they get older. Hormone birth control may have been used to regulate their cycle early on, but since it doesn’t actually balance your reproductive hormones, the damage can be long lasting without conscious intervention with the goal of detoxing and supporting reproductive balance after discontinuing use.
Your progestin IUD may be causing your body to decrease production of your own natural progesterone levels. This is where the entire battle over weight gain really takes place. Your ovaries produce progesterone following ovulation, peaking in the luteal phase of your cycle. Ideally, our body holds a natural balance of progesterone and estrogen. Estrogen promotes storing healthy amounts of body fat, and progesterone inhibits estrogen receptors and helps the body metabolize that fat for energy. Estrogen helps our body retain salt and water while progesterone acts as a diuretic allowing water loss and decreased swelling.
Without adequate levels of natural progesterone, we become estrogen dominant. Both hormones can be low, actually, but if estrogen is still high relative to progesterone, you are estrogen dominant. We love estrogen when it’s in a healthy range, but too much leads to issues with PMS, increased bloating, mood instability, and excess body fat.
Both estrogen and progesterone, when out of balance will impair blood sugar regulation. We want decreased sensitivity to insulin during pregnancy for the sake of getting adequate nutrition to our baby, but we don’t want this all the time. Too much insulin circulating in the bloodstream can cause your body to convert more blood sugar into stored body fat. This also increases risks for PCOS.
Conversely, the synthetic estrogen in birth control pills can be up to ten times more potent than your natural estrogen hormones. Our fat cells are primed to receive that estrogen and encourage further fat accumulation. But the synthetic progesterone from birth control doesn’t have the attenuating effects against that supercharged fake estrogen.
Progesterone imbalance has an interesting impact on thyroid function. When progesterone is too low relative to estrogen, the body over-produces thyroid binding globulin. This protein prevents normal thyroid function. But what confuses many women is that when having blood work done, their thyroid hormones will read as normal. It’s the low progesterone preventing our body from actually using the hormone our thyroid is producing. Blood tests can only show you what is circulating in your bloodstream. They cannot show you what your body is adequately up-taking or detoxing.
Women who’ve shifted into estrogen dominance will also experience disruption in hunger cues as estrogen levels rise, the hunger hormone ghrelin, is sent in more limited amounts to the brain. But higher progesterone levels increase hunger cues. Women who are chronic under-eaters can struggle just as much with weight loss as women who are overweight due to over-eating. This is because over time, the metabolism downregulates to find homeostasis at lower calorie intake. Decreasing the number of calories your burn in your daily life and increasing your likelihood of gaining more weight should you suddenly start eating more than you have been.
Beyond HBC related metabolic down regulation, many women struggle with weight management because it’s directly linked to negative changes in mental health. A 2016 study done by the Journal of the American Medical Association looked at over a million women using progestin-only birth control (IUD) found high risk of depression and anxiety. Further studies show those using such birth control having triple the number of women being diagnosed with depression and using antidepressants compared to those who aren’t using birth control.
There’s enough evidence to show that HBC seems to alter brain chemistry, elevate inflammation markers, alter gut permeability, and deplete nutrients to such a degree that progestin is causing real harm systemically. The inflammation that HBC creates can promote insulin resistance, this leads to fatigue, weight gain and even diabetes.
We are not here to tell you what to do with your body as that’s a conversation between you and your trusted physician. You can remain on your preferred HBC method but you should be aware that it may well be impacting your health and physique goals negatively.
Ways to improve your experience include proper supplementation for hormone health including probiotics, GABBA, zinc (if using copper IUD especially), Baseline+ from Protea Nutrition, and vitamins C & E. Focus on a well-balanced whole foods diet high in antioxidants and fiber as well as a healthy exercise and sleep routine.