3 Needs context
Excessively high estradiol levels suppress lipolysis and promote insulin resistance and energy storage.
"And then if you take too much estradiol, it starts to promote energy storage and we get back to insulin resistance. So it's like this U-shaped curve on a graph. There's like we don't want to be over here, we don't want to be over here. And we get this rising insulin tone, it suppresses lipolysis, which is the breakdown of fat." (said at 0:34:50)
Physiological estradiol generally enhances insulin sensitivity, protects against metabolic dysfunction, and supports lipid homeostasis. However, evidence from cellular models supports a biphasic (inverted U-shaped) dose-response curve, where low/physiological estradiol concentrations stimulate insulin signaling and glucose transport, whereas supraphysiological/excessive concentrations impair insulin receptor substrate-1 (IRS-1) phosphorylation, inducing insulin resistance and favoring lipid storage. Insulin itself is the primary anti-lipolytic hormone that suppresses lipolysis in adipose tissue. While this mechanism is well-documented in vitro, robust clinical trial evidence demonstrating that clinical estradiol overdose causes insulin resistance and lipolytic suppression in humans remains limited.
Excessively high estradiol levels can disrupt thyroid binding sites, impair cortisol signaling, and stimulate autoimmune disease, while progesterone protects against autoimmune disease.
"too high of estradiol can mess up thyroid site binding. Too high of estradiol can mess up cortisol signaling. Too high of estradiol can drive autoimmune disease. The very simplistic version of that is progesterone protects against autoimmune disease and estrogen may drive it." (said at 0:41:30)
The statement captures broad endocrine and immunomodulatory concepts but oversimplifies complex mechanisms. Elevated estrogens (particularly oral formulations via hepatic first-pass metabolism) stimulate the hepatic synthesis of thyroxine-binding globulin (TBG) and cortisol-binding globulin (CBG), altering total and free circulating thyroid and cortisol hormone levels rather than damaging cellular binding sites or receptor signaling. In immunology, estrogen exerts nuanced, dose- and context-dependent biphasic effects: while it can enhance B-cell activation and humoral immunity (frequently exacerbating antibody-mediated diseases like systemic lupus erythematosus), it can also suppress cell-mediated inflammation and improve conditions like rheumatoid arthritis. Progesterone generally exerts immunosuppressive effects, but neither hormone functions simply as a universal driver or protector against all autoimmune diseases.
- context: A randomized, open-label, crossover study comparing the effects of oral versus transdermal… (Menopause (New York, N.Y.) 2007) · cited 87x in the literature
"The mean (SD) percentage changes of thyroxine-binding globulin, total T4, and free T4 with oral CEE were +39.9% (20.1%), +28.4% (29.2%), and -10.4% (22.3%), respectively, versus +0.4% (11.1%), -0.7% (16.5%), and +0.2% (26.6%) with TD E2. The mean (SD) percentage changes of cortisol-binding globulin, total C, and free C with oral CEE were +18.0% (19.5%), +29.2% (46.3%), and +50.4% (126.5%), respectively" (abstract, results, passage verified)
pubmedfull study (doi) - context: Estrogen, progesterone, and testosterone: can they be used to treat autoimmune diseases? (Cleveland Clinic journal of medicine 1994) · cited 91x in the literature
"Progesterone and androgens suppress the immune system, prolactin stimulates it, and estrogens can do either. Rheumatoid arthritis tends to improve during pregnancy, during estrogen replacement therapy, and during treatment with estrogen-containing oral contraceptives. Systemic lupus erythematosus is aggravated by pregnancy and probably by estrogens." (abstract, results, passage verified)
pubmedfull study (doi)
Progesterone induces hyperinsulinemia, acts on the pancreas and liver, and antagonizes GLUT4 receptor translocation in skeletal muscle to deposit body fat.
"progesterone has important effects on carbohydrate, lipid, and protein metabolism. Um it induces this sort of roundabout hyperinsulinemia, which is increased insulin. It has some direct action on our pancreas and our liver. Um but and it has this antagonizing effect on our muscle getting that GLUT4 receptor up to bring in the the glucose. But basically just understand that its job is to deposit body fat so that we can have a baby." (said at 0:54:45)
Preclinical and animal studies show that progesterone and progestins can impair insulin sensitivity, reduce skeletal muscle GLUT4 protein content, and contribute to pregnancy-associated metabolic shifts that favor maternal adipose deposition. For example, in ovariectomized rats, progesterone treatment reduced skeletal muscle GLUT4 protein content by 21% and impaired exercise-induced glucose uptake, and progestin therapy in non-human primates significantly reduced skeletal muscle GLUT4 expression. However, framing progesterone's primary metabolic role simply as blocking GLUT4 translocation to deposit body fat oversimplifies complex endocrine interactions, and direct evidence demonstrating specific translocation antagonism in human skeletal muscle is limited compared to animal models.
Unverified means no publication matching the claim was located; it does not prove the claim false. Spotted an error? See the corrections policy - disputes from the people quoted are prioritized.