Estrogen is a key female sex hormone. There are three types of estrogens: estrone (E1), estradiol (E2), and estriol (E3). E1 is made by the body after menopause, while E3 is synthesized by the placenta during pregnancy. E2 is the most potent form and is the predominant one during reproductive years, mainly produced in the ovaries. Other parts of the body can also produce estrogens, like the adrenal glands and body fat (1).
The brain, specifically in the hypothalamus, is where the body regulates the energy that it spends and the one that it consumes (food intake), and therefore the body’s weight (2). Several hormones stimulate or inhibit neuronal pathways that take part in this food consumption/energy expenditure balance. Any disturbance or disequilibrium in this system would have an impact on our body weight. In the case of estrogens, it has been shown that they stimulate signals in the hypothalamus that decrease food intake and increase energy expenditure (2). Also, estrogens favor a subcutaneous (underneath your skin) body fat distribution instead of visceral fat (2). Visceral fat is the one that is accumulated in your organs, and it increases the risk of heart disease, diabetes, high cholesterol, and stroke (3). This is one of the reasons why in post-menopausal women, which experience a natural decline of estrogens, the subcutaneous fat redistributes to the organs. Apart from menopause, other conditions like PCOS, anorexia and excessive exercising can also affect estrogen levels (4).
What about men?
It seems like in men estrogens also have a role in regulating body weight, fat depot, and control of sugar levels in the blood (5). Testosterone can be converted to 17β-estradiol by an enzyme called aromatase. Studies in male mice showed that when this enzyme aromatase was inhibited, the mice were more obese and had more metabolic disturbances like fatty liver and insulin resistance compared to healthy mice. Interestingly, estradiol also influences mood and motivation in men, which indirectly affects appetite and physical activity, and therefore body weight. Lower levels of 17β-estradiol in serum were correlated to depressive symptoms in older men and men with obesity (5).
How to boost estrogen in your body?
A healthy lifestyle that includes enough sleep, moderate exercise, low stress, and healthy eating habits will have a positive effect on your hormones (6). Some foods, like flaxseeds, sesame seeds and soybeans, contain phytoestrogens, which are substances that mimic natural estrogen in the body. However, the real impact that phytoestrogens have on humans, considering the portion sizes that are consumed, is still under investigation (7). There are estrogen pills, creams, vaginal suppositories and shots. Ideally, always ask your doctor before using any of these products, first to make sure you have low levels of estrogens, but also because these types of products can increase the risk of blood clots, cardiovascular disease and stroke (7).
References:
1.https://my.clevelandclinic.org/health/body/22353-estrogen#:~:text=Estrogen%20is%20a%20sex%20hormone,that%20requires%20your%20provider's%20attention.
2.Fontana R, Della Torre S. The Deep Correlation between Energy Metabolism and Reproduction: A View on the Effects of Nutrition for Women Fertility. Nutrients. 2016 Feb 11;8(2):87. doi: 10.3390/nu8020087. PMID: 26875986; PMCID: PMC4772050.
3.https://www.webmd.com/diet/what-is-visceral-fat
4.https://www.healthline.com/health/estrogen-and-weight-gain#outlook
5.Rubinow KB. Estrogens and Body Weight Regulation in Men. Adv Exp Med Biol. 2017;1043:285-313. doi: 10.1007/978-3-319-70178-3_14. PMID: 29224100; PMCID: PMC5835337.
6.https://my.clevelandclinic.org/health/diseases/22354-low-estrogen
7.https://www.healthline.com/health/womens-health/how-to-increase-estrogen#if-natural-isnt-enough