Body composition regulation has a very complex relationship between fat, hydration, muscle, and bone mass. Female hormonal regulation is in fact regulated in the brain with the hormones of GNRH, LH, FSH.
These regulatory hormones that control hormones in are integrally linked and seem to control how we gain or lose weight, how the weight is distributed, how fit we are, how much muscle we can build as we get older and many other aspects of our health. Evaluating your hormone levels can be an important part of managing your fitness as well as your mood and your hormonal symptoms.
Measuring the key hormones should be done at various check points during the day and month, not just one time. This is why saliva testing can help get you a more comprehensive picture of your hormones.
To understand the complex relationships between the hormones and how fit you are is more accurately measured by body composition readings than BMI. Specifically knowing your relative skeletal muscle mass can determine if you have an appropriate amount of strength for your gender and age. Knowing your body fat, and the differential between your visceral fat (deep) and your overall fat percentage can determine your overall leanness.
Hot flashes are related to brain hormone surges and thermoregulation. It is important to be lean for thermoregulation. Once it was thought that heavier women would have fewer hot flashes because of overall higher estrogen levels. Then the prevalent theories were that body fat functions as a natural 'sweater layer, and it was postulated that women with increased Body Fat Percentages had more hot flashes.
In a new study published in Nature in May of 2017 Mone Zaidi and colleagues tested the theory of FSH, a brain hormone that is involved in the regulation of ovulation in younger females, can be involved in how the body begins to accumulate more deep fat deposits as a person ages. The researcher gave an antibody to bind and lower pituitary hormone FSH (follicle-stimulating hormone). In animal models reducing FSH reduced overall adipose tissue and fatness. Reducing FSH in animal models gave healthier bones as well. Reducing FSH improved leanness even in those animals fed a high-fat diet, in part due to increased metabolism and oxygen consumption. It is thought this can both help explain some of the complex relationships between fat and the cascade of brain hormones that are responsible for our body composition.
Hormone therapy can reduce FSH, and this may explain why hormone therapy helps keep many women more lean.
Fat is our largest endocrine organ, some hormones in our fat are converted to estrogens. The amount of hormone produced by the fat is relatively small, and the hormones produced are weak. But being obese may offset some of the benefits on metabolism and brain chemistry others can get from hormone use.
Individual consultation, knowing the type of die you have, your lifetime exposure to hormones, and other factors such as genetics can help determine what might help you the most when it comes to helping yourself have the healthiest brain chemistry and the leanest body.