Understanding Your Hormones

Oestrogen; progesterone; testosterone; and cortisol get blamed for a great deal, and much of what's said about them online isn't accurate. In this video, I'll explain where these hormones come from, what they actually do and what a blood test can and cannot tell you. All four of these hormones are made from cholesterol; along the same production line in the body. That means oestrogen and testosterone aren't really opposites, because testosterone is the raw material the body uses to make oestrogen. There are three different types of oestrogen, and they don't all behave the same way. Oestradiol is the strongest, made mainly by the ovaries before the menopause; while oestriol matters mostly in pregnancy. After the menopause, a weaker form called oestrone takes over; made mostly in fat tissue, so body weight has more influence on oestrogen levels. Across a monthly cycle, these hormones rise and fall in a set pattern. Oestradiol climbs in the first half; progesterone rises after an egg is released; and if there's no pregnancy both fall and a period starts. A cycle anywhere from 21 to 35 days long is normal; and 28 days is simply the average. Women make testosterone too, in the ovaries and the adrenal glands. Many people assume it drops sharply at the menopause, but studies following the same women over time suggest it doesn't. Instead, it falls gradually with age, while having the ovaries removed surgically does cause a sudden drop. You may hear testosterone offered as a treatment, but it has only one evidence-based use in women; which is low sexual desire causing distress after the menopause, following a proper assessment. Trials haven't shown that it helps mood, energy or memory. In the context of a hormone-sensitive breast cancer diagnosis; testosterone treatment isn't recommended, and exceptions are only rarely made when nothing else has helped. The fourth hormone, cortisol, is often called the stress hormone; but it mainly follows your body clock, peaking in the early morning and lowest late at night. So a cortisol result means very little without knowing what time it was taken, and it doesn't measure how stressed you feel. That doesn’t mean cortisol never matters, because persistently high cortisol can do real harm, such as weight gain around the middle and thinning bones. That comes from long-term steroid medicines, or a rare condition called Cushing's syndrome, rather than from the ordinary stresses of everyday life. Timing and context matter for every hormone test, which is why blood tests are most useful for answering specific questions. These include whether you’re ovulating; how your thyroid is working; or whether you have polycystic ovary syndrome. In women under 45, a test for a hormone called FSH can help support a diagnosis of early menopause. Over the age of 45, though; national guidance is that menopause is diagnosed from your symptoms rather than from blood tests. Hormone levels swing widely from week to week at this stage, so a single result can easily point in the wrong direction. Timing can trip up other tests too, such as progesterone, which is often checked on day 21 of the cycle. That’s only right in a 28-day cycle; so in a longer one the result can look falsely low and wrongly suggest a deficiency. These pitfalls are one reason to be wary of hormone balancing; saliva testing and adrenal fatigue, which are widely promoted but not supported by the evidence. There’s no agreed definition of a hormone imbalance, and no reliable test for one. Hormones are meant to rise and fall, and that natural variation is how they work. Adrenal fatigue in particular, isn't a recognised medical condition, and blaming exhaustion on it can delay finding a treatable cause; such as thyroid disease, anaemia or depression. There's also no good evidence that stress causes breast cancer; and I'd rather say that plainly than leave you wondering. For more information, please review our booklet which goes into each of these hormones in more depth. If you have questions about your own hormones or test results, please get in touch with me or my team.