Understanding Hormones

Hormones, with their power to roll back the effects of ageing and boost sexual activity, have always been regarded with a mixture of fascination and alarm. In the first half of the last century, before testosterone or oestrogen were synthesised, there were lurid accounts of wealthy elderly males practising an adventurous and eye-watering form of anti-ageing medicine by grafting the crushed testicles of chimpanzees and other mammals onto their own which, they claimed, was hugely rejuvenating.

Much more concern and confusion now centres on HRT (hormone replacement therapy), which is composed of synthetic versions of the ‘female’ hormones, oestrogen and progesterone. The apparent panacea turned out to have a dark side, when HRT was found to actually raise the risk of heart disease and breast cancer following the large Women’s Health Initiative study in 2002.1 This has left millions of women in their forties and fifties in a dilemma. Do you plump for the benefits of HRT and hope to avoid the side effects? Or do you stay off it and hope to find something else? Official medical advice is that short-term use – two years – is not linked with an added risk. Even so, many have stopped taking it. In the wake of the 2002 study, the number of prescriptions in the UK and in the US has halved. In the years since there has also been a significant decline in the number of breast cancers.2

Natural vs Synthetic Hormones

There is a solution that is widely used in the US but little known in the UK. It involves the same hormones found in regular HRT but they come in a subtly different form known as ‘bio-identical’, which means that they are exactly the same as the ones your body was making until it reached the menopause, or the andropause in the case of men. The ones used in HRT are not identical, and this is very probably the reason for the problems they have caused; for example, a type of oestrogen still widely used (over 500,000 prescriptions were issued in England alone in 2010) is known as conjugated oestrogen and comes from the urine of pregnant mares, so it contains types of oestrogen normally only found in horses. The best-known brand is Premarin, and this was used in the Women’s Health Initiative trial.

The replacement for progesterone that is used in regular HRT is known as progestin (or progestagen), and the best-known brand is Provera. It also has a significantly different chemical structure from progesterone. This is linked to the very different effects the two have: progesterone is the hormone made in large amounts during pregnancy, it is also a diuretic, and it decreases the risk of blood clots, has antidepressant effects and helps to build bone. Progestins can cause miscarriages, fluid retention and blood clots, and it is linked with mood swings and can reduce bone density.

Hormones Decline with Age

The fact is that hormone levels do often decline dramatically later in life. Testosterone deficiency can result in lack of sex drive, lack of motivation and depression in both men and women. Lack of oestrogen results in vaginal dryness and lack of progesterone, from which all these hormones can be made, results in lack of everything. Also, progesterone dampens down adrenal hormones so a common effect of progesterone deficiency is more anxiety, bursts of anger, insomnia, tight and aching muscles, all of which are often found in the menopause.

As you can see from the diagram below progesterone is the ‘mother’ of all hormones, itself made from cholesterol. (Beware statin enthusiasts – driving down cholesterol too low eg below 3.5mmol/l could lead to hormone deficiency.)


The body will always make cortisol – the stress hormone – in preference to anything else because it is to do with our immediate survival. This may not actually be the case when you get stressed watching the news but your body thinks it is so. Consequently, DHEA levels go low. The more stressed you are the higher the cortisol and the lower the DHEA, until you are completely burnt...

Want to keep reading? Members have full access...

Join Today!


First month free

Then £7.99 per month & free cancellation at any time

FREE health check

Find out your health score & see how healthy you are

Personal Health Plan

Detailed report, analysis & tailored action plan

Free Vitamin D3

With your first purchase at HOLFORDirect (suitable for vegans)

Save money

20% off all Patrick Holford supplements & events plus free delivery over £30

Exclusive Health support

Ask Patrick your questions, access to Low GL recipes & research updates