When I was in my early twenties, I became very close to my boyfriend’s Mum, who was going through menopause at the time. My own mother never talked much about her experience of ‘the change’, but Helen discussed her menopausal trials and tribulations quite openly with me. She found a willing listener, not just because I cared about her, but also because I was in naturopathic college and hearing about her real-life experience was far more compelling to me than the dry lists of symptoms I was studying in my endocrinology textbook.
Aside from the dreaded hot flushes and night sweats, Helen was perturbed by the way her body shape was changing. She found that although her weight was relatively stable, where it was distributed was altering significantly. In short, she was growing a ‘spare tyre’ around her midsection, and she didn’t like it one bit.
Helen’s experience, as it turned out, was far from unique.
When women are in their fertile years, the oestrogen produced by their ovaries deters fat deposition around the midsection, but causes fat to accumulate in their hips and thighs. This so-called gluteofemoral fat is stubbornly resistant to being shifted, as countless women who have tried to alter their ‘pear shape’ through diet and exercise, know only too well.
If it gives you any comfort, while gluteofemoral fat makes wearing skinny jeans a doubtful proposition, it’s not associated with any health risks. In fact, having a higher ratio of gluteofemoral fat to abdominal fat is associated with better metabolic and cardiovascular health.
Only the hormonal milieu of pregnancy and breastfeeding facilitates the breakdown of gluteofemoral fat – unsurprisingly, since the whole purpose of butt and thigh fat is to provide a ‘calorie bank’ that helps women meet the enormous energy cost of growing babies.
The menopausal transition is marked by the gradual winding down of oestrogen production by the ovaries. That’s an inevitable part of the aging process for women. However, the accumulation of the spare tyre isn’t inevitable, as the authors of an article published in the journal Trends in Endocrinology & Metabolism, called ‘Estrogen and Microbiota Crosstalk: Should We Pay Attention?’ explain:
“Sedentary lifestyle, restricted mobility, and western-style, fat- and sugar-rich diets, promote obesity, and when combined with low estrogen levels in postmenopausal women, make postmenopausal women more susceptible to weight gain, fat redistribution to abdominal areas, dyslipidemia, hypertension, and insulin resistance; the major hallmarks of metabolic syndrome.”
Estrogen and Microbiota Crosstalk: Should We Pay Attention?
In other words, when it comes to growing an apple shape, menopause loads the gun, but lifestyle pulls the trigger.
But what is it about that western-style diet that turns pears into apples, and increases postmenopausal women’s risk of developing metabolic and cardiovascular disease?
According to Karen Chen and Zeynep Madak-Erdogan, the authors of the article,
“Emerging evidence suggests an interaction between estrogens and the microbiome that might affect metabolic rate, bodyweight, and adiposity.”
Estrogen and Microbiota Crosstalk: Should We Pay Attention?
It turns out that oestrogens and gut bacteria have a complex relationship with each other, and our dietary patterns and exercise habits profoundly influence both.
For example, the phytoestrogens genistein and glycitin, found in abundance in soy foods, boost the growth of the beneficial Bifidobacterium species, while keeping in check members of the Clostridiaceae, which are associated with numerous diseases affecting humans.
Daidzein, an isoflavonoid that is also found in soy foods, is metabolised by certain gut bacteria into equol, a substance which improves blood sugar regulation and lowers LDL cholesterol. Not everyone harbours these equol-producing bacteria; those who don’t are more likely to be obese than those who do, and in fact, more than 50% of obese individuals are equol non-producers.
Bacteria also transform our endogenous oestrogen into a range of compounds, called metabolites. Some of these metabolites protect against breast cancer.
Interestingly, people who have a highly diverse gut microbiome (which is supported by the consumption of a varied, wholefood plant-based diet and regular exercise) convert more oestrogen into metabolites. This low ratio of ‘parent’ oestrogen to metabolites is associated with protection against breast cancer.
On the other hand, eating a diet high in fats tips the balance of bacteria in an unfavourable direction, increasing the proliferation of gram negative bacteria which produce endotoxin, a highly inflammatory compound associated with a wide range of disease conditions including type 2 diabetes, fatty liver disease and cancer.
If only I had known this at the time I knew Helen! Not only could I have helped her lose the spare tyre that bothered her so much, but even more importantly, I could have offered her gut bug-friendly diet and lifestyle advice that would reduce her risk of diabetes and breast cancer.
Unfortunately, back in the early 1990s, the study of the human microbiome was in its infancy. No one had any idea of the diverse range of functions our gut bugs perform for us… and how many disease processes are driven by the type of imbalanced gut flora we see in people eating the typical high fat, high sugar, low fibre Western diet.
The take-home message for older women is that nurturing the ‘garden in your gut’, by eating a wholefood plant-based diet and getting regular exercise, is probably the most important step you can take to maintain a healthy body composition and shape, and prevent so-called ‘age related’ diseases such as diabetes and breast cancer.
