Your gut & beyond.

We have known for a long time that the gut bacteria helping to keep us healthy rely on the food we eat to survive and produce those health benefits. As a general rule in healthy adults, the more diverse the bacterial population the better for health, and this means consuming a more diverse diet.

Just as different humans prefer different things to eat, so different bacterial species have their own ‘dietary’ preferences. These diverse bacteria interact to produce the many metabolic products (molecules) that keep us healthy.

Being mindful of the health of our gut bacteria is sensible at any age, but during menopause, eating to promote a happy gut population can have positive knock-on effects on symptoms outside the gut as well as within it.

How exactly does the bacterial community within our gut contribute to our health?

One important example is the synthesis of specific fermentation products (short chain fatty acids, or SCFAs) that allow the human cells lining the gut to grow and reproduce, maintaining an essential healthy cell turnover.

Some of these same fermentation products also suppress inflammation and inhibit the growth of cancerous cells.

And the very existence of these fermentation products, which are weak acids, lowers the pH in the gut (or intestine) helping to prevent the growth of bacteria that may both make us sick, like some food-borne pathogens; or less dramatically, less likely to experience bloating and other symptoms of IBS, cravings and food sensitivities - all too common in menopause.

Going beyond the gut

In recent years much research has been done determining that the products of a healthy gut microbiota also have health benefits way beyond the gut. The lowering of pH that prevents growth of pathogens, also increases absorption of calcium, improving bone health – typically a priority postmenopause.

Some of the SCFAs can interact with specific receptor molecules in the gut, telling us that we are full and to stop eating, thus having an impact on weight gain.

Bacterial products are also now known to improve mood, help strengthen the immune system, improve cardiovascular health and… the list goes on.

One of the most important recent findings is that the two-way communication pathway between the gut and the brain is influenced by products from microbes. Microbial production of the SCFA butyrate may be important in maintaining brain function and preventing cognitive decline.

There is a growing body of evidence that people living with Alzheimer’s disease tend to have lower amounts of both butyrate-producing bacteria and butyrate itself in faecal samples.

Studies have also shown that supplementing the diets of ageing mice with fibre, or directly feeding butyrate, improves their ability to perform tasks and remember things.

Clearly, research into Alzheimer’s and other dementias has yet to provide concrete answers, but these findings suggest that sufficient fibre consumption, alongside other healthy lifestyle choices, may help maintain brain health as we age and prevent cognitive decline.

How do we unlock these gut benefits?

For many of the bacteria providing this myriad of health benefits, their preferred energy sources are foods containing fibre. Eating plenty of fibre is crucial to maintain microbial activity – and the more different types of fibre, the more different types of microbe will survive.

Diets high in complex carbohydrates, particularly fibre, have many beneficial effects. As well as increasing concentrations of beneficial bacterial metabolites like butyrate, fibre is also important for decreasing gut transit time, which reduces exposure to potentially toxic dietary components and any byproducts of less desirable microbial metabolism.

Diets which are high in protein and low in fibre result in more protein fermentation by bacteria in the colon, releasing harmful compounds (including nitrosamines and heterocyclic amines). During a four-week study, a high protein-low carbohydrate diet significantly decreased cancer-protective metabolites and increased concentrations of hazardous metabolites, suggesting long-term adherence to such diets may increase risk of colonic disease.

Plant-based foods provide us with fibre. These include legumes (lentils, beans, chickpeas); cereals and whole grains (oats, barley, brown rice); fruits; vegetables; nuts and seeds. The target for a healthy adult is to consume 30g fibre per day yet according to the NHS most people only manage 20g/day. For teenagers the target is 25g/day, but most only consume about 16g.

With so many different options for fibre-rich foods, with a few simple changes, it can be easy to eat more. Simple dietary swaps can help us reach that target 30g/day: choose higher fibre breakfast cereals and whole grain bread/rolls; keep skins on potatoes (for mashing, baking, or even making chips); have nuts (unsalted), chopped fresh fruit, raw vegetables or even higher fibre biscuits, including oatcakes, as snacks.

More subtle tricks to increase family intake include mixing whole wheat and white pasta, mixing brown and white rice, adding beans, pulses or extra vegetables to stews and curries, and using any leftover or past-its-best veg in homemade soups.

More benefits of plant-based foods

As well as high fibre content, plant-based foods of course also contain many other important nutrients including vitamins, antioxidants and phytochemicals (molecules that mop up damaging free radicals in our gut preventing cell damage). These micronutrients are also important for health and are released following fibre degradation and fermentation.

Simple guidance includes ‘eat a rainbow’ or setting oneself a challenge to consume 30 different plant-based foods a week (this would include herbs and spices).

Scientists are investigating how the diversity of different foods contributes to the diversity within the gut microbiota – and therefore their metabolites. Fresh, frozen and tinned (without added sugar) products are all equally important fibre sources.

The most widely advocated high fibre diet – with the most research proving its important health benefits – is the Mediterranean diet. In addition to a higher fish consumption, the Mediterranean diet is generally higher in fruit, vegetables, cereals and pulses and lower in refined foods than a standard Western diet, providing lifelong health benefits. It is no coincidence that there are more people in the “healthy ageing” category in countries where this type of diet is prevalent.

The DASH (Dietary Approaches to Stop Hypertension) diet designed to lower high blood pressure is also focussed on increasing consumption of fruit, vegetables, and cereals while limiting salt, sugar and saturated fat intake.

The MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet is basically a merging of the Mediterranean and DASH diets, focusing on improving brain health, while also benefiting heart health.

Prebiotics can be important additional sources of soluble fibre and help to maintain a healthy microbiome and improve bone, heart and mental health. Since they also act as natural sweeteners – think of the caramelisation of slow-cooked onions - but are not digested by human enzymes, they provide sweetness without blood glucose spikes and improve your meal’s glycaemic load. Prebiotics can be useful supplements to a healthy high fibre diet, and can assist the transformation of a low fibre diet into a higher fibre diet.

Some people may not want to eat more fibre are because they feel it causes flatulence and bloating. If you normally have a very low fibre intake, it can help to increase fibre consumption slowly, very slowly, allowing your body (and gut bacteria) to adjust to the change in your diet.

However, since gas production is a natural part of digestion by gut microbes it can’t completely be avoided.

If you are planning to up your fibre intake, you should also be mindful of your intake of fluids. Increasing fibre when subsisting on the odd cuppa during the day, can be a recipe for constipation.

Take-home message

Fibre is so much more than an important source of roughage helping our digestive systems and improving gut transit. It is a key food source for our gut microbes, which during degradation and fermentation release important bacterial metabolites that circulate around the body improving brain, heart and bone health. Since there are so many different types of fibre-containing foods, relatively simple diet changes are enough to achieve the recommended intake, with potential health benefits all around the body. So next time you think “I can’t eat fibre”, rephrase the sentence into “I can’t eat fibre at the moment” – and work on gradually building your tolerance slowly, but deliberately*.

If you would like targeted support to improve the amount & diversity of your fibre intake, why not join me for the latest iteration of my 3-week online course MenoMelt? 

With one thing & another it’s been a couple of years since I last ran this course, but it is still the same framework that has led to weight loss, reduced anxiety, better sleep, improved mood and overall joie de vivre in hundreds of women!

Returning participants will find new elements, & given the prevalence of weight loss meds, I can confirm that it works very well alongside Mounjaro, Ozempic, etc.

If you have previously joined me for MenoMelt, drop me a line to receive your discount code.

Otherwise, if you’re fed up of the changes in your body – whatever they are - we start on April 19^th and I look forward to getting to know you a little better over the course of 3 weeks.

If you’d like to chat first to understand how it might work for you, please drop me a line. Otherwise, full details are here.

*If you have an inflammatory intestinal condition, always speak with your doctor before making any dietary changes.