Seasonal Eating and the Gut Microbiome: Have We Forgotten How to Eat With the Seasons?

Eating a variety of real foods can not only be adventurous; it is healthy.

When we eat the same foods all year, we may be missing one of nature’s easiest ways of giving our diet—and our microbiome—more variety.

There is something very unusual about the modern grocery store that most of us barely notice anymore. We can walk into one in Nova Scotia in January and buy strawberries, cucumbers, lettuce, mangoes, tomatoes, avocados, and almost anything else we might have bought in July. That access is an extraordinary convenience, and I am not necessarily suggesting that we should give it up, but it has changed something fundamental about the way we eat: the season no longer has much say in what goes into our grocery cart unless we deliberately allow it to.

That change becomes even more interesting when we look at the way many of us shop. We are creatures of habit. We leave the house with approximately the same grocery list, walk approximately the same route through the store, put the same familiar foods into the cart, and then make variations of the same meals we have been making for years. There is nothing particularly wrong with that, especially when those foods are nourishing and we enjoy them, but autopilot can create a surprisingly narrow diet without us ever deciding to eat narrowly. We may technically have access to hundreds of foods while our own microbiome sees the same twenty or thirty ingredients over and over again.

For most of human history, that would have been much harder to do. Before global transportation, refrigeration, and supermarkets capable of sourcing food from almost anywhere in the world, the place where you lived had a tremendous influence on what you ate. Foods appeared, disappeared, and returned according to growing seasons, migrations, harvests, and what could be stored, dried, fermented, preserved, caught, or hunted. Variety doesn’t just mean different colours on your plate, but it also means eating differently throughout the year.

That is a distinction worth bringing back.

What If Variety Is Meant to Happen Over Time?

We often talk about dietary variety as though every plate must contain enormous diversity, but there is another kind of diversity that happens across weeks and months. Spring foods begin appearing, summer brings another abundance, autumn changes the harvest again, and winter traditionally shifts us toward stored vegetables, roots, preserved foods, and whatever can be carried through the colder months. Different seasons naturally expose us to different plant foods, different fibres, different colours and different plant compounds, and all of that becomes relevant when we begin thinking about the digestive microbiome.

Our microbiome is not one organism. It is an ecosystem containing enormous numbers of microorganisms with different jobs and different preferred foods. Some thrive on particular fibres, others interact with resistant starches or plant compounds, and the substances they produce can influence the intestinal environment and communicate with systems throughout the body. When we eat, we are not only feeding ourselves; we are feeding an ecosystem.

And ecosystems tend to do better with diversity.

If the same foods appear every morning, every lunch, every supper, and every week of the year, we continue supplying many of the same fibres and plant compounds. Changing our foods with the seasons gives us a way to rotate those inputs without needing an elaborate nutrition program. Apples replace berries. Squash and root vegetables begin appearing where tender summer vegetables once dominated. Cabbage, leeks, pears, and other autumn foods find their way onto the plate, and a few months later the landscape changes again.

The value is not that one food is magically superior to another. The value is that the menu keeps moving.

Your Microbiome Should be Moving With the Seasons Too

The digestive microbiome is remarkably adaptable. When the diet changes, the microbial environment can change with it. Traditional populations whose food supply still changes considerably from one season to another have shown seasonal shifts in the organisms living within the digestive tract, which gives us an interesting glimpse into something modern diets may have made much less obvious.

We often assume that having every food available all year automatically gives us greater variety, but it can actually do the opposite if that abundance allows us to buy the same foods all year long. For many years, Nature’s limits forced us to rotate our diets; now we have to choose it.

That does not require abandoning the foods we love or refusing imported foods. It means recognizing that one of the easiest ways to introduce new fibres, colours, phytochemicals, textures, and food-associated microorganisms into the diet is to pay attention to what is newly available around us.

This is where the holistic view of eating within our climate begins to make sense. We live inside an environment even when modern life does a remarkable job of separating us from it. We can spend a hot August day in air conditioning and a January day in a house heated to twenty-one degrees, drive from one controlled environment to another, and barely experience the temperature outside. Yet our daylight still changes, our local growing season changes, our food landscape changes, and our bodies remain connected to the world in which we live.

We do not need to pretend we are living as our ancestors did to benefit from remembering that connection.

What Is the Season Offering Us?

Summer food and autumn food naturally look different. During warmer months, many of the foods that become abundant are high in water and tend to be lighter and easier to eat—berries, cucumbers, tomatoes, greens, and other fresh produce. As the growing season turns toward autumn in places such as Nova Scotia, we begin seeing more apples, squash, potatoes, carrots, beets, cabbage, turnips, and other foods capable of storing well and carrying us farther into the colder months.

Those autumn foods do more than create a different-looking plate. They change the types of fibres, resistant starches, colours and plant compounds reaching our digestive tract. Apples bring different fibres and polyphenols than summer berries. Cabbage and other members of its plant family bring another collection of compounds altogether. Root vegetables and squash bring another type of nourishment again. We do not need to memorize all of that chemistry every time we make supper. Nature has already made dietary rotation much simpler by changing what grows well at different times of year.

This also connects beautifully with the question we explored in Nutrition

Matters last week:

What do I need this meal to do for me?

This week I would add another:

What does my environment have available to help me do it?

Those are different questions, but together they bring awareness back to eating.

Local Food Gives Us More Than Food

There is another part of this that I think is easy to overlook. When we choose food grown closer to home, we shorten the distance between ourselves and the people producing it. That gives us an opportunity to ask questions that are almost impossible to ask of a carrot that has travelled thousands of kilometres. How was this grown? What do you spray your crops with? What varieties do you grow? When was it harvested? What is coming next month?

Local does not automatically mean organic or free of agricultural chemicals, and it is important to recognize that. What local food can give us, however, is greater access to the conversation. When we buy directly from a farm, farmers’ market, or grower, we can ask how they work and decide what matters to us.

Food grown close to where it will be eaten can also have another advantage: it may be harvested closer to ripeness and reach us sooner. Food that does not need to spend long periods travelling or sitting in storage tends to be fresher, with better flavour and, depending on the food, better retention of some nutrients.

There is also the larger value of helping local farms remain viable. Buying locally can help keep families on their land, keep agricultural land producing food, and keep knowledge about growing food within our communities. To me, that belongs within holistic nutrition as well. Health is not only the nutrient content of the carrot; it includes the food system that allows carrots to continue being grown.

Your Gut Is Part of Your Immune Environment

The intestinal microbiota forms part of the body’s biological barrier. Beneficial organisms compete with potentially harmful organisms for space and nutrients, help shape the environment of the intestinal tract and interact with our immune responses. The fibres and plant compounds that reach the colon become raw materials from which gut organisms produce other compounds that help support the intestinal environment.

So when we talk about building and maintaining a healthy microbiome, we are not talking about something separate from the rest of the body. We are talking about a living ecosystem that interacts constantly with the digestive tract, the intestinal barrier, and the immune system.

That is what makes variety especially important.

Eating seasonally does not mean that one particular autumn vegetable contains a special ingredient that guarantees we will not become ill during the winter. The value is broader than that. Changing seasonal foods bring changing fibres, resistant starches, colours, polyphenols and plant compounds, and those different inputs help create a more varied environment for the organisms living within us.

A more diverse food supply gives the microbiome more to work with. That may be one of the most practical reasons to let the seasons influence our plate.

Autopilot May Be the Bigger Problem

This may ultimately be the part of seasonal eating that matters most for many of us. It is very easy to build a healthy routine and then stop looking at it. The same smoothie. The same breakfast. The same salad ingredients. The same three vegetables with supper. The same fruit in the bowl. The same grocery list every Saturday.

There can be enormous value in reliable routines, particularly when they keep us nourished and prevent us from defaulting to heavily processed foods. But even a good routine can eventually become a rut if it removes curiosity from our diet.

This is where seasonal eating can give us a way out of autopilot.

Instead of trying to overhaul everything you eat, pay attention to what is appearing because the season changed. Look around the produce section differently. Visit a farmers’ market. Ask a farmer what is especially good right now. Notice the vegetable you normally walk past because you have never cooked it before.

One New Food Is Enough to Start

The next time you shop, do not begin with a list of twenty foods you now think you should eat. Choose one food that is in season where you live, and that is not normally in your cart. Maybe you have seen it dozens of times but have no idea what to do with it. Find out. Look for a recipe that actually sounds appealing. Cook it in a way you think you will enjoy and see whether it earns a place at your table while it is available.

Then choose a different one next week.

By the end of a season, you may have eaten a considerably wider range of foods without following another diet, counting another number or turning food into another job. Your grocery cart will begin changing, your meals will begin changing, and your microbiome will receive a changing supply of fibres and plant compounds along the way.

Maybe Nature’s Menu Was Never Meant to Stay Still

Modern life gives us something generations before us could scarcely have imagined: the ability to eat almost anything at almost any time.

That is a gift, but it is a gift we can use thoughtfully.

We can enjoy an orange grown thousands of kilometres away, but we may also eat an apple that was grown in the orchard down the road. We can use frozen berries in February and still cook September’s squash, roots, and cabbages in our meals as well. We can keep the healthy foods that serve us well from each season during its season and still enjoy foods we love from other places. A variety of natural foods is the key to health.

Seasonal eating is not about restricting the foods that come from elsewhere. It is about allowing the place where you live to contribute something to your plate.

From a holistic nutrition perspective, that gives us far more than a seasonal recipe. It gives us changing nutrients, changing fibres, changing plant compounds and greater dietary diversity. It gives our gut microbiome a broader range of materials to work with, keeps us engaged with our food instead of purchasing it entirely on autopilot, and reconnects us with the environment changing outside our door, whether our furnace and air conditioner allow us to feel those changes or not.

Mother Nature does not produce exactly the same foods in exactly the same way twelve months of the year.

Maybe our plates were never meant to stay exactly the same either.