Prebiotics 101—Everything you need to know

What exactly are prebiotics, and should you be having more of them? We look into the facts.

At Heights, we love probiotics . That’s no secret. But what about prebiotics? People often ask why we don’t include them, and whether they should be taking a prebiotic supplement. So we’re diving into the world of prebiotics—what they are, what they do, and the best ways to get the right amount of prebiotic fibre in your diet.

What are prebiotics?

Prebiotics are special types of fibre. You’ll sometimes see them referred to as prebiotic fibre, or dietary fibre, particularly in Europe (where regulations prohibit using the word ‘prebiotic’ on labels).

What makes it special is that we can’t break them down at all. We lack the digestive enzymes, which means that, when they arrive in the gut, the sugars are still intact. But while we can’t break them down, our gut bacteria can, so the prebiotics act as food for our bacteria.

There are all sorts of fibres that could be considered prebiotic. Some of the most common are:

  • Inulin

  • Fructooligosaccharides (FOS)

  • Galactooligosaccharides (GOS)

  • Pectin

  • Beta-glutans

Lots of long, hard-to-pronounce names, but in effect, they’re complex sugars, found in plants.

Why are prebiotics important

Like every other living thing, our gut bacteria need nutrition. They need to eat. Indigestible fibres arrive in the gut still whole, ready to be broken down and digested by our gut flora (with carbon dioxide produced as a byproduct). Getting enough prebiotic fibre is important for the health of the gut microbiome —helping the bacteria stay healthy, strong, and effective.

On top of that, all fibre, prebiotic or not, is important for your digestive health. It adds bulk to stool, and helps maintain regularity.

Do you need a prebiotic supplement?

Lots of supplements contain prebiotics (or dietary fibre), claiming that it will help with digestion, or gut flora, or survivability, or many other things. But it’s important to be sceptical of such claims.

According to Heights Head of Nutritional Reach Sophie Medlin , a meaningful dose of prebiotics needs to be at least 4 grams. Below that, it’s just not worth it. But a standard capsule can only contain less than 1 gram, and that’s as a maximum. There’s not really any point taking such a small amount—it won’t have an effect.

On top of that, you need to be aware that many of the symptoms associated with probiotic supplements actually come from prebiotic fibre. If you’ve ever eaten Jerusalem artichokes, you’ll know what that feels like.

The best ways to add prebiotics to your diet

So don’t bother with any supplement claiming to contain prebiotics or dietary fibre. But that doesn’t mean you should be ignoring them in your diet. At Heights, we advocate a food-first approach for prebiotics—it’s the best way to get a variety of different fibres to your gut bacteria in meaningful amounts. Plus you get the benefits of all the other vitamins minerals and nutrients in the food.

That means eating plants—aim for up to 30 different plants a week. It sounds like a lot, but with a bit of creativity, you can incorporate those into your diet, and make sure your gut bacteria are getting all the inulin, GOS, FOS, and other prebiotics that it needs.

5 best foods for prebiotics

All sorts of plants contain some amounts of prebiotics, and variety is important. But if you’re looking for some foods that are particularly high in these fibres, this is where to start.

  • Chicory. The root of the chicory plant is particularly high in inulin—in fact, most industrial extraction of prebiotics comes from chicory.

  • Jerusalem artichokes. Also known as sunchokes, these knobbly tubers aren’t artichokes (despite the name). But they do pack a lot of prebiotics into a small package, and have a reputation to match. Jerusalem artichokes are in season in the winter, and are particularly good in salads and soups.

  • Alliums (eg. onions, garlic, leeks). Alliums are the backbone of cuisines all around the world, adding depth, flavour, and bulk to our dishes. They’re also full of prebiotics.

  • Legumes. Cheap and filling, legumes are a great way to make a meal go further, or to add protein to a plant-based diet. They also contain galactooligosaccharides, making them a healthy, delicious addition to any meal.

  • Whole grains (eg. barley, oats, wholewheat). Grains come either whole or refined. The difference is the germ and the bran, and these are the parts that contain prebiotics. So look out for barley, oats, brown bread, and brown rice.

A balanced diet, with plenty of these foods, along with a variety of other plants, will give you all the prebiotic fibre your gut bacteria need, without any additional supplements.

Are all supplements useless, or can your diet sometimes use a little bit of help. There are lots of different opinions out there, so we cut through the noise to study the facts. Learn more now .


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