Cooking with fibre: simple tips to preserve nutrients and boost flavour

Fibre plays a starring role in our health. Think of it as nature’s broom, sweeping through the digestive system and keeping things running smoothly. And while we might already know that foods like veggies, lentils, and nuts are full of fibre, it’s worth knowing that cooking and peeling them can take away some of that fibre too. That means it’s not just about what we eat, it’s also about how we prepare it.

Luckily, a few small changes in the kitchen can make a big difference in how much fibre ends up on your plate. In this article, we’ll give you some simple tips to help you keep (and boost) the fibre in your meals, so you’re getting the most out of your food.

What happens to fibre when we cook it?

When we cook foods that are high in fibre —  like vegetables, beans, or potatoes —some of the fibre starts to break down. One type of fibre, called pectin, helps hold plant cells together and gives food its firmness. But when we cook, the pectin starts to break apart. That’s why hard vegetables can become soft and mushy, like when firm potatoes turn into mashed potatoes.

With beans and other legumes, their outer shell is tough because of pectin. To help legumes cook faster, we can soak them in water before cooking. This softens their tough pectin shell, and helps beans cook more quickly and evenly.  

Smart cooking tips for more fibre and flavour

When it comes to fibre, some cooking methods are better than others, and a few simple tweaks in the kitchen can go a long way. We’ve pulled together easy tips so that next time you’re preparing a meal, you can make a few small changes and get even more benefit from every bite.

Keep the peel

Many fruits and vegetables have lots of fibre and nutrients hiding in their skins. Potato skins and apple skins are good sources of fibre and vitamin C. Instead of peeling them and losing all that goodness, just wash them well and eat or cook them with the skin on. 

Love your leftovers

Some foods like potatoes, rice and pasta can produce a special kind of fibre called resistant starch. When you cook and cool these foods, the starches change and give you this resistant starch that’s really good for your gut. Even if you reheat them later, the resistant starch stays high. So, dishes made with leftovers like potatoes and rice are packed with fibre and still full of nutrients. 

Choose your cooking method wisely 

• Boiling smart: If you are boiling vegetables, use as little water as possible. Also, don’t overcook them. Try to use the leftover water from boiling in soups or sauces to keep all the vitamins.
• Steaming: When you steam vegetables like broccoli or carrots, they lose very little vitamin C, so it’s a better way to preserve all the vitamins and minerals. 
• Roasting: Cooking veggies this way brings out their natural sweetness. It’s also a great way to keep B vitamins. When you roast tomatoes, it can also increase lycopene, a healthy antioxidant that’s good for heart health. 

Fibre-rich foods and the best ways to cook them

Some of the food groups rich in fibre are: legumes (like lentils, chickpeas, black beans, kidney beans), vegetables, fruits, whole grains (like brown rice, oats, quinoa, barley) and nuts and seeds. Let’s explore some delicious and nutritious cooking techniques to preserve as much fibre as we can from these foods.  

Cooking with legumes

Legumes like lentils, chickpeas, kidney beans, and black beans are some of the best foods you can eat for fibre.² They’re also full of protein and tend to be more affordable than meat or tofu. You can save time and fuss by using cans of precooked chickpeas or beans. Or you can use dried legumes and prepare them following the instructions on the packet. Top tip: dry kidney beans must be boiled in fresh water for at least 30 minutes to destroy a natural toxin that could give you a sore tummy. Don’t use a slow cooker for this, as it might not get hot enough. Once cooked properly, add them to soups or stews. 

Cooking with vegetables

Vegetables don’t have as much fibre as legumes, but they’re packed with all sorts of helpful vitamins and minerals. That’s why it's great to think about ways to lock-in fibre while still creating delicious meals. 

• Roast and go
  Toss your veg in a bit of oil, sprinkle it with salt and your favourite herbs or spices, and roast in a hot oven. Remember to keep the skins on squash and potatoes for extra fibre and minerals. 
• Lock in nutrients by steaming
  Steaming is a gentle way to cook most vegetables in about 10 minutes. Use a steamer pan or a metal sieve (metal strainer) over a pot of boiling water. Pop a lid on top (not all the way closed, you want to let a bit of steam out) and you’re good to go. Bonus: this method keeps in the most nutrients.⁴
• Save time by stir-frying
  This is a fast way to cook and a great way to keep fibre, flavour and nutrients. Use a wok for best results and cook on high heat for a short amount of time.

Cooking with grains 

Whole grains and whole-grain foods are a great source of fibre.

• Treat whole grains like sponges
  Think of grains such as brown rice or quinoa as tiny sponges. Place them in two to three times their volume of cold water, then let them simmer (boil gently) until they’ve soaked up enough water to feel tender. Check the packet for exact cooking times because each grain has its own preference.
• Brown rice isn’t in a rush
  Brown rice still wears its fibre-rich bran layer, so it needs around 40–50 minutes to cook, rather than the 10–15 minutes white rice takes. Allowing this extra time means it’ll finish soft and chewy rather than crunchy.
• Toast grains for a flavour boost
  Before adding water, warm whole grains in a dry pan over high heat for a minute or two. This unlocks a nuttier aroma. After that, pour in the water and continue cooking as usual.

Cooking with nut and seeds 

Nuts and seeds are packed with healthy fats, fibre and minerals. Even a small handful adds flavour, texture and a little extra sparkle to your meal.

• Sprinkle as a finishing touch
  Scatter a handful of whole nuts or seeds over your meal just before serving. It’s an easy way to boost fibre and minerals and make your dinner look fancy.
• Use nut and seed pastes in dressings
  Peanut butter or tahini (sesame seed paste) make simple, flavourful bases for salad dressings. Stir them into a little lemon juice, olive oil and seasoning for a creamy, fibre-rich addition to side salads and slaws.
• Add seeds to baking
  You can stir chia seeds into muffin batter for a gentle crunch, or press poppy seeds into the top of homemade bread before it goes in the oven. They add both texture, fibre, and extra nutrition.
• Toast for deeper flavour
  Bring out the best in sesame, pumpkin or sunflower seeds by toasting them briefly in a dry pan over medium heat. As they warm, they release a nutty aroma and a richer taste. 

Maximise your fibre

We know that fibre is tough and holds up well during cooking, especially when you use methods like steaming, roasting, and stir-frying. Simple choices like leaving the skins on your fruits and veggies, or eating leftover potatoes, pasta, and rice are great ways to get the most fibre from your food. Adding lentils, beans or roasted veggies to your soups, stews, and salads, or even sprinkling nuts and seeds on top, is a tasty way to get more fibre without trying too hard. These small changes mean you’re not just eating fibre, you’re getting the most out of it, and your body will thank you for it.