Why Fiber Matters in a Balanced Diet

Fiber doesn’t get as much attention as protein or vitamins, but it plays an important role in a balanced diet. Many health organizations note that most people eat less fiber than recommended. The good news is that a few simple swaps can make a real difference.

What is fiber?

Fiber is a type of carbohydrate found in plant foods that our bodies can’t fully digest. Instead of being absorbed like other nutrients, it passes through the digestive system, where it has several useful roles.

There are two main types:

• Soluble fiber dissolves in water to form a gel-like substance. It’s found in foods like oats, barley, beans, lentils, apples and citrus fruits.
• Insoluble fiber doesn’t dissolve in water and adds bulk. It’s found in wholegrain foods, nuts, seeds, and the skins of many fruits and vegetables.

Most plant foods contain a mix of both, so eating a variety is the easiest approach.

Why fiber matters

According to public health organizations, a diet rich in fiber is associated with a range of benefits, including:

• Supporting regular digestion. Fiber adds bulk and helps keep things moving.
• Helping you feel full. High-fiber foods are often more filling, which can help with appetite.
• Feeding gut bacteria. Some types of fiber act as food for the bacteria that live in your gut.
• Supporting overall health. Diets higher in fiber are linked with better heart health and a lower risk of some long-term conditions.

Fiber works best as part of an overall balanced diet. It isn’t a quick fix, and no single food is magic.

How much fiber do you need?

Recommendations vary by country. For example, the NHS advises that adults in the UK aim for 30 grams of fiber a day, while US dietary guidelines base recommendations on about 14 grams for every 1,000 calories eaten. If you’re far below these amounts, the most important thing is to increase gradually.

Easy ways to eat more fiber

You don’t need to overhaul your diet. Try one or two of these swaps:

• Breakfast: choose porridge oats, wholegrain cereal or wholegrain toast. Add fruit, seeds or nuts.
• Lunch: add beans, lentils or chickpeas to salads and soups. Choose wholegrain bread or wraps.
• Dinner: fill half your plate with vegetables. Try brown rice or wholewheat pasta, or mix them half-and-half with white versions.
• Snacks: fruit, raw vegetables with hummus, a small handful of nuts, or plain popcorn.
• Keep the skins on potatoes and other vegetables where possible.

Increase fiber gradually

Adding a lot of fiber very quickly can cause bloating or discomfort for some people. Increase it gradually over a few weeks and give your body time to adjust.

Don’t forget to drink

Fiber works best with enough fluid. As you eat more fiber, make sure you’re drinking regularly throughout the day. Water is a great choice.

A sample high-fiber day

• Breakfast: porridge made with oats, topped with berries and a spoonful of ground flaxseed
• Lunch: lentil and vegetable soup with a slice of wholegrain bread
• Snack: an apple with a few almonds
• Dinner: bean chilli with brown rice and a side salad

This is just an example, not a prescription. It shows how fiber can come from many different foods across a day. For more ideas, see Everyday Foods That Support Digestive Wellness and How to Build a Balanced Plate.

A note on individual needs

Some people, including those with certain digestive conditions, may need different amounts or types of fiber. If you have ongoing digestive symptoms, such as pain, changes in bowel habits or bloating, please speak with a doctor or registered dietitian before making significant changes.

Further reading

• NHS, How to get more fibre into your diet
• Harvard T.H. Chan School of Public Health, Fiber