Fiber is often thought of as the indigestible component of plant-based carbohydrates that our digestive systems cannot break down. Ensuring adequate fiber intake is linked to a diminished risk of various health conditions, including heart disease, stroke, type 2 diabetes, and colon cancer. Furthermore, consuming fiber-rich foods not only helps you feel full longer but also enhances your digestion and promotes regularity. Incorporating fiber into your daily meals fosters gut health, increases the diversity of gut bacteria, aids in maintaining a healthy weight, balances cholesterol levels, and regulates hormones.
Explore our focus on high-fiber diets, 20 fiber-rich foods, and check out our favorite high-fiber recipes, including kidney bean curry and chickpea burgers.
Is All Fiber the Same?
Not all fiber types are created equal; they can be categorized into three main types:
Soluble Fiber
Soluble fiber absorbs water and transforms into a gel-like substance. Common sources include gums, pectin, beta-glucans found in oats, and the fiber from psyllium husks. If you’re familiar with making jam, you’ll recognize pectin as essential for achieving the perfect consistency.
In our bodies, soluble fibers slow down digestion and nutrient absorption. However, be cautious as they may interfere with the absorption of medications. Consult your GP if necessary.
Insoluble Fiber
Often referred to as “roughage,” insoluble fiber remains unchanged during digestion and serves as a bulking agent that helps prevent constipation.
A lifelong diet rich in insoluble fiber may also reduce the likelihood of developing conditions like hemorrhoids and diverticulitis.
Fermentable Fiber
Fermentable fibers are broken down by gut bacteria and serve as an energy source for them. In return, the bacteria produce beneficial byproducts known as short-chain fatty acids (SCFAs), which nourish colon cells, strengthen the immune system, enhance food tolerance, and modulate our allergy responses.
Resistant starch is a type of fermentable fiber that, while resistant to digestion, can be fermented, leading to various health benefits such as improved blood sugar levels, better appetite regulation, and enhanced digestion.
What is Fibermaxxing?
Popularized on social media, ‘fibermaxxing’ involves increasing your fiber intake, potentially incorporating fiber-rich foods like prunes or even using supplements like fiber powders.
However, additional fiber may not be safe for everyone, depending on individual health conditions. For instance, if you’ve been diagnosed with diverticulitis, you should adhere to a low-fiber diet until your condition stabilizes. Similarly, those with irritable bowel syndrome may want to limit fermentable fibers until they can manage their symptoms better. Fermentable fibers include inulin from asparagus, onions, and artichokes, as well as oligo-fructose found in bread, certain cereals, ripe bananas, and various vegetables.
Consult your GP or a registered dietitian for personalized advice. They may recommend following a low-FODMAP diet under professional supervision.
Those on prescribed medication should exercise caution when significantly increasing fiber intake, as some types, like pectin (found in fruit) and beta-glucans (from oats), may impact the absorption of certain medications, including aspirin. Additionally, individuals using insulin for diabetes management should be aware that fiber can lower blood sugar levels, possibly requiring medication adjustments. Always consult with your GP first.
How Much Fiber Should I Consume Daily?
According to UK guidelines, adults should aim for an average daily intake of 30g of fiber as part of a balanced diet. Unfortunately, many individuals do not meet this target. Excellent sources of fiber include fresh and dried fruits, vegetables, legumes, nuts, seeds, and whole grains.
For children, recommended daily fiber intake ranges from 15-25g, depending on age.
Signs of Excessive Fiber Intake
Rapidly increasing your fiber consumption can lead to uncomfortable side effects, including:
- bloating
- cramping and gas
- constipation
- diarrhea
These symptoms indicate that your digestive system is struggling. High fiber intake can also interfere with your appetite, making it harder to consume adequate nutrients such as proteins and fats. This can be particularly detrimental for those who exercise regularly, as insufficient caloric intake can impair performance. In severe cases, inadequate hydration along with high fiber consumption may result in bowel obstructions.
If you’ve been diagnosed with a digestive condition such as irritable bowel disease, irritable bowel syndrome, or Crohn’s disease, an increase in fiber may exacerbate your symptoms.
Signs of Insufficient Fiber Intake
Indicators that you may not be consuming enough fiber include:
- feeling hungry shortly after meals
- experiencing blood sugar fluctuations and fatigue following meals
- having cholesterol levels that exceed recommendations
- being overweight
- experiencing hormonal imbalances
- dealing with constipation and hemorrhoids
Prolonged low fiber consumption may lead to gut issues like diverticulitis or bowel cancer.
How to Gradually Increase Your Fiber Intake
If you’re planning to enhance your fiber consumption, it’s crucial to drink plenty of fluids, as this will help fiber function effectively in your digestive system. Make dietary changes gradually over several weeks rather than a few days, giving your body time to acclimate. As you progressively boost your fiber intake, your digestive system and gut bacteria will adapt, reducing the likelihood of unpleasant digestive symptoms.
If you’re on prescription medication or dealing with a gut issue such as diverticulitis or IBS, consult your GP or a registered dietitian for tailored advice.
Found this information helpful? Explore our resources:
High-fiber breakfast recipes
Understanding gut health
10 Probiotic Foods to Enhance Gut Health
Effective Ways to Improve Digestion
Top 10 Anti-inflammatory Foods
Have you tried fibermaxxing? What changes have you made? Share your experiences in the comments below.
This page was reviewed on 3 October 2025 by Kerry Torrens.
All health content on goodfood.com is intended for informational purposes only and should not be seen as a substitute for professional medical advice. If you have concerns regarding your health, consult your local healthcare provider. For more details, see our website’s terms and conditions.
