Fibre supplements and fibre from foods

Fibre is an important dietary component for a healthy body and reduce the risk of disease. Coronary artery disease, diabetes, bowel disease and obesity can all be helped by adequate fibre intake in the diet. Fibre plays a significant role in the health of the digestive system and regular bowel function. But what is fibre?

Fibre is described as the part of plant food which cannot be completely broken down by enzymes during the digestive process. This means the fibrous components of foods travel through the digestive system without being absorbed. Common sources of fibre foods include fruit, vegetables, beans, seed, nuts and wholegrains.

All fibres are not equal

How fibre negotiates its way through the digestive track depends on the particle size, solubility, hydration properties and viscosity, with certain fibres being better choices for particular health conditions. Fibre comes in three basic forms - soluble, insoluble and resistant starch.

Soluble fibre

Soluble fibre includes pectin’s, gums and mucilages. It helps to lower cholesterol and stabilise blood sugar, slows stomach emptying and helps with satiety (feeling full). Food sources - fruit, vegetables, oats, barley and legumes. Supplement sources – beta-glucan, psyllium fibre (ispaghula husk), slippery elm, wheat dextrin, inulin and guar gum.

• Slippery elm is a mucilage soluble fibre which can sooth the digestive system when irritated and calm an acidic stomach commonly associated with reflux. 
• Psyllium is a common ingredient in many fibre supplements or found by itself and easily added to foods to boost fibre content. 
• Beta-glucan is usually derived from oat and is found in cholesterol lowering supplements. 
• Inulin provides food for growth of beneficial intestinal bacteria providing support for a healthy colon and digestive system. 

Insoluble fibre

Insoluble fibre includes cellulose, hemicelluloses and lignin.This type of fibre attracts water and helps with bowel regularity and blood sugar control. Insoluble fibre is not fermented by gut bacteria and is less likely to cause flatulence and bloating. Food sources – whole grain and bran (bread and cereals), nuts and seeds and the skin of vegetables and fruits. Supplemental sources - Sterculia (derived from the Sterculia urens tree), linseeds and chia seeds.

Resistant starch

Resistant starch is a polysaccharide (carbohydrate) and a part of most of the foods eaten in the diet. Resistant starch is not easily absorbed in the digestive system. Starch ferments in the bowel helping to keep the bowel functioning efficiently, blood sugar control, insulin sensitivity and satiety. Food sources – undercooked pasta; raw or cool, cooked potatoes (think potato salad), legumes, lentils, un-ripened bananas, cashews, uncooked oats.

Are you consuming enough fibre?

Recent research (May 2018), has concluded most Australian’s are not eating enough fibre in their diet. Those most noted for the shortfall were adolescents, young adults, males, people from lower socio-economic status and those with lower dietary intake. The fact is – chronic diseases are linked to low-fibre intake, encouraging all people to increase the level of fibre in the diet can help lower the incidences of chronic disease in Australia and the burden on health.

Cardiovascular disease (CVD)

Health benefits of dietary fibre intake on lowering the risk of cardiac disease include:

• Improved lipid profile – triglycerides and LDL reduction
• Blood pressure – reduced
• Diabetes, insulin resistance – improved insulin sensitivity
• Lowered risk of mortality from CVD

Over-weight and Obesity

Supplementing with soluble fibre for people who are struggling with weight issues can improve body proportion (weight-loss) and metabolic outcomes – such as risk for developing cardiovascular disease and diabetes.

Soluble fibre intake can provide improvement in:

• central obesity (weight around the waist)
• high blood pressure
• high blood sugar
• high blood triglycerides

Satiety (feeling satisfied)

Successful weight-loss is often achieved when satiety is reached. This can be obtained by including fibre-rich foods or fibre supplements in the diet. The intake of fibre delays hunger and slows gastric emptying and motility.

Fermentation of fibre in the gut 

Fibre undergoes partial fermentation by gut bacteria, turning it into short chain fatty acids (mainly acetate, propionate and butyrate), a source of energy and promoting satiety by slowing intestinal transit time.

Functional Bowel Disorders (FBD)

These include constipation; irritable bowel syndrome (IBS; Inflammatory Bowel Disease (IBD) – ulcerative colitis and Crohn’s disease are a group of bowel disorders with often complicated etiology and resolution where no one particular treatment will alleviate symptoms for all people. Studies have revealed a definite improvement when fibre is consumed with bowel disorders such as functional constipation and IBS.

Psyllium is soluble, viscose, fermentable fibre which provides bulk and mucilage promoting passage through the bowel and alleviating constipation. Fermentation by microbiota can improve the microbiota itself, supporting digestive epithelium and immune cells.

Other conditions

Other conditions which have shown improvement by an increase of fibre in the diet:

Seborrheic dermatitis – improved with the intake of fruit, thought due to the prebiotic effect of fruit (esp. pectin) on the microbiota. Pectin is a fibre found in apples, plums, peaches, oranges and apricots.

Asthma – intake of whole fruit has shown to reduce the severity of asthma in both adults and children, though promoting a healthier bowel microbiome which actively suppresses inflammation of the airways.

Chronic Obstructive Pulmonary Disease (COPD) – Fruit intake promotes healthy lung immune function. This is  through the bowel microbiota connection with liver and lung, affection inflammatory immune mediators.

Bone Mineral Density – Diets rich in fibre support the absorption of calcium, inhibit reabsorption of osteoclasts (bone breakdown), and promote osteoblast activity (bone formation.

Fibre Rich Diet

Fruit (whole) - apples, pears, strawberries, raspberries, avocado and bananas and really all fruit

Vegetables – broccoli, carrots, tomato, brussel sprouts, kale, spinach and literally all vegetables

Legumes – lentils, kidney beans, chickpeas and split peas

Grains – oats, quinoa and pretty much any whole grains

Nuts and Seeds – almonds, walnuts, pistachio, chia seeds, flaxseeds, sun flower, pumpkin seeds and yes, all nuts and seeds
contain good amounts of fibre.

Whole grain breads, pastas, rice, crackers and cereals

Note: Drink plenty of water and introduce fibre slowly to avoid side effects such as flatulence and cramping.

In summary

Fibre from dietary foods or supplements sources can help support:

• Digestive health and healthy regular bowel function
• Removal of toxins
• Cardiovascular health by lowering cholesterol
• Healthy blood sugar levels
• Provide appetite control

References

1. http://www.nutritionaustralia.org/national/resource/fibre
2. http://www.nutritionaustralia.org/national/frequently-asked-questions/general-nutrition/nuts-and-health
3. Dietary fibre intake and mortality from cardiovascular disease and all cancers: A meta-analysis of prospective cohort studies. https://www.ncbi.nlm.nih.gov/pubmed/26711548
4. Cereal fibre intake and risk of mortality from all causes, CVD, cancer and inflammatory diseases: a systematic review and meta-analysis of prospective cohort studies. https://www.ncbi.nlm.nih.gov/pubmed/27193606
5. Effects of isolated soluble fiber supplementation on body weight, glycemia, and insulinemia in adults with overweight and obesity: a systematic review and meta-analysis of randomized controlled trials. https://www.ncbi.nlm.nih.gov/pubmed/29092878
6. Understanding the impact of chia seed mucilage on human gut microbiota by using the dynamic gastrointestinal model simgi®
7. Chia oil supplementation changes body composition and activates insulin signaling cascade in skeletal muscle tissue of obese animals https://onlinelibrary.wiley.com/doi/full/10.1111/j.1467-3010.2005.00481.x
8. A paradigm shift for the prevention and treatment of individual and global obesity https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6276910/
9. Probiotics, fibre and herbal medicinal products for functional and inflammatory bowel disorders. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5429330/
10. Pectin and Pectin-Based Composite Materials: Beyond Food Texture https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6017442/
11. https://www.benefiber.com/fiber-supplement-products/
12. https://www.healthdirect.gov.au/high-fibre-foods-and-diet
13. Dietary Fibre Intake in Australia. Paper I: Associations with Demographic, Socio-Economic, and Anthropometric Factors https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5986479/