Fibres are part of the large group of carbohydrates, but they have a better reputation than refined carbohydrates and sugars, which are (justly) receiving such negative publicity nowadays. A high intake of fibres or whole-grain are in fact often associated with a healthier Lifestyle.
Fibres are known to reduce risk of cardiovascular disease and diabetes 2, oxidation of fats, inflammation (increased, instead, by a consumption of refined carbohydrates), diverticulitis and to improve constipation. In contrast, easily digested refined carbohydrates found in white bread, white rice, pastries, sugared sodas and other highly processed foods lead not only to weight gain but promote diabetes and heart disease.
But not only…..
Fibres are found in vegetables, fruit, seeds, legumes as well as in whole grains.
There are two main types of fibers: soluble fibers that dissolve in water, bind to fatty substances in the intestines and carry them out as waste, thus helping in lowering cholesterol; and insoluble fibers, that do not dissolve in water and help push food through the intestinal tract, promoting regularity.
But there’s more.
When we ingest food containing a particular kind of insoluble fibres, the ‘resistant starches’, a message to the brain is sent that tells us to stop eating. Resistant starches are so called because they cannot be broken down by the enzymes in our small intestine. It is the bacteria that reside in this part of the gut that finally digest this food and release a special type of short-chain fatty acids that trigger the fullness switch that saves us from overeating. The message is sent from the gut to the brain by the satiety hormones glucagon-like peptide1, which also delays the absorption of carbohydrates, and pancreatic peptide, both secreted by the intestinal cells and giving a feeling of satiation and fullness. All foods have this ability at different levels, but fibres are second only to proteins in their satiating effect. Conversely, only alcohol, when consumed in moderate amounts, stimulates the appetite.
Resistant starches occur naturally in peas, beans and lentils. Proteins, contained in such plant food, as well as their fibres content, are the most filling of food items. So, eating legumes (pulses) will help with constipation and diverticulitis, as well as in keeping your blood sugar levels down, lowering your cholesterol, controlling inflammation (port of entry to many diseases including cancer) and helping you eat less!
Gogebakan O, Kohl A, Osterhoff MA, van Baak MA, Jebb SA, Papadaki A, Martinez JA, Handjieva-Darlenska T, Hlavaty P, Weickert MO, et al. 2011. Effects of weight loss and long-term weight maintenance with diets varying in protein and glycemic index on cardiovascular risk factors: the diet, obesity, and genes (DiOGenes) study: a randomized, controlled trial. Circulation, 124:2829–38)
Ebbeling CB, SwainJF,Feldman HA, Wong WW, Hachey DL, Garcia-Lago E, Ludwig DS. Effects of dietary composition on energy expenditure during weight-loss maintenance. JAMA 2012; 307:2627–34
Wilson C., 2015. Get stuffed: Super-filling food satisfies your hunger for longer, The New Scientist, 7 June
Coghlan, A. 2014. Bacterial waste makes you feel fuller for longer, The New Scientist, 16:19 12 December 2014
Wikipedia, 2015. Peptide YY, in : https://en.wikipedia.org/wiki/Peptide_YY
Wikipedia, 2015, Glucagon-like peptide-1, in: https://en.wikipedia.org/wiki/Glucagon-like_peptide-1