Eduqas GCSE Food Preparation and Nutrition: Student Book

16 Dietary fibre Dietary fibre is also referred to as roughage, cellulose and non starch polysaccharide (NSP) . Fibre is a type of carbohydrate that is found in plant-based foods, including fruit, vegetables and whole and unprocessed grains. Dietary fibre mostly refers to insoluble fibre , meaning that it is not easily broken down by the digestive system and most of it passes through the body unchanged. This fibre helps to keep healthy bowels and prevent digestive problems such as constipation and haemorrhoids (piles). Soluble fibre is broken down by bacteria in the large bowel and can then be digested. This fibre may help to reduce the amount of cholesterol in the blood which can guard against coronary heart disease (CHD) . Oats are often recommended in a cholesterol-lowering diet because they contain a soluble fibre called oat beta-glucan . Pectin is another formof soluble fibre. It is a complex carbohydrate, which is found both in the cell walls of plants such as apple, plums, pears and citrus fruits peel. It is used as a setting agent in jams and jellies. Why we need dietary fibre in the diet Fibre is important to keep your bowels healthy. When fibre passes through your bowels, it absorbs lots of water and increases the bulk of any waste material that leaves your body. This makes your stool (poo) softer and easier to pass. A diet high in fibre will prevent constipation, haemorrhoids and diverticulitis (when the bowel wall becomes inflamed and damaged). It can also help to prevent type 2 diabetes, some cancers (such as cancer of the colon) and is believed to lower the risk of coronary heart disease. When you eat foods which are high in fibre, you feel fuller for longer. This can reduce the temptation to snack in between meals and can help people maintain a healthy weight. It also slows down the absorption of carbohydrates in the blood, which helps to keep blood sugar levels constant. This can be useful for those who have diabetes. When a diet is too low in fibre it is often as a result of eating refined foods, for example eating white bread instead of wholemeal bread or white rice instead of brown rice. It also means a general lack of fruit and vegetables in the diet. This can lead to a variety of conditions, such as constipation, haemorrhoids, diverticulitis and certain cancers. Of course it is possible to eat too much fibre, which would leave you feeling bloated with stomach cramps, flatulence and in extreme cases diarrhoea. Too much fibre can also affect mineral absorption and your body may not take in vital minerals such as iron and calcium. Phytic acid is present in wheat, and too much causes phytates of calcium and iron to form, depriving the body of both these minerals. Key point Dietary fibre can be either insoluble or soluble. Soluble fibre helps to lower blood cholesterol. All of these foods are good sources of fibre - how many do you eat regularly? Diverticula Intestines Bleeding Inflamation Diverticulitis Diverticulosis Colon DIVERTICULOSIS and DIVERTICULITIS Diverticula CORE KNOWLEDGE