Article was written in cooperation with the Polish Diabetes Association, a member of the International Diabetes Federation.
Diet has always played a key role as a risk factor for chronic diseases. Since the second half of the 20th century, there have been major changes in the diet of Europeans. Traditional meals based largely on plants have been rapidly replaced by high-fat products with a significant animal content. A diet based on convenience foods and highly processed products can become monotonous. It is poor in fruit, vegetables and whole grain cereal products and, at the same time, there can be a lot of meals made up of meat dishes, fats, sugars and salt, i.e. foods that are high in energy density, low in nutritional value and low in fibre. What is fibre? It is a dietary fiber present in the cell walls of plants. Due to its specific properties, fiber is a compound that is resistant to the enzymes present in the human digestive tract. In the intestine, fiber slows the absorption of glucose, which results in a reduction in postprandial glycaemia and decreases insulin secretion. This is a mechanism that prevents overweight, obesity and promotes improved metabolic control in diabetes.
The 2022 clinical recommendations of the Polish Diabetes Association (PTD) for the management of diabetes emphasise that the minimum daily supply of fiber should be 25 g per day or 15 g for every 1000 calories from the diet. According to the PTD recommendations, the aim should be to increase fiber consumption by including at least 2 portions of whole grain cereal products and 3 portions of fiber-rich vegetables in the diet of a person with diabetes.
Due to its origin and specific properties, fiber can be divided into several types. Water-insoluble fiber, which, although it is not digested in the human digestive tract, has a number of important functions, including: stimulating chewing and saliva production, improving the flow of digestive juices and protecting against constipation, and reducing the energy value of the diet. It also makes the feeling of fullness last longer after meals, which is important for those concerned with maintaining a healthy body weight. Soluble fiber has the ability to produce a sticky, gel-like substance, so it reduces the absorption of cholesterol from the foods consumed and can therefore help lower serum triglyceride and LDL cholesterol levels. Beneficial effects on lowering cholesterol include pectin, wheat bran and oat bran. It has been proven that the intake of soluble fibre lowers glucose concentrations not only after a meal, but also on an empty stomach.
If it is not possible to supply the recommended amount of dietary fiber according to PTD recommendations, fiber supplements, especially in the form of water-soluble fractions, should be considered.
According to scientific studies and systematic reviews, the increase of daily fiber consumption by 8 g reduces the frequency of ischaemic heart disease, type 2 diabetes and colorectal cancer by 5-27%. The risk of stroke and breast cancer also decreases. Data suggest that consuming 25g to 29g of fiber each day may provide even greater health benefits. A meta-analysis that looked at 15 studies from 1,623 publications between 1980 and 2010 involving people with type 2 diabetes and a dietary intervention with increased fiber intake showed that in the above patients, increased dietary fiber can reduce fasting serum glucose and HbA1C (glycated haemoglobin) levels.
The production of natural, preservative-free and fiber-enriched foods has became more popular in recent years. The beneficial effects of such foods on health are also due to their content of biologically active substances with proven health-promoting effects: prebiotics, probiotics, polyunsaturated fatty acids and antioxidant vitamins. The range of such foods is already very wide and worth taking advantage of.
Polish Diabetes Association