Constipation is a highly prevalent and difficult-to-cure health problem, forcing 10–20% of the worldwide population to seek medical care. Efficacy of treatments varies greatly among individuals, and problems are becoming more frequent despite higher consumption of fibre-rich foods, the most popular solution for preventing such gastrointestinal disorders. The evidence that consumption of fibre prevents and relieves constipation is unconvincing or uncertain. The food industry has made great efforts to develop fibre-rich ingredients, especially those from food by-products and wastes. Except for psyllium and wheat bran, most of these ingredients have intermediate or low laxative potential and their efficacy needs to be confirmed by more clinical studies. This review suggests that there are major discrepancies between the proposed fibre-enriched ingredients and the consumers' needs. As a lasting solution to prevent constipation, the true impact of dietary fibre and potent food-grade laxatives might also be limited by overeating.