Plant food structure and lipid digestibility
Résumé
Lipid intakes, especially saturated fats, are, in many developed countries such as the UK, above the current recommendations (total fat intake should be <35% of the total energy intake). Although lipids are essential nutrients, an overconsumption of fats can lead to hyperlipidaemia, elevated levels of lipids and cholesterol in the blood, which is an important risk factor for atherosclerosis and therefore cardiovascular disease (CVD). However, not all the lipids contained in certain foods, in particular plant-based foods, are available for digestion. Therefore, there is a discrepancy between the nutritional composition and the actual lipid absorbed and metabolised. Lipids are a major form of carbon storage in many plant species, and they are predominantly found in the grains and seeds of plants in the form of lipid or oil bodies. Based on the properties of plant-based foods, specifically their structure and the physicochemical properties of their constituents, several processes can affect lipid digestibility. Especially, the macro- and microstructure of the food influences how it is digested, broken down and releases its nutrients and subsequently their absorption in the upper gastrointestinal tract.