Food Matrix

Are All Calories the Same?  This is a question I've often been asked as a dietitian.  Technically the answer is yes, since a calorie is a unit of energy, a system of measurement devised in the 19th century.  The results of how much the combustion of a food raises the temperature of water is still used to determine the calories indicated on a food label,  However, according to nutritional scientist Sarah Berry, the calories we see on a food label do not indicate the calories absorbed by your body since the food’s matrix determines how the nutrients in a food are absorbed.  For example, the fibrous walls containing the fat of whole almonds are not easily digested by us.  But they are a feast for our gut microbes that use them and then cause us to excrete their remains.  Dr. Berry’s research indicates that we absorb only about 70% of the calories indicated on the food label of whole almonds  The food matrix consists of a number of factors that can change the absorption of the calories listed on the label.  Fiber is an important component in decreasing absorption and feeding our microbiome.  Additionally, other nutritional components can contribute to the food’s matrix, changing the absorption of calories   So focusing on calories or a single nutrient misses the big picture.  And not surprisingly, whole foods generally have a more complex and healthier matrix than ones that are ultra processed.