Caloric restriction equates to energy restriction which leads to side effects such as an inability to concentrate and fatigue. In addition, severe restriction can decrease your metabolism and lead to a loss in muscle mass, which further lowers your metabolism and reduces your physical strength and durability. Your body requires energy for essential biological processes including hormone regulation, meaning significant energy deprivation can lead to hormone-related problems such as loss of fertility and weaker bones.
More important than quantity is the quality of calories consumed. For a healthy diet and sustainable weight loss, you should focus on eating a sufficient amount of good quality calories rather than a restricted amount of poor quality calories. Good quality calories comprise natural and primarily plant-based whole foods such as fruits, vegetables, beans, grains and legumes while poor quality calories comprise highly processed foods such as products based on white flour as well as foods that are high in refined sugars.
Although all calories are equal in energy, they do not all have the same effects in your body. Eating 100 calories of vegetables will have very different effects to eating 100 calories of sweets. Different foods have varying compositions of nutrients causing them to be processed in different ways. Your body has developed a variety of biochemical pathways to metabolise the diverse range of foods in your diet. These pathways differ in efficiency, with some resulting in more energy loss via heat than others. Moreover, the varying nutrient compositions of foods impact your hormone levels differently, causing altered responses in appetite regulation.
The Glycemic index, which defines the extent to which a food raises your blood sugar levels, shows that refined carbohydrates are less satiating than unprocessed whole foods. This is due to the low fibre content of refined carbohydrates resulting in their fast absorption and subsequent spikes in blood sugar levels. On the other hand, unprocessed carbohydrates are digested slowly resulting in more stable blood sugar levels and increased satiety.
To increase your metabolism for a more sustainable approach to healthy weight management or weight loss, ensure that most of your calories come from high-protein whole foods. Whole foods require more energy to digest than processed foods, are more satiating and higher in nutritional value. While carbohydrates and fats should still be included in a healthy diet, protein requires more energy to metabolise which means that increasing the proportion of protein in your diet can result in weight loss. Protein is also believed to be the most satiating macronutrient, allowing it to help regulate your appetite.
The truth is that calories cannot be counted. While calories do define the amount of energy a food contains, they do not portray how much energy you will gain from the food, as every food is metabolised differently. Rather than focusing on restricting your body of energy, focus on nourishing it with the nutrients it needs to establish a healthy weight. Whether your goal is weight loss, weight gain or simply weight maintenance, consuming a sufficient number of calories for healthy energy and nutrient intake is crucial.
+ Words: Yasmin Razzaque
Yasmin Razzaque is a Biochemistry graduate with a keen interest in health and nutrition. She uses her scientific knowledge and ability to critically analyse research to write articles about healthy and sustainable eating and wellbeing.