The average adult stomach has a capacity of around 500mL and can expand to fit one litre of food. When our stomach is full, signals are sent to our brain to trigger feelings of satiety leaving us feeling full and satisfied. Some foods such as ice-cream might contain our entire average daily calorie intake of 2000 Cal in 1 litre of food product, whereas we would have to eat around 44 cups of strawberries (11 litres) to attain the same calorie count. Moreover, strawberries would provide additional benefits from essential nutrients like vitamin C and fibre, compared to calorie-dense foods such as ice-cream.
Traditional weight-loss diets often focus on reducing portion size and eating less, but evidence suggests that adherence to these diets is poor owing to people feeling constantly hungry and unsatisfied. Evidence suggests it might be more effective to eat foods with low calorie density in order to increase satiety and satisfaction. In fact, studies have shown that eating an unrestricted diet of whole food plant-based products can lead to greater weight loss and higher adherence rates. These benefits are likely at least in part due to such a diet being low in calorie-dense food products.
Greger, M. (2020). A Whole Food Plant-Based Diet Is Effective for Weight Loss: The Evidence. American Journal of Lifestyle Medicine, 1