According to the Health Insurance Review and Assessment Service, approximately 1.3 million patients visited hospitals for sleep disorders in 2023. As the number of people struggling with sleep increases, the impact of pre-bedtime eating habits on sleep quality is drawing attention. Experts point out that evening dietary habits are one of the key factors determining quality sleep.
Jillian Kubala, a registered dietitian in the United States, presented six foods to avoid before bedtime through the health media outlet "Health." She said, "Certain foods can affect not only the process of falling asleep but also the depth and duration of sleep."
Caffeinated foods and beverages are cited as typical sleep disruptors. Caffeine stimulates the central nervous system to heighten alertness and blocks the action of adenosine, a neurotransmitter that induces drowsiness. This includes not only coffee but also energy drinks, matcha desserts, and dark chocolate. The effects are greater for those who are sensitive to caffeine.
Foods high in added sugar have similar effects. Soft drinks, snacks, and candy rapidly raise blood sugar levels and then cause them to drop quickly, stimulating the secretion of cortisol and adrenaline. While they may induce temporary drowsiness right before sleep, the subsequent blood sugar crash causes people to wake up during the night.
Refined carbohydrates also interfere with sleep. Foods made with refined flour, such as white bread, cause rapid fluctuations in blood sugar and insulin levels, hindering deep sleep. A study published in the journal "Frontiers in Nutrition" found that higher intake of refined carbohydrates and sugar is more likely associated with lower sleep quality.
Spicy foods are particularly risky for those with acid reflux symptoms. In a lying position, esophageal irritation can worsen, disrupting sleep through discomfort. Ingredients such as chili peppers raise body temperature, negatively affecting the sleep environment.
Ultra-processed foods and alcohol also reduce sleep quality. According to the "Journal of Nutrition," people with lower sleep quality tend to consume more fast food and instant foods. Ultra-processed foods are high in refined carbohydrates, sugar, and saturated fats, and are linked to sleep disorders and shorter sleep duration. Alcohol initially induces drowsiness, but over time it disrupts the sleep cycle and causes mid-sleep awakenings. A study by the University of Cambridge in the UK found that higher alcohol consumption is associated with shorter sleep duration, lower sleep quality, and increased risk of insomnia.
