The nutrition needed in a day should be spread evenly over three meals. The calories taken in each meal should account for about 1/3 of the total calories for the whole day, but lunch can be more to supplement the calories consumed in the morning, but also to provide energy for work and study in the afternoon. Therefore, the calories of three meals a day, breakfast should account for 25%-30%, lunch accounts for 40%, and dinner accounts for 30%-35%.

A, 1, a day to eat three meals people eat not just to fill the stomach or craving, mainly to ensure the normal development of the body and health. Experimental evidence: three meals a day, food protein digestion and absorption rate of 85%;

2, such as the change to two meals a day, each meal ate half of the amount of food throughout the day, the protein digestion and absorption rate of only 75%. Therefore, according to the living habits of our people, generally speaking, three meals a day is still reasonable.

3, but also note that the time between meals should be appropriate, the interval is too long will cause a high degree of hunger, affecting people's labor and work efficiency; interval if too short, the last food in the stomach has not been emptied, then eat the next food, will make the digestive organs do not have a proper rest, digestive function will gradually reduce, affecting the appetite and digestion

4, the general mixed Food stays in the stomach for about 4 to 5 hours, and the interval between meals is 4 to 5 hours, or 5 to 6 hours, which is basically in line with the requirements.

Second, the reference index

In recent years, the Chinese Nutrition Society has introduced the Dietary Reference Intakes (DRIs), which contain a number of reference values (EAR, RNI, Al, UL), which need to be correctly selected according to the purpose of the use of the appropriate index.

1. Average Requirement (EAR): It is the average value of the requirement of a nutrient in a particular group of gender, age and physiological condition. Dietary intake of nutrients to reach the EAR level can meet the needs of 50% of the individuals in the group.

2. Recommended Nutrient Intake (RNI): The RNI can meet the needs of the vast majority (97%-98%) of individuals in a particular gender, age and physiological condition group. Long-term intake of RNI levels can maintain appropriate reserves in tissues.

3, appropriate intake (AI): is through observation or experimentally obtained by the healthy population of a certain nutrient intake, such as exclusive breastfeeding full-term birth of healthy infants, from birth to 4-6 months, all of its nutrients from breast milk, so the amount of nutrients intake of breast milk that is the infant's AI. with the difference between the RNI is that the accuracy is not as good as the RNI, may be higher than the RNI.

4, tolerable maximum level of intake of RNI, can maintain appropriate reserves in the organization. p>4, tolerable maximum intake (UL): is the average daily maximum intake of a nutrient. This amount is not detrimental to the health of almost all individuals in the general population.