1. How to quantitatively evaluate the nutritional value of protein?
A: The methods for evaluating the nutritional value of protein are:
A. The content of protein in food is the basis for evaluating the nutritional value of protein in food. Only when protein content is high and other indicators are good can we meet the needs of the body.
B, protein's digestibility (protein digestibility): The high digestibility indicates that protein is likely to be digested and utilized, and its nutritional value is also high.
Nitrogen intake-(fecal nitrogen-fecal nitrogen)
C. Biological value (BV) of protein: Its level mainly depends on the content and proportion of essential amino acids in food.
Nitrogen storage (absorbed nitrogen-(urine nitrogen-urine nitrogen)
D, Net utilization rate of protein: It indicates the utilization of protein in the body, including the digestion and utilization of protein, so it is more comprehensive.
Net utilization rate of protein = biological potency purple
F, protein efficacy ratio (PER)= grams of animal weight gain/grams of protein intake.
G, amino acid score (AAS) and amino acid score corrected by digestibility (PDCAAS)
Where protein is synthesized, the essential amino acids of protein must exist at the same time, and the lack of any one of them will affect the synthesis, so the composition of amino acids in food protein is used to evaluate protein.
2. What is amino acid score, and what is its nutritional significance?
Answer: Amino acid score: also called protein chemistry score. Protein's scoring model of essential amino acids in the tested food was compared with the recommended ideal model or the reference protein model. The amino acid with the lowest ratio is the first restricted amino acid, and the lowest ratio is the protein amino acid score or chemical score of the tested food. Its score is the ratio of essential amino acids in food protein to corresponding essential amino acids in reference protein or ideal model.
Amino acid score = AA content per gram of test protein (mg)/ AA content per gram of reference protein (mg)
The content of amino acids in food protein can be expressed by the relation of comparing reference protein or the relation of nitrogen content per gram. Therefore, amino acid score can reflect the relationship between protein composition and utilization rate. People of different ages have different amino acid scoring modes, and different foods have different amino acid scoring modes. Knowing the amino acid scoring model of each population and each food can help us to know the essential amino acids they lack respectively, so as to realize the amino acid complementation in a reasonable and complex diet, make the amino acid model closer to the needs of the human body, and improve the nutritional value of the mixed food protein.
3. What are the physiological significance of dietary fiber?
Answer: a, enhance intestinal function and facilitate fecal excretion;
B, control weight and lose weight;
C, can reduce blood sugar and blood cholesterol, that is, prevent and treat hyperlipidemia and diabetes;
D, preventing colon cancer;
E, prevention and treatment of diverticulosis, squeezing disease, gallstones.
4. What are the aspects of heat energy consumption?
A: The consumption of heat energy includes basal metabolism, labor consumption (physical activity) and the special dynamic function of food (food thermal effect).
5. What are the classification and main characteristics of vitamins?
A: There are many kinds of vitamins, which are usually divided into fat-soluble vitamins and water-soluble vitamins according to solubility.
Fat-soluble vitamins include a, d, e and K.
Water-soluble vitamins include B 1, B2, PP, B6, pantothenic acid, biotin, lipoic acid, folic acid, B 12, C and P.
* * * has the characteristics of vitamins:
A, it exists in natural food in its own form or in the form of precursors that can be used by the body;
B, most of them can't be synthesized in the body, nor can they be stored in tissues in large quantities, and they must be supplied by food frequently;
C, they are not raw materials for various tissues, nor provide energy;
D, although the daily physiological requirement is small, it plays a very important role in regulating substance metabolism;
F, often participate in the function of the enzyme in the form of coenzyme or auxiliary group;
Many vitamins have several compounds with similar structures and the same biological activities.
6. What are the factors that affect calcium absorption?
Answer: A. Absorption varies according to the amount of intake and the level of demand. When the food contains high calcium, the absorption rate decreases correspondingly, and when the body needs more calcium and consumes less, the absorption rate increases accordingly;
B, age, gender, physical condition. With the increase of age, the absorption rate decreases, male absorption rate is higher than female absorption rate, and female absorption rate increases during pregnancy;
C. factors that reduce calcium absorption in diet. Phytic acid and oxalic acid, dietary fiber, some alkaline drugs (gastric acid drugs), tetracycline and caffeine, 70-80% of which are not absorbed in the diet and excreted from feces;
D, factors that promote calcium absorption. Vitamin D, lactose, protein.
7. What are the manifestations of zinc deficiency?
A: When children are chronically deficient in zinc, the main manifestation is growth stagnation. In addition to growth stagnation, teenagers will also have delayed human maturity, hypoplasia of sexual organs, hypoplasia of secondary sexual characteristics and so on. If pregnant women are short of zinc, it can affect the growth and development of the fetus to varying degrees, leading to various malformations of the fetus. Zinc deficiency in children and adults can lead to loss of taste, loss of appetite and pica. In severe zinc deficiency, even if the liver has a certain amount of vitamin A reserve, the dark adaptation ability can be low. In acute zinc deficiency, the main manifestations are skin injury and alopecia, as well as diarrhea, depression and eye injury.
8. What are the main trace elements that the human body needs?
A: Iodine, iron, copper, zinc, manganese, cobalt, molybdenum, chromium, selenium and fluorine.
9. What are the main contents of community nutrition?
A: It includes not only natural science issues such as limiting the nutritional supply and nutritional status evaluation of various people in this area, but also social conditions and social factors that combine with natural science and restrict residents' nutrition, such as food structure, food economy, food culture, nutrition education, legal system and administrative intervention. Mainly from social life, focusing on the overall population of society, combining nutrition with social conditions and social factors to study and solve the nutritional problems of residents.
10. What are the main methods of dietary survey?
Answer: A, bookkeeping. Including the statistics of food consumption, the number of diners, the average food consumption per person per day, and the calculation of nutrient supply per person per day.
B. Review the query method. Including: 24-hour dietary review method, food frequency questionnaire survey method, dietary history method.
C. weighing method. Specific steps: 1. The main and auxiliary foods of each meal should be weighed before cooking; 2. Weigh the cooked food weight and the remaining cooked food weight (including the discarded residue weight) of the main and non-staple foods respectively and convert them into the net raw food weight of each meal; 3. According to the investigation days, calculate the average daily intake of various main and auxiliary foods per person; 4. According to the results, further calculate the percentage of dietary composition, heat energy and protein source in all kinds of foods, the percentage of heat production of three nutrients and the percentage of protein source to evaluate the rationality of dietary composition and heat distribution and the quality of protein in diet; 5. Investigation of food cooking methods; 6. Hygienic investigation of kitchens and canteens.
D. Chemical analysis methods
1 1. What are the nutritional characteristics of cereal?
Answer: It is the main source of dietary calories for China people (70%);
B, it is an important source of protein (about 8%);
C is an important source of B vitamins, and the germ contains vitamin E, but does not contain vitamin A, vitamin D and vitamin C;
D, it is a low-fat food (2%), and the fatty acid composition is mainly linoleic acid (60%);
E, chaff and germ are rich in inorganic salts (potassium, calcium, magnesium, phosphorus, iron and zinc);
12. What are the nutritional characteristics of milk and dairy products?
Answer: (1) Milk: A, the content of protein is 3-4%, and the digestibility is 87-89%. Its essential amino acid content and composition are similar to those of eggs, and its utilization rate is high. It belongs to high-quality protein, and the composition ratio of casein and albumin in milk is just the opposite to that in human milk. B, the fat content is 3-5%, the granules are small, and the digestion and absorption rate are high; C, the carbohydrate content is lactose (4-5%), which is lower than that of human milk, promoting the growth of lactic acid bacteria in the intestine and promoting the absorption of calcium and inorganic salts; D, it is a rich source of minerals, mainly calcium, phosphorus and potassium, but the iron content is insufficient; E contains all kinds of vitamins needed by human body, among which the contents of vitamin A and vitamin C are related to animal feed and seasons.
(2) dairy products: a. milk powder. Full-fat milk powder has good solubility, and has little influence on the properties of protein, the color and smell of milk and other nutrients. The fat content is about 26%, which is suitable for the general population. Skim milk powder is a kind of nutritious food with high protein and low fat, which is suitable for the elderly, obese and hyperlipidemia people. Formula milk powder properly adjusts and improves the nutritional components of milk to make it more suitable for infants, pregnant women and middle-aged and elderly people. B, yogurt. Keep all the nutrients in milk, and protein and fat become easier to digest; The utilization rate of calcium, phosphorus and iron is greatly improved; Lactic acid can inhibit the proliferation of intestinal bacteria, increase appetite and promote gastrointestinal peristalsis; Maintain the balance of intestinal flora, increase beneficial flora and inhibit spoilage bacteria. C. condensed milk. The sugar content is high (more than 40%), and the contents of protein, vitamins, inorganic salts and other nutrients are relatively low after being diluted with water, so it is not suitable for feeding infants and is suitable for long-distance travelers or field workers. D. cream It contains more than 80% of fat and less than 0/6% of water/kloc, and is mainly used as a table food and for making bread and cakes.
13. What should children pay attention to when cooking?
A: Early childhood is still a stage of rapid growth. According to the nutrition survey, children's intake of energy, protein, calcium, vitamin A, riboflavin and vitamin C is often low, and iron deficiency anemia, rickets, riboflavin deficiency, low weight and height are also common.
A, protein. Children should consume a certain amount of foods with high nutritional value in protein, such as milk, lean meat, poultry, fish, soybeans and bean products, and high-quality protein should account for more than 1/2 of the total protein in the diet.
B, in order to solve the shortage of minerals and vitamins, special emphasis should be placed on the diversity of dietary varieties. Especially eat more yellow-green vegetables and fresh fruits.
C, pure sugar and pure fat food should not eat more.
D, pay attention to cooking methods. It is necessary not only to keep the nutrients from being destroyed, but also to diversify the color, fragrance and shape of the diet to stimulate the appetite of young children.
E, diet should be timed, not picky eaters, not partial eclipse, and cultivate children's good eating habits.
14. What are the characteristics of maternal nutrition?
A: A: Energy. Pregnant women not only maintain their own energy, but also bear the energy needed for fetal growth and development and the growth of placenta and maternal tissue. The energy supply in early pregnancy is the same as that in non-pregnant women, and the energy supply in the middle and late pregnancy is increased by 200kcal per day on the basis of the energy supply in non-pregnant women.
B, protein. On the basis of non-pregnant women's protein supply, the daily increase of 15g in the second trimester and 25g in the third trimester. In addition, high-quality protein in the diet should account for more than 65,438+0/2 of the total in protein.
C. fat. There should be a proper amount of fat in the diet, including saturated fatty acids, n-3 and n-6 polyunsaturated fatty acids, to ensure the needs of the fetus and itself. However, pregnant women's blood lipids are higher than usual, and fat intake should not be too much. It is generally believed that fat provides 25-30% of the total energy.
Vitamin d, calcium, iron, zinc and iodine. Calcium almost all the calcium needed during pregnancy is accumulated in the fetus in the last three months to meet the needs of the growth and development of fetal bones and teeth. In addition, mothers need to store some calcium for lactation. Nutrition Society recommended the second trimester 1000mg/ day and the third trimester 1500mg/ day. Pregnant women should increase foods rich in calcium and supplement some calcium preparations when their dietary intake is insufficient. Iron, iron deficiency in early pregnancy is related to premature delivery and low birth weight. Iron deficiency during pregnancy will also affect the iron storage capacity of newborn liver, leading to iron deficiency or iron deficiency anemia earlier after birth. The iron supply for pregnant women recommended by China Nutrition Society is 28mg per day in the second and third trimesters. Zinc and maternal zinc supplementation can promote fetal growth and prevent congenital malformation. In the second and third stages of pregnancy, the recommended dietary zinc supply is 20 mg. Iodine is an essential nutrient for the synthesis of thyroxine, which can promote the synthesis of protein and the growth and development of the fetus, and is very important for the normal development of the brain. It is suggested that the daily supply of pregnant women should be 150 micrograms in the first trimester and 175 micrograms in the second trimester.
E. vitamins. Vitamin A deficiency in pregnant women is related to intrauterine growth retardation, low birth weight and premature delivery. Excessive vitamin A can lead to spontaneous abortion and congenital malformation (65,438+000 μ g retinol equivalent in the second and third trimester). Lack of vitamin D is related to osteomalacia in pregnant women, hypocalcemia in newborns and hand-foot convulsions. Due to the pregnancy reaction and metabolic changes in the first trimester, adequate water-soluble vitamins, vitamins B65, 438+0, B2, B6 and vitamin C should be supplemented.
15. What are the basic meals in the hospital?
A: Eat regularly. According to the pathological and physiological needs of different diseases, it is generally inconvenient to prepare various foods by changing cooking methods or changing food texture.
B, special treatment diet. It is a diet set by adjusting the nutritional components or production methods in the diet on the basis of the conventional diet.
C. experimental diet and metabolic diet for diagnosis. It is a special diet used for disease diagnosis or auxiliary examination or metabolic research.
16. What are the prevention and treatment principles of fatty liver?
A: A, control energy intake: generally 30-35 kcal/kg;
B, appropriately improve protein: suggest a high-protein diet (1.5-1.8g/kg);
C, reduce sugar and sweets;
D, control fat and cholesterol, the total amount of food and edible oil supplied throughout the day shall not exceed 40g, and the foods with high cholesterol shall be properly controlled;
E, supplement vitamins, minerals and dietary fiber.
17. What are the dietary principles for preventing and treating hypertension?
A. Quit smoking and drinking;
B, achieve and maintain the ideal weight or suitable weight, pay special attention to centripetal obesity;
C. limit the intake of sodium salt. For patients with mild hypertension or those with family history of hypertension, salt is 3-5g per day (equivalent to soy sauce15-25ml); Patients with moderate hypertension, daily 1-2g salt (equivalent to 5- 10 ml soy sauce); Patients with severe or rapid hypertension should adopt a salt-free diet;
D, increase potassium intake, and the ratio of K/Na is 2: 1.
E, reduce the intake of fat and cholesterol, fat accounts for less than 25% of total calories, and cholesterol is limited to less than 300mg per day;
F limit saturated fatty acids (S) and appropriately increase polyunsaturated fatty acids (P) to make the daily P/S value reach1-1.5;
G, appropriately increase the intake of magnesium, especially for patients who use diuretics such as uric acid and furosemide.
H. Edible foods rich in potassium and foods rich in calcium, vitamins and trace elements. Foods rich in high-quality protein, low in fat and cholesterol;
1. Prohibit or use less foods high in sodium, fat and cholesterol.
18. How to make nutrition and health education programs?
Answer: (1) Determine the educational target according to the educational purpose;
(2) determine the educational content;
(3) Deciding the methods and forms of education, developing leaders, cultivating backbones and mobilizing the masses; Carry out a variety of educational methods.
19. What are the main functions of carbohydrates?
Answer: a, provide energy;
B, an important substance that constitutes the human body;
C, transmitting information;
D, lubrication;
E. protecting protein from being digested by protease;
F. controlling the permeability of cell membrane;
G, save protein;
H, anti-ketogenic effect;
Me, detoxification.
20. What does the glycemic index mean?
Answer: The glycemic index refers to the area under the blood glucose response curve after 50g of test food is eaten on an empty stomach compared with the equivalent reference food (glucose or white bread), that is, the area under the response curve of the former is divided by the area under the curve of the latter and multiplied by 100%.
2 1. What are the physiological functions of fat?
A, supply and store energy;
B. forming a biofilm;
C. supplementing essential fatty acids;
D, carrying fat-soluble vitamins to promote their digestion and absorption;
E, increase the delicacy and satiety of food;
F, maintain body temperature and support various organs;
G, endocrine function.
8. What is the main function of vitamin C?
Answer: a, promote the formation of connective tissue;
B. anti-oxidation;
C, promoting the absorption of iron in food;
D, improve immune function;
E, anticancer effect.
22. What are the functions of vitamin E?
A: A, anti-oxidation;
B, maintain the integrity of red blood cells and promote the synthesis of red blood cells;
C, promoting the synthesis of coenzyme Q, and regulating the energy generated by protein, lipids and carbohydrates;
D, participate in DNA biosynthesis;
E, the impact on the eyes;
F, fight against environmental pollution;
G, anti-infertility effect;
H, the role of preserving vitamin a.
23. What are the physiological functions of minerals?
A:
24. What are the nutritional characteristics of eggs and egg products?
Answer: A, protein (13- 15%), concentrated in egg white, contains all the amino acids needed by the human body. The amino acid pattern is close to that of the human body, and the digestion and absorption rate is 98- 100%. It is one of the most ideal natural high-quality protein in food.
B, all the fat is concentrated in the yolk (11-kloc-0/5%), and the yolk has high cholesterol and rich lecithin;
C. egg yolk is rich in vitamins a and D.
25. What are the nutritional characteristics of school-age children?
A: A: Energy. Children grow vigorously, have high basal metabolic rate and are active, and need more energy, but energy intake should not be higher than energy consumption;
B, protein. Children's demand for electrical white matter increases with the degree of growth and development, especially muscle development;
C. minerals. Due to the rapid growth of bone and circulating blood volume, children need a lot of minerals, especially calcium, phosphorus and iron, and other trace elements such as iodine, zinc and copper must also be ingested in sufficient quantities.
Vitamin d Vitamins A and D are closely related to growth and development and must be fully supplemented. Thiamine, riboflavin and nicotinic acid are related to various metabolism in the body and must be fully supplied.
26. What are the aspects of evaluating the nutrition survey results?
A: After the dietary survey, according to the obtained table of per capita intake of various foods and food ingredients, the calculation is as follows: a. per capita daily intake of nutrients; B, the percentage of the average daily intake of various nutrients to the recommended appropriate intake; C, the percentage of energy distribution of three meals, recommended for adults = 30%: 40%: 30%, recommended for children = 25%: 35%:10%: 25%; D, the intake percentage of the three major energy nutrients, protein suggested 10- 14%, fat 20-30%, carbohydrate 60-70%; E, the percentage of protein sources. High-quality protein is not less than1/3 of the total intake; F, the ratio of calcium to phosphorus. Infant 2: 1, children and the elderly 1.5: 1, teenagers 1: 1, adults1:1.5; G, cholesterol intake; Different kinds of food intake. Then combined with the results of clinical nutrition examination and nutritional biochemical examination, a comprehensive evaluation was made.
27. What are the common causes of vitamin deficiency?
A: A, the supply is insufficient;
B, improper food storage and cooking methods;
C. malabsorption;
D, inhibiting the growth of intestinal bacteria;
E. increased demand;
28. What is the effect of malnutrition during pregnancy on mother and fetus?
A: Effects on the mother: A, malnutrition: nutritional anemia (iron, folic acid, VB2), osteomalacia (calcium, VD), dystrophic edema (protein, VB 1)b, pregnancy complications; C. Pregnancy-induced hypertension syndrome (maternal obesity, high sodium intake, insufficient intake of protein, calcium, zinc, magnesium and VB6).
Effects on fetus: a. Low birth weight (low pre-pregnancy weight, slow weight gain during pregnancy, low plasma total protein and albumin of pregnant women, anemia of pregnant women, lack of VA, VB 1, VB2, heavy drinking or smoking of pregnant women, premature delivery). B. Premature infants and infants younger than gestational age; C, perinatal neonatal mortality increased; D, brain development is impaired (protein); E, congenital malformation: (zinc, iodine, folic acid deficiency, too much VA).
29. What are the main principles of food fortification?
A: 1987, the codex alimentarius commission made regulations on adding essential nutrients to food. The basic principles that need to be strengthened are: compensation for losses (recovery) in the process of food processing, storage and treatment; Ensure the nutritional balance of food imitations or substitutes; Compensation (standardization) for changes in nutritional components caused by natural causes; Improve the nutritional content of food itself (fortification); Provide a balanced intake of micronutrients (formula food) under special circumstances.