(1) The food should be comprehensive: keep diversified and don't be partial to food. You should eat whole grains, eggs and milk of livestock and poultry, aquatic vegetables, dried and fresh fruits, fish and shellfish, shrimps and crabs, and delicacies. Don't "talk about color change" just because you have high blood pressure and coronary heart disease. Old people with these two diseases can eat lean meat and milk, and eat more beans. Otherwise, you will lose weight and resistance due to malnutrition, which is not good for your health.
(2) Diet should be light: As the taste of the elderly declines, they especially like to eat greasy, greasy and fried foods, but these foods are not easy to digest and should be controlled. Chinese medicine believes that eating too much fat and sweets is easy to help damp and produce phlegm, and even turn heat into poison, so a "light diet" should be given priority to. Taking grains as nourishment, fruits and vegetables as filling and meat as benefit can not only meet the supply of various nutrients, but also keep the stool unobstructed. But being light doesn't mean being vegetarian.
(3) Moderate diet: The elderly have poor gastrointestinal adaptability and should avoid overeating. Overeating can cause dysfunction of transportation, stagnation of qi and blood, food corruption, leading to abdominal distension, diarrhea, belching and other symptoms, and even death due to acute gastric dilatation or induced myocardial infarction. There was an old man, 152, who died of overeating. His body was dissected by Harvey, a famous anatomical physiologist, and it was found that the aging phenomenon of his organs was not obvious, and he would not die without overeating.
(4) Food should be soft and rotten: the chewing ability of the elderly is reduced due to worn, loose or falling teeth, and the secretion of various digestive enzymes is reduced. Therefore, food should be chopped and cooked, meat can be made into minced meat, and vegetables should be made into tender leaves. Cooking methods such as stewing, stewing, steaming and steaming. It is mostly used for frying greasy foods and spicy condiments, and is rarely used. At the same time, we should also pay attention to the collocation of meat and vegetables, lean collocation, good color and fragrance, in order to stimulate appetite and promote digestion.
(5) Eat less and eat more: the liver of the elderly has reduced ability to synthesize glycogen, less glycogen reserves, poor tolerance to hypoglycemia, and is prone to hunger and dizziness. Therefore, before going to bed, after getting up or between meals, the elderly can eat a little food as a snack. Generally, you can arrange five meals a day, and the amount of each meal should not be too much. Don't eat snacks, especially sweets, between meals, so as not to affect your appetite and lead to digestive disorders.
(6) The temperature should be appropriate: because the saliva secretion of the elderly is reduced, the oral mucosal resistance is reduced, and it is not appropriate to eat overheated food. It is considered that overheating of diet is one of the causes of esophageal cancer. On the contrary, eating too cold is easy to damage stomach qi. The so-called "cold hurts the spleen, and hard things are hard to melt" is reasonable.
(7) Food should be fresh: rotten fish food, rotten fruit, rancid oil, moldy peanuts, cereal beans, overnight leftovers, etc. It should not be eaten to avoid food poisoning or cancer.
(8) Eat more fruits and vegetables: The elderly should eat more fresh fruits and vegetables to ensure the supply of vitamins and minerals. Pectin and cellulose can promote gastrointestinal peristalsis, prevent feces from staying in the intestine, and play an important role in preventing constipation and intestinal tumors. At the same time, the elderly eat marine plant foods such as kelp and laver, which has a certain effect on preventing arteriosclerosis and reducing accidents caused by cerebrovascular diseases.
(9) Sufficient water: For the elderly, we often cook some dishes such as soup, soup and puree, which not only supplements water, but also helps digestion. With the increase of age, the physiological functions of various organs of the human body will decline to varying degrees, especially the digestive and metabolic functions, which will directly affect the nutritional status of the human body, such as tooth loss, decreased secretion of digestive juice, and slow gastrointestinal peristalsis, thus reducing the absorption and utilization of nutrients in the body. How to strengthen the health care for the elderly, delay the aging process, prevent and treat various common diseases of the elderly, and achieve the purpose of health and longevity and improve the quality of life has become an important topic of medical research. The nutrition of the elderly is an extremely important part. Reasonable nutrition helps to delay aging, while malnutrition or overnutrition and disorder may accelerate the aging process. Therefore, it is very important to explore the mechanism and physiological changes of aging from the perspective of nutrition, and to study the nutritional needs and reasonable diet in old age.
Physiological and metabolic characteristics of the elderly
1, metabolic function decreased.
First, basal metabolism is reduced. It is about 15% ~ 20% lower than that of middle-aged people. This is related to the slowing down of metabolic rate and the reduction of metabolic quantity. Second, anabolism decreases and catabolism increases. The imbalance of synthesis and catabolism leads to the decline of cell function.
2. Changes in body composition
Adipose tissue in the body increases with age, while lean body mass decreases with age, which is manifested in three aspects:
First, the number of cells decreases. The outstanding performance is that the weight of muscle tissue decreases and muscle atrophy occurs.
Second, the water in the body is reduced. Mainly used in intracellular fluid.
Third, the minerals in bone tissue are reduced. In particular, the decrease of calcium leads to the decrease of bone mineral density. Bone mineral density refers to the weight of bone tissue per unit volume or unit area. Normal people can still increase bone mass in adulthood, reaching a peak at the age of 30-35, and then gradually decreasing, and decreasing by 20%-30% at the age of 70. Therefore, the elderly are prone to different degrees of osteoporosis and fractures.
3. Changes in organ function
The first is the digestive system. The secretion of digestive juice, digestive enzymes and gastric acid decreases, which affects the digestion and absorption of food. Stomach distensibility is weakened, intestinal peristalsis and emptying speed are slowed down, and constipation is easy to occur. Most of the teeth of the elderly fall off, which affects the chewing and digestion of food.
Second, the heart function is reduced. Heart rate slows down, cardiac output decreases, and blood vessels gradually harden.
Third, brain function, renal function and liver metabolic capacity all decrease with age. Compared with young people, the number of brain cells and kidney cells is greatly reduced, the regeneration ability of nephron is reduced, the glomerular filtration rate is reduced, and the glucose tolerance is reduced.
Nutritional needs of the elderly
1, protein
In the elderly, catabolism increases, while anabolism decreases. Therefore, the elderly should eat more foods rich in protein, at least as much as adults, with a daily protein of 1.0 ~ 1.2g, which can be appropriately reduced after 70 years old. Protein will produce some toxic substances after metabolism, and the liver and kidney functions of the elderly have been weakened, so the ability to remove these toxic substances is poor. If protein eats too much, the toxic products after metabolism will not be discharged in time, but will affect his health. Generally speaking, the intake of protein in the elderly should account for 10% ~ 15% of the total dietary calories.
2. Fat
It should account for 15% of the total diet, in which saturated fatty acids account for 0 ~ 10% and unsaturated fatty acids account for 3 ~ 7%. The secretion of pancreatic lipase in the elderly is reduced, and the ability to digest fat is weakened. We should eat less fat and eat some vegetable oil in moderation.
3. Heat energy
As basal metabolism decreases, physical activity decreases, the proportion of adipose tissue in the body increases, and the demand for heat energy in old age decreases relatively, so the daily total heat energy intake should be reduced appropriately to avoid excess heat energy being converted into fat storage and causing obesity. The intake of heat energy should gradually decrease with the increase of age. After 6 1 year, it will be reduced by 20% compared with youth, and it will be reduced by 30% after 70 years old. Generally speaking, the daily intake of heat energy is 6.72 ~ 8.4 MJ (1600 ~ 2000 kcal), and the daily intake of heat energy for people weighing 55kg is only 5.88 ~ 7.65 MJ (1400 ~1800 kcal).
4. sugar
Due to impaired glucose tolerance, decreased insulin secretion, weakened blood sugar regulation ability and easy increase of blood sugar in the elderly. It has been reported that the intake of sucrose may be related to the onset of cardiovascular diseases such as atherosclerosis and diabetes, so the elderly should not eat foods containing high sucrose; Too much sugar can also be converted into fat in the body, and make blood lipids rise. Fructose contained in fruits and honey is not only easy to digest and absorb, but also difficult to be converted into fat in the body, so it is an ideal sugar source for the elderly.
5. minerals
Minerals have very important functions in the body, which are not only important components of bones and teeth, but also can adjust the acid-base balance in the body, maintain the osmotic pressure of tissues and cells, maintain the excitability of neuromuscular, and constitute some important physiologically active substances in the body, such as hemoglobin and thyroxine.
(1) calcium. The absorption rate of calcium for the elderly is generally below 20%. Insufficient calcium intake can easily lead to the negative balance of calcium in the elderly, and the reduction of physical activity can reduce the deposition of calcium in bones, thus leading to osteoporosis and bone neck fracture. Therefore, adequate supply of calcium is very important. China Nutrition Society recommends that the daily dietary calcium supply for adults is 800mg, which can meet the needs of the elderly.
(2) iron. The elderly people's ability to absorb and utilize iron decreases, their hematopoietic function decreases, and their hemoglobin content decreases, which is prone to iron deficiency anemia. Therefore, the intake of iron needs to be sufficient. China Nutrition Society recommended that the dietary iron supply for the elderly should be 12mg per day.
In addition, zinc, copper, chromium and other trace elements need to be supplemented in daily diet to meet the needs of the body.
6. Vitamins
Vitamins are essential nutrients for maintaining health, promoting growth and regulating physiological functions. Although the physiological demand of vitamins is very small, most vitamins cannot be synthesized in the body or stored in tissues in large quantities, and must be supplied through food frequently. Due to the decline of metabolism and immune function, the elderly should take enough vitamins to promote metabolic balance and disease resistance.
(1) Vitamin A. The elderly are prone to vitamin A deficiency due to reduced food intake and decreased physiological function. The recommended amount of vitamin A in the diet is 800 micrograms per day.
(2) Vitamin D. Due to the decrease of outdoor activities, the amount of vitamin D formed by the skin decreases, and the function of liver and kidney decreases, which leads to the decrease of active forms converted into 1, 25 (OH) 2d3 through liver and kidney, which is prone to vitamin D deficiency. Therefore, the daily intake of vitamin D should reach 10μg(400IU).
In addition, the maximum daily intake of vitamin E should not exceed 400mg, and the recommended daily dietary amount of thiamine and riboflavin is1.3 mg; ; The recommended daily dietary amount of ascorbic acid is 100mg.
7. Edible fiber
Dietary fiber can increase intestinal peristalsis and prevent senile constipation; Can improve intestinal flora and make food easy to digest and absorb; Dietary fiber, especially soluble fiber, can improve blood sugar and blood lipid metabolism, and these functions are especially beneficial to the elderly. With the increase of age, the incidence of non-communicable chronic diseases such as cardiovascular and cerebrovascular diseases, diabetes, cancer and so on increases. Has increased significantly, and dietary fiber is also conducive to the prevention of these diseases. Coarse grains and vegetables contain a lot of dietary fiber, and the elderly should pay attention to strengthening the intake of food in this area. Dietary guide for the elderly
The nutritional needs of the elderly have certain characteristics, such as lower basal metabolism, less activity and less total calories than adults. The nutritional needs of each elderly person vary according to their living environment, living habits, work nature and individual differences (weight, disease, gender, etc.). ). But the general requirement is: strive for a comprehensive, balanced, adequate and reasonable nutrition, pay attention to scientific nutrition, and make yourself roughly meet the needs of standard weight.
Among the nutritional elements of the elderly, it is particularly noteworthy that the proportion of protein, especially high-quality protein, in food should be appropriately increased, and it is generally better to reach half of the total amount of protein needed, while excessive protein will damage the kidneys.
The vast majority of people in China are still dominated by plant foods, so we should gradually change the diet structure and appropriately increase legumes and animal foods. The elderly should have reduced their sugar diet, but many people dare not eat animal fat, which leads to a great increase in sugar diet, which will lead to hyperlipidemia, atherosclerosis and diabetes. Foods containing calcium and cellulose should be sufficient, with low sodium content, and a light diet is beneficial. The daily content of sodium salt should be below 5g. Eating coarse grains has become a fashion for the contemporary elderly. The combination of coarse grains and flour and rice can improve the nutritional value. The food that is easy to digest and chew is the prayer of the elderly.
Elderly people with gastrointestinal dysfunction should choose digestible food to facilitate absorption and utilization. But the food should not be too delicate, but should pay attention to the thickness. On the one hand, the staple food should be matched with coarse grain flour and rice, and coarse grains such as oats and corn contain more dietary fiber than rice and wheat; On the other hand, food processing should not be over-refined. Excessive refined grain processing will lose a lot of dietary fiber and vitamins and minerals contained in grain endosperm.
Vitamin E contained in endosperm is an antioxidant vitamin, which plays an important role in human antioxidant function. The decline of antioxidant capacity of the elderly increases the risk of non-communicable chronic diseases, so it is necessary to take enough antioxidant nutrients from the diet. Other trace elements, such as zinc and chromium, play an important role in maintaining normal glucose metabolism.