Effects Of Diet Change Research Articles

黒毛和種牛における給与飼料変更後の胃汁および血液性状の変化と子牛白痢の発症

黒毛和種牛における給与飼料変更後の胃汁および血液性状の変化と子牛白痢の発症

The history of folic acid.

The history of folic acid.

Effect of long-term changes in diet and exercise on plasma leptin concentrations

Although it is known that plasma leptin concentrations correlate with the amount of adipose tissue in the body, little information is available on the long-term effects on leptin concentrations of changes in diet and exercise. We wanted to examine whether changes in dietary energy sources and exercise-mediated energy expenditure, alone or in combination, affect plasma leptin concentrations. In a randomized, 2 x 2 factorial trial, 186 men with metabolic syndrome were divided into 4 groups: diet, exercise, a combination of diet and exercise, and control. Data on dietary intake, physical fitness, and demographics were collected and plasma leptin concentrations were measured before and after a 1-y intervention period. Plasma leptin concentrations, body mass index, and fat mass decreased in association with long-term reductions in food intake as well as increased physical activity. By adjusting for either body mass index or fat mass, we observed a highly significant reduction in plasma leptin concentration after both the diet and the exercise interventions. There was no interaction between the interventions, suggesting a direct and additive effect of changes in diet and physical activity on plasma leptin concentrations. Long-term changes in lifestyle consisting of decreased intake of dietary fat and increased physical activity reduced plasma leptin concentrations in humans beyond the reduction expected as a result of changes in fat mass.

Trends in the Incidence of Coronary Heart Disease and Changes in Diet and Lifestyle in Women

Background Previous studies have found concurrent declines in blood pressure, serum cholesterol levels, and the incidence of and mortality from coronary disease. However, the effects of changes in diet and lifestyle on trends in coronary disease are largely unknown. Methods We followed 85,941 women who were 34 to 59 years old and had no previously diagnosed cardiovascular disease or cancer from 1980 to 1994 in the Nurses' Health Study. Diet and lifestyle variables were assessed at base line and updated during follow-up. Results After adjustment for the effect of age, the incidence of coronary disease declined by 31 percent from the two-year period 1980–1982 to the two-year period 1992–1994. From 1980 to 1992, the proportion of participants currently smoking declined by 41 percent, the proportion of postmenopausal women using hormone therapy increased by 175 percent, and the prevalence of overweight, defined as a body-mass index (the weight in kilograms divided by the square of the height in meters) of 25 ...

Trends in the incidence of coronary heart disease and changes in diet and lifestyle in women.

Previous studies have found concurrent declines in blood pressure, serum cholesterol levels, and the incidence of and mortality from coronary disease. However, the effects of changes in diet and lifestyle on trends in coronary disease are largely unknown. We followed 85,941 women who were 34 to 59 years old and had no previously diagnosed cardiovascular disease or cancer from 1980 to 1994 in the Nurses' Health Study. Diet and lifestyle variables were assessed at base line and updated during follow-up. After adjustment for the effect of age, the incidence of coronary disease declined by 31 percent from the two-year period 1980-1982 to the two-year period 1992-1994. From 1980 to 1992, the proportion of participants currently smoking declined by 41 percent, the proportion of postmenopausal women using hormone therapy increased by 175 percent, and the prevalence of overweight, defined as a body-mass index (the weight in kilograms divided by the square of the height in meters) of 25 or more, increased by 38 percent. During the study period, diet improved substantially. Statistically, changes in these variables--when considered simultaneously--explained a 21 percent decline in the incidence of coronary disease, representing 68 percent of the overall decline from 1980-1982 to 1992-1994. Taken individually, the reduction in smoking explained a 13 percent decline in the incidence of coronary disease; improvement in diet explained a 16 percent decline; and increase in postmenopausal hormone use explained a 9 percent decline. On the other hand, the increase in body-mass index explained an 8 percent increase in the incidence of coronary disease. Reduction in smoking, improvement in diet, and an increase in postmenopausal hormone use accounted for much of the decline in the incidence of coronary disease in this group of women. An increasing prevalence of obesity, however, appears to have slowed the decline in the incidence of coronary disease.

Digestive kinematics of suspension-feeding bivalves:modeling and measuring particle-processing in the gut of Potamocorbula amurensis

Particle digestion in lamellibranch bivalves is partitioned between 2 paths, an 'intestinal' path through the stomach and intestine and a 'glandular' path through the stomach, digestive gland and intestine. In the Asian clam Potamocorbula amurensis (Schrenck, 1867), the relative importance of the intestinal path increases compared to the glandular path as food availability and ingestion rate increases. The effects of changes in food availability and ingestion rate on digestive partitioning are at least as important as the effect of changes in diet observed by other investigators. Analyses of residence-time distributions of inert 9 and 44 pm particle tracers show that the gut of P amurensis can be modeled as an ideal mixing reactor (stomach and digestive gland) and an ideal plug-flow reactor (intestine) in series. This model appears to be valid for the processing of particles ≤ 9 μm in size. For particles of ≥15 μm, the ideal mixing component of the model must be modified to account for channeling of particles through the stomach to the intestine. Larger particles can enter the digestive gland, but are probably not phagocytized for intracellular digestion. Instead they may clog the ducts and tubules, limiting phagocytosis of smaller particles and potentially reducing the extent of digestion and absorption. Mixing, and the resultant intragut particle-sorting thus appear to be necessary components of a digestive strategy that incorporates intracellular digestion.

Sampling techniques for and interpretation of milk urea nitrogen concentration (1998)

Representative MUN values can be obtained by testing a milk sample before milking, at AM or PM milking, or with an in-line siphon sampling device. MUN values obtained from homogenous milking strings are as accurate as an average MUN value obtained by sampling each cow in the string. Bulk tank sampling is not advisable because of the variation in MUN caused by stage of lactation. Small herds that feed a single TMR should use the average MUN from cows between 60 and 200 days in milk. Monthly sampling is recommended to build a database. The effect of diet changes on MUN can be assessed within 7 days.

A low allergen diet is a significant intervention in infantile colic: Results of a community-based study

Background: The effect of diet change in 38 bottle-fed and 77 breast-fed “colicky” infants, referred from community-based pediatric facilities was studied over a 1-week period in a double-blind (within each feeding mode), randomized, placebo-controlled trial. Methods: Bottle-fed infants were assigned to either casein hydrolysate or cow's milk formula. All mothers of breast-fed infants were started on an artificial color-free, preservative-free, additive-free diet and also randomized to an active low allergen diet (milk-, egg-, wheat-, nut-free) or a control diet. Results: The response to diet was assessed on day 1 and day 8 with the use of a previously validated infant distress chart on which parents recorded distress levels. If successful outcome was defined as a reduction in distress of 25% or more, after adjusting for age and feeding mode, infants on active diet had a significantly higher rate of improvement than those on the control diet (odds ratio, 2.32; 95% confidence interval, 1.07-5.0; p = 0.03). Analysis of the day 8 to day 1 distress ratio, again adjusted for age and feeding mode, showed that infants on the active diet had distress reduced by 39% (95% confidence interval, 26-50) compared with 16% (95% confidence interval, 0-30) for those on the control diet ( p = 0.012). Conclusion: The results suggest a period of dietary modification with a low allergen diet and appropriate nutritional support should be considered in healthy infants with colic. (J A LLERGY C LIN I MMUNOL 1995;96:886-92.)

The effect of diet changes on the immune system of breast cancer patients

A pilot study was conducted to evaluate the effect of diet on immune function in breast cancer patients. Nine premenopausal post therapy breast cancer patients were included in this study. On day 0, patients were instructed to go off their own diet and to follow the American Cancer Society (ACS) dietary guidelines for the next 28 days. The ACS dietary guidelines followed were high in fiber and consisted of 20% of total calories from fat. On day 29, patients were instructed to continue following the ACS dietary guidelines but to also include fish which were high in ω-3 fatty acids (fa) [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] in their diet 5 times per week through day 56. Twenty-four hour urine samples, blood samples, and 3 day diet records were obtained on days 0, 28, and 56. Patients were monitored for their lymphocyte subsets, T cell function (T cell proliferation and cytolytic response), and urinary prostaglandin E2 (PGE2). Due to diet changes, percent calories from fat decreased from day 0 to days 28 (p=.002) and 56 (p=.004). Serum ω-3 fa, EPA increased from day 28 to 56 (p=.016), and DHA increased from day 28 to 56 (p=.022). The percentage of CD4 T cells (helper T cells) increased from day 0 to day 28 and day 56 (p=.0476). The percentage of CD8 T cells (cytotoxic/suppressor T cells) decreased from day 0 to days 28 and 56 (p=.0024). The CD4/CD8 ratio also changed by days 28 and 56 (p=.0004). Functional studies showed that proliferation of T helper cells [measured in mixed lymphocyte culture (MLC)] increased from day 0 to days 28 and 56 (p=.0052). Significant changes were not observed in cytolytic activity of T cells [measured by cell mediated lysis (CML)], NK cells, total T and B cells, or in urinary PGE2. The results of the study suggest that breast cancer patients may benefit from following ACS dietary guidelines and consuming fish high in ω-3 fa to enhance their immune system.

Thyroid Hormone Concentrations in Nepal: A Study of Potential Gurkha Army Recruits. The Effect of Changes in Diet

A group of non goitrous, potential Gurkha army recruits were tested in Nepal for serum free triiodothyronine (fT3), free thyroxine (fT4) and thyrotropin (TSH) concentrations. Twenty-five percent of the men were recruited into the army and urine samples taken for analysis of iodine and creatinine. Twenty per cent of the recruits underwent thyrotropin releasing hormone (TRH) stimulation tests. After ten months basic training on a diet considered to be iodine sufficient, the tests were repeated on the same men. The results were also compared to army recruits in the UK. All the potential Gurkha recruits had higher serum levels of thyroid hormones than the UK recruits. Some regional differences were found with those men from the Western recruiting depot having lower fT4 and higher TSH concentrations. Urinary iodine and creatinine concentrations showed evidence of slight relative malnutrition and iodine deficiency which was more pronounced in the Western depot. TRH stimulation tests showed no evidence of thyroid dysfunction but highlighted the differences between the Eastern and Western groups. After ten months on an iodine sufficient diet the serum thyroid hormone concentrations became closer to those of the UK recruits, showing any differences to be reversible. The results from the two Gurkha groups became similar which was reflected in the urine analysis results.

Suppressive effect of glucose administration on the binding of prolactin by rat liver

In an attempt to elucidate the physiologic role of the hepatic receptors for prolactin (PRL), we studied the effect of changes in diet on the specific binding of 125I-ovine prolactin (oPRL) by membranes from female rat liver. Specific binding of PRL (SBP) was decreased by over 50% in rats fed 15% glucose ad lib for 2 days, as compared with fasted rats ( P < .01), while serum PRL was similar in both groups. Feeding 20% glucose by tube decreased SBP significantly, but tube-feeding equicaloric amounts of rat or protein-amino acid solution did not. Glucose feeding did not decrease the specific binding of 125I-bovine growth hormone (bGH) to liver, or decrease SBP to membranes of nitrosomethylurea (NMU)-induced mammary carcinomas, indicating that the effect of glucose on hepatic SBP is selective. Administration of glucose decreased SBP significantly in adrenalectomized-ovariectomized rats, in adrenalectomized-chemically sympathectomized rats, and in hypophysectomized rats receiving replacement therapy, including bovine prolactin (bPRL), bGH, hydrocortisone, estrogen, and thyroid hormones. Thus, the effect of glucose is not mediated by a factor from the adrenals, ovaries, or pituitary, and probably not by catecholamines. Administration of insulin to fasted diabetic rats did not alter SBP. Infusion of glucagon for 1 day, at a rate that did not alter serum glucose, increased hepatic SBP 29% ( P < .01). Since glucose administration decreases plasma glucagon, we hypothesize that glucagon may contribute to the maintenance of the hepatic PRL receptors, and that the suppressive effect of glucose on hepatic SBP may be mediated at least in part by suppression of plasma glucagon. The present observations raise the possibility that in the female rat, the hepatic PRL receptors are involved in the metabolic response of the liver to alterations in carbohydrate intake.

Influence of Diet on the Development of Gastrin‐ and Somatostatin‐Like Immunoreactivity in the Stomach of Rats

The effects of changes in diet on antral gastrin‐like immunoreactivities and antral and corporal somatostatin‐like immunoreactivities were studied in three groups of young male rats. Group 1 rats were weaned physiologically, group 2 rats received only breast milk, and group 3 rats were fed milk until 20 days of age and then were switched abruptly to laboratory chow. In group 1, antral gastrin‐like immunoreactivity and somatostatin‐like immunoreactivity increased gradually from 13 days of age to adults. In group 2, antral gastrin‐like immunoreactivity did not increase, and antral and corporal somatostatin‐like immunoreactivity increased until 20 and 25 days of age, respectively. In group 3, there were three‐ to fivefold increases of antral gastrin‐like immunoreactivity and somatostatin‐like immunoreactivity after changing to laboratory chow. Dietary changes had no effect on the concentration of corporal somatostatin‐like immunoreactivity. These results suggest that the developmental patterns of gastric gastrin‐like immunoreactivity and somatostatin‐like immunoreactivity are closely related to diet; laboratory chow may play an important role in the development of these gut hormones.

Ischemic heart disease: An epidemic on the wane?

The available evidence suggests that the decrease in mortality from ischemic heart disease has been due to the combined effects of changes in diet, cessation of smoking, better control of hypertension and coronary care units. At present it is not possible to quantify the relative contributions of primary and secondary prevention. Reliable and unbiased estimates of the incidence of coronary disease are the data which would contribute most to making this important differentiation. Such information would assist policy-makers in the rational allocation of scarce resources between costly, competing preventive programs.

AN EXPLANATION FOR THE VIVACITY AND TALENT OF IRISH YOUTH, ACCORDING TO SIR JOHN SINCLAIR

Scotsmen, such as the scholarly Sir John Sinclair (1754-1835), have long sought an explanation for the vivacity and talent of Irish youth. As Sinclair mentions below, Irish peasant youths "displayed a degree of shrewdness exceeding what is generally met with from youth of a more exalted walk of life in England." Sinclair, a barrister (Lincoln's Inn), President of the Board of Agriculture of Scotland, and an avid observer of children's growth and development, thought that the vegetable diet of the poor children in Ireland played an important part in making Irish youth (and adults, too) so lively and intelligent. He wrote: There cannot be a doubt that the diet of the Irish is highly favorable to vivacity and talent. It is stated in the Code of Health that vegetable food has a happy influence on the mind, and tends to preserve a delicacy of feeling, a liveliness of imagination, and an acuteness of judgment, seldom enjoyed by those who live principally upon animal food. The latter is better calculated for those who labor with the body; but the celebrated Franklin ascertained that a vegetable diet promoted clearness of ideas and quickness of thought, and that a transition from vegetable to animal food produces injurious effects. A friend states that he has more than once selected from his tenant's children a boy remarkable for that smartness of intelligence so common in the Irish youth, while in the capacity of errand boys on the farm, or helpers in the stables, and before they became pampered with better food than their parent's cabin afforded. The lads were at first lively and intelligent, and displayed a degree of shrewdness exceeding what is generally met with from youth of a more exalted walk of life in England. But he invariably found that in proportion as these boys were better fed, they relaxed in activity, became dull and stupid; and he is confident that the change in disposition sprang from the effect of change in diet, and was not owing to corruption of mind from their intercourse with the other servants. In fact they lose all that vivacity of manner so inherent in the Irish boys, whether born in the vast bog of Allan, or in the dry and rocky counties of Mayo and Galway. He is therefore inclined to think that the character of the people does not depend so much upon climate or soil, as upon food, for no part of the globe can differ more than these parts of that kingdom.1

The Effect of Changes in Diet on the Volume and Composition of Rat Milk: Four Figures

Milk from individual stock rats has been analyzed for protein, fat, ash, calcium, phosphorus and magnesium. The effect of changes in the diet of lactating rats has been studied by observing the change in composition of the milk, the number and size of young raised, and the effect of the diet on the mother rat. It is concluded that: Increase in the protein intake results in increased milk yield, but no significant change in the per cent protein in the milk. High calcium diets result in decrease in both milk volume and the percentage of calcium and phosphorus in the milk, with consequent decrease in the total amount of calcium and phosphorus secreted. High phosphorus diets had no demonstrable effect on these milk constituents. Decrease in the intake of yeast decreases the volume of milk, the size of nursing young, and causes severe weight loss in the lactating mothers, without changing significantly the composition of the milk.

Effect of Diet on Insulin Response in Normal and Hypophy-sectomized Dogs

In another paper1 are described the effects of high fat-low carbohydrate and low fat-high carbohydrate diets on the glucose tolerance in normal and hypophysectomized dogs. We report here the effect of similar diets on the insulin response of such animals.Ten normal dogs were fed from one to 3 weeks on a diet consisting of 100 gm. of fat and 350 gm. raw lean meat daily. The animals were then given 0.5 units of insulin per kilo of body weight intravenously and their response to insulin determined by blood sugar determinations made at the intervals indicated in the table. The same animals were then given a low fat-high carbohydrate diet consisting of 100 gm. cane sugar, one liter of skimmed milk and 300 gm. of whole wheat bread daily for a similar time period. Their insulin response was again determined.The results are presented in Table I. Their analysis shows no consistent effect of change in diet on insulin response.Six hypophysectomized dogs within 2 months following the operation were given the above di...

Diet and Colour of Birds

DURING the past year (1935), work was begun to improve the feeding routine of all animal groups at the Zoological Garden in Philadelphia. Efforts are being made to devise food mixtures that are complete in all known essentials, contain a wide variety of materials and allow for seasonal abundance so as to be economical, and are similar in general physical characters to natural foods. From time to time, various factors have necessitated modifications of formulae, so that complete descriptions of the diets to which reference will be made are better postponed. Eventually records of these studies will be used as the subject matter of a report on methods of feeding wild animals in captivity. In spite of the present incompleteness of the investigation, however, certain effects of changes in diet upon the colours of the plumage of several species of birds seem worthy of record at this time.

The Effects of Changes in Diet on the Incidence, Distribution and Numbers of Certain Intestinal Protozoa of Frog and Toad Tadpoles

So far as known to the writer no studies have been published on the relations between the diet of an animal and the incidence, distribution and numbers of the intestinal protozoa with which it may be infected. In the following pages are recorded the results of some investigations in this field. The host animals used were principally tadpoles of the green frog, Rana clamitans, and of the leopard frog, R. pipiens, and toad, Bufo lentiginosus americanus. The protozoa studied were two ciliates of the genera Opalina and Nyctotherus, and two flagellates of the genera Trichomonas and Hexamitus. Other protozoa are more or less regular inhabitants of the digestive tract of these tadpoles but the four mentioned are usually numerous and easily found and are often present in 100 per cent. of the tadpoles examined. Tadpoles of the green frog were selected for special study for several reasons: (1) they do not metamorphose the first season and hence can be obtained, at least in the southern part of their range, at any time of the year; (2) they are hardy and can be subjected to severe experimental conditions without great mortality; (3) they are usually well infected with intestinal protozoa, and (4) one type of protozoon, an Opalina, is an inhabitant of the tadpole but not of the adult (Metcalf, in litt.),t a condition that affords an interesting problem for investigation. In certain other species of frogs and toads the infection with Opalina appears to be continuous from tadpole to adult. The observations and experiments described below involve a study of (1) changes that occur in the protozoan fauna of the green frog during the tadpole stage and the process of metamorphosis; (2) factors