Increased intake of fruits and vegetables in overweight subjects: effects on body weight, body composition, metabolic risk factors and dietary intake.

A diet rich in fruits and vegetables has been associated with several health benefits. However, the effects on body weight (BW) and metabolic markers are not fully known. The present study investigated the effects of increased intake of fruits and vegetables in overweight and obese men and women on dietary habits, anthropometry and metabolic control. In a 16-week controlled intervention, thirty-four men and thirty-four women aged 35-65 years (BMI>27 kg/m2) were randomised to an intervention (IN) or a reference (RG) group. All participants received general dietary advice, and subjects in the IN group received fruits and vegetables for free, of which ≥500 g had to be eaten daily. BW, waist circumference (WC), sagittal abdominal diameter (SAD), plasma insulin, blood glucose, glycated Hb (HbA1c), serum lipids, blood pressure, plasminogen activator inhibitor-1 activity, urinary isoprostane (iso-8-PGF 2α) and serum carotenoids were measured. Diet was assessed using 3-d weighed food records. In all, thirty subjects in the IN group and thirty-two in the RG group completed the intervention. Intake of fruits and vegetables doubled in the IN group, whereas intake of fruits increased in the RG group. Serum α- and ß-carotene concentrations and intakes of folate and vitamin C increased significantly in the IN group. Energy intake, BW, WC and SAD decreased significantly in both groups. Supine systolic blood pressure decreased significantly in the IN group, with no between-group differences. No significant changes were observed for other metabolic markers. Provision of fruits and vegetables led to substantially increased intakes, with subsequent favourable changes in anthropometry and insulin levels, which tended to be more pronounced in the IN group. The observed improvements may, in combination with improved nutritional markers, have health benefits in the long term.

A gene variation (rs12691) in the CCAT/enhancer binding protein α modulates glucose metabolism in metabolic syndrome.

BACKGROUND AND AIMS: CCAAT/enhancer-binding protein alpha (CEBPA) is a transcription factor involved in adipogenesis and energy homeostasis. Caloric restriction reduces CEBPA protein expression in patients with metabolic syndrome (MetS). A previous report linked rs12691 SNP in CEBPA to altered concentration of fasting triglycerides. Our objective was to assess the effects of rs12691 in glucose metabolism in Metabolic Syndrome (MetS) patients. METHODS AND RESULTS: Glucose metabolism was assessed by static (glucose, insulin, adiponectin, leptin and resistin plasma concentrations) and dynamic (disposition index, insulin sensitivity index, HOMA-IR and acute insulin response to glucose) indices, performed at baseline and after 12 weeks of 4 dietary interventions (high saturated fatty acid (SFA), high monounsaturated fatty acid (MUFA), low-fat and low-fat-high-n3 polyunsaturated fatty acid (PUFA)) in 486 subjects with MetS. Carriers of the minor A allele of rs12691 had altered disposition index (p = 0.0003), lower acute insulin response (p = 0.005) and a lower insulin sensitivity index (p = 0.025) indicating a lower insulin sensitivity and a lower insulin secretion, at baseline and at the end of the diets. Furthermore, A allele carriers displayed lower HDL concentration. CONCLUSION: The presence of the A allele of rs12691 influences glucose metabolism of MetS patients.

Glucose and insulin responses in healthy women after intake of composite meals containing cod-, milk-, and soy protein.

OBJECTIVE: To evaluate the metabolic effect of three different kinds of dietary proteins as part of composite meals with similar macronutrient composition in healthy subjects. DESIGN: A randomised meal study. SETTING: Metabolic ward. SUBJECTS AND METHODS: In total, 17 healthy women, 30-65 years old, consumed three meals in randomised order. The meals consisted of foodstuffs with similar nutrient composition but different types of protein (cod, cottage cheese, or soy protein isolate). The distribution of energy from protein, fat and carbohydrates was 33, 26, and 41 energy percent, respectively. Total amount of energy was 2300 kJ. Blood samples were drawn for assay of B-glucose, S-insulin, S-free fatty acids, S-triglycerides, and C-peptide in the fasting state and at seven times (20, 40, 60, 90, 120, 180, and 240 min) after starting to eat the test meal. RESULTS: The blood glucose response after the cod protein meal differed from that of the soy protein meal, with a larger area under the curve (AUC) calculated up to 120 min. The serum insulin response after the milk protein meal differed from that of the cod protein meal with a larger AUC calculated up to 240 min. The insulin/C-peptide and the insulin/glucose ratios differed between the meals; the insulin/C-peptide ratio was higher after the milk protein meal compared to the cod, and soy protein meal at 120 min. The insulin/glucose ratio was lower after the cod protein meal compared to the milk, and soy protein meals at 120 min. The results showed that the metabolic responses differed after meals with similar macronutrient composition containing cod-, milk-, or soy protein.

Conservative treatment of obesity in an academic obesity unit. Long-term outcome and drop-out.

OBJECTIVE: The aim of this study was to explore the outcome and the problems of drop-out in the treatment of obese outpatients at an academic obesity unit. DESIGN: A two-year clinical treatment evaluation. SUBJECTS: A total of 117 obese subjects, 83 women and 34 men, mean aged 50 (23-70) years, with an average body mass index (BMI) of 39.0 kg/m2 (28.8- 64.7). INTERVENTION: All treatment was based on group therapy and included behaviour modification and nutrition counselling. A team of nurses, dieticians, a physiotherapist, a psychotherapist and a physician supervised the treatment. Two programmes were used. Group 1 initially received a low-calorie diet (LCD) for seven weeks combined with the behaviour treatment programme. Group 2 was treated with the behaviour treatment programme only. All subjects were offered complementary treatment according to their medical needs. RESULTS: There was a continuous drop-out of subjects during the two-year treatment period with an overall drop-out rate of 53%. Anthropometric characteristics, medical history or reasons for drop-out had no impact on the drop-out rate. In completers the weight reduction after two years was 9.2 [+/-10.8 standard deviation (S.D.) kg. In non-completers the weight reduction of the last observed weight measurement was 4.7 (+/-7.9 S.D.) kg. After year two, the weight reduction in Group 1 was 8.8 (+/-12.2 S.D.) kg, and in Group 2 was 9.7 (+/-8.0 S.D.) kg. CONCLUSION: This study has showed the difficulties of long-term clinical treatment of obese outpatients, even in a specialised obesity clinic. The findings demonstrate that educated and experienced staff together with an extended package of treatment options is not enough to keep patients in treatment for two years. However though the drop-out rate was high, two thirds of the included subjects reduced their weight, which is a satisfactory result in a clinical setting. The drop-out rate and the reasons for dropping out could give a clue in which direction the diagnostics and analysis of the subject's individual needs in health care should be directed.

Improved glycemic control and lipid profile and normalized fibrinolytic activity on a low-glycemic index diet in type 2 diabetic patients.

OBJECTIVE: To evaluate the effects of varying the glycemic index (GI) of carbohydrate-rich foods on metabolic control in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: In a randomized crossover study, 20 patients, 5 women and 15 men, were given preweighed diets with different GIs during two consecutive 24-day periods. Both diets were composed in accordance with dietary recommendations for people with diabetes. The macronutrient composition and type and amount of dietary fiber were identical. Differences in GI were achieved mainly by altering the structure of the starchy foods. RESULTS: Peripheral insulin sensitivity increased significantly and fasting plasma glucose decreased during both treatment periods. There was a significant difference in the changes of serum fructosamine concentrations between the diets (P < 0.05). The incremental area under the curve for both blood glucose and plasma insulin was approximately 30% lower after the low- than after the high-GI diet. LDL cholesterol was significantly lowered on both diets, with a significantly more pronounced reduction on the low-GI diet. Plasminogen activator inhibitor-1 activity was normalized on the low-GI diet, (-54%, P < 0.001), but remained unchanged on the high-GI diet. CONCLUSIONS: A diet characterized by low-GI starchy foods lowers the glucose and insulin responses throughout the day and improves the lipid profile and capacity for fibrinolysis, suggesting a therapeutic potential in diabetes.

The influence of food structure on postprandial metabolism in patients with non-insulin-dependent diabetes mellitus.

Two natural-food mixed meals composed in accordance with the present dietary recommendations were given to 10 diabetic patients on two occasions. The meals were planned to achieve large differences in glycemic index (GI) by altering the food structure but maintaining an identical nutrient composition. In the first study, two meals were compared that contained either pasta or bread made from durum wheat flour. In the second experiment a meal with parboiled rice, red kidney beans, and bread made from whole-wheat grains was compared with a meal of sticky rice, ground red kidney beans, and bread made from ground wheat. All of the other ingredients in these meals were identical. The area under the curve for blood glucose (BG) and plasma insulin (PI) was significantly lower after the meal with pasta (BG: -35%, P < 0.05; PI: -39%, P < 0.05) and the meal with parboiled rice (BG: -42%, P < 0.001; PI: -39%, P < 0.01), respectively, compared with the corresponding high-GI meals. The results shows the importance of preserved structure in common foods and support the applicability of the GI concept to mixed meals.

Reduction of high density lipoprotein cholesterol and apoliproprotein A-I concentrations by a lipid-lowering diet.

Nine hyperlipoproteinaemic patients were treated with a serum lipid-lowering diet during 4 weeks in a metabolic ward. The diet contained 35% energy from fat and the ratio between polyunsaturated and saturated fats (the P/S ratio) was 2.0. This treatment caused a reduction of the serum concentrations of the low density lipoprotein cholesterol (Chol) by 17% (P less than 0.01), of the apolipoprotein (apo) B by 27% (P less than 0.01), of high density lipoprotein (HDL) Chol by 15% (P less than 0.05) and of the apo A-I by 9% (P less than 0.02). The apo B/apo A-I ratio decreased by 19% (P less than 0.01). It is suggested that the reduced HLD Chol and apo A-I concentrations may be due to both the qualitative change to more polyunsaturated fats in the diet and to the reduction of the total dietary fat intake.

Dietary habits and effects of dietary advice in patients with type 2 diabetes. Results from a one-year intervention study.

The diets of 22 patients with type 2 diabetes were evaluated by a dietary-history interview. Sixteen of the patients were also interviewed after a 1-year intervention period, to find out whether continuous contact with a dietitian at a health centre could influence the food habits and thereby improve the metabolic control. In most participants the diabetes was fairly well controlled on entry into the study. Another 24 patients took part in the same intervention programme but did not agree to participate in the dietary-history interview. These subjects had, in general, a poorer metabolic control on admission. According to the study design, the patients were to make four visits to the dietitian during the first 6 months, and one visit at the end of the year. The patients were advised to eat a fat-modified, fibre-enriched diet. Among the patients who completed both the intervention programme and the dietary-history interviews there were significant reductions in mean body weight, haemoglobin A1c and serum triglycerides during the first half of the study. After 12 months, however, only the mean body weight and serum triglycerides remained lower than before the intervention period. A study of the fatty acid composition of the plasma cholesterol esters showed a significant reduction of the content of oleic acid (18:1 n-9). The dietary interviews indicated only minor changes (not significant) in the intake of energy and different nutrients, including dietary fibre, after 1 year. However, the effects of the intervention were better in the patients who did not participate in the dietary interview with significant reductions in the mean body weight, fasting blood glucose, haemoglobin A1c and serum triglycerides also after 1 year.

Effects of four meals with different kinds of dietary fibre on glucose metabolism in healthy subjects and non-insulin-dependent diabetic patients.

The effects of four mixed meals on glucose metabolism were studied during a 4-h period in 12 healthy women and in 13 women with non-insulin-dependent diabetes. Three test meals containing different types of dietary fibre in realistic amounts (cereal, leguminous and mixed-fibre), and one control meal were prepared. Each meal was calculated to contain 2.1 MJ (500 kcal) and the energy distributions of protein, fat and carbohydrate (by difference) were 15, 29-31 and 56-58 per cent, respectively. Results of analyses of the mixed meals, performed after the clinical study, showed unexpectedly large deviations from the calculated values regarding digestible carbohydrates in the leguminous meal. In the healthy group the blood glucose concentrations after the four meals did not differ significantly. In the diabetic group the area under the curve of blood glucose values was significantly smaller after both the leguminous meal and that containing mixed dietary fibre than after the control meal (P less than 0.001). There were also significant differences in blood glucose between the cereal meal and the leguminous and mixed-fibre meals (P less than 0.001), and between the leguminous meal and the mixed-fibre meal (P less than 0.05). In the healthy group the insulin response was significantly lower after the leguminous meal than after the control meal (P less than 0.05) whilst the diabetic group showed lower insulin responses after all the high-fibre test meals. Serum triglycerides, cholesterol and HDL cholesterol were similar after the different meals. The lower content of digestible carbohydrates, especially in the leguminous meal, complicates the interpretation of the results.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in food habits in healthy Swedish adolescents during the transition from adolescence to adulthood.

OBJECTIVE: To investigate the change in food habits in Swedish adolescents between 15 and 21 y of age with reference to age, sex, region and socioeconomic background. DESIGN: A longitudinal study from 1993 to 1999. SETTING: Two different regions in Sweden, the university city of Uppsala and the industrial town of Trollhättan. SUBJECTS: On three different occasions, 1993, 1995 and 1999, 208 adolescents, 96 males and 112 females, were studied. METHODS: A food frequency questionnaire containing 29 different food groups was used. The questionnaire also contained questions about food habits and amounts of some food items and socioeconomic conditions of the participants and their families. RESULTS: At 17 and 21 y of age, the adolescents consumed significantly more often pasta, vegetables, coffee and tea compared to age 15, while the frequency consumption of fat spread, milk, bread, potatoes, carrots and buns and biscuits decreased. The changes between 15 and 17 were smaller than between age 17 and 21. At age 21, the males decreased their intake of fruit, while the females decreased their intake of meat. No-meat consumers among females increased from 2 to 13%. Higher educational level of the mothers of the adolescents was associated with more frequent consumption of vegetables and pasta between ages 17 and 21. Milk consumption decreased significantly in both sexes. Breakfast habits did not change: 90% had breakfast five times/week or more. CONCLUSIONS: Food habits change significantly during adolescence along with lifestyle changes. Therefore, health promotion during adolescence ought to be more supported by the society.

Blood flow is an important determinant of forearm glucose uptake following a mixed meal.

Insulin-mediated vasodilation has been suggested to be of importance for glucose uptake during normoglycemic hyperinsulinemia. If this also is valid after an ordinary mixed meal remains to be evaluated. Forearm blood flow (FBF) and forearm glucose uptake change (evaluated by venous occlusion plethysmography) and glucose arteriovenous differences were evaluated over 120 minutes in 10 healthy volunteers following an ordinary mixed meal (700-900 kcal, 34% of energy from fat). Fasting arterial glucose level was 4.9+/-0.9 mmol/l, and the maximum glucose level was reached 30 minutes after the start of ingestion (6.6+/-0.8 mmol/l, p<0.0001). Plasma insulin levels were increased four-fold. FBF increased rapidly within 20 minutes after the start of ingestion and reached its maximum after 50 minutes (94% higher than baseline level, p<0.01). After 2 hours FBF was still substantially elevated (75% above baseline level, p<0.01). Forearm glucose uptake increased fivefold already after 20 minutes ( p<0.01). During the 2 hours, the increase in FBF contributed to 41% of the forearm glucose uptake ( p<0.05). The present study showed that the increase in FBF seen after an ordinary mixed meal is important for the change in forearm glucose uptake. These results support the view that modulation of limb blood flow is a determinant of glucose uptake.

Diet, nutrition and diabetes mellitus.

Nutritional management of diabetes mellitus, and the importance of diet in the development of insulin resistance, have for many years been important areas of research and education at the Unit for Clinical Nutrition Research at the Department of Public Health and Caring Sciences (formerly Department of Geriatrics) at Uppsala University. The research has more recently focussed on effects of dietary fat quality in the development of insulin resistance and in treatment of diabetes, on interaction between dietary fat and physical activity in relation to insulin sensitivity and on the importance of carbohydrate rich foods with low glycaemic index in the diabetic diet. Much work has also been directed towards development of educational material about nutrition recommendations and dietary treatment in diabetes mellitus. The ultimate goals for all our efforts are to visualize, and promote, the possibilities and fundamental importance of lifestyle changes. This includes an improved diet and increased physical activity, in the prevention and treatment of diabetes mellitus.

Changes in lipoprotein metabolism during a supplemented fast and an ensuing vegetarian diet period.

The effect on lipoprotein metabolism of a 2-week modified fast and an immediately ensuing 3-week period on a vegetarian diet was studied under metabolic ward conditions in 21 non-obese female and 6 male patients. The very low calorie diet induced reductions of the cholesterol concentration in all serum lipoprotein classes. In the female patients, who were all normolipoproteinaemic, the triglycerides in serum showed a slight increase during the fast, reflecting small changes in very low (VLDL) and low density lipoprotein triglycerides. This may probably be explained partly by simultaneous significant reductions of both the adipose tissue and skeletal muscle tissue lipoprotein lipase activities (LPLA). In contrast, in the male patients who had a higher VLDL level at admission, the VLDL triglycerides decreased without significant changes of high density lipoprotein (HDL) cholesterol and of LPLA in muscle. The female patients, whose weights were stable during the vegetarian diet, ended up with a lower HDL cholesterol than at the start of the trial. This effect was probably partly due to the high content of polyunsaturated fatty acids in the vegetarian diet. It is concluded that the changes of lipoprotein metabolism during supplemented fasting are quantitatively and qualitatively different in several respects in females and males.

[Diet treatment in clinical practice. Advice on diet--more than a knowledge of dietetics]. / Kostbehandling i praktiken. Råd om mat--mer än kunskap i näringslära.

Eating habits are deeply rooted and founded early in life. The need to change one's eating habits in order to treat a certain disease or a metabolic disorder may seem to impose a well nigh impossible task. It is therefore extremely important that the dietitian adjust the recommendations to each individual's needs, wishes and circumstances. The article translates nutritional objectives into practical advice. The desired dietary composition is essentially the same for the foods which are recommended for the treatment of diabetes, hyperlipoproteinemia and hypertension.

The influence of a high dietary intake of purine-rich animal protein on urinary urate excretion and supersaturation in renal stone disease.

1. Eight recurrent renal stone-forming patients were housed in a metabolic ward and fed on a low (LPD) and a high (HPD) animal protein diet, which were isoenergetic. Metabolic studies were made after 2 weeks on each diet. 2. There was a 90% increase in urinary urate on HPD compared with LPD, whereas serum urate did not change consistently. 3. The urinary acid excretion increased by 200%, including a 100% increase in ammonium ion excretion. A fall in urine pH by 0.9 unit was also seen. 4. The calculated ion activities of the urines revealed a profound increase in the uric acid supersaturation, from undersaturation to supersaturation, and in some cases even surpassing the formation product ratio. The ammonium urate supersaturation also increased. The sodium urate supersaturation was unchanged, despite an induced natriuresis. 5. The risk of forming uric acid or ammonium urate crystals or stones in the urine was increased on a high protein diet, whereas the risk of forming sodium urate crystals was no greater than on a low protein diet. 6. As uric acid and ammonium urate crystals under certain conditions may adsorb a macromolecular fraction of the human urine, which inhibits calcium oxalate crystal growth, it is proposed that this mechanism, along with a decrease in urine pH, may also interfere with the inhibitory activity of calcium oxalate crystal growth and aggregation.

Dietary animal protein and urinary supersaturation in renal stone disease.

Eight stone-forming patients were given diets that were high (HPD) and low (LPD) in dietary animal protein, each for two weeks. Urines were collected by the end of each diet period. Urinary calcium, phosphate, urate and acids were increased on HPD whereas citrate and urine-pH decreased. The urinary supersaturation and thereby the risk of forming crystals and stones of uric acid and ammonium urate was increased on HPD. The supersaturation of calcium oxalate was unchanged, but the inhibition of calcium oxalate crystallisation may have become unfavourably affected.

Diet therapy for poorly controlled type 2 (non-insulin-dependent) diabetes mellitus.

Poorly controlled type 2 diabetes represents a major therapeutic problem. A classification of the disease, based on body weight and presence or absence of adequate insulin-secretion capacity, may be helpful in the choice of correct treatment. Calorie reduction is the most important therapeutic intervention in overweight patients. In the diabetic diet digestible carbohydrates should comprise at least 50 energy%, while the fat content should be reduced below 30 energy%. Controlled clinical studies show that the blood glucose control can be improved and the urinary glucose excretion be diminished by addition of dietary fibre. In obese type 2 diabetics supplemented fasting may be useful to achieve a rapid weight loss and an improved metabolic control. Although our knowledge with regard to the patho-physiology of type 2 diabetes and the effects of dietary treatment has increased during recent years, several important questions remain unanswered. Also there is a great need for education and training programmes to achieve improved compliance to the dietary advice given.

Effects of leguminous seeds in a mixed diet in non-insulin-dependent diabetic patients.

The effects of moderate addition of leguminous seeds to a mixed diabetic diet were evaluated in 15 inadequately controlled patients with non-insulin-dependent diabetes mellitus. A control diet and a diet with an increased content of peas and beans (leguminous diet) were given consecutively for a 3-week period each on a metabolic ward. Seven of the patients started with the control diet and 8 with the leguminous diet. On an energy basis the diets comprised 20% protein and 33-34% fat, the ratio between polyunsaturated and saturated fatty acids was 1.4. The analysed dietary fibre contents of the control and leguminous diets were 24 and 37 g/day per 6.7 MJ (1,600 kcal) respectively. The content of digestible carbohydrates was similar in the 2 diets. The mean body weight did not differ after the 2 dietary treatment periods. All patients showed improved glucose control during treatment irrespective of the type of diet given. The fasting blood glucose concentration on admission was 14.3 +/- 0.9 mmol/l (mean +/- SEM). This value had decreased to 9.9 +/- 0.8 during the last week of the control period and to 9.7 +/- 0.6 during the last week of the leguminous diet period. The mean postprandial glucose concentration at 3 pm was significantly lower during the leguminous diet period. The mean urine glucose excretion was significantly lower during the leguminous diet period. The fasting serum lipid concentrations decreased during treatment with each diet, but there were no significant differences between these values at the end of the 2 diet treatment periods.(ABSTRACT TRUNCATED AT 250 WORDS)