Objectives/Aims:

Fruit is often advocated as a healthy source of nutrients and vitamins. However, the high contents of sugars in many fruits could potentially counteract positive effects on the teeth.

Materials and methods:

We recruited 30 healthy non-obese participants who were randomised to either supplement their diet with extra fruits or nuts, each at +7 kcal/kg body weight/day, for 2 months.

Results:

Fructose intake increased from 9.1±6.0 to 25.6±9.6 g/day, P<0.0001, in the fruit group and was reduced from 12.4±5.7 to 6.5±5.3 g/day, P=0.007, in the nut group. Serum-vitamin C increased in both groups (fruit: P=0.017; nuts: P=0.009). α-Tocopherol/cholesterol ratio increased in the fruit group (P=0.0033) while β-carotene/cholesterol decreased in the nut group (P<0.0001). The amount of subjects with probing pocket depths ⩾4 mm in the fruit group was reduced (P=0.045) according to blinded examinations, and the difference in the changes in probing pockets ⩾4 mm was also statistically significant between the food groups (P=0.010).

Conclusion:

A large increase of fruit intake, compared with nuts, had a favourable effect on periodontal status in some respects, despite the high sugar contents. To search for potential protective micronutrients in fruit that protect the teeth could be an aim for further research.

Background: Low levels of vitamin D have been related to increased mortality and morbidity in several non-diabetic studies. We aimed to prospectively study relationships between serum 25-OH vitamin D-3 (vitamin D) and of serum parathyroid hormone (PTH) to total mortality in type 2 diabetes. We also aimed to compare the levels of these potential risk-factors in patients with and without diabetes. Methods: The main study design was prospective and observational. We used baseline data from 472 men and 245 women who participated in the "Cardiovascular Risk factors in Patients with Diabetes-a Prospective study in Primary care" study. Patients were 55-66 years old at recruitment, and an age-matched non-diabetic sample of 129 individuals constituted controls for the baseline data. Carotid-femoral pulse-wave velocity (PWV) was measured with applanation-tonometry and carotid intima-media thickness (IMT) with ultrasound. Patients with diabetes were followed for all-cause mortality using the national Swedish Cause of Death Registry. Results: Levels of vitamin D were lower in patients with diabetes than in controls, also after correction for age and obesity, while PTH levels did not differ. Nine women and 24 men died during 6 years of median follow up of the final cohort (n = 698). Vitamin D levels were negatively related to all-cause mortality in men independently of age, PTH, HbA1c, waist circumference, 24-h systolic ambulatory-blood pressure (ABP) and serum-apoB (p = 0.049). This finding was also statistically significant when PWV and IMT were added to the analyses (p = 0.028) and was not affected statistically when medications were also included in the regression-analysis (p = 0.01). In the women with type 2 diabetes, levels of PTH were positively related with all-cause mortality in the corresponding calculations (p = 0.016 without PWV and IMT, p = 0.006 with PWV and IMT, p = 0.045 when also adding medications to the analysis), while levels of vitamin D was without statistical significance (p greater than 0.9). Conclusions: Serum vitamin D in men and serum PTH in women give prognostic information in terms of total-mortality that are independent of regular risk factors in addition to levels of ABP, IMT and PWV.

Background

Type 2 diabetes is a common disease and the prevalence has increased in large parts of the world. In treatment of diabetes the type of diet is of great importance considering metabolic factors such as glucose level and blood lipids. Which diet that is most beneficial to avoid diabetic complications has been heavily debated in recent decades. This thesis is based on two clinical studies designed to compare the effects of different macronutrients.

Methods

A clinical trial was designed to compare a low-carbohydrate diet (LCD) to a low-fat diet (LFD) in treatment of patients with type 2 diabetes. Sixty-one patients at two health care centres were included and randomized to get advice to eat a LCD or a LFD. The LCD had an energy content where 50 energy percent (E%) where from fat, 20 E% from carbohydrates and 30 E% from protein. For the LFD the nutrient composition was similar to what is traditionally recommended for treatment of type 2 diabetes in Sweden. Metabolic factors, anthropometrics and questionnaires were analysed.

To study postprandial effects a trial was designed to compare three different diets. Twentyone patients with type 2 diabetes were included to in randomized order test the three types of diets on separate test days. On each test day the patients were served breakfast and lunch and blood samples were taken at six times these days. Glucose, lipids and hormones were analysed.

Results

There were equal weight reduction in the two groups in the first trial during the two-year study period. At six month when compliance was good according to diet-records, the glucose level (HbA1c) was lowered and the HDL-cholesterol was increased in the LCD group. The inflammatory markers IL-6 and IL-1Ra were significantly lower in the LCD group than in the LFD group. At 12 months the physical function, bodily pain and general health  scores improved within the LCD group only.

In the second trial the postprandial glucose and insulin levels were lower on the LCD compared to the LFD. However, the LCD resulted in a tendency to higher postprandial triglyceride levels. The Mediterranean type of diet with all energy intake at lunch resulted in a more pronounced insulin response and a glucose level at lunch similar to that of the low-fat diet. The increase-ratio of insulin correlated to the elevation of the incretin glucose-dependent insulinotropic peptide (GIP).

Conclusions

In the two-year study we found benefits for the LCD group regarding glucose control and insulin doses. Furthermore, only the LCD was found to improve the subclinical inflammatory state and there were some aspects of improved well-being in this group. Aiming for 20% of energy intake from carbohydrates is safe with respect to cardiovascular risk factors  compared with the traditional LFD and this approach could constitute a treatment alternative.

In the postprandial state, the LCD induced lower insulin and glucose excursions than the LFD but at the same time a tendency of higher triglycerides. The long-term significance needs to be further examined. The accumulation of caloric intake from breakfast to lunch to a single large Mediterranean-style lunch-meal in type 2 diabetes might be advantageous from a metabolic perspective.

BACKGROUND: Inflammation may play an important role in type 2 diabetes. It has been proposed that dietary strategies can modulate inflammatory activity.

METHODS: We investigated the effects of diet on inflammation in type 2 diabetes by comparing a traditional low-fat diet (LFD) with a low-carbohydrate diet (LCD). Patients with type 2 diabetes were randomized to follow either LFD aiming for 55-60 energy per cent (E%) from carbohydrates (n = 30) or LCD aiming for 20 E% from carbohydrates (n = 29). Plasma was collected at baseline and after 6 months. C-reactive protein (CRP), interleukin-1 receptor antagonist (IL-1Ra), IL-6, tumour necrosis factor receptor (TNFR) 1 and TNFR2 were determined.

RESULTS: Both LFD and LCD led to similar reductions in body weight, while beneficial effects on glycaemic control were observed in the LCD group only. After 6 months, the levels of IL-1Ra and IL-6 were significantly lower in the LCD group than in the LFD group, 978 (664-1385) versus 1216 (974-1822) pg/mL and 2.15 (1.65-4.27) versus 3.39 (2.25-4.79) pg/mL, both P < 0.05.

CONCLUSIONS: To conclude, advice to follow LCD or LFD had similar effects on weight reduction while effects on inflammation differed. Only LCD was found significantly to improve the subclinical inflammatory state in type 2 diabetes.

Aims

To compare the effects on health-related quality of life (HRQoL) of a 2-year intervention with a low-fat diet (LFD) or a low-carbohydrate diet (LCD) based on four group-meetings to achieve compliance. To describe different aspects of taking part in the intervention following the LFD or LCD.

Methods

Prospective, randomized trial of 61 adults with Type 2 diabetes mellitus. The SF-36 questionnaire was used at baseline, 6, 12 and 24 months. Patients on LFD aimed for 55–60 energy percent (E%) and those on LCD for 20 E% from carbohydrates. The patients were interviewed about their experiences of the intervention.

Results

Mean body-mass-index was 32.7 ± 5.4 kg/m² at baseline. Weight-loss did not differ between groups and was maximal at 6 months, LFD: −3.99 ± 4.1 kg, LCD: −4.31 ± 3.6 kg (p < 0.001 within groups). There was an increase in the physical component score of SF-36 from 44.1 (10.0) to 46.7 (10.5) at 12 months in the LCD group (p < 0.009) while no change occurred in the LFD group (p < 0.03 between groups). At 12 months the physical function, bodily pain and general health scores improved within the LCD group (p values 0.042–0.009) while there was no change within the LFD group.

Conclusions

Weight-changes did not differ between the diet groups while improvements in HRQoL only occurred after one year during treatment with LCD. No changes of HRQoL occurred in the LFD group in spite of a similar reduction in body weight.

Background: In the clinic setting both fasting levels of glucose and the area under the curve (AUC) of glucose, by determination of HbA1c levels, are used for risk assessments, in type 2 diabetes (NIDDM). However little is known about postprandial levels, and hence AUC, regarding other traditional risk factors such as insulin and blood-lipids and how this is affected by different diets. less thanbrgreater than less thanbrgreater thanObjective: To study postprandial effects of three diets, during a single day, in NIDDM. less thanbrgreater than less thanbrgreater thanMethods: A low-fat diet (45-56 energy-% from carbohydrates), and a low-carbohydrate diet (16-24 energy-% from carbohydrates) was compared with a Mediterranean-style diet (black coffee for breakfast and the same total-caloric intake as the other two diets for lunch with red wine, 32-35 energy-% from carbohydrates) in a randomized cross-over design. Total-caloric intake/test-day at the clinic from food was 1025-1080 kCal in men and 905-984 kCal in women. The test meals were consumed at a diabetes ward under supervision. less thanbrgreater than less thanbrgreater thanResults: Twenty-one participants were recruited and 19 completed the studies. The low-carbohydrate diet induced lower insulin and glucose excursions compared with the low-fat diet (pandlt;0.0005 for both AUC). The insulin-response following the single Mediterranean-style lunch-meal was more pronounced than during the low-fat diet lunch (insulin increase-ratio of the low-fat diet: 4.35 +/- 2.2, of Mediterranean-style diet: 8.12 +/- 5.2, p=0.001) while postprandial glucose levels were similar. The increase-ratio of insulin correlated with the elevation of the incretin glucose-dependent insulinotropic-polypeptide following the Mediterranean-style diet lunch (Spearman, r = 0.64, p = 0.003). less thanbrgreater than less thanbrgreater thanConclusions: The large Mediterranean-style lunch-meal induced similar postprandial glucose-elevations as the low-fat meal despite almost double amount of calories due to a pronounced insulin-increase. This suggests that accumulation of caloric intake from breakfast and lunch to a single large Mediterranean style lunch-meal in NIDDM might be advantageous from a metabolic perspective.

AIMS/HYPOTHESIS: The study aimed to compare the effects of a 2 year intervention with a low-fat diet (LFD) or a low-carbohydrate diet (LCD), based on four group meetings to achieve compliance. METHODS: This was a prospective randomised parallel trial involving 61 adults with type 2 diabetes consecutively recruited in primary care and randomised by drawing ballots. Patients that did not speak Swedish could not be recruited. The primary outcomes in this non-blinded study were weight and HbA(1c). Patients on the LFD aimed for 55-60 energy per cent (E%) and those on LCD for 20 E% from carbohydrate. RESULTS: The mean BMI and HbA(1c) of the participants were 32.7 ± 5.4 kg/m(2) and 57.0 ± 9.2 mmol/mol, respectively. No patients were lost to follow-up. Weight loss did not differ between groups and was maximal at 6 months: LFD -3.99 ± 4.1 kg (n = 31); LCD -4.31 ± 3.6 kg (n = 30); p < 0.001 within groups. At 24 months, patients on the LFD had lost -2.97 ± 4.9 kg and those on LCD -2.34 ± 5.1 kg compared with baseline (p = 0.002 and p = 0.020 within groups, respectively). HbA(1c) fell in the LCD group only (LCD at 6 months -4.8 ± 8.3 mmol/mol, p = 0.004, at 12 months -2.2 ± 7.7 mmol/mol, p = 0.12; LFD at 6 months -0.9 ± 8.8 mmol/mol, p = 0.56). At 6 months, HDL-cholesterol had increased with the LCD (from 1.13 ± 0.33 mmol/l to 1.25 ± 0.47 mmol/l, p = 0.018) while LDL-cholesterol did not differ between groups. Insulin doses were reduced in the LCD group (0 months, LCD 42 ± 65 E, LFD 39 ± 51 E; 6 months, LCD 30 ± 47 E, LFD 38 ± 48 E; p = 0.046 for between-group change). CONCLUSIONS/INTERPRETATION: Weight changes did not differ between the diet groups, while insulin doses were reduced significantly more with the LCD at 6 months, when compliance was good. Thus, aiming for 20% of energy intake from carbohydrates is safe with respect to cardiovascular risk compared with the traditional LFD and this approach could constitute a treatment alternative. TRIAL REGISTRATION: ClinicalTrials.gov NCT01005498 FUNDING: University Hospital of Linköping Research Funds, Linköping University, the County Council of Östergötland, and the Diabetes Research Centre of Linköping University.