Effects of a palaeolithic diet on obstructive sleep apnoea occurring in females who are overweight after menopause-a randomised controlled trial.

BACKGROUND/OBJECTIVES: Obesity is the main risk factor for obstructive sleep apnoea, commonly occurring in females who are overweight after menopause. We aimed to study the effect of a palaeolithic diet on sleep apnoea in females with overweight after menopause from the population. METHODS: Seventy healthy, non-smoking females with a mean age of 60 years and a mean BMI of 33 kg/m2 were randomised to a palaeolithic diet or to a control low-fat diet according to Nordic Nutritional Recommendations, for 2 years. The apnoea-hypopnoea index was measured and daytime sleepiness was estimated during the intervention. RESULTS: The mean apnoea-hypopnoea index at baseline was 11.6 (95% CI 8.6-14.5). The mean weight loss was 7.2 kg (95% CI 5.3-9.2 kg) in the palaeolithic diet group and 3.9 kg in the control group (95% CI 1.9-5.9 kg); p < 0.021 for the group difference. The reduction in weight corresponded to a reduction in the apnoea-hypopnoea index in the palaeolithic diet group (r = 0.38, p = 0.034) but not in the control group (r = 0.08, p = 0.69). The apnoea-hypopnoea index was reduced in the palaeolithic diet group when the weight was reduced by more than 8 kg. Daytime sleepiness according to the Epworth Sleepiness Scale score and the Karolinska Sleepiness Scale score was unaffected by dietary group allocation. CONCLUSIONS: A substantial decrease in body weight of 8 kg was needed to achieve a reduction in sleep apnoea in this small trial of women who are overweight after menopause. The palaeolithic diet was more effective for weight reduction than a control low-fat diet and the reduction in sleep apnoea was related to the degree of weight decrement within this diet group. TRIAL REGISTRATION: Clinicaltrials.gov: NCT00692536.

Decreased lipogenesis-promoting factors in adipose tissue in postmenopausal women with overweight on a Paleolithic-type diet.

PURPOSE: We studied effects of diet-induced postmenopausal weight loss on gene expression and activity of proteins involved in lipogenesis and lipolysis in adipose tissue. METHODS: Fifty-eight postmenopausal women with overweight (BMI 32.5 ± 5.5) were randomized to eat an ad libitum Paleolithic-type diet (PD) aiming for a high intake of protein and unsaturated fatty acids or a prudent control diet (CD) for 24 months. Anthropometry, plasma adipokines, gene expression of proteins involved in fat metabolism in subcutaneous adipose tissue (SAT) and lipoprotein lipase (LPL) activity and mass in SAT were measured at baseline and after 6 months. LPL mass and activity were also measured after 24 months. RESULTS: The PD led to improved insulin sensitivity (P < 0.01) and decreased circulating triglycerides (P < 0.001), lipogenesis-related factors, including LPL mRNA (P < 0.05), mass (P < 0.01), and activity (P < 0.001); as well as gene expressions of CD36 (P < 0.05), fatty acid synthase, FAS (P < 0.001) and diglyceride acyltransferase 2, DGAT2 (P < 0.001). The LPL activity (P < 0.05) and gene expression of DGAT2 (P < 0.05) and FAS (P < 0.05) were significantly lowered in the PD group versus the CD group at 6 months and the LPL activity (P < 0.05) remained significantly lowered in the PD group compared to the CD group at 24 months. CONCLUSIONS: Compared to the CD, the PD led to a more pronounced reduction of lipogenesis-promoting factors in SAT among postmenopausal women with overweight. This could have mediated the favorable metabolic effects of the PD on triglyceride levels and insulin sensitivity.

Postprandial levels of GLP-1, GIP and glucagon after 2 years of weight loss with a Paleolithic diet: a randomised controlled trial in healthy obese women.

Objective To investigate how weight loss by different diets impacts postprandial levels of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and glucagon. Methods In this single-centre, parallel group 2-year trial, 70 healthy postmenopausal obese women were randomised to the Paleolithic diet or a healthy control diet based on Nordic Nutrition Recommendations. Both diets were without calorie restriction. The primary outcome was the change in fat mass. Here, secondary analyses on GLP-1, GIP and glucagon measured during an OGTT are described. Results In the Paleolithic diet group, mean weight loss compared to baseline was 11% at 6 months and 10% at 24 months. In the control diet group, mean weight loss was 6% after 6 and 24 months (P = 0.0001 and P = 0.049 for the comparison between groups at 6 and 24 months respectively). Compared to baseline, the mean incremental area under the curve (iAUC) for GLP-1 increased by 34 and 45% after 6 and 24 months in the Paleolithic diet group and increased by 59% after 24 months in the control diet group. The mean iAUC for GIP increased only in the Paleolithic diet group. The area under the curve (AUC) for glucagon increased during the first 6 months in both groups. The fasting glucagon increase correlated with the ß-hydroxybutyrate increase. Conclusions Weight loss caused an increase in postprandial GLP-1 levels and a further rise occurred during weight maintenance. Postprandial GIP levels increased only after the Paleolithic diet. Reduced postprandial glucagon suppression may be caused by a catabolic state.

Attenuated Low-Grade Inflammation Following Long-Term Dietary Intervention in Postmenopausal Women with Obesity.

OBJECTIVE: Abdominal fat accumulation after menopause is associated with low-grade inflammation and increased risk of metabolic disorders. Effective long-term lifestyle treatment is therefore needed. METHODS: Seventy healthy postmenopausal women (age 60 ± 5.6 years) with BMI 32.5 ± 5.5 were randomized to a Paleolithic-type diet (PD) or a prudent control diet (CD) for 24 months. Blood samples and fat biopsies were collected at baseline, 6 months, and 24 months to analyze inflammation-related parameters. RESULTS: Android fat decreased significantly more in the PD group (P = 0.009) during the first 6 months with weight maintenance at 24 months in both groups. Long-term significant effects (P < 0.001) on adipose gene expression were found for toll-like receptor 4 (decreased at 24 months) and macrophage migration inhibitory factor (increased at 24 months) in both groups. Serum interleukin 6 (IL-6) and tumor necrosis factor α levels were decreased at 24 months in both groups (P < 0.001) with a significant diet-by-time interaction for serum IL-6 (P = 0.022). High-sensitivity C-reactive protein was decreased in the PD group at 24 months (P = 0.001). CONCLUSIONS: A reduction of abdominal obesity in postmenopausal women is linked to specific changes in inflammation-related adipose gene expression.

Left ventricular remodelling changes without concomitant loss of myocardial fat after long-term dietary intervention.

BACKGROUND: Accumulation of myocardial triglycerides (MTG) is associated with impaired left ventricular (LV) remodelling and function in obese and diabetic subjects. The role of MTG accumulation in development of heart failure in this group of patients is unknown. Short-term studies suggest that diets that lead to weight loss could mobilize MTG, with a favourable effect on cardiac remodelling. In a 24-month, randomized, investigator-blinded study, we assessed the effect of two different diets and subsequent weight loss on cardiac function and MTG in postmenopausal women. METHODS: Sixty-eight healthy postmenopausal women with body mass index [BMI] ≥27kg/m(2) were randomized to an ad libitum Palaeolithic diet (PD) or a Nordic Nutrition Recommendation (NNR) diet for 24months. Morphology, cardiac function, and MTG levels were measured using magnetic resonance (MR) scanning, including proton spectroscopy at baseline and 6 and 24months. RESULTS: Despite mean weight losses of 4.9 (1.0) kg (NNR) and 7.8 (1.1) kg (PD), the MTG content did not change over time (p=0.98 in the NNR and p=0.11 in the PD group at 24months). Reduced left ventricular mass was observed in both diet groups over 24months. Blood pressure was reduced at 6months, but returned to baseline levels at 24months. End diastolic volume, stroke volume, and cardiac output decreased over time. No differences between diet groups were observed. CONCLUSIONS: Diet intervention and moderate weight loss over 24months improved LV remodelling but did not alter MTG levels in overweight/obese postmenopausal women.