Advertisement

Topics

Lipoprotein Turnover on Low- and High-MUFA Portfolio Diets

2014-08-27 03:40:19 | BioPortfolio

Summary

Low and very low carbohydrate diets, such as the Atkins' Diet, have recently gained attention for their potential health benefits from weight loss and have gained some scientific support from a growing number of studies. Benefits have been noted in relation to raised "good" cholesterol, lower "bad" cholesterol and triglycerides. Other studies have shown an advantage in substituting vegetable fat for carbohydrate in insulin resistant individuals and in some instances in type 2 diabetes where improvements were seen in "good" cholesterol and blood sugars. At the same time, our research have been exploring diets containing less processed carbohydrates and other components which in combination (portfolio diet) have a similar cholesterol lowering effect to drug therapy.

Therefore we wish to determine whether our cholesterol-lowering components (portfolio diet) should be incorporated into lower carbohydrate diets especially to preserve "good" cholesterol and lower "bad" cholesterol for decreasing the risk of heart disease.

Description

All subjects will undergo two parallel 2-phase treatments. On one treatment, subjects will be placed on a low fat diet for one month (control run-in diet) and then for the second month will continue on the low- fat diet (i.e. low-MUFA) with the addition of the portfolio components. The order of these two phases will not be randomized. The other treatment will be similar to the above except that the background diet of the portfolio phase will be high in monounsaturated fat (high-MUFA). Subjects will be allocated randomly to either treatment. Diets will be metabolically controlled and all food will be provided at weekly intervals.

Subjects will come after a 12h overnight fast to the Risk Factor Modification Center at St. Michael's Hospital or the Department of Nutritional Sciences, University of Toronto immediately prior to commencement of each treatment phase and at weekly intervals during the course of each study period. Prior to the start of the study, subjects will be instructed on details of the study diet protocol. They will also be asked to maintain a constant level of physical activity throughout the course of the study. At all visits, body weight (in kg) will be obtained in indoor clothing, without shoes, and blood pressure will be taken twice in the dominant arm after subjects have been seated for at least 20 minutes. Height (in cm) will be recorded at the first visit. Throughout the study period, subjects will maintain the diet prescribed on their initial visit. At every other visit of each treatment phase, subjects will provide a fasting blood sample. The kinetic tests of lipoprotein metabolism will be performed during the 4th and 8th week of the study. At baseline and during the last week of each study phase, 24h urine collection and 12h breath hydrogen collections will be completed.

The measurement of apolipoprotein in vivo kinetics will be carried out using a primed-constant infusion of [D3]L-leucine. This protocol allows for the determination of the kinetics of all apolipoproteins simultaneously. Kinetics studies will be conducted in the constantly fed state where participants receive 1/30th of their daily energy requirements every half-hour for the whole duration of the test (15 hours). These methods are described in detail in previous publications from our group. Briefly, at 7am on the morning of the study, after a 12-hour overnight fast, participants will be admitted to the Toronto General Hospital Clinical Investigation Unit and two intravenous catheters (IV's) will be inserted, one into each forearm vein. One IV will be for infusion of the stable isotope described below and one for withdrawal of blood samples. After achieving a steady state (3hrs after the small half-hourly meals), subjects will first receive a bolus injection of 10 µmol/kg of body weight of [D3]L-leucine ([D3]L-leucine 98%, C/D/N Isotopes) dissolved in physiological saline (0.9% NaCl) and then a constant infusion of 10 µmol/kg/h of [D3]L-leucine for 12 hours via an intravenous line inserted into a left forearm vein. Blood samples will be collected at regular intervals (0, 1/2, 1, 2, 4, 6, 8, 10, 11, 12hrs). All lipoprotein subfractions will be separated by sequential ultracentrifugation and frozen thereafter at -80oC until they are processed for analysis.

Study Design

Allocation: Randomized, Control: Active Control, Intervention Model: Parallel Assignment, Masking: Single Blind, Primary Purpose: Treatment

Conditions

Hyperlipidemia

Intervention

low or high MUFA portfolio diets

Location

Risk Factor Modification Centre, St. Michael's Hospital
Toronto
Ontario
Canada
M5C 2T2

Status

Active, not recruiting

Source

University of Toronto

Results (where available)

View Results

Links

Published on BioPortfolio: 2014-08-27T03:40:19-0400

Clinical Trials [311 Associated Clinical Trials listed on BioPortfolio]

Effects of a Portfolio Diet on NAFLD in Type 2 Diabetic Patients

Patients with type 2 diabetes and non-alcoholic fatty liver disease will be enrolled. According to a parallel design, the participants will be randomized to a Portfolio diet or a monounsa...

The Combined Portfolio Diet and Exercise Study

The purpose of this study is to determine whether a dietary portfolio of cholesterol-lowering foods (viscous fibres, soy protein, plant sterols and nuts) further enhanced by increased leve...

The Effect of Strawberries in a Cholesterol-Lowering Dietary Portfolio

The purpose of this study is to determine whether addition of strawberries to a dietary portfolio of cholesterol-lowering foods will improve compliance and so increase the effectiveness of...

Effect of High Monounsaturated Fat Diet on Glycemic Control and Cardiovascular Risk Factors in Type 2 Diabetes

The purpose of this proposed randomized, controlled trial is to compare the effects of high monounsaturated fat diets and high carbohydrate diets on body weight, body composition, glycemic...

Portfolio 5 - Multicentre

The purpose of this trial is to re-evaluate the potential role of diet in modulating cardiovascular risk factors. If potent lipid-lowering effects through novel dietary interventions can b...

PubMed Articles [12558 Associated PubMed Articles listed on BioPortfolio]

Concurrent credit portfolio losses.

We consider the problem of concurrent portfolio losses in two non-overlapping credit portfolios. In order to explore the full statistical dependence structure of such portfolio losses, we estimate the...

Effect of antiretroviral therapy use and adherence on the risk of hyperlipidemia among HIV-infected patients, in the highly active antiretroviral therapy era.

HIV-infected patients exposed to antiretroviral therapy (ART) have an increased risk for hyperlipidemia and cardiovascular disease. We performed a longitudinal, comprehensive, and population-based stu...

Feeding sunflower cake from biodiesel production to Santa Ines lambs: Physicochemical composition, fatty acid profile and sensory attributes of meat.

The aim of this study was to determine the effect of the inclusion of sunflower cake in the diets of lambs on meat quality. Forty male, uncastrated Santa Ines lambs with an initial average body weight...

Effects of barley variety, dietary fiber and β-glucan content on bile acid composition in cecum of rats fed low- and high-fat diets.

Diet-induced obesity and insulin resistance have been linked to changes in bile acid (BA) profiles, which in turn are highly dependent on the dietary composition and activity of the gut microbiota. Th...

Central xanthoma of the mandible associated with hyperlipidemia: A rare presentation.

Xanthoma is a common, self-limiting cutaneous lesion of non-Langerhans cell, lipid-laden foamy histiocytes that is often concomitant with hyperlipidemia. The intraosseous counterpart is rarely encount...

Medical and Biotech [MESH] Definitions

Food and dietary formulations including elemental (chemically defined formula) diets, synthetic and semisynthetic diets, space diets, weight-reduction formulas, tube-feeding diets, complete liquid diets, and supplemental liquid and solid diets.

Rare and often fatal drug complication which affects patients undergoing long-term treatment with high doses of PROPOFOL. It is characterized by METABOLIC ACIDOSIS; HYPERLIPIDEMIA; RHABDOMYOLYSIS; cardiovascular CIRCULATORY COLLAPSE; CARDIAC FAILURE; and KIDNEY FAILURE.

The art or practice of cooking. It includes the preparation of special foods for diets in various diseases.

Diets which become fashionable, but which are not necessarily nutritious.(Lehninger 1982, page 484)

The art or practice of preparing food. It includes the preparation of special foods for diets in various diseases.

More From BioPortfolio on "Lipoprotein Turnover on Low- and High-MUFA Portfolio Diets"

Advertisement
Quick Search
Advertisement
Advertisement

 

Relevant Topics

Nutrition
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...

Cholesterol
Cholesterol is a waxy steroid metabolite found in the cell membranes and transported in the blood plasma. It is an important structural component of mammalian cell membranes, where it is establishes proper membrane permeability and fluidity. Cholesterol ...


Searches Linking to this Trial