Low Carbohydrate Portfolio or "Eco-Atkins" Diet
Exchange of the butter, eggs, cheese and meat in the Atkins diet for soy protein foods, other vegetable proteins including gluten and vegetable fats, nuts, avocado, olive and canola oil will result in dramatic rather than modest reductions in blood lipids with weight loss. In effect this will represent an exchange of saturated fat and animal protein for healthy monounsaturated and polyunsaturated fats and vegetable proteins with significant effects on blood lipids while still encouraging weight loss.
Other: Eco-Atkins diet (high vegetable protein and vegetable fat)
Other: NCEP diet
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind
Primary Purpose: Treatment
|Official Title:||Low Carbohydrate Portfolio or "Eco-Atkins" Diet|
- total and low-density lipoprotein (LDL) cholesterol
- LDL:HDL cholesterol ratio
- weight reduction
- blood pressure
- high-density lipoprotein (HDL) cholesterol
- HDL2 and HDL3, triglyceride, apolipoprotein A1 and B, Lp(a) and LDL particle size
- glucose, insulin and measurements of oxidative stress
|Study Start Date:||April 2005|
|Estimated Study Completion Date:||December 2006|
|Experimental: Eco-Atkins diet||Other: Eco-Atkins diet (high vegetable protein and vegetable fat)|
|Active Comparator: NCEP diet||Other: NCEP diet|
Subjects: Thirty overweight hyperlipidemic subjects who wish to lose weight.
- Protocol (Metabolic Study): will be randomized to either the Eco-Atkins diet (15 subjects) or NCEP diet (15 subjects). The diets will be provided for the one month period with the aim of inducing the same weight loss (5 kg) as seen in the first month of the published reports on the Atkins diet. The diets will provide about 60% of estimated energy requirements. Subjects will be provided with their diets at weekly intervals by courier and intakes adapted to ensure that they achieve their target weight loss goal. Fasting weight will be taken at weekly intervals together with blood pressure and blood for lipids, glucose and insulin assessment.
- Protocol (Ad Libitum Study): After completing the metabolic phase of the study, the thirty subjects will be asked to continue with the diet to which they were randomized for a further 6-month period. During this ad libitum trial, study foods will not be provided. This longer less tightly controlled study will establish the value of this diet in "real life" situations. This will be required to support our shorter term, well-controlled more detailed metabolic study. Fasting weight will be taken at monthly intervals together with blood pressure and blood for lipids, glucose and insulin assessment.
Study Details: Participants will come after a 12h overnight fast to the Risk Factor Modification Centre 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 metabolic study and monthly during the ad libitum study. Prior to the start of the study, participants 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 participants have been seated for at least 20 minutes. Height (in cm) will be recorded at the first visit. Body composition measurements will be measured using bioelectric impedance at baseline and week 4 of the metabolic phase, and months 3 and 6 of the ad libitum phase. Throughout the study period, participants will maintain the diet prescribed on their initial visit. At each visit, participants will provide a fasting blood sample and seven-day food records will be collected. During the last week of the metabolic and ad libitum study, 24h fecal and urine collections will be completed.
|Risk Factor Modification Centre, St. Michael's Hospital|
|Toronto, Ontario, Canada, M5C 2T2|
|Principal Investigator:||David JA Jenkins, MD, PhD, DSc||University of Toronto and St. Michael's Hospital|