An interventional study of Low-Carbohydrate Diet and Low-Fat Diet in Obesity and Insulin Resistance, sponsored by Stanford University. Completed at 1 site in United States. Open to participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2023-02-22.
Sponsored by Stanford University · Not applicable, Interventional, and Prevention
The traditional weight loss diet recommended by health professionals has been a low-fat, high-carbohydrate, calorie restricted diet. This recommendation has been challenged by a number of alternative dietary strategies, particularly low-carbohydrate diets. In several recent weight loss studies insulin resistant adults had more success with low- vs. high-carbohydrate diets, in contrast to insulin sensitive adults who had either more success or comparable success with the low-fat diets. The investigators enrolled 61 people with a wide range of insulin sensitivity/resistance. After determining their insulin resistance status, the investigators will split them in the middle and randomly assign them to one of four groups for six months: (1) Low-Carbohydrate/Insulin Resistant (LC/IR); (2) Low-Carbohydrate/Insulin Sensitive (LC/IS); (3) Low-Fat/Insulin Resistant (LF/IR); and (4) Low-Fat/Insulin Sensitive (LF/IS) (15 people/group). After 6 months the participants will switch diet for the following 6 months, i.e. those randomized to the Low-Carbohydrate diet will switch to the Low-Fat diet and vice-versa. The primary outcome of this study is to determine whether weight loss success can be increased if one follows the dietary approach appropriately matched to their insulin resistance status. Secondary outcomes include fasting insulin, glucose, lipids, and fatty acid composition.
--------------------------------------------------------------------------------
The investigators hope to learn whether matching the weight loss diet to one's insulin resistance status will increase weight loss the success. The relevance of these findings is highlighted by the fact that the national recommendations for weight loss are to follow a high-carbohydrate, low-fat diet. This would imply that about half the population has been given the wrong advice in regards to the most successful dietary pattern for weight loss.
Plasma fatty acid composition patterns have been shown to be associated with both insulin resistance and/or carbohydrate intake. As secondary analyses, the investigators will explore: (1) differences in plasma fatty acid composition between insulin sensitive and resistant participants at baseline; (2) the correlations between insulin markers and plasma fatty acid composition at baseline; (3) the interaction between insulin status and diet on 6-month changes in the plasma fatty acid composition; (4) plasma fatty acid composition changes in participants on low fat and low carbohydrate diets after 6 months; and (5) the correlations between changes in insulin markers, dietary components, and plasma fatty acid composition after 6 months.
1,960 studies on the registry are indexed under Insulin Resistance; 306 are open to participants now.
This study's enrollment of 61 is above the median of 40 across 1,536 interventional studies indexed under Insulin Resistance.
Browse Insulin Resistance studies →Stanford University is the lead sponsor of 2,117 studies on the registry; 425 are open to participants now.
Of its 259 completed or terminated interventional studies of FDA-regulated products, 197 (76%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Participants who were more insulin resistant based on the median AUC for insulin concentrations measured from OGTT prior to randomization.
Behavioral: Low-Carbohydrate Diet · Behavioral: Low-Fat Diet
Participants who were more insulin sensitive based on the median AUC for insulin concentrations measured from OGTT prior to randomization.
Behavioral: Low-Carbohydrate Diet · Behavioral: Low-Fat Diet
Counseling/instruction on how to follow a healthy low-carbohydrate diet for 6 months. One evening class/week for 8 weeks (8 total classes). Then one class every other week for 8 weeks (4 total classes). Then one class every four weeks for 8 weeks (2 total classes): 14 evening classes, total.
Counseling/instruction on how to follow a healthy low-fat diet for 6 months. One evening class/week for 8 weeks (8 total classes). Then one class every other week for 8 weeks (4 total classes). Then one class every four weeks for 8 weeks (2 total classes): 14 evening classes, total.
Change in weight
Weight change was calculated as the 12 month value minus the baseline value
Time frame: Baseline and 12 months
Change in Fasting Insulin
Fasting insulin change was calculated as the 12 month value minus the baseline value
Time frame: Baseline and 12 months
Change in insulin AUC
Insulin area under the curve (AUC) change was calculated as the 12 month value minus the baseline value.
Time frame: Baseline and 12 months
Change in Fasting Glucose
Fasting glucose change was calculated as the 12 month value minus the baseline value.
Time frame: Baseline and 12 months
Change in LDL-Cholesterol
LDL-cholesterol change was calculated as the 12 month value minus the baseline value.
Time frame: Baseline and 12 months
Change in HDL-Cholesterol
HDL-cholesterol change was calculated as the 12 month value minus the baseline value.
Time frame: Baseline and 12 months
Change in Triglycerides
Triglycerides change was calculated as the 12 month value minus the baseline value.
Time frame: Baseline and 12 months
Change in systolic and diastolic blood pressure
Blood pressure change was calculated as the 12 month value minus the baseline value.
Time frame: Baseline and 12 months
Plasma fatty acid composition at baseline
Comparison of the plasma fatty acid composition between insulin sensitive and resistant participants at baseline.
Time frame: Baseline
Correlations between insulin markers and plasma fatty acid composition at baseline.
Time frame: Baseline
Interaction between insulin status and diet on 6-month changes in the plasma fatty acid composition.
Time frame: 6 months
Comparison of plasma fatty acid composition changes in participants on low fat and low carbohydrate diets after 6 months.
Time frame: Baseline and 6 months
Correlations between changes in insulin markers, dietary components, and plasma fatty acid composition after 6 months.
Time frame: 6 months
Plan to share: No
This study is completed, as verified in Feb 2023. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Stanford University