Changes in markers for cardio-metabolic disease risk after only 1-2 weeks of a high saturated fat diet in overweight adults.
Study Goal
The researchers aimed to determine whether a short-term (1-2 weeks) high saturated fat diet could impact disease risk factors in overweight adults who typically consume a low proportion of saturated fat.
Results Summary
The study found that increasing saturated fat intake for two weeks raised LDL-cholesterol and liver damage markers (AST) but did not affect insulin resistance or blood pressure. Saturated fat accumulated in plasma and muscle lipid pools.
Population
Overweight (BMI: 27±1 kg/m²) young adults with normally low saturated fat intake (<40% of dietary fat).
Effective Dosage
Increased proportion of saturated fat from <40% to 60% of dietary fat, maintaining total fat, carbohydrate, protein, and calorie intake.
Duration
2 weeks
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat) | increase | Total plasma cholesterol concentration | overweight young adults | 148±5 vs. 164±8 mg/dl | increased | #1 |
a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat) | increase | LDL-cholesterol | overweight young adults | 78±4 vs. 95±7 mg/dl | increase | #2 |
a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat) | increase | plasma aspartate amino transferase (AST) concentration | overweight young adults | - | increased | #3 |
a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat) | no change | insulin resistance | overweight young adults | - | no change | #4 |
a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat) | no change | resting blood pressure | overweight young adults | - | no change | #5 |
a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat) | increase | proportion of SFA in plasma | overweight young adults | 35±1% vs. 39±2% | increase | #6 |
a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat) | increase | proportion of SFA in the intramyocellular triglyceride pool | overweight young adults | 32±1% vs. 37±1% | increase | #7 |
PURPOSE: Diets high in saturated fat acids (SFA) have been linked with cardio-metabolic disease risk. The purpose of this study was to determine whether only 1-2 weeks of a high SFA diet could impact disease risk factors in overweight adults who normally eat a relatively low proportion of SFA (i.e., <40% of dietary fat). METHODS: Twelve overweight (BMI: 27±1 kg/m2) young adults were studied before and after a 2-week diet that increased the proportion of SFA (<40% to 60% of dietary fat), while maintaining their daily intake of total fat, carbohydrate, protein, and calories. Insulin resistance, blood pressure, plasma markers of liver damage, total plasma cholesterol concentrations, and fatty acid profile within plasma and skeletal muscle lipid pools were assessed before and after the intervention. RESULTS: Total plasma cholesterol concentration increased (148±5 vs. 164±8 mg/dl; P<0.05) after only one week, due exclusively to an increase in LDL-cholesterol (78±4 vs. 95±7 mg/dl; P<0.05). After two weeks, plasma aspartate amino transferase (AST) concentration increased (P<0.05) but we found no change in insulin resistance, or resting blood pressure. The diet increase the proportion of SFA in plasma (35±1% vs. 39±2%; P<0.05) and the intramyocellular triglyceride pool (32±1% vs. 37±1%; P<0.05) suggesting the fatty acids in these pools may readily exchange. CONCLUSIONS: Although blood lipids remain within normal clinical range, increasing saturated fat in diet for only 2 weeks raises plasma markers of cardiovascular risk (LDL-cholesterol) and liver damage (AST). In overweight, but healthy-young adults SFA accumulate in plasma and muscle after only 1-2 weeks of dietary increase.