Dose-response effects of dietary marine oil on carbohydrate and lipid metabolism in normal subjects and patients with hypertriglyceridemia.
Recent studies indicate that marine (omega-3) fatty acids decrease hypertriglyceridemia but worsen hyperglycemia in diabetes. We studied dose-response relationships between omega-3 intake and indices of carbohydrate and lipid metabolism in 21 hypertriglyceridemic patients with (n = 6) or without (n = 15) diabetes, and 6 normal volunteers. All subjects consumed isocaloric diets of 65% carbohydrate, 20% fat, and 15% protein. The basal diet contained 15% of total calories as vegetable oil (omega-6), and the test diets included 15%, 7.5%, or 3.75% calories as fish oil (MaxEPA). After three months of the basal diet, patients were randomized to receive two 3-month omega-3 diets in the following sequences: 15%/7.5%, 7.5%/15%, 7.5%/3.75%, or 3.75%/7.5%. Both 15% and 7.5% diets, regardless of sequence, significantly decreased serum triglycerides but increased low-density lipoprotein (LDL)-cholesterol levels as much as 98% and LDL/high-density lipoprotein (HDL)-cholesterol ratio as much as 1.6-fold. Daily insulin requirements of three diabetic patients increased progressively while they received an omega-3-enriched diet for up to 2 years. In healthy controls, favourable changes induced by an omega-3 fatty acid diet in serum lipids and lipoproteins were associated with a tendency toward an inhibition of C-peptide secretion following a meal challenge. We conclude that substitution of commercially available omega-3 for omega-6 fatty acids improves hypertriglyceridemia but may worsen other lipoproteins indices and may increase insulin requirements in diabetic hypertriglyceridemic subjects.
Stacpoole
P W
PW
Department of Medicine, University of Florida College of Medicine, Gainesville 32610.
Alig
J
J
Ammon
L
L
Crockett
S E
SE
D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D050260:Carbohydrate Metabolism; D008076:Cholesterol, HDL / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000378:metabolism; D004032:Diet; D004305:Dose-Response Relationship, Drug; D002149:Energy Intake; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage* / Q000494:pharmacology; D005260:Female; D005395:Fish Oils / Q000008:administration & dosage*; D005951:Glucose Tolerance Test; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood / Q000150:complications / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000378:metabolism
D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D015525:Fatty Acids, Omega-3; D005395:Fish Oils; D007328:Insulin; D014280:Triglycerides