Another interesting study highlighting the badness of low fat/high carb
diets --
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12499321&dopt=Abstract
Am J Clin Nutr 2003 Jan;77(1):43-50 Related Articles, Links
Click here to read
Hepatic de novo lipogenesis in normoinsulinemic and
hyperinsulinemic subjects consuming high-fat, low-carbohydrate and
low-fat, high-carbohydrate isoenergetic diets.
Schwarz JM, Linfoot P, Dare D, Aghajanian K.
Department of Nutritional Sciences and Toxicology, University of
California, Berkeley 94720-3104, USA. [log in to unmask]
BACKGROUND: Hypertriglyceridemia is associated with increased risk
of cardiovascular disease. Until recently, the importance of hepatic de
novo lipogenesis (DNL) in contributing to hypertriglyceridemia was
difficult to assess because of methodologic limitations. OBJECTIVE: We
evaluated the extent of the contribution by DNL to different conditions
associated with hypertriglyceridemia. DESIGN: After 5 d of an
isoenergetic high-fat, low-carbohydrate diet, fasting DNL was measured
in normoinsulinemic (<or= 85 pmol/L) lean (n = 9) and obese (n = 6) and
hyperinsulinemic (>or= 115 pmol/L) obese (n = 8) subjects. Fasting DNL
was measured after a low-fat, high-carbohydrate diet in normoinsulinemic
lean (n = 5) and hyperinsulinemic obese (n = 5) subjects. Mass
isotopomer distribution analysis was used to measure the fraction of
newly synthesized fatty acids in VLDL-triacylglycerol. RESULTS: With the
high-fat, low-carbohydrate diet, hyperinsulinemic obese subjects had a
3.7-5.3-fold higher fractional DNL (8.5 +/- 0.7%) than did
normoinsulinemic lean (1.6 +/- 0.5%) or obese (2.3 +/- 0.3%) subjects.
With the low-fat, high-carbohydrate diet, normoinsulinemic lean and
hyperinsulinemic obese subjects had similarly high fractional DNL (13
+/- 5.1% and 12.8 +/- 1.4%, respectively). Compared with baseline,
consumption of the high-fat, low-carbohydrate diet did not affect
triacylglycerol concentrations. However, after the low-fat,
high-carbohydrate diet, triacylglycerols increased significantly and DNL
was 5-6-fold higher than in normoinsulinemic subjects consuming a
high-fat diet. The increase in triacylglycerol after the low-fat,
high-carbohydrate diet was correlated with fractional DNL (P < 0.01),
indicating that subjects with high DNL had the greatest increase in
triacylglycerols. CONCLUSIONS: These results support the concept that
both hyperinsulinemia and a low-fat diet increase DNL, and that DNL
contributes to hypertriglyceridemia.
Namaste, Liz
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