Snack chips fried in corn oil alleviate cardiovascular disease risk factors when substituted for low-fat or high-fat snacks.
Level 2 - randomized trial
Randomized crossover controlled feeding trial
PubMed 17556685 · doi:10.1093/ajcn/85.6.1503
What was done
In a randomized crossover trial, 33 adults completed three 25-day controlled feeding phases to evaluate the effects of different snack types on cardiovascular lipid markers. The three provided diets were: a low-fat snack diet (30.8% energy from fat, 5.2% PUFAs), a high-PUFA snack diet featuring corn-oil fried chips (36.3% energy from fat, 9.7% PUFAs), and a high-fat snack diet (37.9% energy from fat, 5.8% PUFAs).
What was found
All three diets reduced LDL and total cholesterol concentrations, but reductions were significantly greater with the low-fat and high-PUFA diets than with the high-fat diet. LDL cholesterol decreased by 12.5% on the high-PUFA diet and 11.8% on the low-fat diet, compared to 8.8% on the high-fat diet (P = 0.01 and P = 0.03, respectively). Total cholesterol decreased by 10.7% on high-PUFA and 10.5% on low-fat versus 7.9% on high-fat (P = 0.02 and P = 0.03, respectively). The high-PUFA diet showed a trend toward reducing triacylglycerol concentrations by 9.4% (P = 0.06), which was significantly greater than changes with the low-fat (P = 0.028) and high-fat (P = 0.0008) diets.
Why it matters
This study shows that the fatty acid composition of snacks is more critical than total fat restriction, demonstrating that snacks rich in polyunsaturated fats can improve lipid-related cardiovascular risk profiles.
Limits
The study had a small sample size (n = 33) and short intervention periods (25 days per phase). The abstract does not report baseline participant health status, long-term cardiovascular outcomes, or blinding procedures.