Singapore: The popularity of coconut oil has risen in recent years, this has been attributed to its suggested health benefits -- preventing heart disease, strengthening the immune system, reducing belly fat, and staving off dementia. Now, a recent review published in the AHA journal Circulation has found coconut oil consumption to be associated with significantly higher LDL-cholesterol than nontropical vegetable oils. High LDL-cholesterol or bad cholesterol increases the risk of cardiovascular diseases (CVDs).
Coconut oil is known to be high in saturated fat and may, therefore, raise serum cholesterol concentrations but beneficial effects on other cardiovascular risk factors have also been suggested. Therefore, Nithya Neelakantan, the National University of Singapore and National University Health System, Singapore, and colleagues conducted a systematic review of the effect of coconut oil consumption on blood lipids and other cardiovascular risk factors compared with other cooking oils using data from clinical trials.
For the purpose, the researchers searched online databases through June 2019. The trials that compared the effects of coconut oil consumption with other fats that lasted at least 2 weeks were selected. Two reviewers independently screened articles, extracted data, and assessed the study quality according to the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A total of 16 articles were included in the meta-analysis.
The main outcomes included low-density lipoprotein cholesterol (LDL-cholesterol), high-density lipoprotein cholesterol (HDL-cholesterol), total cholesterol, triglycerides, measures of body fatness, markers of inflammation, and glycemia. Results were available from all trials on blood lipids, 8 trials on body weight, 5 trials on percentage body fat, 4 trials on waist circumference, 4 trials on fasting plasma glucose, and 5 trials on C-reactive protein.
Key findings of the study include:
Coconut oil consumption significantly increased LDL-cholesterol by 10.47 mg/dL (N=16) and HDL-cholesterol by 4.00 mg/dL (N=16) as compared with nontropical vegetable oils.
These effects remained significant after excluding nonrandomized trials, or trials of poor quality (Jadad score <3).
Coconut oil consumption did not significantly affect markers of glycemia, inflammation, and adiposity as compared with nontropical vegetable oils.
"Coconut oil consumption results in significantly higher LDL-cholesterol than nontropical vegetable oils. This should inform choices about coconut oil consumption," concluded the authors.
The study, "The Effect of Coconut Oil Consumption on Cardiovascular Risk Factors: A Systematic Review and Meta-Analysis of Clinical Trials," is published in the journal Circulation.
DOI: https://doi.org/10.1161/CIRCULATIONAHA.119.043052