DIET, HEART DISEASE AND PALM OIL
EMERGING EVIDENCE SUGGESTS
A COMPLEX RELATIONSHIP
Palm oil is one of the 17 edible oils cited by Codex Alimentarius, Food and Agriculture Organization (FAQ) and the World Health Organization (WHO) as an edible oil suitable for human consumption.
As an oil of plant origin, palm oil is cholesterol free. It has a balanced fatty acid composition – saturated (palmitic 45% and stearic 4%) and unsaturated fatty acids (oleic 40% and linoleic 10%) as shown in Figure 1.
Figure 1. Fatty Acid Composition of Common Edible Oils
Palm oil has a high content of Vitamin E, both tocopherols and tocotrienols. Crude as well as red palm oil are also rich sources of provitamin A carotenoids. These constituents in palm oil help in promoting a healthy lifestyle.
Historically, dietitians and clinicians perceived that due to its relatively high levels of saturated fatty acids, palm oil would have a negative effect on coronary heart disease risk by virtue of its effects on the lipid profile. However, recent research findings have challenged this perception. While palm oil’s effects on serum lipids are variable, some studies show beneficial effects of palm oil on HDL. Meta-analyses showed no effect of palm oil on the ratio of TC/HDL-C. In fact, palm oil’s effects on TC/HDL-C are similar to that of olive oil.
Diets rich in palm oil did not significantly change the TC/HDL or LDL/HDL cholesterol ratios (Fattore et al., 2014)
Additionally, several meta-analyses have found no evidence that reduction in saturated fat consumption reduces cardiovascular disease risk (Table 1). Therefore, the basis for consistently recommending a diet low in saturated fat remains unclear.
Table 1. Findings on Saturated Fat and Heart Disease
| Reference | Author’s conclusion |
| Siri-Tarino et al., 2010 | No significant evidence that saturated fatty acids are associated with increased risk of coronary heart disease |
| Chowdhury et al., 2014 | No association with dietary or circulating saturated fatty acids with coronary heart disease |
| de Souza et al., 2015 | Saturated fatty acids are not associated with all-cause mortality or coronary heart disease |
| Harcombe et al., 2017 | No significant association between coronary heart disease deaths and saturated fat consumption |
| Marangoni et al., 2017 | There is no evidence on the specific health effects of palm oil consumption as compared with other SFA-rich fats |
Palm olein reduces cholesterol as effectively as olive, canola and rapeseed oils
In Malaysia, saturated fatty acid consumption is about 14% of total energy intake, contributed by a variety of foods including palm oil as the major dietary oil. Study by Karupaiah et al., (2019) showed that total fat consumption has little-to-no impact on heart disease lipid-lipoprotein biomarkers. These markers are influenced more by the Malaysian dietary carbohydrate content. Thus, based on these emerging evidence, our traditional understanding of how diet impacts risk factors for heart disease and other chronic illnesses needs to be reassessed. Future research needs to focus on the role of dietary patterns and how specific foods (e.g. palm oil) fit into these patterns.
References
- Fattore E, Bosetti C, Brighenti F, Agostoni C et al. (2014). The American Journal of Clinical Nutrition. 99(6): 1331-1350.
- Siri-Tarino PW, Sun Q, Hu FB and Krauss RM. (2010). The American Journal of Clinical Nutrition. 91(3): 535-546.
- Chowdury R, Warnakula S, Kunutsor S, Crowe F et al. (2014). Annals of Internal Medicine. 160(6): 398-406.
- de Souza RJ, Mente A, Maroleanu A, Cozma AI et al. (2015). The British Medical Journal. 351: 3978-3992.
- Harcombe Z, Baker JS and Davies B. (2017). British Journal of Sports Medicine. 51(24): 1743-1749.
- Marangoni F, Galli C, Ghiselli A, Lercker G et al. (2017). International Journal of Food Sciences and Nutrition. 68(6): 643-655.
- Karupaiah T, Chuah KA, Chinna K, Pressman P et al. (2019). Scientific Reports. 9(1):1-13.
