Does Palm Oil Cause Hypertension?

Palm oil is often labelled as harmful, particularly in the West. Despite being consumed as a staple in Africa and parts of Asia for centuries, it has remained at the centre of controversy over its potentially harmful effects on heart health. Palm oil contains saturated fat, which gives it its semi-solid consistency at room temperature. Because saturated fatty acids have been linked to cardiovascular disease, many people wonder: does palm oil cause hypertension? Let's take a closer look at what science says.

Does Palm Oil Cause High Blood Pressure?

A meta-analysis conducted by Odia et al. (2015) found no clear evidence that palm oil is atherogenic. Much of the concern stems from the fact that palm oil contains palmitic acid, the saturated fatty acid responsible for its semi-solid form. However, another widely consumed fat, butter, contains an even higher proportion of saturated fatty acids than palm oil, yet it has not received the same level of controversy.

Moreover, palm oil also contains oleic acid and linoleic acid, which are monounsaturated and polyunsaturated fatty acids, respectively. In a preclinical study, red palm oil inhibited the rise of blood pressure and improved blood lipid profile in hypertensive rats. The study showed that moderate consumption of red palm oil may delay the onset and suppress the progression of hypertension.

Red palm oil is also a rich source of vitamins A and E as well as phenols, which are powerful antioxidants that help the body fight inflammation associated with plaque build-up in the bloodstream. In a recent study, high doses of palm oil phenolics (1,000 and 1,500 mg/day) were reported to reduce both systolic and diastolic blood pressure. The study also found significant improvements in total antioxidant capacity, which is inversely associated with elevated blood pressure. By neutralising harmful free radicals, these antioxidants may contribute to better blood pressure regulation.

In another preclinical study, fresh palm oil caused no significant changes in blood pressure. However, it was compared with diets containing palm oil that had been reheated five and ten times, respectively. The study reported progressively higher blood pressure with increasing heating cycles. For normal household use, repeatedly overheating palm oil is not advisable, as it can lead to health problems, just as repeatedly heated cooking oils generally do.

Palm oil is highly versatile and is widely used in industrial food production. Overly processed palm oil is particularly common in industrial frying and in the manufacture of ultra-processed foods. Excessive processing is a concern for virtually all foods because it significantly alters their natural composition and may contribute to adverse health outcomes.

The Changing Narrative

There is now growing evidence supporting some of the health benefits of palm oil, making it increasingly difficult to dismiss outright. Palm oil is used in an exceptionally wide range of products, and its versatility is unmatched. For example, oil palm plantations can produce more than 3,700 litres of oil per hectare, compared with approximately 1,600 litres from olive trees on the same land area.

As a result, the debate is gradually shifting away from the health effects of palm oil consumption and towards its environmental and social implications. The World Wide Fund for Nature argues that palm oil plantations contribute to deforestation and pose a major threat to forest biodiversity. The organisation also notes that although the industry provides employment for millions of people, including smallholder farmers, it remains poorly regulated in many regions, leaving workers vulnerable to exploitation.

However, these challenges are not unique to palm oil. Large-scale agricultural production of many crops can also have significant environmental and social consequences. The environmental impact of commercial agriculture should therefore continue to receive careful attention, and initiatives such as the Rainforest Alliance and the Roundtable on Sustainable Palm Oil (RSPO) provide important opportunities to promote more sustainable palm oil production.