Health impacts of red palm oil, the lesser-known sister of refined palm oil

Image: Left, reddish palm oil made from the pulp of oil palm fruit. Right, clear palm kernel oil made from the kernels. Credit: T. K. Naliaka, Wikimedia Commons, Creative Commons Attribution-Share Alike 4.0 International.

Consumption and production of palm oil have increased sharply over the past few decades, leading to concerns over deforestation and other environmental and social impacts. Refined palm oil is often seen as unhealthy because of its saturated fat content and its frequent use in many types of processed food. Its unrefined version, red palm oil, is less well known in Western countries and tends to be used in different ways to refined palm oil. Furthermore, red palm oil contains various vitamins and other components that can be beneficial to health in some contexts. This blog post will look at how the health impacts of red palm oil differ from those of refined palm oil and whether red palm oil could play a role in improving health.

Health impacts of refined palm oil

The health impacts of refined palm oil have largely been attributed to its saturated fat content. Saturated fat consumption can influence the development of non-communicable diseases (NCD), more specifically:

• Observational research suggests that people who consume more saturated fats in place of unsaturated fats tend to have higher rates of cardiovascular disease (CVD) [1-5].
• Controlled trials indicate that individuals who partially replace food sources of saturated fats with food sources of unsaturated fats, while keeping overall fat intake the same, can lower their risk of CVD by 30%, which is similar to the treatment outcomes of statin use [1].
• There is limited evidence on whether saturated fat increases cancer risk [6] (although a study has shown that saturated fatty acids can promote the growth of pancreatic cancer cells in the laboratory), and no conclusive evidence that refined palm oil specifically increases cancer risk [7-9].
• It is also worth noting that total fat intake appears to be a useful predictor of insulin sensitivity within the body, meaning that people who have a higher fat intake are more likely to experience metabolic syndrome (high blood pressure, high blood sugar, excess abdominal fat, and abnormal blood lipids) and type 2 diabetes mellitus [10-11]. When consumed in recommended amounts, refined palm oil specifically does not seem to cause any harm to glucose metabolism [12].

Another reason for refined palm oil’s connection to NCDs is that – particularly in affluent countries – it is commonly used in highly processed foods because of its useful properties, including a neutral taste, long shelf life and ability to withstand the high heat of processing [9, 13-15]. Processed foods such as margarine, biscuits, crackers, ice cream, sweets, and chocolate bars often also contain added sugars, salt, and/or refined grains, making it difficult to determine whether refined palm oil in particular makes the processed food more or less likely to contribute to a healthy diet [16-20].

The health impacts of refined palm oil also depend on which foods it may be replacing in a diet. The more that refined palm oil makes up a substantial portion of one’s dietary intake and crowds out foods such as vegetables, fruits, legumes, whole grains, nuts, seeds, cultured dairy, oils rich in polyunsaturated fats, and seafood, the less useful that dietary pattern likely is for the prevention of NCDs. This is mainly due to the variety of health-promoting effects these other foods have on the risk factors that contribute to NCDs [1, 2, 4-8, 16, 17, 20-26].

Refined palm oil has also been used to replace trans fats from partially hydrogenated vegetable oils, which are unique because they are the only category of dietary fats that have detrimental effects on all known CVD biomarkers. Consuming any other oil, including refined palm oil, in place of partially hydrogenated oils (the main source of trans fats) very likely leads to positive health outcomes, most specifically improved cardiovascular health [1, 2, 4-6, 8, 16, 17, 21, 22, 24-26].

Refined palm oil appears to be a better option than coconut oil from the perspective of lowering risk factors for CVD [27].

Health impacts of red palm oil

Red palm oil contains the same amount of saturated fat as refined palm oil, but its different properties mean that its health impacts may be different to those of refined palm oil. Although there is a lack of direct research on the human health impacts of red palm oil consumption, some information is available from animal studies and from studies on individual components of red palm oil [9, 13, 28-32].

Red palm oil contains high levels of health-promoting compounds, such as carotenoids – which give it the red colouring – vitamins (including vitamin A from the carotenoids), phytosterols, squalene, gums, phospholipids, and CoQ10. Red palm oil could therefore be beneficial to people who do not already have other sources of those vitamins and compounds in their diets. Some of these compounds appear to offer protection against CVD [7, 9, 13, 23, 28-33].

Animal studies have shown that consumption of red palm oil might offer protection against CVD [32]. As previously mentioned, this might extend to refined palm oil, depending on what it is replacing [34].

Red palm oil is often used in traditional cooking rather than in highly processed foods. The dietary patterns with which it is associated are generally healthier than the dietary patterns with which refined palm oil consumption is typically associated [28, 32, 33, 35, 35].

Possible drawbacks of red palm oil consumption include its distinctive taste, which may not appeal to everyone, while consuming too much can cause weight gain, liver toxicity, and carotenodermia (a yellowish discolouration of the skin) [28-31, 33].

What role could red palm oil play in improving health, if any?

Since red palm oil provides a mix of nutrients, some of which can harm health and some of which can be beneficial, promoting red palm oil in a way that is beneficial overall requires careful consideration of the specific context.

Using red palm oil in processed foods

It is unlikely that red palm oil can be incorporated into processed foods because its taste, smell, colour, and shelf life are different from the refined version. Plus, the health-promoting compounds may be degraded by processing [7, 15, 28, 37-40].

Furthermore, incorporating red palm oil into processed foods without otherwise changing their formulation is likely to have limited health benefits because they would still contain high amounts of salt, sugar, refined grains, etc. [41-47].

Replacing commonly used cooking oils

The most common oils used in the U.S. include soybean, canola, and corn (USDA). Replacing these mostly unsaturated fats with red palm oil might increase NCD risk because of the increased saturated fat content. However, one could make the argument that using red palm oil instead of soybean, canola, and corn oil could offer some protection against NCDs due to the vitamins, phytosterols, squalene, gums, phospholipids, and CoQ10 present in red palm oil [7, 9, 13, 23, 28-33].

Targeting Vitamin A deficiency in Sub-Saharan Africa and Southern Asia

One use case where the saturated fat content of red palm oil might not pose a disadvantage is in remedying vitamin A deficiency in some low-income regions.

Vitamin A deficiency is rare in the U.S. (CDC; NIH) and U.K. (BNF). However, children and pregnant or lactating women in lower-income countries are at a higher risk of vitamin A deficiency (WHO; Global Nutrition Report 2018; NIH).

Sub-Saharan Africa and Southern Asia have the highest rates of undernourishment and vitamin A deficiency. This makes red palm oil a prime candidate for public health intervention, as it could provide both necessary calories and vitamin A [48, 49]. Conveniently, oil palms tend to thrive in these geographic regions.

In conclusion, while red palm oil may offer some health benefits relative to refined palm oil, its saturated fat content means that its health impacts must be considered carefully according to context. Rather than one type of fat being best overall, the optimal sources of oil and fat will vary based on geography, culture, tradition, familiarity, and taste.

 

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