For the health-conscious, fats, particularly in the form of oil, would certainly be one of the first things to be eliminated – as much as possible anyway – from their diet.
Those more aware of the distinctions between the different types of fat might be more discriminatory by ensuring that whatever fats they do consume are of the healthier unsaturated fat, rather than the saturated variety.
While too much fat contributes to an increased risk of heart disease and obesity, too little will affect our brain, skin, hair, energy and nutrition, among others.
According to Nutrition Society of Malaysia president Dr Tee E Siong, it is recommended that fats and oils comprise 25%-30% of total energy intake for Malaysians. The recommended energy requirements for those aged above 18 range between 1,770 kcal/day and 2,240 kcal/day for the moderately active, depending on sex and age.
“Fats and oils serve as a contributor of energy – they are a concentrated source of energy (as) they are 9kcal/g versus carbohydrate and protein (both 4 kcal/g).
“Therefore, they are a very important source of energy for the population,” he said during his presentation on The Role of Palm Oil in Malaysian Diet and Health at the 2017 MPOB International Palm Oil Congress and Exhibition (Pipoc) held in Kuala Lumpur.
He added that fats are essential in the absorption and digestion of the fat-soluble vitamins A, D, E and K; provide essential fatty acids to the body; provide protection and insulation to organs; and perform various metabolic and structural functions in the body, as well as play a very important role in growth and development.
Fats also enhance the palatibility of food, and provide consistency, texture and mouthfeel, as well as satiety so that we feel full.
Said Dr Tee: “As we know, oil is a very common cooking medium.
“Even as nutritionists, we cannot be talking about poaching and blanching food all the time, we need to fry foods.
“But what oil to use (and) how much to use then becomes very important.”
He noted that palm oil in particular has served as the main source of fats and oil in the Malaysian diet for many decades.
Palm oil pros
“The unique feature of palm oil is its almost equal proportion of saturated and unsaturated fats,” Dr Tee said, adding that the monounsaturated oleic acid and polyunsaturated linoleic acid together make up about half of the fatty acids in palm oil.
Due to this feature, palm oil actually acts more like a monounsaturated fatty acid in the body and has no adverse effect on cholesterol levels, he explained.
In addition, the balance of saturated and unsaturated fats in palm oil means that it does not need to be hydrogenated to improve its thermal stability and shelf life – unlike other more unsaturated vegetable oils – and is thus, free from artificial trans-fats that increase the risk of heart disease.
“The other important feature we have to recognise, and the reason for the wide acceptance of palm oil for many users, is its good oxidative stability.
“It does not form oxidised polymers easily – this is the sticky substance that is very annoying to housewives as it sticks to the cupboards and floors and so on.
“And because of its thermal stability, it is suitable for shallow, and even, deep frying, versus other polyunsaturated fats and oils.
“So it is now recognised as the best frying oil, compared to other unsaturated oils, which tend to oxidise and break down into small compounds more easily than palm oil,” said Dr Tee.
Palm oil is also rich in phytonutrients and tocotrienols.
Phytonutrients are bioactive substances found only in plants that have many health benefits in humans.
Those found in palm oil are carotenoids, coenyzme Q10, squalene and phytosterols.
Carotenoids are primarily known for their antioxidant properties.
In addition, beta- and alpha-carotene, which form 80% of the carotenoids in palm oil, are provitamin A, which can be converted by the body into vitamin A.
“As we remember from our basic human nutrition, vitamin A is important for good eye health and the prevention of blindness; it is very important for immunity; and it also affects learning ability and mental function, particularly for children under the age of five,” said Dr Tee.
Both coenzyme Q10 and squalene also have antioxidant properties. Additionally, coenzyme Q10 is involved in the production of energy for the body, while some studies have shown that squalene may have anticancer properties.
Meanwhile, phytosterols help to lower cholesterol levels in the body.
Tocotrienols, on the other hand, are a form of vitamin E.
“We know that vitamin E is very important for the human body – the Recommended Nutrient Intakes for Malaysia has provided specific recommendations on the amount of vitamin E for men, women and children of different age groups,” said Dr Tee.
“Many studies have shown that tocotrienols are a powerful antioxidant and potentially useful for the management and prevention of many chronic diseases,” he added, noting that palm oil is one of the richest natural sources of tocotrienols.
Link with NCDs
Whatever its virtues are though, palm oil is still a fat, and as such, has been associated with the rise in non-communicable diseases (NCDs).
Said Institute of Medical Research medical officer Dr Sophia Rasheeqa Ismail, who spoke on her team’s Systematic Review on Palm Oil and Its Implications on Diet-Related NCDs: “As Dr Tee mentioned earlier, palm oil is one of the major sources of fat in Malaysia. It is also one of the major sources of fat in Asia.
“Because of this and the rising consumption rates of palm oil in developing countries, there are many reports that associate the increasing prevalence of NCDs with the rise in consumption of palm oil.
“Palm oil has been reported to cause an increase in cholesterol levels, to induce arteriosclerosis, and also, to increase CVD (cardiovascular disease) prevalence.”
As such, she and her colleagues decided to review the research on palm oil’s effects on atherosclerosis; cholesterol; the two main types of CVD, coronary heart disease and stroke; type 2 diabetes mellitus; obesity; and cancer.
She noted that despite the controversies surrounding palm oil, there were surprisingly few research papers on its relationship with NCDs; only 65 studies fitted their criteria, with the most – 22 – relating to cholesterol and only one to stroke.
“We wanted to establish a reliable overall effect (of palm oil on NCDs), but we found that there were a lot of limitations in terms of the current evidence.
“Most of the outcomes we wanted to look out for were insufficient, for example, there were no studies that included HbA1C for diabetes or lipoprotein A for CVDs (the most accurate markers for those conditions),” she said.
In conclusion, Dr Sophia said: “The present review could not establish strong evidence for or against palm oil consumption with diet-related NCDs.
“NCDs, being NCDs, are multi-factorial, therefore, a healthier overall diet and lifestyle, as mentioned by Dr Tee, should still be prioritised for good cardiometabolic health.”
Dr Tee had earlier said: “Palm oil has been blamed for many of the ills we see in this country, but in my opinion, there is no one single food item that we can blame – if it were so simple, we would have solved the problem long ago.
“We have to bear in mind that it is total calorie intake that is important, and physical activity as well.”
He noted that palm oil is an energy-dense nutrient, and hence, excessive consumption should be avoided.