Tropical oils consumption and health: a scoping review to inform the development of guidelines in tropical regions

Background Tropical oils such as palm and coconut oils are renowned for their high saturated fat content and culinary versatility. However, their consumption has sparked debate regarding their health benefits and production concerns. The purpose of this review was to map existing evidence on the health benefits and challenges associated with the consumption of tropical oils. Method The recommendations for conducting a scoping review by Arksey and O’Malley were followed. PubMed, Dimensions AI, Central, JSTOR Google, Google Scholar, and ProQuest databases were searched for relevant papers. The predetermined keywords used were Consumption” AND “Tropical oil,” as well as “Health benefits” OR “Health challenges” AND “Tropical Countries.” Peer-reviewed and grey literature published in English were eligible for this review. Result Tropical oils, such as palm and coconut oils, provide health benefits including essential vitamins (A and E) that enhance ocular health, boost immunity, and support growth. They are also recognised for their role in managing high blood sugar, obesity, and cholesterol levels, while offering antioxidant and anti-inflammatory properties. These oils have wound-healing abilities and are commonly used in infant nutrition and traditional cooking. Nevertheless, prolonged and repeated use of tropical oils to high temperature can degrade vitamin E, whereas excessive intake may result in overdose. Health concerns include oxidative risks, diabetes, cancer, coronary heart disease, high blood pressure, and acrylamide formation due to production challenges excessive consumption. Additional issues include obesity, suboptimal oil production, misconceptions, regulatory obstacles, and preferences for alternative fats. Conclusion This review suggest that tropical oils provide essential health benefits, including vitamins and antioxidant properties, but pose significant health risks and production challenges, particularly when exposed to high temperatures and through excessive intake. Guidelines on the consumption of tropical oils in the tropical regions are necessary to regulate their consumption. Supplementary Information The online version contains supplementary material available at 10.1186/s12889-024-19949-x.


Ghana
To evaluate the quality and safety of palm oil samples from seven major cities in Ghana using a completely randomized design with three replications Randomized design Ghana Samples of palm oil 70 1.
Risk of hydrolysis and oxidation as a result of consuming unrefined crude palm oil (CPO) 2.
Consumption of palm oil containing Sudan IV dye which contains casinogenic effect 3.
Longer length of time of storing fruits coupled with the use of inappropriate equipment and inadequate processing time compromise the quality of CPO.

1.
Palm contains alpha-and beta carotenes, and lycopene, which account for its characteristic dark red colour

2.
Carotene in palm oil has vitamin A and E to mitigate against vitamin A and E deficiency.
Hasanuzzaman & Nahar, 2022 Malasia Aimed at utilization potentials of oilseeds in the tropics, therapeutic considerations, source of vital nutrients for consumers, prospects, and challenges of oilseed production for increased global competitiveness review Malaysia 1. Lack of modernization, low oil recoveries, lack of standardization of product quality, use of local technologies and Widespread inefficiency affects domestic markets and export quality.

1.
Palm oil reduces high blood sugar and cholesterol level.

2.
It is used as a component of infant milk powders because of its easy digestibility and stable flavor.

3.
Palm oil has natural vitamin E which protects and repairs damaged cells.Suryani et al., 2020 Thailand To study the unique factors of virgin coconut oil (VCO) compared with coconut oil.experimental Malaysia 1.
Virgin Coconut Oil is useful against microbes, bacteria and viruses.

2.
Virgin Coconut Oil useful for helping one lose weight in terms of metabolism.

3.
Virgin Coconut Oil causes people to consume less carbohydrates, which eventually reduces body weight.

4.
Virgin Coconut Oil is used as antioxidants 5.
Virgin Coconut Oil reduces high blood pressure and 6.

Virgin Coconut Oil affects the healing after an ovariectomy Shankar et al 2017 Thailand
To understand the prospects for future health-focused policy development to limit food use of palm oil and promote a greater diversity of oils in Thailand's food system

Interviews
Thailand 18 stakeholders 8 from public sector 7 from private sector 3 from NGO 1. Doubt and misperception about negative health implications as a result of palm oil consumption.

2.
Complex regulatory environment with little space for health-related considerations prevent people from palm oil consumption 1.
Palm oil increases energy availability than any other food group.

2.
Palm oil serves as an ingredient in a large variety of processed food product.

Nigeria
To combine and condense the body of research on the processing, characterization and use of palm oil especially in frying as well as suggest areas that need further research.
There is loss of some vitamin Es during processing and refining of palm oil 2.
Prolong use of Palm oil (vitamin E) inhibits growth.

1.
Palm oil has a unique fatty acid and triacylglycerol profile which makes it suitable for numerous food applications 2.
Palm oil is used to prepare infant formulae and provides vitamins A and E to the body.

3.
The tocopherols and tocotrienols in the palm oil act as anticancer, ant-inflammatory agents and also control atherosclerosis, and decrease cholesterol.

Thailand
To investigate the effect of tropical oil (palm and coconut oils), lard, and other common vegetable oils (soybean and rice bran oils) that are widely used in tropical and Asian countries on lipid profiles.
The crave for the consumption of saturated fat rich oil particularly from animal fats inhibit the use of palm oil.The nutraceuticals and phytonutrients from palm oil reduce cholesterol and diabetic levels in adults 2.
palm oil tocotrienol as an antioxidant serves in prevention and treatment of bone-related illness.

3.
The anti-inflammatory effect of palm oil phenolics may prevent the 2.
Excessive consumption of high amount of saturated fats of palm oil is link to heart disease.formation of neurodegenerative diseases such as Alzheimer's and Parkinson's.

Singapore
To assess the effect of coconut oil consumption on blood lipids and other cardiovascular risk factors compared with other cooking oils using data from clinical trials Review 1.
High Coconut oil consumption results in significantly higher Lopoprotein cholesterol and leads to cardiovascular diseases.

1.
Consumption of coconut fat reduces serum cholesterol levels compared with non-tropical vegetable oils.

2.
In Consumption of coconut oil increase the activities of enzymatic antioxidants such as catalase and superoxide dismutase which are involved in the detoxification of peroxide and superoxide radicals.

3.
Efficiently consumption of coconut oil reduces acute inflammation.
Coconut oil reduces cardiovascular diseases 6.
Coconut oil plays an important role in regulating insulin resistance and associated glucose metabolism.

7.
Fermented VCO has shown to reduce paracetamol-induced toxicity by restoring liver function markers and hepatic morphology 8.
It has been shown that fermented VCO possess activities against a variety of strains including Candida Abdullahi et al 2023

Nigeria
To provide an overview of quality variation and various contaminants in locally processed palm oil Review 1.
Poor handling and transportation lead to adulteration of the palm oil.

2.
The variations in the chemical composition of the palm fruit, environmental factors, variation in processing leads to Microbial contamination.Higher microbial counts and the presence of toxic microorganisms.

1.
Palm oil provides essential nutrients for growth 3.
Frequent consumption of contaminated oil leads to accumulation of metals in body fluids and vital organs.4.
Consumption of unsafe adulterated palm oil cause complicated health conditions that can lead to death.Kappally et al

UAE
This article attempts to scientifically review the therapeutic benefits of this oil.
The myth or perception of coconut oil being a deleterious to health as it would block the arteries and cause heart disease.

1.
Palm oil is helpful in skin care, hair care, stress relief, weight loss and level maintenance, immunomodulatory effects and cardiovascular uses.

2.
Palm oil acts as anti-stress and antioxidant which reduces lipid peroxidation and increase the activity of SOD in the serum of mice undergoing the forced swim test and the brains of mice subjected to chronic cold restraint 3.
Coconut oil as antiinflammatory.

4.
It aids in Wound healing as where the skin or other body tissue repairs itself after injury.

5.
Coconut oil protects the skin from chronic skin diseases.6.
Coconut oil serves as an ocular rewetting agent.7.
Coconut oil prevents blood pressure.

8.
Daily intake of coconut oil causes reduction in body fat accumulation.

Malaysia
This review is aimed to provide a comprehensive overview of the physicochemical properties and extraction processes of red palm oil, its nutritional properties and applications in food.
Palm oil can generate reactive oxygen series that will induce DNA damage 2.
Palm oil is an excellent source of carotenoids for pro-vitamin A.

3.
Palm oil Increases serum retinol and lower cholesterol levels 4.
Palm oil Increases antioxidant level and reduce risk of cancer Nondzor et al, 2015

Ghana
To ascertain consumer's knowledge, perceptions and preference of edible oil(palm oil, coconut oil, sunflower oil, groundnut oil and palm kernel oil)
Unrefined oils are high in cholesterol.

1.
Edible oils have health benefits and nutritional values.

Iran
To review the physicochemical properties, fatty acid profile and nutrition in palm oils.
The composition of fatty acid of palm oil is assumed to be a cause of coronary heart disease.
1, Palm oil contains a high concentration of natural carotenoids 2.
Palm oil prevents cancer 3.
Palm oil has higher oxidative stability and results in high quality and tasty food.This systematic review focused on studies that reported the association between Virgin Coconut Oil and the biochemical measurements associated with cardiovascular diseases.
High amount of consumption leads to overdose of vitamin E 1.
Virgin Coconut Oil controls blood sugar and prevent high blood pressure.

2.
Virgin Coconut Oil is rich in polyunsaturated acids which are beneficial to cardiovascular health.

3.
Consumption of palm oil leads to reduction in obesity.

4.
Virgin Coconut Oil improves the lipid by decreasing the concentrations of total cholesterol, triglycerides and low-density lipoprotein cholesterol Deen et al, 2021

Sri Lanka
This review discusses the composition and functional properties of coconut oils extracted using various processing methods.
Lack of supportive scientific evidence deters people from coconut oil consumption.

1.
Coconut oil has hypocholesterolemia, anticancer, antihepatosteatotic, antidiabetic, antioxidant, anti-inflammatory, antimicrobial and skin moisturizing properties Santos et al., 2019 Brazil To determine coconut oil intake and its effects on the cardiometabolic profile Review 1.
Coconut oil has the following health benefits such as cardiovascular disease (CVD), weight loss, Alzheimer's disease, bone loss, diabetes, dental caries and prevention of atopic dermatitis and hair damage.Joshi et al., 2020 India To evaluate the antiviral, antibacterial and antifungal benefits of coconut oil.
Coconut oil act as antioxidant and natural antibiotic and also help modulate immunity 2.
Coconut oil helps in cholesterol lowering, reduction of cardiovascular disease risk, weight loss, appetite curb, 3.
Coconut oil improves cognitive functions and strengthening of immune system.Ntsefong et al., 2016 To review overview of controversies surrounding the oil palm production and consumption.
High fat intake increases the risk of heart disease.

1.
Palm oil is the main traditional cooking oil Cameroon 2.
Palm oil causes cancer due to formation of acrylamide at high frying temperatures Boateng et al., 2016 Ghana The aim of this paper is thus to contest the negative publicity that coconut and palm oils have suffered, via exploring their unique potential roles in the nutritional and health status of the less endowed peoples of the world, (particularly those from the West African Subregion), and in improving food security to enhance national development Review 1.
Excessive intake of palm and coconut is strongly associated with an increased prevalence of obesity and an increased risk of developing coronary artery disease, high blood pressure, diabetes mellitus, and certain types of cancer.

1.
Palm and coconut oils serves as a carrier of preformed fat-soluble vitamins, enhancing the bioavailability of fat-soluble micronutrients and providing essential substrate for the synthesis of metabolically active compounds 2.
Palm and coconut oil have been used as a primary source of dietary fat as well as a remedy for illnesses 3.
Palm oil contains carotenes which are precursors of vitamin A, which prevents night blindness, aids in maintenance of tissues and promotes growth.

4.
Palm oil is rich in vitamin E, which is composed mainly of tocopherols and tocotrienols.Which acts as antioxidants reducing plasma cholesterol.Vogel, et al., 2020 Brazil To evaluate the influence of coconut oil on body composition, lipid profile 36 and glycemia in men with obesity

Randomized control clinical trial
Men with obesity 29 1.
Coconut and soyabeans oil consumption reduces obesity 2.
Coconut has effect on management of diabetes.

India
To systematically summarized all highquality evidence on the usage of coconut oil for health-related benefits.
Coconut oil helps in the prevention and treatment of atopic dermatitis and oil pulling for the prevention of dental caries.
Coconut oil reduce the risk of cardiovascular diseases 4.
Coconut oil aids in weight loss and improvement of cognitive functions, 5.
Coconut oil consumption reduces risk of diabetes, and also enhance the immune system, and promoting wound healing India To find out the efficacy of coconut oil application for skin maturity, prevention of sepsis, hypothermia and apnea, its effect on long-term neurodevelopment and adverse effect of it.
Use of coconut oil helps in dermal maturity and better neurodevelopmental outcome.

2.
Smearing coconut oil on the new-borns reduces water loss and hypothermia thereby reducing infections and newborn mortality 3.
Coconut oil is also helpful in promoting growth Chew, 2018

Malaysia
To determine the benefit of coconut oil in management of atopic dermatitis review 1.
Virgin Coconut oil is useful in the management of Atopic Dermatitis 2.
Coconut oil is use as antioxidant and anti-inflammatory 3.
Coconut oil is useful in healing of wounds on the impact of Palm oil on health, social and economic aspects, environment, and biodiversity in the Malaysian context, and discuss mitigation strategies based on the sustainable development goals(SDGs)