A total of 18 IDIs were conducted with consumers with a median age of 34.5 years old (interquartile range: 31, 50 years old). The majority of the participants were female (72.2%) had a tertiary education level (88.9%) and had no comorbidity (77.8%). Some of the participants worked in the private sector (44.4%) and public sector (27.8%), while a few were self-employed (11.1%), retirees (11.1%) and housemaker (5.6%) (Table 1). The interviews lasted between 30 and 80 min.
A substantive theoretical model was developed to explain the considerations of consumers and the process undertaken prior to purchasing online health supplements and natural products. Consumers’ decisions when purchasing these products are the result of a series of assessments regarding the perceived benefits and risks of this activity, and these perceptions are constantly influenced by their experience in the activity and the information they have been exposed to (Fig. 1). When consumers perceive a product-related or process-related risk, they select products, online sellers, sales platforms and/or purchase mechanisms with lower perceived risk. As a result, consumers’ assessments and considerations of the benefits and risks are ultimately integrated into their confidence in five purchase-related elements: (1) product effectiveness, (2) product safety, (3) purchase convenience, (4) fair purchase and (5) online security. The first two elements relate to the product, and the latter three relate to the process.
Conceptually, consumer confidence based on these five elements and the associated risk perceived by the consumer are two sides of the same coin. When consumers perceive a significant risk that potentially negatively affects any of the five element(s) and cannot identify a better alternative with a lower risk, they may have insufficient confidence in the respective element(s), and their perceived risk is likely to be above their acceptable level. In conditions such as this, consumers are unlikely to carry out the online purchase of health supplements and natural products. In contrast, if consumers believe that a perceived risk is adequately overcome or mitigated by methods such as selecting a specific brand or purchasing from a specific online seller or platform, their confidence in those related element(s) increases, and the perceived risk is reduced to an acceptable risk level. Ultimately, consumers may take an acceptable level of risk to purchase a health supplement or natural product online.
Confidence in the five elements of online health supplement and natural product purchasing
From the perspective of the consumer, perceived benefit refers to the ‘perception of relative advantages obtained from an acquisition when purchasing a product or service’; meanwhile, perceived risk is a ‘perceptual sense that any action consumers take will produce consequences they cannot anticipate’ . For the purpose of this study, perceived benefit includes the advantages consumers expect to obtain from the activity of purchasing health supplements and natural products online, whereas perceived risk refers to a negative outcome or issue that consumers are concerned about or believe may occur as a result of purchasing health supplements and natural products online. Consumers consider the benefits and risks when they are in the process of reviewing the various options available in both the product-related and process-related domains before making a purchase. The product domain encompasses all aspects of the health supplements and natural products themselves, including the expected effects or side effects of these products. Conversely, the process domain comprises all the components related to the procedures involved during the online purchase, including product selection and payment through the online sales platform, product delivery to the consumer’s location, as well as customer services from the online seller.
As a result of considering both the perceived benefits and perceived risks, consumers develop a certain level of confidence in both the product-related and process-related domains. Confidence is the feeling of the consumer that they can trust, believe in, and be certain of the good qualities of something , which, in the context of this study, is the product and the process. For any risk identified or perceived in relation to the online purchase of supplements, consumers make an effort to reduce that risk or overcome it. This behaviour is demonstrated when a consumer expresses a preference for a specific seller, company, or online platform. For instance, when consumers perceive that there is a higher risk of receiving fake products from individual sellers, they may opt to purchase from an ‘authentic seller’ (as claimed by the general online sales platform), as these sellers are perceived to have a lower risk of selling fake products. To ultimately engage in the activity of purchasing health supplements and natural products online, consumers must have sufficient confidence in the five elements relating to both the product and process domains: product effectiveness, product safety, process convenience, fair purchase and online security (Fig. 2). The level of confidence in each element varies with each consumer’s experience with the product and process, as well as the information they have gathered over time. Furthermore, the expectations for the five elements vary depending on consumers’ perceptions and the value they place on each element.
Confidence in product effectiveness and product safety
To purchase a health supplement or natural product online, consumers must have sufficient confidence in the product’s effectiveness and believe that the product can help prevent disease, maintain health, or improve their health condition. The consumer must also believe that a product is safe in order to purchase it. Consumers’ emphasis on product effectiveness and safety is evident based on their concerns about product authenticity, which are related to the risks of experiencing ineffectiveness or unwanted side effects from counterfeit products or failing to gain the expected health benefits from it. Overall, consumers tend to purchase authentic products as they have greater confidence in their effectiveness and safety.
Although consumers cannot easily confirm the authenticity of an online product, they develop their confidence in the product’s authenticity through a variety of means, including opting for a product from an established brand, selecting an online product that they have previously seen in a physical pharmacy shop, or making an online purchase from a reliable company or seller. Consumers consider a product from a well-known brand to be safe because no negative events have been reported since its development. From the consumers’ perspective, if their product is unsafe, the company has ‘probably killed millions of people already’ (P13, 40-year-old healthy male). Similarly, consumers also have confidence in the effectiveness and safety of an online product when that specific product is also available in a physical pharmacy, as one may ‘consider that he/she can trust everything that enters the pharmacy (physical pharmacy shop)’ (P06, 30-year-old healthy female). The consumers’ confidence in the established brand or the physical pharmacy shop is transferred to their perceptions of the quality of the respective online product.
Furthermore, consumers prefer to buy from online sellers that are perceived to be credible, as they have greater confidence in the effectiveness and safety of the products sold by those sellers. Online sellers are perceived to be more credible when they record more transactions and receive positive reviews from the customer in terms of their services and product quality. Furthermore, the label ‘authentic sellers’ given by online sales platforms is perceived as an indicator of a seller’s credibility by consumers, which, in turn, increases the consumers’ confidence in the products’ effectiveness and safety. One consumer in our study justified his action of purchasing health supplements from an ‘authentic seller’ by stating the following:
‘…I need to make sure that, you know, the product that I’m buying or purchasing…is an authentic product. So, [the seller’s] reliability [has] a very high… value in my decision-making process.’
(P13, 40-year-old healthy male)
Additionally, consumers prefer to purchase products from the official website in order to reduce the risk of receiving a fake or adulterated product over the Internet. The term ‘official website’ refers to the online website that is owned by the product company and represents that specific company on the Internet. When a consumer lacks trust in an individual seller on a general online sales platform, they may opt to buy health supplements or natural products from the official website of the product company, which they trust to a greater extent. As a result of purchasing from the official website, the consumers’ perceived risk of receiving a counterfeit or adulterated product is reduced, while their confidence in the product’s effectiveness and safety is increased. Similarly, consumers’ preference for purchasing health supplements and natural products from an official website is also an attempt to reduce the process-related risk (e.g., online payment fraud) and to increase their confidence in the respective process-related element of fair purchase. The following examples explain why consumers prefer to purchase from the official website rather than individual sellers:
‘[I] will not [purchase supplements from the general online sales platform], because it is too risky for me, too many fake products. (Laughing) It is acceptable if the product is for external use, but if the product is for oral consumption, I feel that it is too risky.’
(P16, 32-year-old healthy female)
Generally, the perception that a product has been registered with the authorities increases consumers’ confidence in the product quality and, particularly, the product safety. Consumers expect the local authorities to ensure their safety and, thus, believe that all registered products ‘have been checked by the Ministry of Health’ (P03, 34-year-old healthy female). One consumer in our study expressed his preference for ensuring a product is registered with the health ministry prior to online purchase:
‘…if I want to buy a supplement, I will look for [product registration with the authority]. That is one of my priorities.’
(P10, 35-year-old healthy male)
It is worth noting that consumers’ confidence in a registered product is also based on their trust in the authority’s expertise. If consumers do not trust the authority’s capability to evaluate the product safety, the registration status of the product may not influence consumers’ confidence, as they may think that ‘probably the government also does not know how to certify them’ (P09, 50-year-old healthy female). Furthermore, consumers’ trust in the local government’s policy for controlling online supplement sales influences their confidence in the effectiveness and safety of health supplements and natural products. Specifically, consumers have lower confidence in product safety when they perceive a lack of monitoring and regulation of online supplement sales by the authority, as ‘nobody verifies what they, [the online sellers], are selling’ (P02, 29-year-old healthy female).
Confidence in process convenience, fair purchase and online security
Firstly, to perform an online purchase, consumers must have confidence in the process’ convenience, meaning the process of product search, selection, order and transaction must be perceived to be feasible and manageable. Managing an online purchase, whether on a company website or a general online sales platform, is simpler for younger compared with older consumers. However, older consumers seek help from those they trust to assist them in making the online purchase, such as by ‘making a number of purchases initially under someone’s supervision’ (P18, 79-year-old female with NCDs). This use of assistance in making purchases could increase the consumer’s confidence in the element of process convenience.
Notably, process convenience encompasses not only the ease of obtaining a product but also the ease of gathering personalised information that aids in the product search. The importance of being able to gather this information explains why some consumers prefer online purchases of health supplement and natural products, as these purchases allow for ‘easy and faster access to information’ (P11, 24-year-old healthy female). Indeed, this information can be obtained from an Internet search engine or a product review shared by a peer customer rather than by physically visiting different shops for comparison. However, other consumers prefer physical shop purchases in order to obtain product information directly from a shop employee; specifically, these consumers believe this process is more personalised and saves time as one ‘doesn’t need to do their homework (surveying about a product)’ (P02, 29-year-old healthy female).
Secondly, a fair purchase is an important element that consumers consider prior to making an online supplement purchase, as they must feel that they have adequate freedom to make an unbiased decision in their choice of supplement when making a product purchase. Perceived conflicts of interest between the seller and the consumer often cause consumers to question whether the recommended product is appropriate for them, as they perceive that physical shop personnel ‘tend to push them towards supplements that they will get profit from’ (P11, 24-year-old healthy female). Additionally, consumers are more confident in the fairness of a purchase when they understand how to file a product complaint or leave a negative review for an online seller if an unsatisfactory incident occurs. Similarly, some consumers prefer to purchase from the product company’s official website due to this giving them greater confidence in the fairness of the purchase. Indeed, purchasing from the official website means a specific company can be held accountable when a negative incident occurs, such as unsatisfactory product experiences or online payment failure:
‘… if you are directly dealing with the company (purchase through the official website)… You have the receipt to prove that you bought it from them. If anything happens, touch wood, you can still deal with the company; this is a protection for yourself.’
(P16, 32-year-old healthy female)
Thirdly, online security emerged as another process-related factor that consumers considered prior to purchasing online health supplements and natural products. Particularly, consumers expressed their concerns about data theft and financial loss due to disclosing personal and financial information during the process of online purchasing. One of our consumers expressed her preference to purchase health supplements and natural products from individual e-commerce platforms, particularly those belonging to an ‘internationally established company’, because ‘the risk of personal information being hacked is lower’ (P08, 31-year-old healthy female) compared to shared e-commerce platforms. Another consumer expressed great confidence in online security based on his understanding of the security measures in place for online payment mechanisms. This consumer explained:
‘As long as you saw some big player in the market when you check out that time, for example, Razorpay, iPay88 [and] senangPay… all [these are] actually governed by a Paynet, which is a subsidiary of BNM (Bank Negara Malaysia, the Central Bank of Malaysia). So, I don’t think there’s a risk…’ (P14, 31-year-old healthy male)
Taking an acceptable level of risk in online purchases of health supplements and natural products—the core category
By definition, a person is said to be taking a risk when they do something that may result in loss or failure  in order to achieve something . In the context of this study, the goal of the behaviour is to obtain health supplements or natural products, and the loss or failure that the consumer may experience refers to the negative consequences that may occur when obtaining these products online. The anticipation of these consequences constitutes the above-mentioned ‘risk’ that consumers perceive, which can be product- or process-related. It is worth noting that not all risk must be eliminated for consumers to purchase health supplements and natural products online. In particular, when a consumer is willing to accept a certain level of risk associated with this activity, this indicates risk-taking behaviour among consumers who buy health supplements and natural products online. For example, despite conducting extensive research and consideration prior to purchasing an online supplement, one consumer in our study still considered himself ‘pretty lucky’ because he didn’t have ‘any bad experience purchasing online’ thus far (P13, 40-year-old healthy male).
Taking some level of risk is deemed necessary for consumers to achieve the intended goal of enjoying the potential benefit of a supplement, because if the consumer is ‘suspicious or not willing to believe all the time, [they may] end up not buying [any supplements]…’ (P18, 79-year-old female with NCDs). Therefore, consumers are willing to take a certain level of risk in exchange for the potential benefit they expect from the online purchase of health supplements and natural products. For instance, one consumer in our study took the risk of purchasing and taking an online supplement for the potential health benefits of the product despite the health risk she perceived from taking a supplement, which she considered ‘unnatural’ compared with eating fruits and vegetables. In this scenario, she took the risk of her health being harmed by a potentially unsafe product.
‘I… I… really do not know the effects [of the supplements]. But I tell myself, take it (the supplements) for the peace of mind… I also tell myself these are not natural things.’ (P18, 79-year-old female with NCDs)
Another example identified in our study involved a risk related to the process. Specifically, one consumer decided to make an online purchase despite being aware of the risk of reduced supplement quality due to improper delivery conditions. This is fairly common in the present world, where ‘time [constraint] is always [a] problem.’ (P18, 79-year-old female with NCDs).
Consumers often perceive a greater risk during their initial attempt at purchasing health supplements or natural products online, when they encounter more uncertainties about new products, as well as when using a new online platform that they have no experience with. At these times, consumers put more effort into checking other consumers’ reviews, the seller’s credibility and the product quality to build confidence in the aforementioned five elements related to the purchase decision. The initial attempts at online supplement purchase represent a greater level of risk-taking behaviour by consumers, as they ‘have to go for it, [as] only then can [they] prove [whether the online purchase is] feasible or not’ (P18, 79-year-old female with NCDs).
Furthermore, following the initial purchase attempts, ‘risk-taking’ behaviour persists for regular purchases. Although consumers require adequate confidence in the aforementioned five elements of the purchase decision, this does not mean that they do not perceive any risk in their subsequent online supplement purchases. Instead, in subsequent purchases, their perceived risk is mitigated to a lower level that they are comfortable with. For instance, one consumer in this study agreed that it was still possible for her to obtain fake products even though she had opted to purchase from an authentic online seller. However, she took the risk and made the online purchase after sufficient deliberation regarding the online seller from whom she intended to purchase the health supplement:
‘…I’ve tried to filter, to buy it from an authentic seller, [or] an authentic shop, right? … So, I’ve tried to eliminate the risk of er… buying from an individual seller.’
(P03, 34-year-old healthy female)
The acceptable level of risk refers to how much risk consumers can tolerate when deciding to purchase supplements online. This level is personal and is largely determined by the consumer’s perception of control over the potential consequences resulting from the risk. Having control over the consequences involves the consumer having the confidence to manage or handle the consequences or the impact of the consequences being acceptable for them. When consumers perceive they have this control, they perceive a lower risk in performing the activity and, thus, are more likely to purchase supplements online. For example, one consumer used ‘trial and error’ with health supplements purchased online in order to evaluate their effects. The term ‘trial and error’ demonstrates the consumer’s awareness of the possibility of ‘encountering errors’ in her trial, meaning the consumer perceived the risk of product ineffectiveness to be manageable.
‘I [use] trial and error. For example, after taking [the supplement] for a while, I would stop and see, and then… [I will] resume taking [the supplement and] will feel the difference; this is how I test it’
(P12, 45-year-old healthy female)
Furthermore, if consumers can mitigate the perceived risk to an acceptable level with perceived manageable consequences (e.g., purchasing an authentic product, using an authorised online sales platform to avoid receiving a fake product, or buying a smaller quantity to avoid financial loss), they are more likely to purchase supplements online.
On the contrary, when consumers lack confidence in dealing with the resulting consequences, or when the impact of the resulting consequences is perceived to be too detrimental (e.g., loss of privacy, harm to health due to serious adverse effects), consumers perceive a lack of control over the potential consequences. As a result, the perceived risk exceeds their acceptable level, thus reducing their willingness to purchase supplements online. In our study, one consumer explained that she would not risk purchasing and taking a health supplement if it caused palpitation, as this is a side effect that involves an important organ and that she perceives to be possibly fatal. The perceived risk was beyond her acceptable risk level, and, thus, she was unwilling to purchase and consume the online health supplements.
‘… if we have general knowledge, we feel that it is abnormal for the heart to palpitate. If you experienced this (palpitation) every time you take the supplement, would you dare to take it?’
(P15, 50-year-old female with an NCD)
Similarly, issues concerning the disclosure of personal information, including one’s home address, are associated with the risk of compromised personal safety, which could lead to detrimental consequences. In this study, one consumer expressed her perceived lack of control regarding the potential worst-case scenario, stating that if she ‘suddenly receive[s] [scam calls from fraudulent groups] … [she] will not be able to react’ (P08, 31-year-old healthy female). Consequently, this consumer decided to refrain from making online purchases, as she found no alternative ways to mitigate the risk:
‘In fact, there is nothing we can do about it (personal information security)… As a result, my strategy is to do less—reduce my purchasing frequency.’ (P08, 31-year-old healthy female)
It is worth noting that, consumers’ willingness to take the risk of purchasing online health supplements or natural products could be influenced by their health conditions. For example, in our study, one participant with a history of liver disease was more cautious in his use of health supplements due to the possible harm from the inappropriate use of these products, as he felt obligated to ‘take care’ of his liver. (P17, 74-year-old male with NCDs). This participant’s willingness to take a risk when buying health supplements online is reduced by his medical history of liver disease. However, another participant claimed to be taking a health supplement because ‘it is supposed to be good for her macular degeneration’ (P18, 79-year-old female with NCDs). This participant’s health condition most likely reinforces her willingness to take the risk despite her perception that health supplements, which are ‘made from chemicals’, may be ‘not good’ for her health (P18, 79-year-old female with NCDs).
Generally, ‘risk-taking’ behaviour is not limited to the purchase of health supplements and natural products on the Internet but also from physical shops. The following excerpt demonstrates that one consumer in this study perceived that there is a similar level of risk of receiving a fake product from a physical shop compared with online sales platforms:
‘Because if I buy at a [physical] shop, I can’t really differentiate (identify a fake product), right? … [but] we will still buy it, right? It’s the same.’ (P03, 34-year-old healthy female)
Overall, the growing popularity of online shopping encourages online purchasing behaviour because a borderless online marketplace with a greater variety of supplements is available to the general public. Furthermore, the components of risk that consumers need to manage when purchasing health supplements or natural products online may differ from those related to purchasing these products from physical shops.