1. Introduction
Contemporary societal concerns surrounding the relationship between food and health have led agri-food businesses to become keenly interested in studying and increasing the health benefits of their products. This trend extends to wine, an agricultural product that has numerous beneficial health effects due to its myriad components (Ortuño, 2009). Moderate wine drinking with meals is, for example, one of the main characteristics of the Mediterranean diet (Arós & Estruch, 2013). In combination with foods typical of the Mediterranean diet such as olive oil, vegetables and white meat, consumption of a moderate amount of red wine offers even greater benefits in terms of reducing cardiovascular risk (Mezzano et al., 2001).
The so-called “French paradox” provides another example of the beneficial effects that wine may have on health. It was observed that a diet high in fats, which is typical of the French, did not correlate to the percentage of cardiovascular events that occurred, which was lower in France than in other countries where fatty foods were frequently consumed. It was posited that moderate consumption of wine over an extended period might explain this phenomenon (Renaud & de Lorgeril, 1992). What is known for certain is that as a result of this study, wine consumption rose in the USA and scientists began to further investigate the effects of diet and wine. It seems likely that myriad indeterminate variables may be triggered by the link between alcohol and polyphenols, as alcohol could increase the body’s absorption of other components in wine (Brust, 2010).
In summary, as described by Leighton and Urquiaga (2007), wine and the Mediterranean diet can be said to have synergistic protective effects on cardiovascular risk factors, and some of the protective changes observed in connection with moderate wine consumption only materialize in diets high in fat.
In addition, people generally have a positive view of the beneficial effects of moderate wine consumption (Ortuño, 2009) although consumers lack sufficient, scientifically-supported information to enable them to make safer decisions regarding the consumption of alcoholic drinks (Henley et al., 2011). In fact, consumers find it difficult to comprehend nutritional information and to distinguish between the different levels of scientific evidence behind food claims (Higgins & Llanos, 2015). Against this backdrop, primary care physicians have an important role to play in balancing public health with the benefits of moderate consumption of wine. Given its role in improving the health of a country’s population, primary care is a cornerstone of any health system (Arrazola-Vacas et al., 2015).
This paper aims to shed light on the perceptions of Spanish primary care physicians regarding moderate consumption of wine. By providing information on the attitudes of medical workers in particular, it adds significant value to current research knowledge. The United States, for example, considers moderate alcohol consumption by adults of legal drinking age to be a daily amount of 10 g ethanol (1 drink) for women and 20 g ethanol (2 drinks) for men (Hrelia et al., 2022). This paper also analyses the views of primary care physicians in order to consider this assessment with regard to the specific case of wine. The vast majority of chronic illnesses are largely preventable with hygiene and dietary measures (Arós & Estruch, 2013).
1.1. Literature Review: Wine and Health
Multiple publications describe wine’s possible health benefits (Biasi et al., 2014). As detailed in Table 1, a brief literature review reveals numerous positive effects on health stemming from moderate consumption of wine. Chief among these is its cardioprotective effect, which is owing to multiple factors. On one hand, it is believed that ethanol can increase levels of high-density lipoprotein (HDL, or “good cholesterol”) and apolipoproteins A-I and A-II, in addition to reducing platelet aggregation, which in turn triggers changes in blood coagulation and fibrinolysis. On the other hand, phenolic compounds are known to be excellent lipid antioxidants which act by inhibiting the oxidation of low-density lipoprotein (LDL, or “bad cholesterol”) and increasing the synthesis of nitric oxide, which improves arterial vasodilation and reduces monocyte adhesion to the endothelial wall, thereby preventing atherosclerotic plaque formation.
Moderate wine consumption also protects against Type 2 diabetes mellitus by reducing insulin resistance and improving insulin secretion and sensitivity. It can also improve blood sugar levels through a range of mechanisms such as the inhibition of glucose absorption in the intestine or peripheral tissues (Rodrigo et al., 2011).
Another significant protective effect attributed to wine is its impact on neurodegenerative disorders such as Alzheimer’s and Parkinson’s. Multiple studies have shown that wine, more specifically, resveratrol, has a preventive effect against Alzheimer’s disease, improving cognitive function and reducing memory loss. Alzheimer’s patients develop brain lesions due to the accumulation of a monomer called amyloid beta. Several studies have concluded that resveratrol helps to break down these peptides, thereby protecting the brain.
The development of various forms of cancer, a multifactorial disease, has been linked to diet. In combination with the Mediterranean diet, wine has a beneficial and synergistic effect that protects against some types of tumours (Sancho & Mach, 2015). In recent years, several studies have highlighted the protective and preventive effect that polyphenols may have on carcinogenesis (García Rodríguez et al., 2015), demonstrating their ability to inhibit the growth of tumours in animals and cell cultures.
Numerous recent studies have also suggested that diet may have an effect on age-related vision loss (Fernández-Araque et al., 2017). Drinking wine brings the positive effects of antioxidant compounds, specifically polyphenols, into play in ocular processes. These compounds have been reported to have direct and indirect beneficial effects on the progression of glaucoma (Giaquinta Aranda et al., 2017).
Intestinal diseases have also been studied in relation to wine consumption. Polyphenols reach higher concentrations in the intestinal mucosa than in other tissues, which increases their intracellular antioxidant effect. Most phenolics in wine target the redox-sensitive transcription factor NF-κB, which controls the inflammatory cell signalling cascades that have been implicated in the development of colorectal cancer and the pathogenesis of IBD (Biasi et al., 2014).
Other benefits associated with wine consumption include the regulation of haemostasis and blood pressure and the reduction of LDL cholesterol. Given the numerous effects that wine can have on health, the first research question of this study is “What benefits for human health are associated with drinking different types of wine, in the opinion of primary care physicians?”.
As described above, extensive scientific evidence supports the possible existence of health benefits from moderate wine consumption. The most recent studies confirm the valuable role of moderate wine consumption, especially red wine, in the prevention and treatment of chronic diseases such as cardiovascular disease, metabolic syndrome, cognitive decline, depression, and cancer (Pavlidou et al., 2018). Furthermore, the majority of the reviewed articles indicate that moderate consumption of red wine reduces the risk of developing various diseases, consistent with the findings presented in the literature review by Serio et al. (2023).
It is also, however, important to consider consumers’ attitudes toward drinking wine, as a predisposition to view a product or idea in a certain way influences the actions that are taken. Consumers have trouble distinguishing between the different levels of scientific evidence that support food claims, and this may arouse a degree of scepticism when choosing products such as wine (Higgins & Llanos, 2015). Their perceptions and knowledge will divide them into different groups, playing a key role in whether they purchase a particular drink. In marketing, it is often said that what a consumer doesn’t perceive, doesn’t exist and has no value for them. If consumers view a certain product as healthy, for example, that favourable view will likely cause them to consume it more often, or even to start consuming it for the first time. Attitudes that are formed may even be rooted in incorrect beliefs or associations. Despite all of the knowledge and information available about the potential benefits of moderate wine consumption, if a person views wine as being negatively associated with health, that attitude may cause them to stop consuming it despite the irrationality of this decision.
Authors such as Yoo et al. (2013) and Higgins and Llanos (2015) have employed a scale to measure attitudes towards the relationship between wine consumption and human health. Yoo et al. (2013) assessed attitudes to wine in relation to health and observed that Koreans were more likely than Australians to choose wine based on health criteria. Similarly, Higgins and Llanos (2015) reported that consumers’ sociodemographic characteristics had a bearing on whether health benefits were perceived. For example, women were more likely than men to be influenced by the awards a wine might have won or by the opinions of restaurant staff. The respondents in their study had a favourable view of wine, considering it healthier than other alcoholic drinks. However, the study identified various groups of consumers who displayed a greater interest in the health benefits of drinking wine. Both of these studies focused on consumer attitudes, giving no consideration to the views of some of the key players in matters of health: medical workers. Primary care physicians are an important source of information and have been identified by Varela Veiga et al. (2003) as the most suitable health workers to manage alcohol consumption. In view of this, the second research question of this study is “What attitude do primary care physicians have toward alcoholic drinks, in particular wine?”. It also aims to determine whether their attitudes differ, as do those of consumers.
2. Materials and methods
The information used in the study was collected via a personal survey of primary care physicians in Spain which is detailed in Table 2. The total number of these professionals is 37,593 (Ministerio de Sanidad, 2024). Stratified random sampling with proportional allocation by region was used, with the number of respondents distributed according to the number of physicians in each region. Different regions of Spain were considered because wine production is more important in some than in others, resulting in a greater wine culture in those where the industry has a stronger presence. Fieldwork was conducted at a national conference. This choice was made because physicians acknowledge the need to continuously seek information, with attendance at such events serving as a key method for updating their knowledge (Galli et al., 2015). The validity of the survey was assessed based on content, while reliability was evaluated using Cronbach’s alpha, obtaining a score of 0.72, which is deemed acceptable (Hair et al., 2006). Finally, it should be noted that the maximum margin of error is ±7% in the worst possible case (p=q=0.5).
The questionnaire asked the physicians how much wine consumption per day they would consider to be moderate. In keeping with the study’s conceptual framework, the questionnaire also listed the main health benefits of drinking wine and asked respondents whether they were associated with red wine, white wine, no wine consumption at all, or whether they didn’t know or were unable to answer. The “no wine” option was included because the alcohol content of wine could cause it to be negatively associated with health, leading to the perception that it lacks any health benefits at all. Another question, based on the scale proposed by Yoo et al. (2013) and Higgins and Llanos (2015), measured attitudes towards the relationship between wine consumption and health. For this purpose, a 5-point Likert scale of agreement or disagreement was used. Finally, information about the primary care physicians surveyed was collected for classification purposes.
Quantitative data processing was performed via simple correspondence factor analysis and cluster analysis. Correspondence analysis is a descriptive technique used to represent contingency tables, i.e., tables that display the frequency with which two or more qualitative variables appear in a set of elements. Cluster analysis, for its part, uses a set of variables for each subject to measure the similarity between them by estimating distances. The program CAR (Lorenzo-Seva et al., 2009) was used to perform the simple correspondence factor analysis, while SPSS was used for the cluster analysis.
3. Results
As regards the characteristics of the study sample (see Table 3), 63.3% were women, the average age of the doctors surveyed was 49.4 years, and they had worked as primary care physicians for an average of over 20 years. 51.8% of those surveyed said they personally consumed wine at least once per week and almost two out of three of the doctors quantified moderate wine consumption as between half a glass and one glass of wine per day.
The health benefits perceived by the primary care physicians in association with each type of wine are analysed below. Table 4 shows their responses regarding the potential benefits of moderate consumption of red wine, white wine, and no wine, as well as the number of respondents who answered “Don’t know” or “No answer”. Given the extensive size of this table and to maximize comprehension, the discussion focuses on the correspondence analysis detailed in Tables 5 and 6.
Table 5 shows that the first axis explains almost 91% of the variance between the two data sets analysed. Adequate interpretation is thus possible as this is well above the variance of 50-60% recommended for social sciences (Hair et al., 2006).
Table 6 shows the coordinates and the inertia explained by the response given (red wine, white wine, no wine or unsure/no answer) and the possible health benefits analysed for Axis 1. Red wine makes the largest contribution to the first axis, explaining 64.4% of the inertia. The “no wine” option is also well represented, at over 20%. With respect to potential health benefits, the following variables are well represented on this axis, making a significant contribution to its formation: “Helps the cardiovascular system” (58.8% of inertia) and “Helps regulate blood sugar levels” (10.9%). Consideration of the coordinates of the responses and the different health benefits indicates that primary care physicians associate red wine with aiding the cardiovascular system but don’t perceive or associate the consumption of any type of wine with improved blood sugar regulation.
Two different aspects can be distinguished in the physicians’ attitudes towards moderate wine consumption and its relationship to health. On one hand, as Table 7 shows, they believe it can lower the risk of certain diseases and that wine is a healthy drink or has more and better health-promoting properties than other alcoholic drinks. In other words, they take a positive view. However, they also take a critical view of patients’ knowledge of how much wine it is healthy to consume and of its potentially harmful health effects, or they indicate that the amount of wine consumed must be limited, with the last variable receiving the highest score (4.3). However, in certain cases the coefficients of variation indicate a wide dispersion that may reflect the existence of primary care physicians with differing opinions. A cluster analysis was thus performed, using the variables detailed in Table 7. After reviewing the resulting dendrogram, it was determined that the best solution was that of three groups of physicians.
Table 8 details the values by group for each of the variables used to assess the attitudes of primary care physicians towards the relationship between wine consumption and health. Three groups with different characteristics were identified.
Group 1 encompasses 20.1% of all physicians surveyed and displays a favourable attitude toward the relationship between wine and its health-promoting properties. For example, this group agrees quite strongly with the statement “Wine has more or better health-promoting properties than other alcoholic drinks” (4.1). It also views patients as responsible. For example, it gives a score of 3.7, the highest of the three groups, to the statement “Patients know what moderate wine drinking is”. This group could thus be labelled “Favourable” primary care physicians.
Group 2, the smallest of the three, represents slightly more than 14% of the doctors surveyed and disagrees that wine consumption is healthy. It gives the lowest rating, 1.5, to the statement “Wine is a healthy alcoholic drink”. It also distrusts patients’ awareness, disagreeing with the statements “Patients display knowledge of how much wine it is healthy to drink” (1.2) and “Patients know what moderate wine drinking is” (1.6). This group could thus be labelled “Unfavourable”.
Finally, Group 3, which is the most numerous and includes nearly two-thirds of the physicians surveyed (65.8%), perceives wine as healthy, as does Group 1. Like Group 2, however, it views patients as irresponsible with respect to how much wine can be consumed, an opinion made clear in its score of 1.7 for the statement that “Patients know what moderate wine drinking is”. This group could be labelled “Ambivalent”, as it views moderate wine consumption as favourable for health but distrusts patients.
Finally, Table 9 profiles the segments identified based on their views regarding wine consumption and their own personal characteristics.
Group 1, labelled “Favourable”, quantifies moderate wine consumption in the highest amount (1-2 glasses or more than 2 glasses per day), and 7 out of 10 of the physicians in the group drink wine at least once a week. This reaffirms the label of “Favourable” assigned to this group, which is the only one to contain more men (53.7%) than women. Finally, with respect to years worked as a primary care physician and age, it has the highest average values.
Group 2, labelled “Unfavourable”, quantifies moderate wine consumption as drinking no glasses or half a glass of wine per day (over 46%) and its own wine consumption is very low. Almost 4 in 10 of the primary care physicians in the group never drink wine or do so less than once every three months. Once again, a relationship is seen between consumption patterns and attitudes, which in this group are unfavourable. The group is equally balanced in terms of gender, and with respect to years worked as a primary care physician and average age, its members are generally younger.
Group 3, labelled “Ambivalent”, quantifies moderate wine consumption as one glass per day (nearly 46%) and its own wine consumption is similar to the average of the total sample, i.e., the data show an intermediate level of consumption. The average age of its members and the years they have worked as primary care physicians are also similar to the averages of the total sample. In terms of gender, this group has the most women, who account for over 7 in 10 of its members.
4. Discussion
As seen in Table 1, the literature on wine’s cardiovascular benefits is extensive, more so than for studies focusing on other areas. This is in line with this study’s findings, which show an evident association of wine, specifically red wine, with heart-healthy effects (Gepner et al., 2015). Similarly, a study by Chang et al. (2016) concludes that the majority view is that red wine is the healthiest alcoholic drink, and that this view is independent of factors such as gender. The antioxidant effect of polyphenols, specifically resveratrol, and the synergy between the alcohol and polyphenols in red wine are largely behind the perception of therapeutic benefits. In addition, Chikezie et al. (2015) have described the irrefutable influence that reactive oxygen and nitrogen species have on the physiopathology of diabetes. The findings, however, do not establish the precise therapeutic effects of antioxidants, which need further clarification. With a view to creating specific therapeutic guidelines in clinical practice, primary care physicians still seem to undervalue the beneficial effects of moderate wine consumption on diabetes. Similarly, a review of various studies reveals no conclusive evidence indicating that light-to-moderate alcohol consumption adversely affects cognition and increases the risk of dementia (Reale et al., 2020).
Finally, it should be noted that moderate consumption of white wine wasn’t associated with any potential benefits. One possible explanation for this is that the amount of resveratrol, one of the polyphenols in wine that has received the most attention, can vary from 0 to 2.9 mg/l in red wine but from just 0 to 0.06 mg/l in white wine (Leighton & Urquiaga, 2007).
In cluster analysis, it should be noted that all three groups share the attitude that “It is important to limit the amount of wine consumed”. The “Wine in Moderation” campaigns carried out by the wine industry in 2020 to encourage moderate consumption may thus have been rooted in the general consensus among primary care physicians regarding the importance of moderation. Some authors, such as Xiang et al. (2014), have questioned the view that wine’s health benefits stem solely from the presence of resveratrol and its role as a powerful antioxidant, arguing that wine’s health-promoting effects are more complex in nature and result from the multiplex composition of the drink itself. Moreover, although a growing body of evidence corroborates the health benefits of wine, all of it stresses the importance of moderate consumption in order for them to be realized, and some authors question whether overoptimism may have come into play (Chikezie et al., 2015). From a public health perspective, primary care physicians should implement various measures to address the limitation of wine consumption. Firstly, it is essential to educate patients about moderate wine intake (Hrelia et al., 2022), providing a clear message tailored to their sociocultural backgrounds. Increased knowledge regarding wine allows individuals to make more responsible choices and thus limit their consumption (Jaud et al., 2022). Secondly, physicians should incorporate prevention into their daily practice through regular assessments (DiMartini et al., 2022). Such intervention ought to be brief and efficient to ensure effectiveness and patient acceptance.
This study’s results indicate that Spanish primary care physicians associate beneficial health effects from wine with the specific type of wine consumed. Red wine stands out in particular for its strong association with cardiovascular benefits. White wine, on the other hand, isn’t associated with any health benefits in this study.
The doctors also show a generally favourable view regarding alcoholic drinks, in particular wine, although they believe it is vital to limit the amount of wine consumed. With respect to patients’ ability to consume wine in moderation, they seem to show doubt or distrust. Furthermore, the segmentation performed based on their attitudes towards wine consumption and its relationship to health identifies three different groups of physicians. For the most part, the physicians perceive moderate consumption as beneficial for health. However, in their attitudes towards their patients they seem to display distrust. It may be that doctors see it as risky to advise patients to drink wine because they fear this might be taken as a licence to consume other alcoholic drinks.
The “Favourable” group consists of older, more experienced physicians, the majority of whom are male, and is the group whose own wine consumption is most frequent. This group likely regularly includes wine in a diet based on a slower, more elaborate style of eating and food preparation. The “Ambivalent” group takes a favourable view of the health benefits of moderate wine consumption and stands out for having the highest share of women and perhaps a more prudent attitude. It is true that information about alcoholic drinks is ambiguous and that clinical trials have been fairly inconsistent. Moreover, it is difficult to form a general view due to the varying nature of patients’ characteristics and pathologies, which makes it hard to establish universal prescription guidelines. Finally, the members of the “Unfavourable” group are the youngest and consume the least wine. They may have a different culture, with water and alternative drinks serving as their main beverages, or diets based on faster, more ready-made food.
The results of this study show that the attitudes and perceptions of primary care physicians in Spain regarding the health benefits of wine use are related to their own definition of “moderate” wine intake and their personal wine-drinking behaviours. However, there are two groups of professionals who are misinformed. The “Favourable” segment supports a level of moderate wine consumption that exceeds and may be more harmful than the limits suggested by studies, which recognise health benefits at a consumption level of one glass or less per day for women and two glasses or less per day for men. Indeed, moderate wine consumption, defined as one to two glasses per day as part of the Mediterranean diet, has been positively associated with promoting human health, as well as with the prevention and prognosis of diseases (Pavlidou et al., 2018). The discrepancy regarding what constitutes moderate wine consumption may be influenced by personal factors specific to the physician, such as age or sex. A study conducted among primary care professionals in Spain found an association between being a male and a consumer of alcohol, and being female and a teetotaller (Rodríguez Fernández et al., 2001). Moreover, physicians’ own lifestyles, including their higher frequency of wine consumption, could influence the advice they provide. In any case, excessive consumption poses health, social and economic risks. Therefore, the wine industry should engage with primary care physicians by providing training and educational materials grounded in scientific evidence (González Hidalgo et al., 2015) rather than personal perceptions, for example. Public recognition could also be given to those physicians who advocate for responsible practices. It is important to note that primary care physicians play a pivotal role as leaders in health knowledge.
On the other hand, the “Unfavourable” segment overlooks the benefits of moderate wine consumption. The attitudes and perceptions within this group may lead to patient recommendations that favour a more restrictive intake or complete abstinence. This may stem from the complexity of the risk relationship between alcohol and health, which may confuse physicians when deciding whether to recommend its consumption (Liu et al., 2022). Furthermore, wine analysis clearly indicates that it differs from other alcoholic beverages, with moderate consumption not only failing to elevate the risk of chronic degenerative diseases, but also being linked to health benefits, especially when included as part of a Mediterranean diet. As previously mentioned, it is evident that all educational efforts must be directed towards preventing excessive consumption, particularly among the youth (Hrelia et al., 2022). Therefore, it is crucial to communicate to this demographic that the aim is not to promote red wine consumption for health benefits, but rather to prevent discouraging moderate consumption based on misconceptions or misinterpretations (Wojtowicz, 2023). The wine industry should inform them of the benefits of moderate red wine consumption, which are well-supported by scientific literature (Castaldo et al., 2019). Indeed, Fradera and Hammer (2023) indicate that light-to-moderate wine consumption positively influences cardiovascular mortality. Furthermore, the World Health Organisation (WHO) and the World Cancer Research Fund (WCRF) assert that one third of cancers could be prevented through the adoption of a healthy lifestyle, which includes avoiding smoking, maintaining a normal body weight, engaging in physical activity, avoiding excessive alcohol intake and following a nutritious diet. In short, within the “Unfavourable” segment, perhaps the excessive caution in their advice may stem from a lack of knowledge, which should be grounded in scientific evidence. However, such evidence is often ambiguous, leading to a lack of decisiveness in physicians’ recommendations. In addition, as previously noted, it is essential to understand the patient’s perception of what constitutes moderate wine consumption. However, on the other hand, eliminating wine consumption altogether could be counterproductive, since this may lead the patient to turn to other, less healthy alcoholic beverages.
Based on this study’s findings, the wine industry could claim a relationship between moderate wine consumption and health, particularly for red wine and the possible prevention of cardiovascular disease. However, the findings would need to be communicated to consumers without detracting from their perception of wine as a fun and festive drink. It could be useful to increase contact between the industry and primary care physicians, who could provide information on relevant new developments. In other words, the sector could work alongside health professionals to convey the importance of moderate, responsible consumption. Furthermore, the physicians’ agreement regarding the need to limit wine consumption adds weight to Spanish and European campaigns to raise awareness of consumption patterns that are compatible with a healthy lifestyle that promotes wellbeing. These findings bear out the wine sector’s “Wine in Moderation” initiative.
As regards areas for future study, closer consideration is merited by the unfavourable attitude shown by younger physicians toward the health effects of moderate wine consumption. Despite scientific evidence to the contrary, they display a negative attitude which may be rooted in various factors that warrant further study: lack of familiarity with wine, a different type of diet and style of eating, etc. Analysis could also be made of deficiencies in the information on moderate wine consumption available in university programmes, public healthcare systems and health protection bodies for the purpose of explaining to young professionals the subtleties and implications of wine consumption and providing them with support when advising patients. Finally, it should be noted that this study has some weaknesses, such as not taking into account the impact of COVID-19 because fieldwork was carried out before the onset of the pandemic. The survey was also conducted at a scientific conference and despite the randomness of the sample, the physicians surveyed had all attended a medical conference organized by the Spanish Society of General and Family Physicians (SEMG). It should be stressed, however, that attendance of such events is very frequent among the group studied.