This review aimed to consider and comment on a recent article on which I had the pleasure of working alongside the first author, Dr. Luciana Baroni, and in collaboration with the University of Pisa (Nutrient Composition of Four Dietary Patterns in Italy: Results from an Online Survey “the INVITA Study” published in the journal Foods 2024 Jul 2;13(13):2103).
Although Italy is the birthplace of the Mediterranean Diet, many reports show with regret that only a very limited percentage of the Italian population manages to adhere to a dietary model that truly represents it.
Confirming this finding, the Mediterranean diet is associated with an extremely low risk of developing overweight; conversely, Italy has for years recorded high rates of overweight among its inhabitants.
Vegetarian dietary patterns (for example, lacto-ovo-vegetarian and vegan) are on the rise in Western countries and, to some extent, in Italy as well, where 9.5% of the population identified as vegetarian in 2023. Although the vegetarian diet is associated with health benefits, there is speculation and false myths about its supposed nutritional inadequacy.
What the study found
The main purpose of this work was to evaluate the nutritional composition of the diet of 470 participants enrolled in an online survey (the INVITA study), who completed a weighted food questionnaire on three different days. Participants were divided into four dietary groups based on their self-reported food intake: 116 meat eaters (ME), 49 fish eaters (FE), 116 lacto-ovo-vegetarians (LOV) and 189 vegans (VN).
The LOV and VN diets proved to be particularly adequate, despite some concerns related to specific nutrients such as vitamin B12, which in vegetarian and vegan diets must necessarily be supplemented (although it is worth noting that this is a vitamin in which omnivores can also be deficient).
Compared to the ME diet, the VN diet showed a more favourable profile for fats (more polyunsaturated fatty acids and fewer saturated fatty acids), a higher presence of fibre, folate, potassium and sodium.
In the LOV and VN diets, the average intake of most key nutrients fell within the normal range expected for the Italian population, supporting the adequacy of the diets in our Italian sample.
In conclusion, the study confirms that well-planned vegetarian and vegan dietary patterns are adequate from a nutritional standpoint, as well as being healthy.
Commentary on the scientific work
Vegetarian diets, especially the lacto-ovo-vegetarian (LOV) and vegan (VN) versions, are gaining increasing popularity worldwide. The reasons behind this trend include ecological, ethical and health motivations. Reducing or eliminating animal-derived products is often seen as an advantageous solution, as it contributes not only to personal wellbeing but also to the health of the planet.
As mentioned above, the INVITA study examined the nutritional profiles of four dietary patterns followed by the Italian population: omnivore (ME), pescatarian (FE), lacto-ovo-vegetarian (LOV) and vegan (VN). Through an online survey and the completion of weighted food diaries (foods defined as x grams consumed daily) over three days, they were able to assert that the vegan diet (VN) showed a particularly advantageous nutritional profile compared to the omnivore diet (ME), as it offers:
- A higher intake of polyunsaturated fats and lower intake of saturated fats, aspects that are crucial for cardiovascular health.
- Higher content of fibre, folate, potassium and sodium, nutrients that are fundamental for overall wellbeing.
Vegetarian diets and the Mediterranean diet
An interesting aspect to emerge from the study is the role of the Mediterranean diet in shaping Italian eating habits. The Mediterranean diet, which includes abundant portions of plant-based foods such as grains, legumes, fruit and vegetables, overlaps in many respects with vegetarian and vegan diets. This could explain the absence of significant signs of nutritional inadequacy in the Italian LOV and VN groups, as many characteristics of the Mediterranean diet facilitate the adoption of well-balanced vegetarian diets.
Future implications
The INVITA study confirms that vegetarian and vegan diets can be nutritionally adequate when well planned, particularly in a context such as Italy’s, where food tradition already favours plant-based foods. However, it is essential to emphasise that nutrients such as vitamin B12 require attention, especially for those following a vegetarian or vegan diet. Supplementation of certain micronutrients (such as iron and calcium) may be necessary in some specific cases, but tends to be more necessary in the LOV diet (iron) and in the FE diet (calcium).
The study authors suggest that further well-designed observational studies could help to strengthen these findings, with the aim of providing guidelines (in addition to the American ones) that confirm the validity of these dietary patterns (more plant-based). This could prove particularly useful for those healthcare professionals (doctors and nutritionists) who have not yet had the opportunity to fully read or understand the validity and completeness of a plant-based dietary model.
In conclusion, the INVITA study offers us a further confirmation that vegetarian diets can not only be sustainable from a nutritional point of view, but can also bring benefits for health and for the environment. Adopting a well-balanced plant-based diet represents a winning choice for the future of human health and the planet.
