7 myths about the vegan diet
Do we really need to eat meat and fish to get enough protein? Does following a vegan diet pose more health risks or benefits? Let’s analyze the 7 main myths about vegan nutrition in light of the latest scientific evidence.
1. A diet without animal products poses greater health risks because it is lacking in certain micronutrients.
To understand the difference between plant-based and animal-based foods, it’s helpful to start with a key concept in biology: the trophic chain.
All organic matter on Earth is produced by autotrophic organisms, capable of transforming inorganic compounds into organic ones through photosynthesis. This group includes plants, algae, and some bacteria. Animals, on the other hand, are heterotrophic, meaning they do not produce organic matter directly but obtain it by consuming other organisms.
Consequently, animal-based products do not contain any essential substances for us that are not already present in plants or that our bodies cannot produce on their own.
Consuming plants directly means skipping a step in the food chain and obtaining the nutrients at their source.
The only nutrient found in animal products but absent in plants is vitamin B12. However, this is not synthesized by animals but by bacteria.
Vitamin D is also not present in plants; its form is only found in certain mushrooms. However, calling it a vitamin is not entirely accurate, because our body can synthesize it with sun exposure, which is why it should be considered a hormone.
2. All vegans are deficient in vitamin B12.
As mentioned earlier, vitamin B12 is produced by bacteria and other microorganisms found in the soil and water. Additionally, some inhabitants of our gut microbiota can produce it, but this occurs in the colon, where we are unable to absorb it.
B12 must absolutely be supplemented by those following a vegan, vegetarian, or flexitarian diet (which involves occasional consumption of animal products). Without supplementation, all of these groups are at risk of deficiency. However, it is very rare to find vegans who are unaware of this issue and who do not take a supplement.
It’s important to remember that nowadays, vitamin B12 always comes from bacterial synthesis. The vast majority of farmed animals do not live in their natural conditions and do not obtain B12 from water and soil ingested with grass, but from supplements added to their feed.
For this reason, the amounts found in meat, fish, dairy, and eggs are variable and not always sufficient to meet the required intake. A good practice would be to monitor B12 levels even in omnivores, in order to intervene promptly and supplement it when necessary.
3. A diet without animal products is protein-deficient.
If we were to conduct a street survey asking where proteins are found, 90% of respondents would likely say “in meat, fish, and eggs.” The truth couldn’t be further from this statement, as practically all foods contain proteins, except for those obtained through extraction, such as oils, sugar, etc.
The only difference lies in the quantity and composition of amino acids, the 20 different “building blocks” that make up all the proteins in our bodies.
Today, we are well aware of the protein and amino acid content in most foods. For example, legumes contain a similar percentage to meat (20-25%), with soy reaching 37%. Whole grains contain an average of 10-15%. So, I can assure you that when calculating balanced, normocaloric vegan diets, it is practically impossible not to meet the protein requirements.
In a dedicated article, I will go into more detail on this topic, explaining why animal proteins are still considered ’noble,’ what limiting amino acids are, and how the absorption of plant-based proteins differs.
For now, I conclude by quoting the official position of one of the most important scientific organizations worldwide, the Academy of Nutrition and Dietetics, which already concluded in 1997, and subsequently reiterated, that plant-based diets provide adequate or even superior protein intake compared to recommendations, provided that caloric intake is sufficient and there is a variety of foods consumed.
This same position is also confirmed by other major scientific associations in the field of nutrition, including the Italian Society of Human Nutrition (SINU), the Dietitians of Canada (DoC), the German Nutrition Society (DGE), and the British Dietetic Association (BDA).
Naturally, it’s important to note that restrictive vegan diets, such as fruitarian diets, are not balanced and tend to be deficient in proteins and other nutrients.
4. Dairy products are necessary for bone health.
The idea that dairy products are essential for strong bones is widely spread, but it is not accurate. Calcium is certainly an essential mineral, but milk and its derivatives are not the only available source.
Moreover, epidemiological studies show that a high consumption of dairy is not associated with a lower incidence of fractures; on the contrary, in some cases, an increased risk of fractures has been observed in women for each glass of milk consumed daily, along with higher all-cause mortality.
Many plant-based sources provide equal or greater amounts of calcium compared to milk, with the added benefit of providing fiber, antioxidants, and beneficial fatty acids. These include various types of leafy green vegetables (such as kale and arugula), legumes, nuts, and oilseeds (especially sesame and almonds), which provide excellent amounts of calcium, often more bioavailable than that found in milk.
Additionally, to further facilitate meeting the requirements, it is possible to include plant-based drinks and other calcium-fortified foods, as well as mineral waters, naturally rich in this mineral.
It’s important to understand that bone health, however, does not depend solely on calcium, but on a combination of factors, including vitamin D, magnesium, protein, and physical activity.
Undoubtedly, one of the main factors for strong bones is physical activity, particularly weight-bearing exercises on the skeleton. Walking uphill, doing weight training, or carrying a backpack helps stimulate bone density, reducing the risk of osteoporosis. Bones, like muscles, strengthen with use.
5. Only adults can follow a vegan diet.
The myth that only adults can follow a vegan diet often arises from a lack of knowledge on the subject or from examples of unbalanced diets.
In fact, just like the Academy of Nutrition and Dietetics, other major scientific associations in the field of nutrition have also concluded that a fully plant-based diet, if well balanced, can meet nutritional needs at all stages of life, providing all essential nutrients for optimal growth and development.
Naturally, as with any other type of diet, it is crucial that the diet is balanced and includes adequate sources of protein, iron, calcium, zinc, vitamin B12, vitamin D, and omega-3 fatty acids.
For this reason, it is always advisable to seek the support of a professional experienced in pediatric nutrition.
6. A plant-based diet is not recommended for people with chronic diseases.
This is the easiest myth to debunk because numerous scientific studies indicate exactly the opposite. A plant-based diet can be beneficial for managing and preventing many chronic diseases, as long as it is structured to ensure the correct intake of all essential nutrients.
Various international guidelines list among the primary recommendations for preventing conditions such as type 2 diabetes, hypertension, cardiovascular diseases, and some forms of cancer a high consumption of whole grains, legumes, vegetables, and fruits. The fiber, antioxidants, and phytochemicals found in plant foods help improve metabolic health, reduce inflammation, and promote better weight control.
It should be emphasized that, in the case of one or more chronic conditions, it is always advisable to consult a nutrition professional to tailor the diet to each specific case.
This is certainly a very broad topic, and I will return to it several times in this blog to delve deeper into at least some important aspects related to both the prevention and nutritional treatment of certain diseases.
7. A vegan diet is monotonous and tasteless.
One of the most common misconceptions about plant-based eating is that it is boring and lacks flavor. In reality, a vegan diet offers an extraordinary variety of tastes, colors, and textures, thanks to the richness of fruits, vegetables, legumes, grains, seeds, and nuts available.
Cuisines from around the world offer countless traditional plant-based dishes, from spicy Asian soups to colorful Mediterranean plates, to flavorful Indian curries. The key to a tasty vegan diet is creativity in combining ingredients and spices, along with experimenting with new foods and recipes.
Scientific studies show that a well-planned plant-based diet can not only be varied and satisfying, but it can also contribute to greater dietary diversity compared to an animal-based diet.
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Sources:
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