The Science of Healthy Eating #3: How to Get the Most Health Benefits from a Vegan or Vegetarian Diet
In recent years, more and more people are choosing to eliminate animal products from their diet, motivated by ethical, environmental, and health reasons. At the same time, the number of scientific studies on the topic has increased exponentially. In this article, I briefly summarize how to structure a healthy vegan or vegetarian diet and what health benefits it can offer.
Benefits of a Plant-Based Diet for Cardiometabolic Health
Since the 1980s, vegetarian diets have been the subject of a growing number of studies, and research continues to explore their effects in more depth.
Because this is such a vast topic, I’ll definitely return to it in future articles. For now, here’s a short summary of the main health benefits observed among vegetarians, based on the conclusions of the Academy of Nutrition and Dietetics in their Position Paper.
Improvements in abdominal obesity, blood pressure, lipid profile, and blood glucose.
Reduction in inflammation, oxidative stress, and formation of atherosclerotic plaques.
Lower risk of cardiovascular disease, especially in vegan diets.
Low-fat vegan and vegetarian diets, combined with other lifestyle factors (such as not smoking and weight loss), have been shown to reverse atherosclerosis.
Reduced risk of type 2 diabetes in lacto-ovo vegetarians and vegans.
18% lower overall incidence of cancer in vegetarians.
In the next article, I’ll explore another fascinating and evolving topic: how lifestyle influences the mechanisms of aging, with a special focus on the benefits of a vegan diet.
How to Structure a Healthy and Balanced Vegan Diet
This brings us to a key question: how should a vegan or vegetarian diet be structured to be truly balanced? Is it enough to simply eliminate animal products and replace them with plant-based alternatives? The answer is obviously no.
A healthy plant-based diet should have the same foundation as the Mediterranean or Nordic diet: whole grains, legumes, vegetables, and fruits, with as little processing as possible, plus special attention to certain foods to ensure an adequate intake of all macro- and micronutrients.
So if you start from a true Mediterranean diet, the differences are actually minimal.
The VegPlate
For more details, I recommend anyone who already follows or wants to adopt a vegan or vegetarian diet to check out the VegPlate.
It’s a comprehensive summary of two articles published in the Journal of the Academy of Nutrition and Dietetics in 2017 and 2018. Since this journal is the official publication of the most authoritative scientific society in the field of human nutrition, these publications effectively recognize the VegPlate method as a reliable framework for building an optimal plant-based diet.
Here are just a few additional thoughts of my own.
Legumes and Their Derivatives
The group that replaces meat and fish is, of course, legumes in all their forms. Canned or frozen varieties are perfectly fine, as are legume flours (such as chickpea), legume pasta, tofu, and soy granules.
These are some of the most versatile foods available, and it’s easy today to find delicious recipes using legumes in starters, mains, and even desserts! Honestly, I recommend everyone, vegan or not, to start experimenting with them: I’m confident you won’t regret it.
Soy “milk” and yogurt are also part of this group. If you enjoy them, they’re excellent choices for breakfast or snacks. They’re often fortified with 120 mg of calcium per 100 ml, the same amount found in cow’s milk. They’re also great in dessert recipes.
Nutritional Yeast
Nutritional yeast is a deactivated yeast derived from the same Saccharomyces cerevisiae strain used in baking. Unlike active yeast used in leavened products, nutritional yeast is dried in a way that eliminates its fermentative properties, making it unsuitable for baking.
Of course, it’s not essential and not everyone may like it. But in my experience, even many omnivores enjoy it, so I suggest giving it a try, regardless of your dietary preferences.
Why?
It has an umami, cheese-like flavor and is a great flavor enhancer.
It contains no cholesterol or saturated fats.
It’s rich in protein (about 50%), folate, B vitamins, and β-glucans, key prebiotics linked to better immune response and greater satiety.
Calcium-Rich Foods
In a plant-based diet, calcium isn’t concentrated in a single food group, as it is with dairy, but is distributed across various plant foods. After all, even other animals, including cows, get their calcium from plants. Top plant sources include leafy greens, legumes, nuts, and dried fruits.
Herbs and aromatic plants are also surprisingly rich in calcium and iron. We may use small amounts, but their contribution can still be meaningful: just 5 g of dried basil, for example, contains nearly as much calcium as 100 ml of milk.
Also worth noting that a good amount of calcium can come from water, both bottled and tap.
Iodine
The main source of iodine, even for omnivores, is iodized salt, since meeting daily needs through fish alone would require eating it every day.
Seaweed is generally very rich in iodine, but its content varies greatly. It’s also easy to exceed the daily requirement. For these reasons, seaweed is not considered a reliable source of iodine.
So, if you follow a vegan or vegetarian diet and want to limit your salt intake, an iodine supplement is a good option. For adults, the recommended daily intake is about 150 mcg.
Differences Between Vegan, Vegetarian and Flexitarian Diets
As shown in the VegPlate, the only difference between a lacto-ovo vegetarian diet and a vegan diet is the occasional inclusion of eggs and dairy in place of legumes. Even then, it’s better to choose lower-fat options and consume them in moderation.
Flexitarians, on the other hand, mostly follow a vegetarian or vegan diet but occasionally eat meat or fish.
One important clarification: vitamin B12 must always be supplemented, not only in vegan diets, but also in vegetarian and flexitarian ones. Fortified or fermented foods are not considered reliable sources.
Conclusion
If you’re thinking about transitioning to a plant-based diet and still have some doubts, I suggest consulting a knowledgeable professional, who can answer your questions and offer practical advice tailored to your needs.
That said, a vegan or vegetarian diet is no more at risk of deficiencies than an omnivorous one. Any diet, in order to preserve health over the long term, must be well-balanced. In fact, many omnivores today unfortunately do not follow a balanced diet and are therefore prone to multiple nutritional deficiencies.
Discover more:
Sources
Academy of Nutrition and Dietetics, 2016. Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics, 116(12), pp.1970–1980.
Agnoli, C., Baroni, L., Bertini, I., Ciappellano, S., Fabbri, A., Papa, M., Pellegrini, N., Sbarbati, R., Scarino, M.L., Siani, V. et al., 2017. Position paper on vegetarian diets from the Working Group of the Italian Society of Human Nutrition. Nutrition, Metabolism & Cardiovascular Diseases, 27, pp.1037–1052.
Baroni, L., Goggi, S. and Battino, M., 2018. VEGPlate: A Mediterranean-based food guide for Italian adult, pregnant and lactating vegetarians. Journal of the Academy of Nutrition and Dietetics, 118(12), pp.2235–2243. https://doi.org/10.1016/j.jand.2017.08.125
Glenn, A.J., Viguiliouk, E., Seider, M., Boucher, B.A., Khan, T.A., Blanco Mejia, S., Jenkins, D.J.A., Kahleová, H., Rahelić, D., Salas-Salvadó, J. et al., 2019. Relation of vegetarian dietary patterns with major cardiovascular outcomes: A systematic review and meta-analysis of prospective cohort studies. Frontiers in Nutrition, 6, p.80.
Key, T.J., Papier, K. and Tong, T.Y.N., 2021. Plant-based diets and long-term health: findings from the EPIC-Oxford study. Proceedings of the Nutrition Society, 81(2), pp.190–198. https://doi.org/10.1017/S0029665121003748
Termannsen, A.-D., Clemmensen, K.K.B., Thomsen, J.M., Nørgaard, O., Díaz, L.J., Torekov, S.S., Quist, J.S. and Faerch, K., 2022. Effects of vegan diets on cardiometabolic health: A systematic review and meta-analysis of randomized controlled trials. Obesity Reviews, 23(9), e13462. https://doi.org/10.1111/obr.13462
Yu, L., Gao, Y., Ye, Z., Duan, H., Zhao, J., Zhang, H., Narbad, A., Tian, F., Zhai, Q. and Chen, W., 2024. Interaction of beta-glucans with gut microbiota: Dietary origins, structures, degradation, metabolism, and beneficial function. Critical Reviews in Food Science and Nutrition, 64(27), pp.9884–9909. https://doi.org/10.1080/10408398.2023.2217727