Planetary Diet: How Changes in Diet Impact the Health of Our Planet

The planetary diet represents a contemporary approach to nourishment that takes into account the connections between dietary recommendations and the state of the environment. Its fundamental principles were outlined in a report published in January 2019 in the medical scientific journal The Lancet. Special emphasis was placed on the subject of a sustainable diet that can contribute to reducing worldwide mortality, improving human health, and addressing ecological issues related to food production and consumption.

The EAT-Lancet Commission, comprised of 37 internationally recognized scientists, produced a report on the methodologies of producing and consuming food that connects the environment to human health. It should be noted that the document was not intended to present food regulations and prohibitions. The report emphasized that identifying one diet as the ideal diet without reducing food waste and improving the efficiency of these processes is a huge mistake. One of the priorities taken into account in the environment and human health is to achieve a sustainable future by 2050. The Commission pointed out that unconsidered food production can have negative impacts on the environment, including climate change, phosphorus and nitrogen pollution of water, and loss of biodiversity. Another issue discussed by the Commission was the overuse of water in agriculture. Unbalanced management of this system can result in deterioration of water quality, erosion and salinization of soil, and loss of water habitats. The EAT-Lancet Commission also discussed the issue of limiting water consumption in its report. Unfortunately, this will be very difficult to achieve in the future, as growing nuts and legumes, as an alternative to animal protein, requires large amounts of water, and water consumption can be reduced primarily by reducing waste and improving production efficiency. On the other hand, choosing one diet, such as vegan, can lead to overuse of land and fertilizer (nitrogen, phosphorus), which can have negative impacts on the environment.

The EAT-Lancet report focuses on several key aspects of diet. Firstly, it encourages the reduction of meat consumption (particularly red meat). The commission emphasizes that the excessive intake of this protein source in Western dietary patterns leads to poor health and increases the risk of overweight, obesity, and certain non-communicable diseases. Forecasts indicate that the adoption of a diet based on red meat in conjunction with economic growth could significantly burden both human health and the environment. The second issue is the overconsumption of sweeteners, sugar, and processed foods. The commission calls for a significant reduction in the consumption of such products and highlights the necessity for further research in this area. Another strategy involves increasing the proportion of vegetables, fruits, nuts, and legumes in the diet. The report recommends reducing food losses and waste, as this currently constitutes a serious problem and requires immediate action.

The planetary diet is visually represented as a half plate filled with vegetables, fruits and nuts, and the other half with whole grain products, plant protein sources (mainly legumes), saturated vegetable fats, meat, dairy, some starchy vegetables, and sweetened foods. It is worth noting that it is flexible enough and can be adapted to individual dietary needs, taste preferences, as well as cultural traditions. According to the report, the daily calorie intake for an average adult should be 2500 kcal, taking into account factors such as age, sex, health status, and physical activity level. Overconsumption, regardless of the amount of calories, can have negative effects on both health and the environment. In short, the planetary diet should focus primarily on vegetables, fruits, whole grain products, nuts, and legumes, with only a small portion of daily intake consisting of dairy and meat protein. Processed products and sugar should be limited.

According to the sources: Healthy Diets From Sustainable Food Systems. Food, Planet, Health. An exemplary dietary plan has been published that considers 2,500 calories and provides information about specific product groups. According to the table, whole grain products, unsaturated fats, nuts, and legumes should be the main sources of calories in a planetary diet. The consumption of red meat (beef, pork, lamb) and poultry should be limited. Fish and eggs should only be a supplement. Highly processed foods and white sugar should be avoided. Excessive intake of sweetening substances can lead to overweight, obesity, metabolic syndrome, or inflammatory diseases.

A recommendation of the planetary diet is to limit the consumption of red meat. While there is a plethora of research supporting this assertion, there are also publications whose authors disagree with the EAT-Lancet Commission's findings. In a 2019 study by Leroy F. and Cofnass N., it was emphasized that a significant reduction in meat consumption does not bring as much effective benefits, and that premature suggestions can cause physical and thus health damage. Additionally, Milner J. and Green R. note that the guidelines should be adapted according to the regions of the world. Their study found that replacing animal-based foods with plant-based foods brought health benefits and contributed to a reduction in greenhouse gas emissions, but only in high-income countries. In 2020, Zagmutt F. J., Pouzou J. G., and Costard S. challenged the information contained in the EAT-Lancet Commission's report regarding the prevention of premature deaths (approximately 10 million). They revealed the weaknesses of the assumptions and methodology used in estimating mortality and emphasized that further research is necessary to develop effective dietary guidelines.

Continuously, the planetary diet, as the experts claim, requires more detailed investigations. Nevertheless, it must be remembered that it pertains to very significant matters related to human health and environmental impact. One advantage of the planetary diet is its flexibility. It does not impose strict restrictions and prohibitions in diet, thus can be regarded as a compilation of guidance that may be advantageous not only to humans but also to the planet. Its fundamental principles align with the recommendations of the leading food organizations (e.g. FAO) regarding increasing vegetable and fruit consumption and reducing meat intake. It is notable that the report published in 2019 gained both supporters and a large number of opponents and continues to stir up many controversies to this day. Therefore, it is paramount to meticulously verify the sources of scientific information, which will help avoid manipulation and disinformation in matters essential to human well-being and the state of the planet.