Legumes: ultimate weapons against climate change in 7 combats 

The Egyptians venerated them. They gave beans a place alongside the belongings of their deceased, to assure their peers of a most promising afterlife. When Octavian conquered Egypt in 30 BC, the Romans returned to Rome with a great booty: the obelisk in St. Peter’s Square and 1,000 tons of lentils! In ancient Greece, in addition to serving as food, they were used to cast votes in the Agora. In South America, they also served as currency. 

Legumes have been part of our lives for 90 million years and comprise more than 20,000 species that are spread all over the planet. Their versatility has allowed a wide variety of cultures to include them among their traditional recipes, from hummus in the Mediterranean or daal in India, to beans with rice in Latin America. They are rich in flavour and nutrients. And they can save the future of our planet. 

In addition to their valuable contribution to the food pyramid, lima beans, broad beans, chickpeas, lentils and split peas play a key role in feeding the world’s growing population, which is expected to reach 9 billion by 2050. If this prediction comes true, FAO estimates that agricultural production will have to increase by 70% by 2050. How will we achieve this in a context of climate crisis? Let’s look at how legumes can help us win this battle: 

1. Their production makes very efficient use of water 

Did you know that 70% of the world’s accessible water is used for agriculture? One of the great advantages of growing legumes is the low amount of water required for their production. 

Keep in mind that producing one kilogram of beef (animal protein) requires 10 times more water than producing 1 kg of lentils (vegetable protein). This fact is even more relevant when we also consider that 40% of what agriculture produces is used to feed livestock. Can you imagine how much water we would save if we moderated our meat consumption? 

2. No nitrogen fertilizers are required 

Nitrogen is an important component of chlorophyll, the compound through which plants perform photosynthesis. Most of them are not capable of capturing the nitrogen present in the atmosphere… but legumes are. They carry bacteria in their nodules that fix nitrogen from the atmosphere in the soil so that it can later be used in the nutrition of other plants. As they are self-sufficient, they do not require nitrogen fertilizers, the use of which has negative consequences such as water pollution. Here are more details. 

3. They regenerate soils naturally  

Their ability to fix nitrogen in the soil is an advantage for the plant, but also for the soil. Yes, legume production enriches the soil and fertilizes the following crop in a natural way. How much? According to FAO, legumes can add 30 to 40 kg of nitrogen per hectare of land. Not only that, but they contribute to maintaining and increasing the vital microbial biomass of the soil and some varieties are even capable of releasing phosphorus into the soil. Finally, they increase the capacity of soils to absorb carbon. 

These advantages make legumes an ideal choice for crop rotation, increasing productivity and soil diversification. And this is essential because, at present, one third of our planet’s soil is moderately to highly degraded. 

Karachi, Pakistan (FAO)

4. They help to decarbonise the planet 

It is a statistical fact: livestock and agriculture emit almost one third of the world’s total CO2. How? Fertilizers used in agriculture release greenhouse gases both in their manufacture and in their use, so promoting the cultivation and consumption of legumes is equivalent to reducing the use of fertilizers and thus helping to decarbonise the planet. 

5. They are amazingly versatile 

According to FAO, legumes have a vast genetic diversity, which allows better varieties to be adapted for cultivation to climatic variability. An aspect that contributes to food security in areas prone to floods, droughts and other extreme weather conditions. 

6. They save energy 

Legumes have the advantage of requiring minimal processing. Also, they do not need to be refrigerated and are very easy to transport. 

7. They are the key to combating food waste 

Legumes can be stored for many months (even years!) without spoiling, which reduces the chances of them ending up in the garbage. This is no insignificant matter, especially if we take into account that one third of the food that we produce for our consumption is lost or wasted. In addition, the few residues generated in their cultivation can be used as fodder to improve livestock diets. 

Need more reasons to eat legumes?