Is climate change making our food less nutritious?

We often hear that climate change is causing more heatwaves, floods and droughts.¹ But there’s something else going on that’s less obvious. Some fruits and vegetables now contain fewer nutrients than they did in the past. So even if they look the same on the outside, they’re providing less of what our bodies truly need. What’s going on here? Is climate change really making our food less nutritious?

In this article we’ll explore how our changing environment is having an impact on the food that ends up on our plates, as well as what this means for our health and what the solutions could be. We’ll start with a little bit of science and the role of one very important molecule: carbon dioxide. 

It’s all about carbon dioxide

Plants need carbon dioxide (CO₂) to grow. But the amount of CO₂ in the air has increased a lot. Before factories and cars, around the 18th century, it was about 280 parts per million. Today, it's over 420 parts per million, and still rising.^{2 3}

Higher carbon dioxide levels can alter how plants grow and the nutrients they contain.² And this doesn’t just affect plants. When animals eat less nutritious grass or feed, the meat and dairy they produce can also be less nutritious. Scientists are still studying how much this matters.⁴

Faster growth doesn't always mean healthier crops

More CO₂ in the air can help plants grow faster. This is because they use it in photosynthesis to turn sunlight into energy.⁵ Bigger crops might sound like a good thing, but they don’t always have the same nutritional value.

When plants grow quickly in high CO₂ conditions, they often contain more starch and sugar. At the same time, they absorb fewer important minerals like iron and zinc from the soil.⁶ A major study from the United States found that common garden vegetables, like broccoli, spinach, and carrots, had lost up to 38 percent of certain nutrients since 1950.⁷ More recent research has shown similar results in rice and wheat.⁸

Soil health plays a big role too

Modern farming methods can damage the soil, leading to degradation. Using heavy machines, too many chemicals or poor irrigation can all affect how healthy the soil is. And when soil health declines, plants can’t take up nutrients as well.⁹

So if we want to keep growing healthy food, we need to take better care of our soil as well as reducing how much CO₂ goes into the atmosphere. Healthy soil plus healthy climate means  healthy food. And healthy food means healthy people.

Less nutritious food can lead to big health problems

In 2023, around 733 million people did not have enough safe and nutritious food.¹² On top of that, more than half the global population don’t get enough vital micronutrients like calcium, iron, and vitamin C. This is due to a mix of factors including poverty, not having many different foods to choose from, and how food is grown and traded around the world. Climate change and declining crop quality are making the problem even worse. A recent study found that by 2050, 175 million more people may be at risk of zinc deficiency, and 122 million could be lacking sufficient protein in their diets.¹³

Read more about why protein matters here.

The people most affected by the changing nutrients in food are often those with lower incomes, especially those who rely heavily on a few staple crops. For example, studies show that women in rice-dependent countries, such as Bangladesh and Cambodia, may not be getting all the nutrients they need during pregnancy.^{14 15}

Giving people supplements is really helpful in this kind of situation. But supplements don’t provide the same benefits as whole foods, which also contain fibre and helpful natural compounds.¹⁶ So it would be better if people could get the nutrients they need from food. 

Find out more about supplements in this article.

What can we do to protect nutritious food?

There are three concrete actions you can take to help keep our food nutritious:

1. Support farming that restores soil health

Look for food from farms that care for the soil, these are often organic, regenerative, or agro-ecological farms. You can support them by buying directly from farmers at local markets or joining a community supported agriculture scheme (CSA). 

2. Choose nutritious, responsibly grown food

Where possible, choose food that’s fresh, local, in season, and grown with care. These options often contain more nutrients and are better for the environment. At the supermarket, look for labels such as:

• Organic
• Rainforest Alliance
• Soil Association (UK)
• EU Leaf label (EU organic farming)

Regenerative farmers also take great care of the planet while producing healthy food. But there isn’t an official certification for regenerative farming in Europe yet. Find out more here. 

3. Help reduce greenhouse gas emissions

Lowering carbon emissions is key to slowing climate change. We can support this through our eating habits by:

• Eating more plants (and a bit less meat)
• Reducing food waste
• Choosing food that’s in season

Other solutions

These are a few steps we can take as individuals, but what other ‘big picture’ solutions are out there?

1. Change the way we reward farming

Farmers are usually paid based on how much food they grow, not how nutritious it is. If we reward farmers for producing healthier crops or farming in more sustainable ways, it could shift the whole system. Governments could look into subsidies for nutritious crops grown with respect for the Earth. 

2. Invest in better crops for the future

Scientists are working to create crops that keep their nutrients even in high CO₂ conditions. This includes traditional plant breeding as well as new techniques like genetic editing.¹⁷ This could be an important solution, alongside reducing carbon dioxide emissions and taking better care of our soil. 

It’s not too late to turn things around

Climate change is not only changing the weather. It’s also changing what we eat. The nutrients in our food are starting to decline, and that could affect millions of people around the world.

But while the outlook seems rather grey, it’s not too late to do something about it. By taking care of our soils, reducing pollution, supporting sustainable farming, and choosing the right foods, we can help protect the quality of our food and our health. Even small changes in how we shop and eat can help shape a more resilient and nourishing food system.