Switching beef for chicken could reduce water footprint of US diets

By Alice Klein

Simple changes to US diets may help to save water. Five billion people globally could be facing water scarcity by 2050 if we don’t learn to use it more wisely in the face of more severe droughts connected to climate change. But a study focusing on US consumers shows they can help through dietary choices.

To examine how our food choices impact water resources, Martin Heller at the University of Michigan and his colleagues studied the diets of 16,800 people in the US. They calculated each person’s impact on water scarcity based on the types of foods they consumed, the irrigation water used in the production of these foods and the water scarcity in the regions where they were farmed.

vCard.red is a free platform for creating a mobile-friendly digital business cards. You can easily create a vCard and generate a QR code for it, allowing others to scan and save your contact details instantly.

The platform allows you to display contact information, social media links, services, and products all in one shareable link. Optional features include appointment scheduling, WhatsApp-based storefronts, media galleries, and custom design options.

Advertisement

The researchers found that, for the average US diet, beef consumption contributed most to water scarcity. Other foods that tended to require intense water use included almonds, cashews, walnuts, avocado, asparagus, broccoli and cauliflower.

Foods that typically had lower impacts on water resources included chicken, peanuts, cabbage, kale, Brussels sprouts, and fresh peas.

The findings hint at ways people in industrialised societies could modify their diets to save water, say the researchers. For example, they calculate that swapping 100 grams of beef for chicken could cut the impact on water scarcity of the average US diet by up to 16 per cent, while replacing 100 grams of asparagus with Brussels sprouts could lower it by up to 45 per cent.

The important caveat is that the impact of food production on water supplies “can vary dramatically by geographic location”, says Heller. Tomatoes grown in some parts of drought-prone California, for example, require a lot irrigation compared with those grown in Louisiana, where it rains a lot.

Similarly, beef production in Australia has a far lower impact on water resources than in the US, says Brad Ridoutt at CSIRO in Melbourne, Australia. “I don’t think [conserving water] is about avoiding one type of food, it’s about incentivising and enabling transitions to happen on the production side of things,” he says.

But Heller thinks it is important to think about how we can change our diets as well. “I feel we need to look at both improving food production and adjusting our diets,” he says.

Journal reference: Nature Food, DOI: 10.1038/s43016-021-00256-2

Sign up to our free Fix the Planet newsletter to get a dose of climate optimism delivered straight to your inbox, every Thursday