Climate change, and its current and future effects on population and planetary health, is an urgent, complex issue.

Tackling it requires massive shifts in the way we do things as a society – and this includes to our food systems (such as the way food is produced, processed, distributed, and prepared) and our diets [1, 2].

In fact, the food we eat is one of the key changes we can make to help tackle the complex issue of climate change [3]. But as individuals, it can be overwhelming to know where to start.

The good news is that transitioning towards healthier foods will generally also help you live more sustainably.

Ultimately, the degree to which dietary guidance is adopted by the population will affect the health and environmental outcomes realised [4].

Remember, all food production impacts the environment – but we need to eat. So, here’s seven steps towards healthier and more sustainable eating:

1. Eat in line with the Australian Dietary Guidelines

The food choices we make every day have a huge effect on the environment. Place your focus firmly on prioritising a variety of healthy, nutrient-rich (core) foods.

Australians currently fall short on core foods from the five food groups (like vegetables, fruit, legumes, and nuts and seeds), and overconsume ‘discretionary’ (non-core) foods (such as cakes and biscuits, and sweetened drinks) [5].

Did you know? If Australians were to switch from our current average diet, to follow the recommendations of the dietary guidelines, we’d see a 25% reduction in green house gas (GHG) emissions [6].

2. Elevate healthy plant foods

The landmark EAT Lancet Commission on Food, Planet and Health report states that a diet rich in plant-sourced foods and with fewer animal-sourced foods has both health and environmental benefits [7].

It says that plant-based dietary patterns offer the best route to reducing GHG emissions, environmental degradation, and biodiversity loss. And it suggests that the global intake of nuts, vegetables, fruit, legumes, and whole grains needs to double from current consumption levels.

Did you know? The EAT Lancet Commission’s Planetary Health Diet sets a target for nuts of 50g/day (consisting of 25g each of peanuts and tree nuts).

3. Diversify protein sources

When choosing protein foods, aim to include a variety of healthy plant and animal sourced options, based on your individual needs. Eating a more diverse range of foods from within the ‘protein’ food group makes it easier to meet nutritional needs [8].

Plant-based sources of protein, such as nuts, seeds and legumes, are vastly under-consumed in Australia [9].

4. Limit discretionary foods

More than a third of Australians’ energy (kilojoule) intake comes from nutrient-poor, energy-dense discretionary (or ‘junk’) foods [10], and these have a huge impact on the environment.

Discretionary foods account for, on average:

• 33% GHG emissions

• 35% land use

• 35% of water use

• 39% of energy use involved in producing food in Australia [11].

Good evidence tells us that Australians need to eat less foods and drinks high in saturated fat, added sugar, added salt, or alcohol (such as fried foods, most take-away foods from quick-service restaurants, cakes and biscuits, chocolate and confectionery, sweetened drinks) [12].

The more the choice of the foods within a diet includes plant, whole and seasonal foods, and the less it contains animal, highly-processed, and imported foods, the more the diet is sustainable [15].

5. Minimise food waste

Food waste directly impacts the environment, due to the amount of energy and resources that are needed to produce food. When we throw away food, we don’t only discard it, but we also waste all the resources used to make that food [13].

Sadly, Australian households throw away more than $10 billion worth of edible food (or around 20% of our groceries) every year [14].

Buying only what we need, storing food wisely, and putting food waste to good use (such as by composting food scraps) are just some of the many ways to reduce food waste.

Did you know? The best way to store nuts is in an airtight container in the fridge or the freezer, where they will stay fresh for 4-6 months. This keeps them fresher for longer, and helps prevent food waste.

6. Buy and eat only what you need

Overconsumption (even of healthy, ‘core’ foods) is a form of food waste.

It creates an avoidable environmental burden, in terms of GHG emissions, use of natural resources, and pressure on biodiversity. Buying and eating only what you need can considerably lower your individual environmental footprint.

A good place to start is to be mindful of portion sizes, and to limit energy-dense, nutrient-poor foods. The Australian Dietary Guidelines outline how much, from each food group, to aim to eat each day.

Did you know? Only 2% of Australians eat the recommended target of 30g (around a handful) of nuts every day [15].

7. Choose in-season and locally-sourced foods

Locally-grown foods can be a sustainable choice, if we choose, whenever possible, those that are in season where we live.

Locally-sourced food travels less distance from farm to plate. And becoming more aware of growing seasons means you can make purchasing decisions depending on the time of year. You can always purchase products in-season, and freeze or store them for use later.

Did you know? The Mediterranean diet, which includes nuts, has been described as an achievable dietary pattern for Australians, with health and environmental benefits [16].