Australia’s Dietary Guidelines recommend we ‘enjoy a wide variety of nutritious foods’ every day (1).

And they’re not alone! Across the globe, improving dietary diversity is widely recognised as a vital part of healthy diets. A varied diet can help meet nutrient needs and reduce the risk of major chronic diseases (like cardiovascular disease, type 2 diabetes and certain cancers), as well as malnutrition (2).

Dietary diversity is defined as the number of different food groups or foods consumed in a given period (2).

The trick is to achieve variety through nutritious, core foods, rather than less-healthy options.

This is because when your diet includes an excess of more highly-processed foods, refined grains and sugar-sweetened drinks (which are easier to access now than ever before), it’s linked with weight gain and obesity (3).

So, the key is eating a wide variety of foods across the five core food groups, and a range of foods within each of these (think: different types and a range of colours). 

Did you know? The United Nations uses a dietary diversity score (DDS) to reflect nutrient adequacy (2). Diet quality indices (or scores), such as the Dietary Guidelines Index and the Healthy Eating Index, have also been developed to assess diet healthfulness or adequate food consumption (4,5).

Why is diversity important?

Nutritious, whole foods contain a complex variety of nutrients and bioactive components, such as phytochemicals – which work together to protect against certain diseases.

And scientific studies show that eating a wide variety of these foods is linked with a range of health benefits (1,6,7). These include:

• Lower risk of developing type 2 diabetes
• Reduced risk of metabolic syndrome
• Lower risk of heart disease
• Lower risk of malnutrition, and
• A longer life expectancy.

A 2021 study, involving more than 3,000 elderly Chinese people, found that a more diverse diet contributed to healthier aging (8). A ‘higher dietary diversity’ score was linked with better cognitive function, fewer physical functional limitations, and less psychological stress.

Research by the American Gut Project found people who ate 30 or more different plant foods a week had more favourable gut microbiome diversity, compared to those who had 10 or less.

Why you should mix up your nuts

A variety of nuts can (and should) be included in a healthy diet!

Overall, nuts have relatively similar macronutrient (protein, carbohydrate and fat) profiles, but different nuts have slightly different amounts of vitamins and minerals. For instance:

• Walnuts, pecans and macadamias are richer in plant-based omega-3 fatty acids
• Almonds are highest in vitamin E
• Brazil nuts contain higher levels of selenium and magnesium
• Pistachios have the highest amount of melatonin
• Pine nuts are highest in manganese
• Cashews have the most iron and zinc
• Chestnuts and hazelnuts are highest in dietary fibre.

Eating a variety of nuts will diversify the nutrients in your diet. But most Australians (98%, in fact) don’t consume nuts regularly enough, and in sufficient amounts, to reap the benefits (9).

Five ways to boost diet diversity

• Buy one or two plant-based foods (such as nuts, seeds, vegetables, fruit, whole grains and legumes) each week, that you didn’t buy the week before.
• Plan to cook at home more often to try new recipes and ingredients.
• Choose foods based on seasonality, with each season an opportunity to try different, fresh produce.
• Add goodness to your go-to meals and snacks – such as a handful of crunchy nuts to a favourite salad or blended into a smoothie.  
• Explore traditional foods from different cultures.

Tip: Nut ‘meals’ or ground up nuts can be used as an alternative to regular flour.

Of course, the power of food is so much more than the nutrients they contain! Trying a wider variety of foods also means new tastes and textures, new stories and cultures, and new connections with food and the people we share it with.