A newly-published Australian review examined the link between dietary patterns and health outcomes, with useful insights for the next iteration of Australia’s dietary guidelines (1).

The comprehensive systematic review included 59 observational studies, published between 2001 and 2023, with a combined total of 362,263 Australian adults (≥18 years of age).

It investigated the risk of developing chronic conditions, or dying from them or from any cause, with certain dietary patterns.

Understanding the dietary patterns of Australian adults, and how these impact chronic conditions, based on the evidence to date, is a crucial step towards shifting what the Australian population eats, for the better (1).

What did it find?

Healthy dietary patterns were characterised by higher consumption of dark-yellow, green leafy, cruciferous vegetables and fruits, nuts, whole grains, tomatoes, fish, and low-fat dairy.

Higher adherence to a healthy dietary pattern was linked with:

• Improved cardiometabolic risk factors, such as obesity, insulin resistance, total and LDL-cholesterol, and pre-diabetes
• Reduced risk of pregnancy-related conditions – specifically, gestational diabetes, and hypertensive disorders

It also found that a healthy dietary pattern may reduce the risk of mental health conditions (stress, depression, anxiety), cognitive function decline, and pregnancy complications (low birth weight and preterm birth).

On the other hand, unhealthy dietary patterns were linked with an increased risk of overweight/obesity, diabetes, insulin resistance, mental health conditions, and cognitive decline.

These unhealthy dietary patterns were characterised by a higher intake of processed and red meat, takeaway foods, white bread, high-fat dairy, high-fat (such as fried and processed) potatoes, discretionary fat, sweet snacks, soft drinks, fat spreads, jam, and Vegemite.

What does this mean for Australia’s dietary guidelines?

The review of the (2013) Australian Dietary Guidelines (ADGs) (2), currently underway, represents a real opportunity to shift the eating patterns of Australians for the better.

The current revision of the ADG should consider evidence on dietary patterns, in addition to individual food items or groups, when making recommendations (1).

The existing ADGs offer guidance largely based on individual dietary components. But as people don’t eat food items in isolation, any updates to dietary guidance should incorporate the findings from dietary patterns research, say the authors of this new review.

They say recommendations based on dietary patterns offer a more realistic and practical approach.

Regular nut consumption is an integral part of many healthy dietary patterns, such as the Mediterranean diet, DASH diet, and plant-forward diets, such the EAT Lancet Planetary Health Diet.

The bottom line:

Overall, the evidence to date consistently shows that healthy dietary patterns are linked with a reduced risk of chronic conditions, including cardiometabolic risks and outcomes.

Future Australian Dietary Guidelines should incorporate findings from Australian dietary patterns research, alongside evidence on individual dietary components.

Specific to nuts, the body of evidence, which has strengthened since Australia’s dietary guidelines were last reviewed, convincingly shows that nuts are a key food within healthy dietary patterns, with an impressive range of health benefits (3).

This latest review, in which a healthy Australian dietary pattern included a higher consumption of nuts, supports this finding.