The body of evidence about nuts and health continues to grow. These local and international research papers, published around January 2024, corroborate decades of research about the importance of a regular handful of nuts within a healthy diet.

Metabolisable energy from nuts and patterns of nut consumption in the Australian population: A secondary analysis of the 2011-12 National Nutrition and Physical Activity Survey. (Nikodijevic et al, 2024).
This research used a systematic approach to expand a nut-specific database, to include nut form and metabolisable energy values. Using this, together with a secondary analysis of Australia’s 2011–12 National Nutrition and Physical Activity Survey, the researchers explored the metabolisable energy (kJ/day) from nuts, amongst Australian nut consumers. It found that energy intake from nuts, using metabolisable energy values, is significantly lower than when predicted using Atwater factors. In addition, this research provided insights into patterns of nut consumption in Australia.

Consumption of tree nuts as snacks reduces metabolic syndrome risk in young adults: A randomized trial. (Sumislawski et al, 2023).
This randomised parallel-group trial, over 16-weeks, included 84 young adults (aged 22–36 years) with overweight or obesity, and at least one metabolic syndrome (MetS) risk factor. They received overall guidance for weight maintenance. Some ate, twice daily, 33.5g mixed tree nuts, while others had a carbohydrate-rich snack – with the same kilojoules, protein, fibre, and sodium as the nuts. It found that daily tree nut consumption reduced MetS risk by improving waist circumference, lipid biomarkers, and/or insulin sensitivity – without requiring caloric restriction.

Mixed nut consumption improves brain insulin sensitivity: A randomized, single-blinded, controlled, crossover trial in older adults with overweight or obesity. (Nijssen et al, 2023).
In this randomised, single-blinded, controlled, crossover trial, 28 healthy older adults, with overweight or obesity, received either daily 60g mixed nuts or no nuts (control) for 16 weeks, separated by an 8-week washout period. Brain insulin sensitivity was assessed. Among the findings, nut consumption significantly improved insulin sensitivity in specific brain regions (occipital and frontal) – which may be important for the prevention of age-related metabolic and cognitive diseases. Body weight and composition did not change.

Can different types of tree nuts and peanuts induce varied effects on specific blood lipid parameters? A systematic review and network meta-analysis. (Martinez-Ortaga et al, 2023).
This study analysed the findings of 76 randomised trials to determine the effects of six types of nuts (pistachios, almond, walnuts, cashews, hazelnuts, peanuts) on specific blood lipid parameters (total cholesterol, LDL-cholesterol, triglycerides, and HDL-cholesterol). Every type of nut analyzed had a significant positive impact on some parameters, and specific nut types had enhanced advantages for certain blood lipids. The authors suggest their results endorse the use of personalized nutritional strategies to address and prevent dyslipidemia.

The cardioprotective properties of selected nuts: Their functional ingredients and molecular mechanisms. (Olas, 2024).
This paper provides an overview of the research to date on the role of nuts (mixed nuts, and select nut types) in the prevention and treatment of cardiovascular disease. It outlines the current state of knowledge on the functional ingredients in nuts, including lipids, fibre, vitamin, minerals and phytosterols – and the potential mechanisms behind their cardioprotective actions. It points out that further research is needed is in this area, relating to factors such as nut dosage and the bioavailability of the various components of nuts.

A walnut-enriched diet for 2 years changes the serum oxylipin profile in healthy older persons. (Cofan et al, 2023).
This trial investigated the effect of a walnut-enriched diet (at 15% energy, or 30-60g/day), over two years, on serum concentrations of 53 oxylipins in healthy older adults (63-79 years). Oxylipins, products derived from polyunsaturated fatty acids, play a role in cardiovascular disease and aging. It found that, compared with control (no walnuts), supplementation with walnuts increased the serum concentrations of most examined oxylipins derived from α-linolenic acid. The results add novel mechanistic evidence on the cardioprotective effects of walnuts.

Effect of walnut consumption on markers of endothelial function in adults: A systematic review and meta-analysis of randomized controlled trials. (Hsu et al, 2024).
This research collated the findings of six trials (involving 250 participants) on the effect of walnut consumption on endothelial function. Walnut intake significantly increased flow-mediated dilation (FMD), but did not impact the other markers assessed – intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and stimulus-adjusted response measure (SARM). The authors suggest walnuts may reduce cardiovascular disease risk by improving FMD. But they say further studies are needed into the effect of walnut intake on endothelial function.

Nutritional interventions for male reproductive health: A comprehensive review on the impact of almonds, walnuts, and cashew nuts. (Hamza et al, 2024).
This review suggests a potential link between almonds, walnuts, and cashew consumption, and improved male reproductive health. This is thanks to the variety of bioactive compounds, including vitamin E, folate, zinc, copper, omega-3 fatty acids, and polyphenols they contain, which may help improve sperm production and quality, and protect against oxidative stress. These nuts may also help reduce inflammation – a known contributor to reproductive disorders and infertility in males. However, further well-designed clinical studies are needed in this area.

Nuts, vegetables, fruits, and protein dietary pattern during pregnancy is inversely associated with risk of childhood allergies: A case–control study. (Adineh et al, 2024).
This case-control study, involving 244 Iranian women, explored the potential link between major dietary patterns during pregnancy and allergies in young children. Three major dietary patterns were identified among study participants. Greater adherence to a ‘Nuts and seeds, vegetables, fruits, and protein’ dietary pattern during pregnancy was linked with lower odds of allergic disease in offspring at one year of age. Overall, it suggests that maintaining a healthy diet, rich in nutrients and anti-inflammatory compounds, in pregnancy may decrease risk of allergies in offspring.

A narrative review on strategies for the reversion of prediabetes to normoglycemia: Food pyramid, physical activity, and self-monitoring innovative glucose devices. (Rondanelli et al, 2023).
This narrative review describes evidence for an ‘optimum dietary treatment’ for people with pre-diabetes, and offers a food pyramid for this population. Specific to nuts, it advises 30g every day. The paper describes several nuts and prediabetes intervention trials, and concludes that the consumption of nuts (at an average dose of 30g per day) is protective against insulin resistance, impaired fasting glucose, and HbA1c.

A review of healthy dietary choices for cardiovascular disease: From individual nutrients and foods to dietary patterns. (Chen et al, 2023).
This review sums up the evidence on the effects of individual macronutrients, whole foods, and dietary patterns on the risks of cardiovascular disease (CVD). Specific to nuts, it says compelling evidence shows nut intake confers protection against CVD, and ‘increasing nut consumption should be encouraged as a crucial part of a healthy dietary pattern to reduce CVD risk’. It also highlights the Mediterranean diet as one of the most evidence-based dietary patterns beneficial for CVD prevention.

Dietary protein intake in midlife in relation to healthy aging – results from the prospective Nurses’ Health Study cohort. (Ardisson Korat et al, 2024).
The findings from this large, prospective study, involving 48,762 female nurses, suggest that long-term dietary protein intake, and especially plant protein, may be related to higher odds of healthy aging. Among the findings, plant protein was associated with higher odds of the absence of physical function limitations, and good mental status. Substitution analyses found significant positive associations for the isocaloric replacement of animal or dairy protein, carbohydrate, or fat with plant protein.