The body of evidence about nuts and health continues to grow. These local and international research papers, published around January 2023, corroborate decades of research about the importance of a regular handful of nuts within a healthy diet.

The effects of tree nut and peanut consumption on energy compensation and energy expenditure: A systematic review and meta-analysis. (2022).
This systematic review examined the effect of tree nut and peanut consumption on energy intake, compensation, and expenditure. Among the findings, energy compensation occurred after nut-containing loads (range: −280.5% to +176.4%) – suggesting this as a potential mechanism for a lack of association between nut consumption and body weight. The degree of compensation varied depending on the form (whole or chopped) and how the nuts were consumed (alone or within a meal). No evidence was found for energy expenditure as an energy-regulating mechanism of nuts.

Long-term consumption of nuts (including peanuts, peanut butter, walnuts, and other nuts) in relation to the risk of frailty in older women: Evidence from a cohort study. (2023).
This large US-based prospective cohort study looked at the link between nut consumption and frailty in an aging female population (71,704 non-frail women, ≥60 years old). Frailty was defined as having ≥3 of the FRAIL components (fatigue, lower strength, reduced aerobic capacity, multiple chronic conditions, significant weight loss), and was assessed every four years, from 1992 to 2016. It found a strong and consistent inverse association between regular nut consumption and incident frailty. Consuming ≥5 serves/wk of nuts was linked with a 20% lower risk of frailty, compared to <1 serving/month.

Almond intake alters the acute plasma dihydroxy-octadecenoic acid (DiHOME) response to eccentric exercise. (2023).
This study, involving 64 adults, investigated whether eating almonds can mitigate post-exercise inflammation, and muscle soreness and damage. Using a parallel group design, participants were randomised to almond (57g/day) or cereal bar (kilojoule matched) treatment groups for a 4-week period, prior to undertaking 90 minutes of exercise. It found some positive effects of almond intake, compared to the cereal bar. This included reduced feelings of fatigue and tension, better leg-back strength during recovery, and decreased muscle damage during the first day of recovery.

Adding walnuts to the usual diet can improve diet quality in the United States: Diet modelling study based on NHANES 2015–2018. (2023).
This modelling study looked at the impact, on diet quality and nutrients of concern, of adding 28g of walnuts to the usual diets of 7,757 ‘no-nut’ US-based consumers aged ≥4 years. It found that Healthy Eating Index scores, measuring diet quality, improved significantly in both children and adults. And adding walnuts resulted in significant reductions in the percentages of adults with intakes below the EAR for magnesium and folate (69.6% vs. 52.0%; 49.2% vs. 40.6%, respectively), and increased the percentage of adults above the AI for potassium (22.8% vs. 26.5%). A similar trend was seen for children.

The effect of daily peanut consumption on cognitive function and indicators of mental health among healthy young women. (2022).
This study, involving 65 participants, looked at the effect of consuming 49g/day of peanuts for 12 weeks on cognitive function and mental health, compared to consuming a peanut-free diet, among healthy young women. Peanut consumption did not appear to increase scores on a cognitive function assessment, compared with usual diet consumption. And there was no effect of peanut consumption on depression, anxiety, or stress scores. However, peanut consumption did significantly increase processing speed time, from baseline to endline.

The beneficial effects of pine nuts and its major fatty acid, pinolenic acid, on inflammation and metabolic perturbations in inflammatory disorders. (2023).
This review centers on a less-studied fatty acid – pinolenic acid (PNLA) from pine nuts, which typically comprises up to 20% of its total fatty acids. PNLA is emerging as a dietary PUFA. The focus of the review is on the potential actions of PNLA on inflammation, along with modulation of lipid metabolism and oxidative stress, based on data from both in vitro and in vivo experiments, and human findings, including gene expression analysis. 

Long-term consumption of ten food groups and cardiovascular mortality: A systematic review and dose response meta-analysis of prospective cohort studies. (2022).
This review, of 22 studies with a total of 70,273 participants, assessed the relationship between long-term consumption of 10 food groups and cardiovascular mortality. Among the findings, a long-term high intake of fruits and vegetables, nuts, and whole grains were significantly linked with a 28%, 27% and 13% (respectively) lower risk of cardiovascular mortality, compared to the lowest intake of each. The researchers noted that more data on the long-term effects of legumes on cardiovascular mortality is needed.

Plant-based diets and lipid, lipoprotein, and inflammatory biomarkers of cardiovascular disease: A review of observational and interventional studies. (2022).
This literature review looked at the impact of plant-based diets (PBDs) on cardiovascular disease (CVD) biomarkers. It concluded that the available randomised controlled trial and prospective cohort evidence shows favourable relationships between PBDs and lipid and lipoprotein profiles (decreased total cholesterol, LDL-cholesterol, and apolipoprotein B), and less low-grade inflammation (decreased C-reactive protein). Specific to nuts, the authors say: ‘Nuts are a plant food group consistently associated with reduced risk of CVD outcomes’.