The body of evidence about nuts and health continues to grow. These local and international papers, outlining new nut research, corroborate decades of research about the importance of a regular handful of nuts in a healthy diet.

Association of major dietary protein sources with all‐cause and cause‐specific mortality: Prospective cohort study. (2021).

This prospective cohort study followed more than 102,000 post-menopausal women (aged 50 to 79 years old at the start of the study) for an average of 18 years. The women were enrolled in the well-regarded Women’s Health Initiative. It found eating more plant protein, and substituting animal protein with plant protein, was linked with a lower risk of all-cause mortality, cardiovascular disease (CVD) and dementia. Among the key findings was that substituting total red meat, eggs and dairy products with nuts was associated with a lower risk of death from all causes.

Total nut, tree nut, and peanut consumption and metabolic status in southern Italian adults. (2021).

This study looked at associations between nut consumption and hypertension, type 2 diabetes and dyslipidaemia in 2,044 Southern Italian adults. The average (mean) intake of nuts in the ‘high nut intake’ group was about 40g/day, while for those in the ‘low nut intake’ group, it was around 4g/day. It found higher nut intake was inversely linked with hypertension (in particular) and also type 2 diabetes. After adjusting for numerous factors, including energy intake and a Mediterranean dietary pattern, higher nut intake was linked with a 56% decrease in the odds of having hypertension. And high nut consumers had nearly double the polyphenol intake of people with a low intake.

Socioeconomic and lifestyle factors modifies the association between nut consumption and metabolic syndrome incidence. (2021).

This prospective cohort study found an association between consuming nuts and a reduced risk of metabolic syndrome (MetS), particularly among more physically active study participants. The researchers tracked 1,915 adults, who were part of the Tehran Lipid and Glucose study, for around nine years. Consuming nuts higher than the median and having moderate to high physical activity levels resulted a 26% and 37% reduction in Mets, respectively. Participants who did not smoke had lower risk of MetS, regardless of the amount of nuts they consumed. And the risk reduction with nuts was seen in both educated and non-educated groups. 

Has the prevalence of peanut allergy changed following earlier introduction of peanut? The EarlyNuts Study. (2021).

The Australian-based EarlyNuts study found that peanut allergy has fallen in Australia since children have been introduced to peanuts earlier in life. It notes that Australian infant feeding guidelines changed in 2016 to recommend starting children on peanuts and other allergenic foods earlier (by age 12 months). The research suggests parents have embraced this advice, and the earlier introduction of peanuts has led to a 16% decrease in peanut allergy. Despite this promising data, the researchers note the overall prevalence of peanut allergy is still high.

Whole almond consumption is associated with better diet quality and cardiovascular disease risk factors in the UK adult population: National Diet and Nutrition Survey (NDNS) 2008–2017. (2021).

This research, a secondary analysis of the UK’s National Diet and Nutrition Survey 2008–2017, estimated whole almond consumption among the UK population, and looked at how this impacted diet quality. Around 7.6% of the population were eating almonds, with a median intake of 5g/day. Almond consumption was linked with better dietary quality scores and lower cardiovascular disease risk factors. BMI and waist circumference were lower in whole almond consumers, compared to non-consumers. UK almond consumers also had overall healthier dietary patterns.

The carbon footprint of dietary guidelines around the world: A seven country modelling study. (2021).

This study looked at the greenhouse gas emissions associated with the national dietary guidelines of seven countries (Germany, India, the Netherlands, Oman, Thailand, Uruguay, and the United States). Overall, US recommendations had the highest carbon footprint. This was more than twice that of plant-forward recommendations, like that of EAT-Lancet, the US Vegetarian guidelines, or India’s guidelines – the country with the smallest footprint. A key difference was the amount and type of protein recommended. The authors hope their findings will inform decision-making, to incorporate environmental sustainability, in future dietary guidance.

Plant foods, dietary fibre and risk of ischaemic heart disease in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. (2021).

This large prospective cohort study examined links between major plant foods, their subtypes and dietary fibre, and risk of ischemic heart disease (IHD). It followed more than 490,000 European-based adults, without a prior history of myocardial infarction or stroke, for more than 12 years. Higher intakes of fruit and vegetables (combined), total fruit, bananas, nuts and seeds, total fibre, fruit and vegetable combined fibre, and fruit fibre were associated with a lower risk of IHD, of small magnitude. No associations were found for vegetables, legumes, cereals and IHD risk. The findings support overall recommendations to increase intake of plant-based foods.

Effects of cashew nut consumption on body composition and glycemic indices: A meta-analysis and systematic review of randomized controlled trials. (2021).

Incorporating cashews into the diet has no significant effect on body weight or glycemic indices (fasting blood sugar, and HOMA-IR, a measure of insulin resistance), according to this study. It looked at the combined outcomes of six clinical trials, involving 521 people. Combined effect sizes revealed no effect of cashew consumption on weight, BMI and waist circumference. The findings are consistent with other research, and using different nut types, which shows nut consumption is not linked with weight gain.