The body of evidence about nuts and health continues to grow. These local and international papers, outlining new nut research published around August 2021, corroborate decades of research about the importance of a regular handful of nuts in a healthy diet.

Small targeted dietary changes can yield substantial gains for human and environmental health. (2021)
US-based researchers evaluated 5,853 foods to identify environmentally sustainable foods that promote health. They quantified whether the foods either added or took minutes away from a ‘healthy life’. Results suggested that substituting just 10% of daily calorie intake from beef or processed meat in favour of fruit, vegetables, nuts, legumes and ‘selected seafood’ adds 48 minutes of healthy life every day and cuts our carbon footprint by a third (33%). Eating a 30g serve of nuts and seeds provides a gain of 25 minutes of healthy life per day.

Nut consumption, body weight, and adiposity in patients with type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials. (2021)
The review paper, which collated the outcomes of 15 randomised controlled trials involving 899 people, found nut consumption has no effect, positive or negative, on body weight in people with type 2 diabetes. It also found no significant effects of nut-enriched interventions on body mass index, waist circumference or percent body fat. It backs up previous research that nut consumption does not lead to weight gain in the general population.

Association of walnut consumption with total and cause-specific mortality and life expectancy in US adults. (2021)
This research reports on the outcomes of large prospective cohort studies, which followed more than 67,000 US-based women and 26,000 men for up to 20 years. The outcomes were positive for walnuts, linking consumption (and particularly higher consumption, of ≥5 serves/week), with a lower risk of total and cardiovascular disease mortality, and a greater gained life expectancy, compared with those who didn’t consume walnuts.

Pecan-enriched diets alter cholesterol profiles and triglycerides in adults at risk for cardiovascular disease in a randomized, controlled trial. (2021)
In this randomised controlled trial, 56 adults at-risk for cardiovascular disease (CVD) were allocated to either a control group, or one of two pecan groups: an ADD group, which added 68g of pecans to their regular diet, and a SUB group, that substituted the pecans (68g) for isocaloric foods from their diet. After 8 weeks, total cholesterol (TC), LDL cholesterol, triglycerides, TC/HDL cholesterol ratio, non–HDL cholesterol and apolipoprotein B were reduced in both pecan groups, with no changes in the control group.

Prevalence and early-life risk factors for tree nut sensitization and allergy in young adults. (2021)
This population-based cohort study (the Swedish birth cohort BAMSE) gauged the prevalence of tree nut sensitisation and reported symptoms at age 24 years, and also assessed early-life factors linked with the development of tree nut allergy. In this Swedish cohort, prevalence of tree nut sensitisation was found to be common (21.2%), but usually asymptomatic. Egg allergy, eczema and asthma at pre-school age were linked with future development of tree nut symptoms and storage protein sensitization.

Adherence to the Mediterranean diet, five-year weight change, and risk of overweight and obesity: A systematic review and dose–response meta-analysis of prospective cohort studies. (2021)
This research combined the outcomes of six prospective cohorts, together involving more than 244,000 adults. It revealed that greater adherence to the Mediterranean diet was associated with a 9% decreased risk of overweight and/or obesity. It also found less weight gain over five years in those adhering to a Mediterranean dietary pattern. In conclusion, the researchers suggest their findings have practical importance for public health.

Plant‐centered diet and risk of incident cardiovascular disease during young to middle adulthood. (2021)
This prospective study concluded that consumption of a plant‐centred, high‐quality diet (or shifting to such a diet) starting in young adulthood is associated with a lower cardiovascular disease (CVD) risk by middle age. It followed 4,946 adults, who were 18 to 30 years old at baseline and free of CVD, for more than 30 years. Higher consumption of nutritionally-rich plant foods and limited consumption of high‐fat meat products and less healthy plant foods were associated with a lower risk of CVD.

The relationship between adherence to the Mediterranean diet, intake of specific foods and depression in an adult population (45–75 Years) in primary health care. A cross-sectional descriptive study. (2021)
This study looked at the link between adherence to the Mediterranean diet, and the intake of specific foods, in people aged 45 to 75 with depression. It found being female, younger, with a higher BMI, consuming more than 1 serving of red meat a day and drinking >1 carbonated or sugary drink daily, not consuming 3 servings of nuts a week and not eating 2 vegetables cooked in olive oil a week to be predictors of having higher depressive symptoms. The study authors point out that the relationship between nutrition and depression must be further examined.