Snacking frequency has increased in recent years, with many snack options being nutrient-poor and likely contributing to excessive energy intakes (1,2). At the same time, nut intakes have remained low(3). While almonds, like many other snacks, are high in fat and energy, they are rich in beneficial unsaturated fats, fibre, vitamins, minerals, and phytonutrients. Snacking on almonds may offer substantial health advantages, including improving energy balance and overall diet quality, compared to typical modern snack foods. The healthier diets observed among nut consumers may be partially explained by addition of nuts to the diet leading to displacement of other, less desirable foods. We aimed to compare the effects of consuming a snack of almonds vs sweet biscuits or savoury crackers daily for one year on displacement of discretionary foods and food group patterns. We used a randomised controlled parallel study design involving 136 non-obese habitual discretionary snack consumers aged 18–65. Participants were randomly assigned to receive a snack of either almonds, or biscuits, daily for one year. These isocaloric snacks provided either 10% of participants’ total energy requirements or 1030 kJ (equivalent to 42.5 g almonds), whichever was higher. Dietary intake was measured using three-day weighed diet records record at baseline, 3, 6, and 12 months. Of the participants, 101 (74%) were female, with a mean (SD) age of 35.6 (13.4) years and BMI of 23.7 (3.0) kg/m2. Those assigned to the almond group increased their percentage total energy (%TE) from nuts and seeds from 1.4% (baseline) to 13.8% (12 months), while those assigned to the biscuit group increased %TE from biscuits and crackers from 5.1% to 12.4%. There was a non-statistically significant (p = 0.053) decrease in %TE from discretionary foods to 12-months for almond group compared to the biscuit group. %TE from discretionary foods decreased significantly in the almond group from baseline to 12-months (mean (95% CI) difference: −4.9% (−8.3, −1.5) p = 0.005), with no evidence of a change observed in the biscuit group (−0.0% (−3.6, 3.6) p = 0.994). Regular consumption of nuts as a snack food may improve diet quality by displacing discretionary food intake among regular discretionary snack consumers. However, the observed displacement was incomplete relative to the energy provided by the study snack. Snacking is driven by factors beyond simply satisfying hunger, including flavour, texture, and overall eating experience. We hypothesise that – among this group of discretionary snack consumers – partial displacement, and hence the continued consumption of other snack foods, was likely due to the sensory properties of consuming almonds alone being insufficient to fulfil hedonic satiation. Strategies to improve sensory appeal of almonds to discretionary snack consumers may assuage subsequent snack-seeking behaviour and provide important advantages in terms of both energy balance and diet quality.

Including nuts in the diet has been associated with improvements in cardiovascular disease (CVD) risk factors including high blood pressure (BP) and hyperlipidaemia (1–2). However, few studies have investigated if the same benefits exist for medicated and unmedicated populations. This systematic review and meta-analysis investigated the effects of nut intake on BP and lipids, with a sub-analysis evaluating response differences according to BP and lipid-lowering medication usage. MEDLINE, EMBASE, Scopus and Web of Sciences databases were searched for randomised controlled trials (RCTs) of longer than 3 weeks duration that assessed the effects of whole tree nuts or peanuts on BP and lipid responses. The American Diabetes Association Quality Criteria checklist was used to assess the risk of bias, and studies with a negative rating were removed from the meta-analysis. A random-effects meta-analysis was conducted, with subgroup analyses performed based on medication use (medicated, unmedicated, unreported, and mixed-use). Inter-study heterogeneity was estimated using the I2 test statistic. Data from 107 articles describing 98 studies (61 parallel, and 37 cross-over designs) were included in the meta-analysis. Overall, significant benefits of nut consumption were observed for triglycerides (TG) (mean difference [MD]: −0.11 mmol/L, 95% confidence intervals [CI]: −0.16, −0.06, p < 0.01, I2: 32.95%), total cholesterol (TC) (MD: −0.15 mmol/L, 95% CI: −0.22, −0.08, p < 0.01, I2: 61.84%), and low-density lipoprotein cholesterol (LDL-C) (MD: −0.12 mmol/L, 95% CI: −0.19, −0.06, p < 0.01, I2: 52.7%), but not high-density lipoprotein cholesterol, systolic BP, or diastolic BP. Among unmedicated populations, nut intake resulted in a significant decrease in TG (MD: −0.16 mmol/L, 95% CI: −0.30, −0.03, I2: 75.93%), and TC (MD: −0.21 mmol/L, 95% CI: −0.39, −0.03, I2: 86.59%), while in those with unreported medication use, there were significant decreases in TG (MD: −0.08 mmol/L, 95% CI: −0.15, −0.01, I2: 0%), TC (MD: −0.15 mmol/L, 95% CI: −0.22, −0.07, I2: 0%) and LDL-C (MD: −0.12 mmol/L, 95% CI: −0.19, −0.06, I2: 0.44%). No significant effects were observed for BP and lipids in the mixed medication group. While there were significant improvements in lipid profiles overall with tree nuts and peanuts consumption, we observed no benefits for BP. Furthermore, significant beneficial effects on lipids were only observed in those with unreported and no medication use. Few studies investigated effects in medicated participants only (n = 1 study for lipids), and the precise proportion of medication use within the mixed medicated group remains unclear. Consequently, it remains uncertain whether the lipid-lowering properties of consuming nuts remain when hyperlipidaemia is managed with medications. Further studies are needed to explore the influence of medication in combination with dietary approaches on responses to additional CVD risk factors.

Energy-restricted (ER) diets promote weight loss and improve body composition and glycaemic control. Nut consumption also improves these parameters. However, less is known about the combined benefit of these two strategies. This scoping review implemented a systematic search of Medline, Embase and Scopus to identify randomised controlled trials evaluating the effect of ER diets with or without nuts on body mass, body composition and glycaemic control in adults. After reviewing titles and abstracts, twenty-nine full-text articles were screened, resulting in seven studies reported in eight papers that met the inclusion criteria. Energy restriction was achieved by prescribing a set energy target or reducing intake by 1000–4200 kJ from daily energy requirements. Interventions ranged from 4 to 52 weeks in duration and contained 42–84 g/d of almonds, peanuts, pistachios or walnuts. While all studies reported that energy restriction resulted in significant weight loss, the addition of nuts to ER diets demonstrated significantly greater weight loss in only approximately half of the included studies (4/7 studies). There was limited evidence to support additional benefits from nuts for body composition measures or glycaemic control. Although improvements in weight loss and glycaemia were not consistent when nuts were included in ER diets, no study revealed an adverse effect of nut consumption on health outcomes. Future studies could explore the effect of consuming different types and amounts of nuts, combined with various levels of energy restriction on weight, body composition and glycaemic control.

Nuts are an important component of a healthy diet, but little has been known about their effects on muscle health. Therefore, this study examined the association between nut consumption and low muscle strength among Korean adults. This cross-sectional analysis was conducted using single 24-h recall and handgrip strength data from 3962 younger adults 19–39 years, 6921 middle-aged adults 40–64 years and 3961 older adults ≥65 years participated in the seventh cycle (2016–2018) of the Korea National Health and Nutrition Examination Survey. Low muscle strength was defined as handgrip strength <28 kg for men and <18 kg for women. Sex-specific OR were obtained for younger, middle-aged and older adults using multivariable logistic regression analyses. About one in four Korean adults were consuming nuts (using a culinary definition) with peanut being the most frequently consumed type. After adjustment for age, BMI, total energy intake, household income, alcohol consumption, smoking, resistance exercise, medical history and dietary protein intake, nut consumption was associated with the lower risk of low muscle strength among older adults ≥65 years (men: OR 0·55, 95 % CI (0·38, 0·79); women: OR 0·69, 95 % CI (0·51, 0·93)); however, this association was not observed among younger adults 19–39 years or middle-aged adults 40–64 years. Our results suggest that consuming nuts might be beneficial in lowering the risk of low muscle strength among Korean older adults.

Numerous epidemiological studies have suggested that nut intake is associated with a reduced risk of mortality. Although diets and lifestyles differ by regions or races/ethnicities, few studies have investigated the associations among non-white, non-Western populations. We evaluated the associations of total nut and peanut intakes with all-cause and cause-specific mortality in a population-based prospective cohort in Japan. Participants (age: ≥35 years at baseline in 1992; n 31 552) were followed up until death or the end of follow-up in 2008. Those with cancer, CHD or stroke at baseline were excluded. Dietary intake was assessed only at baseline by using a validated FFQ. In total, 2901 men died during 183 299 person-years and 2438 women died during 227 054 person-years. The mean intakes of total nuts were 1·8 and 1·4 g/d in men and women, respectively. Although peanut intake accounted for approximately 80 % of the total nut intake, total nut and peanut intakes were inversely associated with all-cause mortality in men after adjusting for all potential confounders. For example, compared with the lowest quartile category, the adjusted hazard ratio (95 % CI) of total nut intake for all-cause mortality in men of the highest quartile category was 0·85 (95 % CI 0·75, 0·96) (Pfor trend = 0·034). Peanut intake was inversely associated with digestive disease mortality in men and CVD mortality in women. Total nut and peanut intakes, even in low amounts, were associated with a reduced risk of mortality particularly in men.

The consumption of nuts and extra-virgin olive oil has been associated with suppression of inflammatory pathways that contribute to atherosclerosis, but its role on the modulation of the inflammatory profile in patients with established coronary artery disease (CAD) is unclear. The aim of this study was to evaluate the effects of adding pecan nuts or extra-virgin olive oil to a healthy diet on inflammatory markers in patients with stable CAD. In this randomised clinical trial, 204 patients were enrolled to three study groups: sixty seven to control group (CG: healthy diet), sixty eight to pecan nuts group (PNG: 30 g/d of pecans + healthy diet) and sixty nine to extra-virgin olive oil group (OOG: 30 ml/d of extra-virgin olive oil + healthy diet). High-sensitivity C-reactive protein (hs-CRP, in mg/l), fibrinogen (mg/dl), IL 2, 4, 6, 10 (pg/ml) and interferon-γ (IFN-γ, in pg/ml), IL-6/IL-10, IL-2/IL-4 and IFN-/γIL-4 ratios were evaluated at baseline and after the follow-up (12 weeks). As main results, after adjustment for sex, statin used and relative body weight variation, there were no differences between groups regarding inflammatory markers at the end of the study. IL-6 levels (primary outcome) were reduced in 12 weeks when compared with baseline in all study groups (CG: difference: −0·593 (se = 0·159) pg/dL; PNG: difference: −0·335 (se = 0·143) pg/dl; OOG: IL-6 difference: −0·325 (se = 0·143) pg/dl). In conclusion, there was no significant effect of including pecan nuts or extra virgin olive oil to a healthy diet on inflammatory markers in individuals with CAD.

Nut-based products may aid low-glycaemic dietary strategies that are important for diabetes prevention in populations at increased risk of dysglycaemia, such as Asian Chinese. This randomised cross-over trial assessed the postprandial glycaemic response (0–120 min) of a higher-protein nut-based (HP-NB) snack formulation, in bar format (1009 kJ, Nutrient Profiling Score, NPS, −2), when compared with an iso-energetic higher-carbohydrate (CHO) cereal-based bar (HC-CB, 985 kJ, NPS +3). It also assessed the ability to suppress glucose response to a typical CHO-rich food (white bread, WB), when co-ingested. Ten overweight prediabetic Chinese adults (mean, sd: age 47⋅9, 15⋅7 years; BMI 25⋅5, 1⋅6 kg/m2), with total body fat plus ectopic pancreas and liver fat quantified using dual-energy X-ray absorptiometry and magnetic resonance imaging and spectroscopy, received the five meal treatments in random order: HP-NB, HC-CB, HP-NB + WB (50 g available CHO), HC-CB + WB and WB only. Compared with HC-CB, HP-NB induced a significantly lower 30–120 min glucose response (P < 0⋅05), with an approximately 10-fold lower incremental area under the glucose curve (iAUC0–120; P < 0⋅001). HP-NB also attenuated glucose response by approximately 25 % when co-ingested with WB (P < 0⋅05). Half of the cohort had elevated pancreas and/or liver fat, with 13–21 % greater suppression of iAUC0–120 glucose in the low v. high organ fat subgroups across all five treatments. A nut-based snack product may be a healthier alternative to an energy equivalent cereal-based product with evidence of both a lower postprandial glycaemic response and modulation of CHO-induced hyperglycaemia even in high-risk, overweight, pre-diabetic adults.

There is increasing evidence linking the gut microbiota to various aspects of human health. Nuts are a food rich in prebiotic fibre and polyphenols, food components which have been shown to have beneficial effects on the gut microbiota. This systematic review aimed to synthesise the evidence regarding the effect of nut consumption on the human gut microbiota. A systematic search of the databases MEDLINE, PubMed, Cochrane CENTRAL and CINAHL was performed until 28 November 2019. Eligible studies were those that investigated the effects of nut consumption in humans (aged over 3 years old), utilising next-generation sequencing technology. Primary outcome measures were between-group differences in α- and β-diversity metrics and gut microbial composition. A total of eight studies were included in the review. Included studies assessed the effects of either almonds, walnuts, hazelnuts or pistachios on the gut microbiota. Overall, nut consumption had a modest impact on gut microbiota diversity, with two studies reporting a significant shift in α-diversity and four reporting a significant shift in β-diversity. Walnuts, in particular, appeared to more frequently explain shifts in β-diversity, which may be a result of their unique nutritional composition. Some shifts in bacterial composition (including an increase in genera capable of producing SCFA: Clostridium, Roseburia, Lachnospira and Dialister) were reported following the consumption of nuts. Nut intake may yield a modulatory effect on the gut microbiota; however, results were inconsistent across studies, which may be explained by variations in trial design, methodological limitations and inter-individual microbiota.

Type 2 diabetes mellitus is a chronic disease increasing in global prevalence. Although habitual consumption of walnuts is associated with reduced risk of CVD, there is inconsistent evidence for the impact of walnut consumption on markers of glycaemic control. This systematic review and meta-analysis aimed to examine the effect of walnut consumption on markers of blood glucose control. A systematic search of Medline, PubMed, CINAHL and Cochrane databases (to 2 March 2019) was conducted. Inclusion criteria were randomised controlled trials conducted with adults which assessed the effect of walnut consumption on fasting blood glucose and insulin, glycated Hb and homeostatic model assessment of insulin resistance. Random effects meta-analyses were conducted to assess the weighted mean differences (WMD) for each outcome. Risk of bias in studies was assessed using the Cochrane Risk of Bias tool 2.0. Sixteen studies providing eighteen effect sizes were included in the review. Consumption of walnuts did not result in significant changes in fasting blood glucose levels (WMD: 0·331 mg/dl; 95 % CI −0·817, 1·479) or other outcome measures. Studies were determined to have either ‘some concerns’ or be at ‘high risk’ of bias. There was no evidence of an effect of walnut consumption on markers of blood glucose control. These findings suggest that the known favourable effects of walnut intake on CVD are not mediated via improvements in glycaemic control. Given the high risk of bias observed in the current evidence base, there is a need for further high-quality randomised controlled trials.

The bioaccessibility of fat has implications for satiety and postprandial lipidaemia. The prevailing view holds that the integrity of plant cell wall structure is the primary determinant of energy and nutrient extraction from plant cells as they pass through the gastrointestinal (GI) tract. However, comparisons across nuts (walnuts, almonds and pistachios) with varying physical properties do not support this view. In the present study, masticated samples of three nuts from healthy adults were exposed to a static model of gastric digestion followed by simulated intestinal digestion. Primary outcomes were particle size and lipid release at each phase of digestion. Walnuts produced a significantly larger particle size post-mastication compared with almonds. Under gastric and intestinal conditions, the particle size was larger for walnuts compared with pistachios and almonds (P < 0·05). However, the masticated and digesta particle sizes were not related to the integrity of cell walls or lipid release. The total lipid release was comparable between nuts after the in vitro intestinal phase (P > 0·05). Microstructural examination showed ruptured and fissured cell walls that would allow digestion of cellular contents, and this may be governed by internal cellular properties such as oil body state. Furthermore, the cell walls of walnuts tend to rupture rather than separate and as walnut tissue passes through the GI tract, lipids tend to coalesce reducing digestion efficiency.

The primary aim was to investigate the effects of nut and seed consumption on markers of glucose metabolism in adults with prediabetes. Studies with a randomised controlled trial (RCT) design, comparing the effects of a diet containing nuts or seeds against a diet without nuts or seeds in adults with prediabetes, were considered eligible. Primary outcome measures included fasting plasma glucose (FPG), 2-h plasma glucose during oral glucose tolerance test and glycated Hb (HbA1c) concentrations. Studies were identified by searching PubMed and Scopus electronic databases and by checking full texts and reference lists of relevant records. Risk of bias was assessed using the Cochrane Collaboration’s tool. We included five RCT involving 371 adults with prediabetes or at risk of diabetes; three RCT investigated the effects of whole nut consumption and two the effects of ground flaxseed consumption. Consumption of 57 g/d pistachios or mean intake of 60 g/d almonds for 4 months improved FPG and fasting plasma insulin (FPI) concentrations, insulin resistance, cellular glucose uptake in lymphocytes and β-cell function. Consumption of 56 g/d walnuts for 6 months was not found to affect FPG or HbA1c concentrations. Consumption of 13 g/d flaxseed for 3 months improved FPG and FPI concentrations and insulin resistance. In a second study, however, flaxseed consumption was not found to affect markers of glucose metabolism. The risk of bias was generally low, thus the reported results could be reliable. Further investigation of nut and seed consumption effects in the field of prediabetes is warranted.

Older adults tend to require fewer energy content and higher levels of nutrients to promote and maintain optimal health. Regrettably, dietary variety and quality are known to decline with advancing age. We conducted a 2-year prospective, randomised, dietary intervention trial where we asked free-living elderly subjects (63–79 years) on self-selected habitual diets to incorporate walnuts daily into their diet (15 % energy). We then compared their nutrient intake with that of a similar group of concurrent participants on self-selected habitual diets but abstaining from walnut consumption (control). No recipes or advice on use of nuts were provided. Dietary intake was assessed by multiple unannounced 24-h telephone dietary recalls. On average, walnut supplement consumption was 43 g/d or 1171·5 kJ (281 kcal). The mean daily energy intake was 954 kJ (228 kcal) higher in the walnut group than in the control group (P<0·001). Compared with control, participants in the walnut group reported significantly higher intake of total protein, vegetable protein, total PUFA and n-3 and n-6 PUFA; and significantly lower intake of total carbohydrate, animal protein, SFA, and Na. An estimated 19 % of total energy and 25 % of total fat from other food sources was displaced. Displacement of MUFA and total PUFA was 21 and 16 %, respectively. Thus adding a daily supplement of walnuts to an ad libitum diet of older adults can induce favourable modifications to the nutrient profile in a way that addresses declining nutrient intake associated with aging.

The post-lunch dip in cognition is a well-established phenomenon of decreased alertness, memory and vigilance after lunch consumption. Lunch composition reportedly influences the post-lunch dip. Moreover, dieting is associated with cognitive function impairments. The negative effects of dieting have been reversed with nut-supplemented diets. The aims of this study were to (1) evaluate the acute effect of an almond-enriched high-fat lunch or high-carbohydrate lunch on the post-lunch decline in cognitive function, and (2) evaluate the effects of chronic almond consumption as part of an energy-restricted diet on the memory and attention domains of cognitive function. In total, eighty-six overweight and obese adults were randomised to consume either an almond-enriched diet (AED) or a nut-free control diet (NFD) over a 12-week weight loss intervention. Participants were also randomised to receive either an almond-enriched high-fat lunch (A-HFL) (>55 % energy from fat, almonds contributing 70–75 % energy) or a high-carbohydrate lunch (HCL) (>85 % energy from carbohydrates) at the beginning and end of the weight loss intervention. Memory and attention performance indices decreased after lunch consumption (P<0·001). The A-HFL group ameliorated the decline in memory scores by 57·7 % compared with the HCL group (P=0·004). Both lunch groups had similar declines in attention. Moreover, memory and attention performance indices increased after the 12-week intervention period (P<0·05) with no difference between the AED and NFD groups. In conclusion, almond consumption at a midday meal can reduce the post-lunch dip in memory. However, long-term almond consumption may not further improve cognitive function outcomes in a weight loss intervention.

Dietary patterns containing nuts are associated with a lower risk of CVD mortality, and increased nut consumption has been shown to have beneficial effects on CVD risk factors including serum lipid levels. Recent studies have reported on the relationship between nut intake and CVD outcomes and mortality. Our objective was to systematically review the literature and quantify associations between nut consumption and CVD outcomes and all-cause mortality. Five electronic databases (through July 2015), previous reviews and bibliographies of qualifying articles were searched. In the twenty included prospective cohort studies (n 467 389), nut consumption was significantly associated with a lower risk of all-cause mortality (ten studies; risk ratio (RR) 0·81; 95 % CI 0·77, 0·85 for highest v. lowest quantile of intake, Phet=0·04, I2=43 %), CVD mortality (five studies; RR 0·73; 95 % CI 0·68, 0·78; Phet=0·31, I2=16 %), all CHD (three studies; RR 0·66; 95 % CI 0·48, 0·91; Phet=0·0002, I2=88 %) and CHD mortality (seven studies; RR 0·70; 95 % CI 0·64, 0·76; Phet=0·65, I2=0 %), as well as a statistically non-significant reduction in the risk of non-fatal CHD (three studies; RR 0·71; 95 % CI 0·49, 1·03; Phet=0·03, I2=72 %) and stroke mortality (three studies; RR 0·83; 95 % CI 0·69, 1·00; Phet=0·54, I2=0 %). No evidence of association was found for total stroke (two studies; RR 1·05; 95 % CI 0·69, 1·61; Phet=0·04, I2=77 %). Data on total CVD and sudden cardiac death were available from one cohort study, and they were significantly inversely associated with nut consumption. In conclusion, we found that higher nut consumption is associated with a lower risk of all-cause mortality, total CVD, CVD mortality, total CHD, CHD mortality and sudden cardiac death.

Nut intake has been associated with reduced inflammatory status and lower risk of CVD and mortality. The aim of this study was to examine the relationship between nut consumption and mortality and the role of inflammation. We conducted a population-based prospective investigation on 19 386 subjects enrolled in the Moli-sani study. Food intake was recorded by the Italian version of the European Project Investigation into Cancer and Nutrition FFQ. C-reactive protein, leucocyte and platelet counts and the neutrophil:lymphocyte ratio were used as biomarkers of low-grade inflammation. Hazard ratios (HR) were calculated using multivariable Cox proportional hazard models. During a median follow-up of 4·3 years, 334 all-cause deaths occurred. As compared with subjects who never ate nuts, rare intake (≤2 times/month) was inversely associated with mortality (multivariable HR=0·68; 95 % CI 0·54, 0·87). At intake ≥8 times/month, a greater protection was observed (HR=0·53; 0·32, 0·90). Nut intake (v. no intake) conveyed a higher protection to individuals poorly adhering to the Mediterranean diet (MD). A significant reduction in cancer deaths (HR=0·64; 95 % CI 0·44, 0·94) was also observed, whereas the impact on CVD deaths was limited to an inverse, but not significant, trend. Biomarkers of low-grade inflammation were reduced in nut consumers but did not account for the association with mortality. In conclusion, nut intake was associated with reduced cancer and total mortality. The protection was stronger in individuals with lower adherence to MD, whereas it was similar in high-risk groups (diabetics, obese, smokers or those with the metabolic syndrome), as compared with low-risk subjects. Inflammation did not explain the observed relationship.

It is unclear whether lifestyle modifications, such as dietary changes, should be advocated to prevent olfactory dysfunction. We investigated the association between dietary intakes of fats (saturated, mono-unsaturated and polyunsaturated fats, and cholesterol) and related food groups (nuts, fish, butter, margarine) with olfactory impairment. There were 1331 and 667 participants (older than 60 years) at baseline and 5-year follow-up, respectively, with complete olfaction and dietary data. Dietary data were collected using a validated semi-quantitative FFQ. Olfaction was measured using the San Diego Odor Identification Test. In a cross-sectional analysis of baseline data, those in the highest v. lowest quartile of n-6 PUFA intake had reduced odds of having any olfactory impairment, multivariable-adjusted OR 0·66 (95 % CI 0·44, 0·97), P for trend = 0·06. Participants in the highest v. lowest quartile of margarine consumption had a 65 % reduced odds of having moderate/severe olfactory impairment (P for trend = 0·02). Participants in the highest quartile compared to the lowest quartile (reference) of nut consumption had a 46 % (P for trend = 0·01) and 58 % (P for trend = 0·001) reduced odds of having any or mild olfactory impairment, respectively. Older adults in the highest v. lowest quartile of fish consumption had 35 % (P for trend = 0·03) and 50 % (P for trend = 0·01) reduced likelihood of having any or mild olfactory impairment, respectively. In longitudinal analyses, a marginally significant association was observed between nut consumption and incidence of any olfactory impairment, highest v. lowest quartile of nut consumption: OR 0·61 (95 % CI 0·37, 1·00). Older adults with the highest consumption of nuts and fish had reduced odds of olfactory impairment, independent of potential confounding variables.