Nutritional therapy should follow evidence-based practice, thus several societies regarding nutrition and critical care have developed specific Clinical Practice Guidelines (CPG). However, to be regarded as trustworthy, the quality of the CPG for critically ill patients and its recommendations need to be high. This systematic review aimed to appraise the methodology and recommendations of nutrition CPG for critically ill patients. We performed a systematic review (protocol number CRD42020184199) with literature search conducted on PubMed, Embase, Cochrane Library and other four specific databases of guidelines up to October 2021. Two reviewers, independently, assessed titles and abstracts and potentially eligible full-text reports to determine eligibility and subsequently four reviewers appraised the guidelines quality using the Advancing Guideline Development, Reporting and Evaluation in Health Care instrument II (AGREE-II) and AGREE-Recommendation Excellence (AGREE-REX). Ten CPG for nutrition in critically ill patients were identified. Only Academy of Nutrition and Dietetics and European Society of Intensive Care Medicine had a total acceptable quality and were recommended for daily practice according AGREE-II. None of the CPG recommendations had an overall quality score above 70 %, thus being classified as moderate quality according AGREE-REX. The methodological evaluation of the critically ill adult patient CPG revealed significant discrepancies and showed a need for improvement in its development and/or reporting. In addition, recommendations about nutrition care process presented a moderate quality.

The excessive intake of ultra-processed foods (UPF) is associated with an increase in cardiovascular risk. However, the effect of UPF intake on cardiovascular health in children and adolescents with congenital heart disease (CHD) is unknown. The aim of the present study was to describe UPF intake and evaluate associations with isolated cardiovascular risk factors and children and adolescents with CHD clustered by cardiovascular risk factors. A cross-sectional study was conducted involving 232 children and adolescents with CHD. Dietary intake was assessed using three 24-hour recalls. UPF were categorised using the NOVA classification. The cardiovascular risk factors evaluated were central adiposity, elevated high-sensitivity C-reactive protein (hs-CRP) and subclinical atherosclerosis. The clustering of cardiovascular risk factors (waist circumference, hs-CRP and carotid intima-media thickness) was performed, allocating the participants to two groups (high v. low cardiovascular risk). UPF contributed 40·69 % (sd 6·21) to total energy intake. The main UPF groups were ready-to-eat and take-away/fast foods (22·2 % energy from UPF). The multivariable logistic regression revealed that an absolute increase of 10 % in UPF intake (OR = 1·90; 95 % CI: 1·01;3·58) was associated with central adiposity. An absolute increase of 10 % in UPF intake (OR = 3·77; 95 % CI: 1·80, 7·87) was also associated with children and adolescents with CHD clustered by high cardiovascular risk after adjusting for confounding factors. Our findings demonstrate that UPF intake should be considered as a modifiable risk factor for obesity and its cardiovascular consequences in children and adolescents with CHD.

This exploratory study investigated the effects of early v. delayed time-restricted eating (TRE) plus caloric restriction (CR) on body weight, body composition and cardiometabolic parameters in adults with overweight and obesity. Adults (20–40 years) were randomised to one of three groups for 8 weeks: early time-restricted eating (eTRE; 08.00–16.00) plus CR, delayed time-restricted eating (dTRE; 12.00–20.00) plus CR or only CR (CR; 08.00–20.00). All groups were prescribed a 25 % energy deficit relative to daily energy requirements. Thirteen participants completed the study in the eTRE and CR groups and eleven in the dTRE group (n 37). After the interventions, there was no significant difference between the three groups for any of the outcomes. Compared with baseline, significant decreases were observed in the body weight (eTRE group: −4·2 kg; 95 % CI, −5·6, −2·7; dTRE group: −4·8 kg; 95 % CI, −5·9, −3·7; CR: −4·0 kg; 95 % CI, −5·9, −2·1), fat mass (eTRE group: −2·9 kg; 95 % CI, −3·9, −1·9; dTRE group: −3·6 kg; 95 % CI, −4·6, −2·5; CR: −3·1 kg; 95 % CI, −4·3, −1·8) and fasting glucose levels (eTRE group: −4 mg/dl; 95 % CI, −8, −1; dTRE group: −2 mg/dl; 95 % CI, −8, 3; CR: −3 mg/dl; 95 % CI, −8, 2). In a free-living setting, TRE with a energetic deficit, regardless of the time of day, promotes similar benefits in weight loss, body composition and cardiometabolic parameters. However, given the exploratory nature of our study, further investigation is needed to confirm these findings.

Childhood malnutrition is known as a public health concern globally. The present study aims to assess the anthropometry and blood biochemical status of rural primary schoolchildren in Malaysia. A total of 776 children (7–11 years old) from ten rural primary schools from five states were included in this study. Nutritional outcomes were assessed based on sex, age group and school categories among the children (median age: 9 years (P25:8, P75:10)). The overall prevalence of malnutrition was 53·4 %. Vitamin A deficiency (VAD) was recorded at 20·6 and 39·8 % based on retinol and retinol-binding protein (RBP) levels, respectively. Anaemia, iron deficiency (ID), iron-deficiency anaemia (IDA) and elevated inflammation were found at 14·9, 17·9, 9·1 and 11·5 %, respectively. Malnutrition, VAD, anaemia, ID, IDA and elevated inflammation were more prevalent among Orang Asli (OA) schoolchildren compared with Non-Orang Asli schoolchildren. Higher occurrences of VAD and anaemia were also found among children aged <10 years. Retinol, RBP, α-carotene, ferritin and haemoglobin levels were lower among undernourished children. Besides, overweight/obese children exhibited a higher level of high-sensitivity C-reactive protein. Multivariate analysis demonstrated that OA school children (adjusted OR (AOR): 6·1; 95 % CI 4·1, 9·0) and IDA (AOR: 3·6; 95 % CI 1·9, 6·6) were associated with stunting among this population. The present study revealed that malnutrition, micronutrient deficiencies and anaemia are prevalent among rural primary schoolchildren in Malaysia, especially those from OA schools and younger age children (<10 years). Hence, more appropriate and targeted measures are needed to improve the nutritional status of these children.

It has been suggested that added sugar intake is associated with non-alcoholic fatty liver disease (NAFLD). However, previous studies only focused on sugar-sweetened beverages; the evidence for associations with total added sugars and their sources is scarce. This study aimed to examine the associations of total added sugars, their physical forms (liquid v. solid) and food sources with risk of NAFLD among adults in Tianjin, China. We used data from 15 538 participants, free of NAFLD, other liver diseases, CVD, cancer or diabetes at baseline (2013–2018 years). Added sugar intake was estimated from a validated 100-item FFQ. NAFLD was diagnosed by ultrasonography after exclusion of other causes of liver diseases. Multivariable Cox proportional hazards models were fitted to calculate hazard ratios (HR) and corresponding 95 % CI for NAFLD risk with added sugar intake. During a median follow-up of 4·2 years, 3476 incident NAFLD cases were documented. After adjusting for age, sex, BMI and its change from baseline to follow-up, lifestyle factors, personal and family medical history and overall diet quality, the multivariable HR of NAFLD risk were 1·18 (95 % CI 1·06, 1·32) for total added sugars, 1·20 (95 % CI 1·08, 1·33) for liquid added sugars and 0·96 (95 % CI 0·86, 1·07) for solid added sugars when comparing the highest quartiles of intake with the lowest quartiles of intake. In this prospective cohort of Chinese adults, higher intakes of total added sugars and liquid added sugars, but not solid added sugars, were associated with a higher risk of NAFLD.

Depression is a chronic and complex condition experienced by over 300 million people worldwide. While research on the impact of nutrition on chronic physical illness is well documented, there is growing interest in the role of dietary patterns for those experiencing symptoms of depression. This study aims to examine the association of diet quality (Dietary Questionnaire for Epidemiological Studies version 2) and depressive symptoms (Centre for Epidemiological Studies for Depression short form) of young Australian women over 6 years at two time points, 2003 (n 9081, Mean age = 27·6) and 2009 (n 8199, Mean age = 33·7) using secondary data from the Australian Longitudinal Study on Women’s Health. A linear mixed-effects model found a small and significant inverse association of diet quality on depressive symptoms (β = −0·03, 95 % CI (−0·04, −0·02)) after adjusting for covarying factors such as BMI, social functioning, alcohol and smoking status. These findings suggest that the continuation of a healthy dietary pattern may be protective of depressive symptoms. Caution should be applied in interpreting these findings due to the small effect sizes. More longitudinal studies are needed to assess temporal relationships between dietary quality and depression.

The main aim of this study was to evaluate the effects of Na intake and cardiorespiratory fitness (CRF) on body composition. The study was also intended to assess whether Na intake and/or CRF mediate the genetic susceptibility to obesity. Analyses were performed on a sample of 526 adult participants from the Quebec Family Study for whom a complete data set was available for nutrient and energy intake, CRF and body composition variables. The effects of Na, CRF and their interaction were analysed by comparing sex-specific tertiles using general linear mixed models. In both males and females, we observed a significant effect of Na intake and CRF on all body composition variables. However, in females only, we found that the effect of Na intake on body composition variables varies according to CRF level such that high Na intake was associated with increased body fatness, but only in females with low CRF. This interaction effect remained significant after statistical adjustment for total sugar, fat and energy intake. Using mediation analysis, we also found Na intake and CRF to be significant mediators of the relationship between a polygenic risk score of obesity based on > 500 000 genetic variants and BMI or waist circumference. In conclusion, the current study shows that Na intake influences body composition via mechanisms that interact with aerobic fitness, especially in females. Furthermore, both Na intake and CRF seem to be involved in the expression of the genetic susceptibility to obesity.

This study aimed to determine whether higher intakes of Na, added sugars and saturated fat are prospectively associated with all-cause mortality and CVD incidence and mortality in a diverse population. The nationally representative Canadian Community Health Survey-Nutrition 2004 was linked with the Canadian Vital Statistics – Death Database and the Discharge Abstract Database (2004–2011). Outcomes were all-cause mortality and CVD incidence and mortality. There were 1722 mortality cases within 115 566 person-years of follow-up (median (interquartile range) of 7·48 (7·22–7·70) years). There was no statistically significant association between Na density or energy from saturated fat and all-cause mortality or CVD events for all models investigated. The association of usual percentage of energy from added sugars and all-cause mortality was significant in the base model with participants consuming 11·47 % of energy from added sugars having 1·34 (95 % CI 1·01, 1·77) times higher risk of all-cause mortality compared with those consuming 4·17 % of energy from added sugars. Overall, our results did not find statistically significant associations between the three nutrients and risk of all-cause mortality or CVD events at the population level in Canada. Large-scale linked national nutrition datasets may not have the discrimination to identify prospective impacts of nutrients on health measures.

Milk is a source of several nutrients which may be beneficial for skeletal muscle. Evidence that links lower milk intake with declines in muscle strength from midlife to old age is lacking. We used data from the Medical Research Council National Survey of Health and Development to test sex-specific associations between milk consumption from age 36 to 60–64 years, low grip strength (GS) or probable sarcopenia, and GS decline from age 53 to 69 years. We included 1340 men and 1383 women with at least one measure of both milk intake and GS. Milk intake was recorded in 5-d food diaries (aged 36, 43, 53 and 60–64 years), and grand mean of total, reduced-fat and full-fat milk each categorised in thirds (T1 (lowest) to T3 (highest), g/d). GS was assessed at ages 53, 60–64, and 69 years, and probable sarcopenia classified at the age of 69 years. We employed logistic regression to examine the odds of probable sarcopenia and multilevel models to investigate decline in GS in relation to milk intake thirds. Compared with T1, only T2 (58·76–145·25 g/d) of reduced-fat milk was associated with lower odds of sex-specific low GS at the age of 69 years (OR (95 % CI): 0·59 (0·37, 0·94), P = 0·03). In multilevel models, only T3 of total milk (≥ 237·52 g/d) was associated with stronger GS in midlife in men (β (95 % CI) = 1·82 (0·18, 3·45) kg, P = 0·03) compared with T1 (≤ 152·0 g/d), but not with GS decline over time. A higher milk intake across adulthood may promote muscle strength in midlife in men. Its role in muscle health in late life needs further examination.

Vitamin D seasonality has been reported in adults and children, suggesting that sunlight exposure has effects on 25(OH)D production. While vitamin D deficiency among infants has received significant attention, little is known about the extent to which vitamin D status during early infancy is affected by sunlight exposure. Here, we retrospectively analysed serum 25(OH)D levels of 692 samples obtained from healthy infants aged 1–2 months born at Saitama City Hospital, Japan (latitude 35·9° North) between August 2017 and September 2021. Data regarding the frequency of outdoor activities, formula intake and BMI were also collected and analysed. Month-to-month comparisons of vitamin D levels revealed significant variation in 25(OH)D levels in breastfed infants starting at 2 months, with maximal and minimal levels in September and January, respectively. An outdoor activity score of 0 was most common at 1 month (83·9 %) and a score of 3 was most common at 2 months (81·2 %), suggesting an increased amount of sunlight exposure at 2 months. Multiple linear regression analysis revealed the amount of formula intake to be significantly associated with vitamin D status at both 1 (t = 17·96) and 2 months (t = 16·30). Our results comprise the first evidence that seasonal variation of vitamin D begins at 2 months among breastfed infants from East Asia, though dietary intake appears to be the major determinant of vitamin D status. These findings provide new insights into the influence of dietary and non-dietary factors on vitamin D status during early infancy.

Millet is a grain high in polyphenols and antioxidants, which are bioactive compounds known to influence blood glucose response. The aim of this study was to compare the effect of finger millet muffin and wheat muffin on glycaemic response (GR), insulin response (IR), gastric emptying (GE) and satiety in healthy individuals and people with prediabetes. In a single-blind randomised controlled crossover trial at Oxford Brookes Centre for Nutrition and Health, fifteen healthy individuals and fourteen individuals with prediabetes were recruited between May and December 2017. The participants’ GR (3 h), IR (3 h), GE (4 h) and satiety (4 h) were measured before and after the consumption of muffins. A mixed method ANOVA was used to compare GE and the incremental AUC (iAUC) for GR and IR between the participant groups and muffins. There was a significant interaction between participants and muffins on IR iAUC at 180 min (P = 0·042). A significant effect of muffins was found on the GR peak (P = 0·013). The millet muffin decreased the GR peak and IR iAUC compared with the wheat muffin in participants with prediabetes. A significant interaction between participants and muffins for GE ascension time Tasc (P = 0·017) was observed, with no effect of muffins on satiety AUC in the participant groups. This study suggested that polyphenol and fibre-rich finger millet may have the potential to influence the management of prediabetes.

Although biological evidence suggests that tea consumption may protect against non-Hodgkin lymphoma (NHL), epidemiological evidence has been unclear. The aim of this study was to examine the association between tea-drinking habits and the risk of NHL in a large nationwide prospective cohort of postmenopausal US women. 68 854 women who were enrolled from 1993 through 1998 in the Women’s Health Initiative Observational Study and responded to year 3 annual follow-up questionnaire comprised the analytic cohort. Newly diagnosed NHL cases after the year 3 visit were confirmed by medical and pathology reports. Multivariable-adjusted Cox proportional hazards models were performed to assess the associations of tea-drinking habits (specifically, the amounts of caffeinated/herbal/decaffeinated tea intake) with the overall risk of NHL and three major subtypes (diffuse large B-cell lymphoma (n 195, 0·3 %), follicular lymphoma (n 128, 0·2 %) and chronic lymphocytic leukaemia/small lymphocytic lymphoma (n 51, 0·1 %)). Among 62 622 participants, a total of 663 (1·1 %) women developed NHL during a median follow-up of 16·51 (sd 6·20) years. Overall, different amounts of type-specific tea intake were not associated with the risk of NHL regardless of its histologic subtypes after adjustment for confounders. Our findings suggest that tea intake at the current consumption level does not influence the risk of NHL, regardless of its histologic types.

COVID-19 has further exacerbated trends of widening health inequalities in the UK. Shockingly, the number of years of life lived in general good health differs by over 18 years between the most and least deprived areas of England. Poor diets and obesity are established major risk factors for chronic cardiometabolic diseases and cancer, as well as severe COVID-19. For doctors to provide the best care to their patients, there is an urgent need to improve nutrition education in undergraduate medical school training.

With this imperative, the Association for Nutrition established an Interprofessional Working Group on Medical Education (AfN IPG) to develop a new, modern undergraduate nutrition curriculum for medical doctors. The AfN IPG brought together expertise from nutrition, dietetic and medical professionals, representing the National Health Service (NHS), royal colleges, medical schools and universities, government public health departments, learned societies, medical students, and nutrition educators. The curriculum was developed with the key objective of being implementable through integration with the current undergraduate training of medical doctors.

Through an iterative and transparent consultative process, thirteen key nutritional competencies, to be achieved through mastery of eleven graduation fundamentals, were established. The curriculum to facilitate the achievement of these key competencies is divided into eight topic areas, each underpinned by a learning objective statement and teaching points detailing the knowledge and skills development required. The teaching points can be achieved through clinical teaching and a combination of facilitated learning activities and practical skill acquisition. Therefore, the nutrition curriculum enables mastery of these nutritional competencies in a way that will complement and strengthen medical students’ achievement of the General Medical Council (GMC) Outcome for Graduates.

As nutrition is an integrative science, the AfN IPG recommends that the curriculum is incorporated into initial undergraduate medical studies before specialist training. This will enable our future doctors to recognise how nutrition is related to multiple aspects of their training, from physiological systems to patient-centred care, and acquire a broad, inclusive understanding of health and disease. In addition, it will facilitate medical schools to embed nutrition learning opportunities within the core medical training, without the need to add in a large number of new components to an already crowded programme or with additional burden for teaching staff.

The undergraduate nutrition curriculum for medical doctors is designed to support medical schools to create future doctors who will understand and recognise the role of nutrition in health. Moreover, it will equip frontline staff to feel empowered to raise nutrition-related issues with their patients as a fundamental part of enhanced care and to appropriately refer on for nutrition support with a registered associate nutritionist/registered nutritionist (ANutr/RNutr) or registered dietitian (RD) where this is likely to be beneficial.

Recent studies have focused on habitual intake without addressing meal-specific intakes. We aimed to identify meal-specific dietary patterns and their contribution to habitual dietary patterns. This cross-sectional study was conducted on 838 adults, both sexes who attended the health centres in Tehran. Dietary data were recorded by three 24-h dietary recalls (24hDR). Dietary patterns were identified by using principal component analysis on meal-specific and overall food intakes. Intraclass correlation (ICC) was used as a measurement of consistency across meals and days. Correlation analysis and linear regression (partial R 2) were used for meals contribution. Four habitual dietary patterns were derived from average dietary intake of 3-d 24hDR labelled as ‘Western’, ‘Healthy’, ‘Traditional’ and ‘Legume and broth’. Also, we identified two major dietary patterns on each meal level (factor 1 and 2 for breakfast, lunch, afternoon snack and dinner). The highest contribution of energy intake was observed in lunch (25·7 %), followed by dinner (20·81 %). Consistency of food groups was the highest across days (ICC tea = 0·58) and breakfasts (ICC tea = 0·60). Dinner had a strong correlation coefficient with the ‘Western’ habitual dietary pattern then followed by lunch. Similarly, dinner and lunch contributed the most (r and partial R 2) to the ‘Western’ habitual dietary pattern. Our results suggest that habitual dietary patterns to several extents are formed at meal levels, and dinner has a greater contribution to the habitual dietary patterns in Iranian people. This may help planning for local dietary guidelines according to the time of eating to promote public health.

Folate and vitamin B12 are essential for growth. Our objective was to estimate their long-term effects on linear growth in North Indian children. This is a follow-up study of a factorial designed, double-blind, randomised, placebo-controlled trial in 1000 young children. Starting at 6–30 months of age, we gave folic acid (approximately 2 RDA), vitamin B12 (approximately 2 RDA), both vitamins or a placebo daily for 6 months. Six years after the end of supplementation, we measured height in 791 children. We used the plasma concentrations of cobalamin, folate and total homocysteine to estimate vitamin status. The effect of the interventions, the association between height-for-age z-scores (HAZ) and baseline vitamin status, and the interactions between supplementation and baseline status were estimated in multiple regression models. Mean (sd) age at follow-up was 7·4 (0·7) years (range 6 to 9 years). There was a small, non-significant effect of vitamin B12 on linear growth and no effect of folic acid. We observed a subgroup effect of vitamin B12 supplementation in those with plasma cobalamin concentration < 200 pmol/l (P for interaction = 0·01). The effect of vitamin B12 supplementation in this group was 0·34 HAZ (95 % CI 0·11, 0·58). We found an association between cobalamin status and HAZ in children not given vitamin B12 (P for interaction = 0·001). In this group, each doubling of the cobalamin concentration was associated with 0·26 (95 % CI 0·15, 0·38) higher HAZ. Suboptimal vitamin B12 status in early childhood seemingly limits linear growth in North Indian children.

Studies exploring the accuracy of equations calculating resting energy expenditure (REE) in patients with Crohn’s disease (CD) are lacking. The aim of this study was to investigate the accuracy of REE predictive equations against indirect calorimetry in CD patients. REE was measured using indirect calorimetry (mREE) after an overnight fasting. Fourteen predictive equations, with and without body composition analysis parameters, were compared with mREE using different body weight approaches. Body composition analysis was performed using dual X-ray absorptiometry. One hundred and eighty-six CD outpatients (102 males) with mean age 41·3 (sd 14·1) years and 37·6 % with active disease were evaluated. Mean mREE in the total sample was 7255 (sd 1854) kJ/day. All equations underpredicted REE and showed moderate correlations with mREE (Pearson’s r or Spearman’s rho 0·600–0·680 for current weight, all P-values < 0·001). Accuracy was low for all equations at the individual level (28–42 and 25–40 % for current and adjusted body weight, respectively, 19–33 % for equations including body composition parameters). At the group level, accuracy showed wide limits of agreement and proportional biases. Accuracy remained low when sample was studied according to disease activity, sex, BMI and medication use. All predictive equations underestimated REE and showed low accuracy. Indirect calorimetry remains the best method for estimating REE of patients with CD.

This study evaluated the association between ultra-processed foods (UPF) on serum IL-6 and to investigate the mediation role of adiposity. Participants were 524 adults from the EPITeen Cohort (Porto, Portugal) and 2888 participants from the 1982 Pelotas Birth Cohort (Pelotas, Brazil). Dietary intake was collected using FFQ when participants were 21 years of age in the EPITeen and 23 years in the Pelotas Cohort. Serum IL-6 and body fat mass were evaluated when participants were 27 and 30 years old in the EPITeen and Pelotas, respectively. Generalised linear models were fitted to test main associations. Mediation of body fat mass was estimated using G-computation. After adjustment for socio-economic and behaviour variables, among females from the EPITeen, the concentration of IL-6 (pg/ml) increased with increasing intake of UPF from 1·31 (95 % CI 0·95, 1·82) in the first UPF quartile to 2·20 (95 % CI 1·60, 3·01) and 2·64 (95 % CI 1·89, 3·69) for the third and fourth UPF quartiles, respectively. A similar result was found among males in the Pelotas Cohort, IL-6 increased from 1·40 (95 % CI 1·32, 1·49) in the first UPF quartile to 1·50 (95 % CI 1·41, 1·59) and 1·59 (95 % CI 1·49, 1·70) in the two highest UPF quartiles. The P-value for the linear trend was < 0·01 in both findings. The indirect effect through fat mass was NS. Our findings suggest that the consumption of UPF was associated with an increase in IL-6 concentration; however, this association was not explained by adiposity.

Iron deficiency is the leading cause of anaemia. In Argentina, the prevalence of anaemia and iron deficiency is very high; for that reason, the Argentine Society of Pediatrics recommends daily ferrous sulphate supplementation as a preventive treatment strategy. Alternatively, weekly ferrous sulphate supplementation has also been shown to be effective for anaemia prevention. Excess iron could be related to oxidative stress, which may in turn cause cytomolecular damage. Both can be prevented with vitamin E supplementation. We evaluated the effect of both daily and weekly ferrous sulphate supplementation combined with two doses of vitamin E on cell viability, oxidative stress and cytomolecular damage in peripheral blood cultured in vitro. The experimental design included the following groups: untreated negative control, two vitamin E controls (8·3 and 16·6 µg/ml), weekly ferrous sulphate supplementation (0·55 mg/ml) with each vitamin E dose, daily ferrous sulphate supplementation (0·14 mg/ml) with each vitamin E dose and a positive control. Daily ferrous sulphate supplementation decreased cell viability and increased the levels of reactive oxygen species, lipid peroxidation and cytomolecular damage (P < 0·5) compared with the weekly supplementation, probably due to the excess iron observed in the former. Vitamin E seemed to reduce ferrous sulphate-induced oxidative stress and genomic damage.

This study systematically reviewed the evidence on interventions seeking to improve Food and Nutrition Literacy (FNLIT) functional, interactive and critical skills in primary school-aged children. Electronic databases, including PubMed/MEDLINE, SCOPUS, Web of Science, Cochrane, Pro-Quest and Google Scholar were systematically searched. Randomised and non-randomised controlled trials, pre-/post-test and case–control designs were included. The primary outcomes were three levels of FNLIT: functional, interactive and critical. All citations, full-text articles and abstract data were screened by two independent reviewers. Any conflicts were then resolved through discussion. The quality of the included studies was individually evaluated using the Effective Public Health Practice Project (EPHPP) quality assessment tool. Two reviewers extracted data from the included studies, and a descriptive analysis was performed. The quality of all eligible studies (n 19) was rated as moderate/weak. A wide variety of skill-building activities were introduced by programmes, including recipe skills/food preparation, food label literacy, food tasting, gardening harvesting, and supporting cultural practices and ethnic foods. Only four studies measured food literacy (FL) (food label literacy) via a valid measure. Most interventions focused on the functional level of FL, except for two programmes (one scored weak and one scored moderate). In most of the studies, delivery of intervention content was facilitated by teachers (n 15). Promising interventions were tailored to the needs and interests of students, incorporated into the existing curriculum and facilitated by teachers. The successful intervention strategies led to improvements in functional, partly interactive and critical skills. Future interventions should focus, holistically, on all aspects of FNLIT, especially interactive and critical skills.