Dietary risk factors for overweight and obesity outcomes were assessed in 25 meta-analyses across 15 SRM articles, with the diet exposure varying from dietary diversity to healthy/unhealthy dietary patterns, as well as consumption of specific food groups, including UPF, SSB, fried foods, red and processed meat, dairy products, fruit and vegetables. A healthy dietary pattern was associated with reduced risk of overweight and obesity (OR 0.64) (Mu et al. 2017). There was no evidence of an association with dietary diversity (Qorbani et al. 2022; SalehiAbargouei et al. 2016). Vegetarian and vegan diets were associated with lower BMI compared to omnivore diets (Dinu et al. 2017). Higher consumption of fruits and vegetables was associated with lower risk of overweight and obesity as well as lower waist circumference and body weight (Schwingshackl et al. 2015). Total dairy consumption also was protective in multiple studies (Feng et al. 2022; Schwingshackl et al. 2016; W. Wang, Wu, and Zhang 2016).

Evidence for dietary risk factors for higher overweight and obesity included fried food consumption (OR 1.16) as well as high consumption of SSB (RR 1.12) (Qin et al. 2020). High UPF intake was consistently associated with increased risk of overweight and obesity across four SRM, as a combined outcome (OR 1.39) (Pagliai et al. 2021) or for overweight (range OR 1.02-1.36) and obesity (range OR 1.26-1.55) (Askari et al. 2020; Lane et al. 2021; Moradi et al. 2023). While red meat consumption was not associated with obesity in a meta-analysis that included mostly HICs and only the Islamic Republic of Iran, red and processed meat intake was associated with increased risk of obesity (OR 1.37) and higher mean waist circumference and BMI (Rouhani et al. 2014). High adherence to an unhealthy ‘western’ dietary pattern was a strong risk factor for overweight/obesity in one meta-analysis of 18 studies in HICs and LMICs (OR 1.65; 95% CI 1.45, 1.87) (Mu et al. 2017) but not in a meta-analysis of 8 studies from China (OR 1.34, 95% CI 0.98, 1.84) (Jiang et al. 2022).

## **Health outcomes – diabetes and hypertension**

The SRM for adults included 24 meta-analyses with T2DM and 11 with hypertension as the outcome. In the only study that summarized the evidence for dietary diversity, there was no evidence of an association with cardiometabolic risk factors, including T2DM and hypertension (Qorbani et al. 2022). High adherence to healthy dietary patterns is protective for both T2DM and hypertension, with relative risk estimates in the range of 0.79-0.86 for T2DM (Alhazmi et al. 2014; Esposito et al. 2014; McEvoy et al. 2014; Morze et al. 2020; Maghsoudi, Ghiasvand, and Salehi-Abargouei 2016). Adherence to a vegetarian diet also was associated with lower blood glucose levels (Dinu et al. 2017) and risk of T2DM (Lee and Park 2017). The odds of hypertension were lower (OR 0.87; 95% CI 0.78, 0.98) among adults with higher adherence to a Mediterranean diet(Cowell et al. 2021). Total dairy consumption was also associated with reduced risk of T2DM and hypertension, although there were very small numbers of LMIC studies included in these estimates (Chen et al. 2022; Feng et al. 2022; Mishali et al. 2019; Khoramdad et al. 2017; D. Gao et al. 2013).

In contrast, high consumption of unhealthy foods and beverages, including UPF and SSB was associated with increased risk of T2DM and hypertension. Relative risks for diabetes incidence associated with SSB intake ranged from 1.27 to 1.38 (Neelakantan et al. 2021; B. Li et al. 2023). Adherence to unhealthy dietary patten also increased the risk of T2DM (Alhazmi et al. 2014; Maghsoudi, Ghiasvand, and Salehi-Abargouei 2016; McEvoy et al. 2014). UPF consumption significantly increased the risk of hypertension (OR 1.23; 1.11, 1.37) (M. Wang et al. 2022).

# Evidence gaps by life stage group, dietary exposures and outcomes

In **Table 8** we show a mapping of the associations observed in the included SRM by life stage group, dietary exposures and outcomes.

**Diet quality during pregnancy** – the evidence available on the risks associated with various dietary factors during pregnancy covers a wide range of maternal nutrition and health outcomes, as well as birth outcomes (e.g. LBW). Diet diversity is a common metric used to assess nutrient adequacy during pregnancy, particularly in LMICs, but is less useful for estimating the risk of pregnancy complications such as gestational diabetes and hypertension. Dietary risk factors for NCD-related outcomes were commonly assessed using specific food groups as well as

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