Association of glycaemic index and glycaemic load with type 2 diabetes, cardiovascular disease, cancer, and all-cause mortality: a meta-analysis of mega cohorts of more than 100 000 participants.

BACKGROUND: There is debate over whether the glycaemic index of foods relates to chronic disease. We aimed to assess the associations between glycaemic index (GI) and glycaemic load (GL) and type 2 diabetes, cardiovascular disease, diabetes-related cancers, and all-cause mortality. METHODS: We did a meta-analysis of large cohorts (≥100 000 participants) identified from the Richard Doll Consortium. We searched the Cochrane Library, MEDLINE, PubMed, Embase, Web of Science, and Scopus for cohorts that prospectively examined associations between GI or GL and chronic disease outcomes published from database inception to Aug 4, 2023. Full-article review and extraction of summary estimates data were conducted by three independent reviewers. Primary outcomes were incident type 2 diabetes, total cardiovascular disease (including mortality), diabetes-related cancers (ie, bladder, breast, colorectal, endometrial, hepatic, pancreatic, and non-Hodgkin lymphoma), and all-cause mortality. We assessed comparisons between the lowest and highest quantiles of GI and GL, adjusting for dietary factors, and pooling their most adjusted relative risk (RR) estimates using a fixed-effects model. We also assessed associations between diets high in fibre and whole grains and the four main outcomes. The study protocol is registered with PROSPERO, CRD42023394689. FINDINGS: From ten prospective large cohorts (six from the USA, one from Europe, two from Asia, and one international), we identified a total of 48 studies reporting associations between GI or GL and the outcomes of interest: 34 (71%) on various cancers, nine (19%) on cardiovascular disease, five (10%) on type 2 diabetes, and three (6%) on all-cause mortality. Consumption of high GI foods was associated with an increased incidence of type 2 diabetes (RR 1·27 [95% CI 1·21-1·34]; p<0·0001), total cardiovascular disease (1·15 [1·11-1·19]; p<0·0001), diabetes-related cancer (1·05 [1·02-1·08]; p=0·0010), and all-cause mortality (1·08 [1·05-1·12]; p<0·0001). Similar associations were seen between high GL and diabetes (RR 1·15 [95% CI 1·09-1·21]; p<0·0001) and total cardiovascular disease (1·15 [1·10-1·20]; p<0·0001). Associations between diets high in fibre and whole grains and the four main outcomes were similar to those for low GI diets. INTERPRETATION: Dietary recommendations to reduce GI and GL could have effects on health outcomes that are similar to outcomes of recommendations to increase intake of fibre and whole grain. FUNDING: Banting and Best and the Karuna Foundation.

Portfolio Diet Score and Risk of Cardiovascular Disease: Findings From 3 Prospective Cohort Studies.

BACKGROUND: The plant-based Portfolio dietary pattern includes recognized cholesterol-lowering foods (ie, plant protein, nuts, viscous fiber, phytosterols, and plant monounsaturated fats) shown to improve several cardiovascular disease (CVD) risk factors in randomized controlled trials. However, there is limited evidence on the role of long-term adherence to the diet and CVD risk. The primary objective was to examine the relationship between the Portfolio Diet Score (PDS) and the risk of total CVD, coronary heart disease (CHD), and stroke. METHODS: We prospectively followed 73 924 women in the Nurses' Health Study (1984-2016), 92 346 women in the Nurses' Health Study II (1991-2017), and 43 970 men in the Health Professionals Follow-up Study (1986-2016) without CVD or cancer at baseline. Diet was assessed using validated food frequency questionnaires at baseline and every 4 years using a PDS that positively ranks plant protein (legumes), nuts and seeds, viscous fiber sources, phytosterols (mg/day), and plant monounsaturated fat sources, and negatively ranks foods high in saturated fat and cholesterol. RESULTS: During up to 30 years of follow-up, 16 917 incident CVD cases, including 10 666 CHD cases and 6473 strokes, were documented. After multivariable adjustment for lifestyle factors and a modified Alternate Healthy Eating Index (excluding overlapping components), comparing the highest with the lowest quintile, participants with a higher PDS had a lower risk of total CVD (pooled hazard ratio [HR], 0.86 [95% CI, 0.81-0.92]; Ptrend<0.001), CHD (pooled HR, 0.86 [95% CI, 0.80-0.93]; Ptrend=0.0001), and stroke (pooled HR, 0.86 [95% CI, 0.78-0.95]; Ptrend=0.0003). In addition, a 25-percentile higher PDS was associated with a lower risk of total CVD (pooled HR, 0.92 [95% CI, 0.89-0.95]), CHD (pooled HR, 0.92 [95% CI, 0.88-0.95]), and stroke (pooled HR, 0.92 [95% CI, 0.87-0.96]). Results remained consistent across sensitivity and most subgroup analyses, and there was no evidence of departure from linearity for CVD, CHD, or stroke. In a subset of participants, a higher PDS was associated with a more favorable blood lipid and inflammatory profile. CONCLUSIONS: The PDS was associated with a lower risk of CVD, including CHD and stroke, and a more favorable blood lipid and inflammatory profile, in 3 large prospective cohorts.

The Antioxidant Capacity of Breast Milk and Plasma of Women with or without Gestational Diabetes Mellitus.

Women with gestational diabetes (GD) have reduced antioxidant capacity; however, the relationship between maternal diet, maternal biochemical capacity, breast milk concentration, and infant intake has not been adequately explored in the literature. An exploration of underlying mechanism(s) is warranted, particularly for nutrient antioxidants impacted by maternal intake. These nutrients may provide a means for modifying maternal and infant antioxidant capacity. Oxygen radical absorbance capacity (ORAC), alpha-tocopherol, ascorbic acid, and beta-carotene concentrations were measured in breast milk of women with and without GD. Plasma, three-day diet records, and breast milk were collected at 6 to 8 weeks postpartum. Student's t-test was used to compare breast milk ORAC, nutrient antioxidant concentration and plasma ORAC between women with and without GD. Pearson correlations were used to determine associations among antioxidant concentrations in breast milk and dietary antioxidant intake. Breast milk antioxidant concentrations were associated with maternal intake of beta-carotene (r = 0.629, p = 0.005). Breast milk and plasma ORAC and antioxidant vitamin concentrations were not significantly different between GD and NG women. Breast milk ORAC associated with breast milk alpha-tocopherol for NG (r = 0.763, p = 0.010), but not GD women (r = 0.385, p = 0.35), and with breast milk ascorbic acid for GD (r = 0.722, p = 0.043) but not NG women (r = 0.141, p = 0.70; interaction p = 0.041). In GD participants, breast milk ORAC was significantly associated with plasma ORAC (r = 0.780, p = 0.039). ORAC and antioxidant vitamin concentrations in breast milk in women with GD were comparable to women with NG; however, the relationships between breast milk ORAC and vitamin concentrations differed in GD versus NG women for alpha-tocopherol and ascorbic acid.

Perspective: Plant-Based Meat Alternatives Can Help Facilitate and Maintain a Lower Animal to Plant Protein Intake Ratio.

The health and environmental advantages of plant-predominant diets will likely lead to increasing numbers of consumers reducing their reliance on animal products. Consequently, health organizations and professionals will need to provide guidance on how best to make this change. In many developed countries, nearly twice as much protein is derived from animal versus plant sources. Potential benefits could result from consuming a higher share of plant protein. Advice to consume equal amounts from each source is more likely to be embraced than advice to eschew all or most animal products. However, much of the plant protein currently consumed comes from refined grains, which is unlikely to provide the benefits associated with plant-predominant diets. In contrast, legumes provide ample amounts of protein as well other components such as fiber, resistant starch, and polyphenolics, which are collectively thought to exert health benefits. But despite their many accolades and endorsement by the nutrition community, legumes make a negligible contribution to global protein intake, especially in developed countries. Furthermore, evidence suggests the consumption of cooked legumes will not substantially increase over the next several decades. We argue here that plant-based meat alternatives (PBMAs) made from legumes are a viable alternative, or a complement, to consuming legumes in the traditional manner. These products may be accepted by meat eaters because they can emulate the orosensory properties and functionality of the foods they are intended to replace. PBMAs can be both transition foods and maintenance foods in that they can facilitate the transition to a plant-predominant diet and make it easier to maintain. PBMAs also have a distinct advantage of being able to be fortified with shortfall nutrients in plant-predominant diets. Whether existing PBMAs provide similar health benefits as whole legumes, or can be formulated to do so, remains to be established.

Prospective Association of the Portfolio Diet with All-Cause and Cause-Specific Mortality Risk in the Mr. OS and Ms. OS Study.

The Portfolio Diet has demonstrated its cardiovascular benefit from interventions, but the association between Portfolio Diet adherence and the risk of all-cause and cause-specific mortality has not been examined in Chinese population. The present study has collected Portfolio Diet adherence (assessed by food frequency questionnaire), lifestyle factors and mortality status of 3991 participants in the Mr. Osteoporosis (OS) and Ms. OS Study. Cox regression models were used to examine the association between the Portfolio Diet adherence and mortality risk (all-cause, cardiovascular disease or cancer). The highest quartile of the Portfolio Diet score was associated with a 28% lower risk of all-cause (hazard ratio, HR: 0.72) and cancer (HR: 0.72) mortality, respectively. The association between Portfolio Diet adherence and cardiovascular disease mortality did not reach statistical significance (HR: 0.90, 95% CI = 0.64, 1.26). Among male participants, the highest adherence to the Portfolio Diet was also associated with a lower risk of all-cause (HR: 0.63) and cancer mortality (HR: 0.59), and there was an inverse association between food sources of plant protein and the risk of cardiovascular mortality (HR: 0.50). However, most associations between the Portfolio Diet and mortality were not significant among females. The protection for cancer mortality risk might reach the plateau at the highest adherence to the Portfolio Diet for females. To conclude, greater adherence to the Portfolio Diet was significantly associated with a lower risk of mortality in Hong Kong older adults, and the associations appeared stronger among males.

Long-term vitamin D3 supplementation does not prevent colonic inflammation or modulate bone health in IL-10 knockout mice at young adulthood.

Inflammatory bowel disease (IBD) is an idiopathic disease that can impair bone metabolism. Low vitamin D status has been implicated in its progress. This study used interleukin (IL)-10 knockout (KO) mice, that develop an intestinal inflammation when housed in a non-sterile environment, to determine if supplementation with vitamin D3 throughout life could mitigate inflammation and attenuate the lower bone mineral content (BMC) and density (BMD), and bone strength. Female IL-10 KO mice were randomized 25 or 5000 IU vitamin D3/kg diet throughout pregnancy and lactation. At weaning, offspring received the same or opposite diet as their mother until age three months. Body weight growth was similar among groups within a sex. At three months of age, there were no differences in inflammation and gene expression in the colon of offspring. Male offspring exposed to continuous 25 IU vitamin D3/kg diet had lower (p < 0.001) colonic VDR expression and those exposed only to low vitamin D3 until weaning had higher serum IL-6. There were no differences in femur or vertebral BMC, BMD or bone strength. In summary, long-term exposure to vitamin D3 did not attenuate intestinal inflammation or preserve bone mineral or bone strength. Thus, supplementation with vitamin D3 does not exert anti-inflammatory effects in this mouse model that mimics human inflammatory bowel disease.