Dietary Intake Indices Research Articles

Effect of Dietary-Based Lifestyle Modification Approaches on Anthropometric Indices and Dietary Intake Parameters in Women with Breast Cancer: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This systematic review and meta-analysis aimed to investigate the effect of dietary-based lifestyle modification interventions ("diet," or "diet+exercise," or "diet+exercise+behavioral" intervention) on the measures of anthropometric and dietary intake parameters in women with breas cancer (BC). Databases were searched until June 2021. Inclusion criteria were randomized controlled trials that enrolled only women with BC. Studies that used exercise or behavioral interventions alone were not included. Mean±SD changes were extracted for each outcome, and pooled using a random-effects model; 7315 studies were identified. Fifty-one studies (n=7743) were included. The median ± SD duration of treatment was 24 ± 16.65 wk. Dietary-based interventions significantly reduced body weight [45 studies (n=7239), weighted mean difference (WMD) (95% CI): -2.6 (-3.2, -2.1) kg], BMI [31 studies (n=5384); WMD (95% CI): -1.0 (-1.3, -0.7) kg/m2], lean body mass [15 studies (n=1194); WMD (95% CI): -0.6(-0.7, -0.4) kg], fat mass [11 studies (n=913); WMD (95% CI): -2.6 (-3.3, -1.8) kg], fat percentage [17 studies (n=897); WMD (95% CI): -1.5 (-1.9, -1.3)%], hip circumference [9 studies (n=489); WMD (95% CI): -2.43 (-3.34, -1.54) cm], and waist circumference [7 studies (n=309); WMD (95% CI): 0.02 (-0.03, -0.005) cm]. Significant reductions in energy intakes [20 studies (n=4608), WMD (95% CI): -162 (-220, 104) kcal/d] and fat intakes [7 studies (n=4316), WMD (95% CI): -7.5 (-7.8, -7.2)% of energy/d], and an increase in fiber intakes [11 studies (n=4241), WMD (95% CI): 2.4 (0.7, 4.1) g/d] were observed. No significant changes were seen in protein, carbohydrate, and fruit and vegetable intakes. Subgroup analyses showed that changes in anthropometric and dietary intake indices were significant in studies that enrolled patients with both obesity and normal weight, studies that used diet therapy in combination with exercise and behavioral therapy, and studies that started the intervention during the treatment period. Overall, a multimodal dietary-based lifestyle intervention had significant effects on anthropometric and dietary intake parameters in women with BC, specifically when started as early as the diagnosis. This meta-analysis was registered at PROSPERO as CRD42021291488.

Vitamin A and cancers of the breast, large bowel, and prostate: epidemiologic evidence.

In this review we have examined epidemiological data from a variety of sources to assess the relation between vitamin A intake and cancer risk. The potential for recall bias in case-control studies makes their interpretation difficult, particularly if we are searching for modest associations. Prospective data are preferable, but sparse. Studies of blood levels of carotenoids may be informative if the blood is stored at ultra-low temperatures; however, studies of blood retinol levels are largely uninformative as an index of dietary intake because blood retinol is not well correlated with intake except in vitamin A-deficient populations. We have also reviewed the evidence for an influence of vitamin A intake on the incidence of cancer at the three major cancer sites accounting for a substantial portion of cancers in developed countries. The available data are compatible with a modest inverse association between intake of vitamin A and breast cancer, although it is not clear whether this effect may be due to preformed vitamin A, carotenoids, or both. The evidence that vitamin A protects against colon cancer is unconvincing. In the case of prostate cancer, early suggestions that vitamin A may increase incidence have not been confirmed by subsequent studies. Fortunately, prospective data from a number of large ongoing cohort studies in the United States and Europe should be available within the next 5 years or so. These data will permit further assessment of potential correlations between vitamin A and cancer at various sites by analysis of much larger numbers of cases than are presently available.(ABSTRACT TRUNCATED AT 250 WORDS)