A Systematic Literature Review and Meta-Regression Analysis on Early-Life Energy Restriction and Cancer Risk in Humans

Effect of Intermittent vs. Continuous Energy Restriction on Visceral Fat: Protocol for The Healthy Diet and Lifestyle Study 2 (HDLS2)

Obesity in the United States and Western countries represents a major health challenge associated with an increased risk of metabolic diseases, including cardiovascular disease, hypertension, diabetes, and certain cancers. Our past work revealed a more pronounced obesity-cancer link in certain ethnic groups, motivating us to develop a tailored dietary intervention called the Healthy Diet and Lifestyle 2 (HDLS2). The study protocol is described herein for this randomized six-month trial examining the effects of intermittent energy restriction (5:2 Diet) plus the Mediterranean dietary pattern (IER + MED) on visceral adipose tissue (VAT), liver fat, and metabolic biomarkers, compared to a standard MED with daily energy restriction (DER + MED), in a diverse participant group. Using MRI and DXA scans for body composition analysis, as well as metabolic profiling, this research aims to contribute to nutritional guidelines and strategies for visceral obesity reduction. The potential benefits of IER + MED, particularly regarding VAT reduction and metabolic health improvement, could be pivotal in mitigating the obesity epidemic and its metabolic sequelae. The ongoing study will provide essential insights into the efficacy of these energy restriction approaches across varied racial/ethnic backgrounds, addressing an urgent need in nutrition and metabolic health research. Registered Trial, National Institutes of Health, ClinicalTrials.gov (NCT05132686).

Translating energy balance research from the bench to the clinic to the community: Parallel animal-human studies in cancer

Advances in energy balance and cancer research to date have largely occurred in siloed work in rodents or patients. However, substantial benefit can be derived from parallel studies in which animal models inform the design of clinical and population studies or in which clinical observations become the basis for animal studies. The conference Translating Energy Balance from Bench to Communities: Application of Parallel Animal-Human Studies in Cancer, held in July 2021, convened investigators from basic, translational/clinical, and population science research to share knowledge, examples of successful parallel studies, and strong research to move the field of energy balance and cancer toward practice changes. This review summarizes key topics discussed to advance research on the role of energy balance, including physical activity, body composition, and dietary intake, on cancer development, cancer outcomes, and healthy survivorship.

Diets, Dietary Patterns, Single Foods and Pancreatic Cancer Risk: An Umbrella Review of Meta-Analyses

Pancreatic cancer (PC) represents the third leading cause of cancer death in 2020. Despite the fact that, in 2018, the World Cancer Research Fund report concluded that there is still a lack of evidence on the role of foods or diets and risk for PC, a flourishing body of evidence has been published and needs to be analyzed. For this reason, we conducted an umbrella review on the association between different dietary patterns/food components and PC. Data sources PubMed/MEDLINE, Scopus, Web of Science, EMBASE, and the Cochrane Collaboration were searched. The Joanna Briggs Institute Umbrella Review Methodology was used. The protocol was registered in PROSPERO. A total of 23 articles were included, covering a wide range of dietary patterns/food components: healthy/prudent dietary patterns (n = 4), Mediterranean diets (MedDiet) (n = 1), plant-based diets (n = 2), the Dietary Inflammatory Index (DII) (n = 2), western diets (n = 2), and, lastly, unhealthy diets (n = 2). Regarding dietary components, the following were assessed: total fruit (n = 2), citrus fruit (n = 1), total vegetables (n = 2), cruciferous vegetables (n = 1), red meat (n = 6), processed meat (n = 4), poultry (n = 2), eggs (n = 1), fish (n = 5), whole grain (n = 2), potato (n = 1), and nuts (n = 2). The methodological quality of the included meta-analyses was generally low or critically low. Although the strength of evidence was generally weak, convincing or suggestive evidence was found for a healthy/prudent, plant-based diet, fruit and vegetables, and lower risk of PC, whereas a high intake of red meat was associated with a higher risk of PC at a convincing level of evidence. Further studies are needed to confirm the role of the other dietary patterns/food components and the risk of PC.

Growth Rate in Childhood and Adolescence and the Risk of Breast and Prostate Cancer: A Population-Based Study

Growth rate is regulated by hormonal pathways that might affect early cancer development. We explored the association between rate of growth in height from ages 8 to 13 years (childhood) and from age 13 to attainment of adult height (adolescence), as measured at study entry, and the risk of breast or prostate cancer. Participants were 2,037 Icelanders born during 1915-1935, who took part in the Reykjavik Study, established in 1967. Height measurements were obtained from school records and at study entry. We used multivariable Cox regression models to calculate hazard ratios with 95% confidence intervals of breast and prostate cancer by rates of growth in tertiles. During a mean follow-up of 66 years (women) and 64 years (men), 117 women were diagnosed with breast cancer and 118 men with prostate cancer (45 with advanced disease). Women in the highest growth-rate tertile in adolescence had a higher risk of breast cancer (hazard ratio = 2.4, 95% confidence interval: 1.3, 4.3) compared with women in the lowest tertile. A suggestive inverse association was observed for highest adolescent growth rate in men and advanced prostate cancer: hazard ratio = 0.4, 95% confidence interval: 0.2, 1.0. Rapid growth, particularly in adolescence may affect cancer risk later in life.

Energy balance‐related factors in childhood and adolescence and risk of colorectal cancer expressing different levels of proteins involved in the Warburg‐effect

Early‐life (childhood to adolescence) energy balance‐related factors (height, energy restriction, BMI) have been associated with adult colorectal cancer (CRC) risk. Warburg‐effect activation via PI3K/Akt‐signaling might explain this link. We investigated whether early‐life energy balance‐related factors were associated with risk of Warburg‐subtypes in CRC. We used immunohistochemistry for six proteins involved in the Warburg‐effect (LDHA, GLUT1, MCT4, PKM2, P53, and PTEN) on tissue microarrays of 2399 incident CRC cases from the prospective Netherlands Cohort Study (NLCS). Expression levels of all proteins were combined into a pathway‐based sum score and categorized into three Warburg‐subtypes (Warburg‐low/‐moderate/‐high). Multivariable Cox‐regression analyses were used to estimate associations of height, energy restriction proxies (exposure to Dutch Hunger Winter; Second World War [WWII]; Economic Depression) and adolescent BMI with Warburg‐subtypes in CRC. Height was positively associated with colon cancer in men, regardless of Warburg‐subtypes, and with Warburg‐low colon and Warburg‐moderate rectal cancer in women. Energy restriction during the Dutch Hunger Winter was inversely associated with colon cancer in men, regardless of Warburg‐subtypes. In women, energy restriction during the Hunger Winter and WWII was inversely associated with Warburg‐low colon cancer, whereas energy restriction during the Economic Depression was positively associated with Warburg‐high colon cancer. Adolescent BMI was positively associated with Warburg‐high colon cancer in men, and Warburg‐moderate rectal cancer in women. In conclusion, the Warburg‐effect seems to be involved in associations of adolescent BMI with colon cancer in men, and of energy restriction during the Economic Depression with colon cancer in women. Further research is needed to validate these results.

Cross-Sectional Associations between Dietary Daily Nicotinamide Intake and Patient-Reported Outcomes in Colorectal Cancer Survivors, 2 to 10 Years Post-Diagnosis

Supplementation with nicotinamide adenine dinucleotide (NAD⁺) precursors including dietary nicotinamide has been found to boost tissue NAD⁺ levels and ameliorate oxidative stress-induced damage that contributes to aging and aging-related diseases. The association between dietary NAD⁺ precursors and patient-reported health-related outcomes in cancer survivors has not been investigated. This study aimed to determine associations of dietary nicotinamide intake with different patient-reported outcomes in colorectal cancer survivors, 2 to 10 years post-diagnosis. A total of 145 eligible participants were recruited into this cross-sectional study. Dietary nicotinamide intake level was calculated based on data from 7-day food diaries. Fatigue was assessed with the Checklist Individual Strength (CIS), which is a subscale of the cancer-specific European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC), and anxiety and depression were assessed with Hospital Anxiety and Depression Scale (HADS). Oxidative stress marker serum protein carbonyl contents and serum NAD⁺ levels were measured. A hierarchical linear regression model with confounder adjustment was performed to analyze the association of nicotinamide intake, serum protein carbonyl contents, and NAD⁺ levels with patient-reported outcomes. The median values of daily nicotinamide intake for male and female participants were 19.1 and 14.4 mg, respectively. Daily dietary nicotinamide intake was associated with a lower level of fatigue (β: -14.85 (-28.14, -1.56)) and a lower level of anxiety and depression (β: -4.69 (-8.55, -0.83)). Subgroup analyses by sex showed that a beneficial association between nicotinamide intake and patient-reported outcomes was mainly found in men. To conclude, our findings suggested that higher dietary NAD⁺ precursor nicotinamide intake was cross-sectionally associated with less patient-reported outcomes in CRC survivors.

Eating disorders and the risk of developing cancer: a systematic review

PURPOSE

Evidence concerning eating disorders as risk toward developing cancer is sparse. Energy restriction might be cancer protective, while malnutrition, vomiting, laxative and substance use might stimulate cancer development. We examined whether individuals with an eating disorder (not restricted to anorexia nervosa) had a different risk of developing cancer.

METHODS

A systematic search on Medline and Embase until 28th April 2020 identified relevant human original research publications, including all populations and all cancer types.

RESULTS

From 990 records, 6 case reports and 9 cohorts were included. Some cohorts found a decreased breast (3/5 studies) or cervical (1/2) cancer risk, while an increased esophageal (2/3), liver (1/1), brain (1/1 in men) and respiratory (2/4) cancer risk, but other cancer risks were non-significant, and an increased mortality overall (1/2), from breast (1/1), female genital (1/1) and skin (1/1) cancer in eating disorder patients. The case reports further described esophageal cancer and leukemia. No clear statistical differences in cancer risk were found depending on eating disorder type, perhaps due to the small sample size (n = 1783 for other than anorexia nervosa).

CONCLUSIONS

The literature on eating disorders and cancer risk is sparse with many gaps. Hormonal changes, sexual activity, nutritional status, vomiting and concomitant tobacco/alcohol abuse may explain increased/decreased cancer risk. Future large studies (now 1-366 cancer cases) that also include men (now 4.7%), bulimia nervosa (now 3.8%) and several cancer sites (now mainly breast cancer) are needed and should foresee longer follow-up time (now 5.4-15.2 years) and extensive confounder adjustment (now only age and sex).

LEVEL OF EVIDENCE

Level I, systematic review.

Association of Prostate Cancer with Nuts, Seeds, Alcohol and Processed Meats: A Worldwide Population-Based Study

There are conflicting data with regards to the link between diet and the prostate cancer. The purpose of this study was to assess the association of dietary factors with incidence, prevalence and mortality rates of prostate cancer worldwide. We conducted an ecological study including 170 countries, whose data on incidence, prevalence and mortality rates of prostate cancer, dietary factors, and potentially confounding factors were available and collected in May 2020. Univariable and multivariable linear regression analyses were used. Consumption of nuts and seeds was inversely associated with incidence, prevalence and mortality rates of prostate cancer (β -0.7, P < 0.001; β -2.1, P < 0.001; β -0.1, P = 0.02; respectively). Intake of alcohol was associated with increased incidence, prevalence and mortality rates of prostate cancer (β 1.8, P < 0.001; β 4.5, P < 0.001; β 0.4, P < 0.001; respectively). Consumption of processed meats was also associated with increased incidence and prevalence rates of prostate cancer (β 0.6, P = 0.003; β 2.8, P = 0.001; respectively). These data suggest that consumption of nuts and seeds have a protective effect against prostate carcinogenesis, progression, and metastasis, while alcohol and processed meat increase these risks.

Overeating, caloric restriction and breast cancer risk by pathologic subtype: the EPIGEICAM study

This study analyzes the association of excessive energy intake and caloric restriction with breast cancer (BC) risk taking into account the individual energy needs of Spanish women. We conducted a multicenter matched case-control study where 973 pairs completed lifestyle and food frequency questionnaires. Expected caloric intake was predicted from a linear regression model in controls, including calories consumed as dependent variable, basal metabolic rate as an offset and physical activity as explanatory. Overeating and caloric restriction were defined taking into account the 99% confidence interval of the predicted value. The association with BC risk, overall and by pathologic subtype, was evaluated using conditional and multinomial logistic regression models. While premenopausal women that consumed few calories (>20% below predicted) had lower BC risk (OR = 0.36; 95% CI = 0.21–0.63), postmenopausal women with an excessive intake (≥40% above predicted) showed an increased risk (OR = 2.81; 95% CI = 1.65–4.79). For every 20% increase in relative (observed/predicted) caloric intake the risk of hormone receptor positive (p-trend < 0.001) and HER2+ (p-trend = 0.015) tumours increased 13%, being this figure 7% for triple negative tumours. While high energy intake increases BC risk, caloric restriction could be protective. Moderate caloric restriction, in combination with regular physical activity, could be a good strategy for BC prevention.

Associations of adult-attained height and early life energy restriction with postmenopausal breast cancer risk according to estrogen and progesterone receptor status

Adult-attained height is a marker for underlying mechanisms, such as cell growth, that may also influence postmenopausal breast cancer (BC) risk, perhaps specifically hormone-sensitive BC subtypes. Early life energy restriction may inhibit these mechanisms, resulting in shorter height and a reduced postmenopausal BC risk. Women (62,573) from the Netherlands Cohort Study completed a self-administered questionnaire in 1986 when 55-69 years old, and were followed-up for 20.3 years (case-cohort: N_subcohort = 2,438; N_cases = 3,354). Cox multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) were estimated for BC risk overall and by estrogen and progesterone receptor subtypes in relation to height and early life energy restriction during the Hunger Winter, War Years, and Economic Depression. Although energy restriction can only influence longitudinal growth in women exposed before and/or during the growth spurt, it may also influence BC risk when occurring after the growth spurt, possibly through different growth processes. Therefore, Cox analyses were additionally conducted according to timing of energy restriction in relation to the growth spurt. Height was associated with an increased BC risk (HR_{per 5cm} = 1.07, 95%CI:1.01-1.13), particularly hormone receptor-positive BC. Energy restriction before and/or during the growth spurt was associated with a decreased hormone receptor-positive BC risk. Energy restriction during the Hunger Winter increased the estrogen receptor-negative BC risk regardless of the timing of energy restriction. In conclusion, height and energy restriction before and/or during the growth spurt were both associated with hormone receptor-positive BC risk, in the direction as expected, indicating critical exposure windows for hormonal growth-related mechanisms.

Energy restriction at young age, genetic variants in the insulin-like growth factor pathway and colorectal cancer risk in the Netherlands Cohort Study

The energy restriction (ER)-colorectal cancer (CRC) association is inconsistent in literature. To strengthen the biological plausibility of the ER-CRC association, we investigated whether genetic variation in the insulin-like growth factor (IGF) pathway, a putative underlying mechanism, modulated this association in the Netherlands Cohort Study. Participants completed a questionnaire (n = 120,852) and provided toenail clippings for DNA (∼75%) at baseline. Individuals living in a Western city during the Hunger Winter (1944-45) or Western rural versus non-Western area were exposed to (severe) ER at young age. Genotyping was performed for 3,768 subcohort members and 2,580 CRC cases (case-cohort with 16.3 years follow-up). Cox hazard ratios for CRC were estimated across combined categories of ER and a genetic sum score of unfavorable alleles based on 18 single nucleotide polymorphisms in IGF-related genes and ER and an IGF1 19-CA repeat polymorphism. The reference included ER exposed individuals, so that increased hazard ratios were expected in higher combined categories for calculating relative excess risks due to interaction (additive interactions). Wald tests for multiplicative interactions were also performed. Multiplicative and additive interactions were nonsignificant. Combined ER-genetic sum score categories showed increasing CRC risks in men, but confidence intervals were wide. Women carrying two variant IGF1 19-CA repeat alleles versus those carrying two wild type IGF1 19-CA repeat alleles were at an ∼50% decreased CRC risk, irrespective of ER exposure. In conclusion, data indicate that the IGF pathway might be involved in the ER-CRC association in men, but not women, although interactions were nonsignificant, hampering definite conclusions.