Medical Bulletin 17/ May/ 2024

In a recent study published in Gastric Cancer, researchers found that individuals who always add salt to food were at a higher risk for gastric cancer than individuals who rarely or never added salt.

Gastric cancer — also known as stomach cancer — is the fifth most common cancer in the world. Many factors contribute to the risk for gastric cancer, including smoking, increased age, obesity, and family history.

Previous studies have indicated that regular consumption of salt is associated with an increased risk of gastric cancer. The high sodium content in table salt has been linked to the development of gastric cancer due to its potential to damage the lining of the stomach and promote inflammation.Excessive salt intake can lead to the formation of carcinogenic compounds in the stomach, increasing the risk of cancerous growths.

In the study, researchers utilized data from the UK Biobank, incorporating 471,144 participants in their analysis. These participants completed baseline questionnaires detailing their frequency of adding salt to food, excluding salt used during cooking. Additionally, researchers measured urinary sodium, creatinine, and potassium levels to estimate 24-hour urinary sodium excretion. Covariates such as physical activity levels, age, alcohol use, red meat consumption, and fruit and vegetable intake were accounted for in the analysis. The median follow-up period with participants lasted 10.9 years.

The study found that during the follow-up period, 640 cases of gastric cancer were documented among participants. Researchers observed that individuals who consistently added salt to food faced a 41% higher risk of gastric cancer compared to those who seldom or never did so. While there was an association between more frequent salt addition and increased 24-hour urinary sodium levels, researchers did not find a significant link between 24-hour urinary sodium levels and gastric cancer.

The findings suggested that examining the frequency of added salt use at the table may be a simple way to assist in identifying individuals with high salt intake who may, in turn, be at risk for gastric cancer.

“Excessive salt intake has long been linked to hypertension and cardiovascular disease. Now, emerging evidence from this study suggests that routine consumption of salt with meals may also heighten the risk of developing gastric cancer. Given the well-established health risks associated with salt, it's crucial for people to recognize and limit their intake to mitigate potential harm,” said Anton Bilchik, chief of medicine, and Director of the Gastrointestinal and Hepatobiliary Program at Providence Saint John’s Cancer Institute.

Reference: Kronsteiner-Gicevic, S., Thompson, A.S., Gaggl, M. et al. Adding salt to food at table as an indicator of gastric cancer risk among adults: a prospective study. Gastric Cancer (2024). https://doi.org/10.1007/s10120-024-01502-9

According to a study published in the journal PLoS ONE, vegetarian and vegan diets have been linked to improved cardiovascular health and reduced cancer risk, along with lower incidences of cardiovascular diseases and cancer.

Previous research has found a connection between specific dietary patterns and elevated risks of cardiovascular disease and cancer. Diets characterized by low intake of plant-based foods and high consumption of meat, refined grains, sugar, and salt have been associated with increased mortality rates.

To mitigate these risks, recommendations have been made to reduce the consumption of animal-derived products in favour of plant-based alternatives, with the aim of lowering the incidence of cardiovascular disease and cancer. Nevertheless, the comprehensive benefits of adopting such dietary changes remain uncertain.

In the study, researchers conducted a comprehensive review of 48 papers published between January 2000 and June 2023. These papers had compiled evidence from various prior studies. Employing an "umbrella" review methodology, the researchers extracted and analyzed data from the 48 papers to investigate the associations between plant-based diets, cardiovascular health, and cancer risk.

The analysis revealed that vegetarian and vegan diets are strongly linked to improved health indicators related to cardiometabolic diseases, cancer, and mortality. These diets are associated with lower blood pressure, better blood sugar management, and healthier body mass index. Moreover, they are linked to decreased risk of ischemic heart disease, gastrointestinal and prostate cancer, as well as reduced cardiovascular disease mortality.

These findings indicated that plant-based diets offer notable health advantages. However, researchers caution that the strength of this association is substantially constrained due to variations including differences in diet types, participant characteristics, study durations, and other variables. Additionally, certain plant-based diets may lead to vitamin and mineral deficiencies in certain individuals.

“Our study evaluates the different impacts of animal-free diets for cardiovascular health and cancer risk showing how a vegetarian diet can be beneficial to human health and be one of the effective preventive strategies for the two most impactful chronic diseases on human health in the 21st century,” said the authors.

Reference: Angelo Capodici, Gabriele Mocciaro, Davide Gori, et al.; Cardiovascular health and cancer risk associated with plant based diets: An umbrella review; PLoS ONE; https://doi.org/10.1371/journal.pone.0300711

A study conducted by Rutgers Health experts analysing over 31 million hospital records indicated that individuals undergoing infertility treatment were twice as likely to be hospitalised for heart disease in the year following delivery compared to those who conceived naturally.

The study, published in the Journal of Internal Medicine, found that patients who underwent infertility were particularly likely — 2.16 times as likely as those who conceived naturally — to undergo hospitalisation for dangerously high blood pressure or hypertension.

Cardiovascular disease is a major cause of maternal mortality, contributing to an increased number of maternal deaths over the years and now accounting for 26% of pregnancy-related deaths.

Infertility treatment is becoming more prevalent as a means to attain pregnancy, with approximately 12.2% of women of reproductive age seeking such services between 2015 and 2019. Assisted reproductive technology accounted for about 2% of births in 2018. However, alongside its increasing use, infertility treatment has been associated with adverse outcomes for both mothers and newborns. These include heightened risks of hypertensive disorders of pregnancy and gestational diabetes.

Previous study has found that women who delivered after in vitro fertilization (IVF) reported a higher rate of hypertension and more incident strokes compared with those who delivered after spontaneous conception.

In the study, researchers utilized the Nationwide Readmissions Database and included 287,813 patients who had undergone various forms of infertility treatment.

The analysis revealed that infertility treatment significantly predicted a markedly increased risk of heart disease. Specifically, among women who received infertility treatment, 550 out of every 100,000 were hospitalized with cardiovascular disease in the year following delivery. In contrast, among those who conceived naturally, the rate was lower, with 355 out of every 100,000 women hospitalized with cardiovascular disease.

“Postpartum checkups are crucial for all patients, especially those who undergo infertility treatment to conceive, as highlighted by this study. Early follow-up care is essential, as indicated by a series of studies revealing serious risks of heart disease and stroke within the initial 30 days after delivery. However, the exact cause of the elevated risk of heart disease associated with infertility treatment remains unclear. It could be attributed to the treatments themselves, underlying medical conditions contributing to infertility, or other factors” said the study authors.

Reference: Rei Yamada, Devika Sachdev, Rachel Lee, Mark V. Sauer, Cande V. Ananth; Infertility treatment is associated with increased risk of postpartum hospitalization due to heart disease; Journal of Internal Medicine; https://doi.org/10.1111/joim.13773