Frequent salting of food increases the risk of stomach cancer

 

Connection between salt consumption and stomach cancer shown for the first time in Western countries

In Asian countries, where high-salt foods are popular, the link between high salt consumption and stomach cancer has already been proven. A long-term study by MedUni Vienna has now shown for the first time that this risk is also reflected in the cancer statistics in Europe. As the analysis recently published in the specialist journal Gastric Cancer shows, people who frequently add salt to their food are around 40 per cent more likely to develop stomach cancer than those who do not use the salt shaker at the table.

Data from more than 470,000 adults from the large-scale British cohort study "UK-Biobank" was analysed. Among other things, the answers to the question: "How often do you add salt to your food?" were collected by questionnaire between 2006 and 2010. The research team led by Selma Kronsteiner-Gicevic and Tilman Kühn from MedUni Vienna's Center for Public Health compared the results of the survey with salt excretion in urine and with data from national cancer registries. This revealed that people who said they always or frequently added salt to their food were 39 per cent more likely to develop stomach cancer over an observation period of around 11 years than those who never or rarely added an extra pinch of salt to their food. "Our results also stood up to the consideration of demographic, socioeconomic and lifestyle factors and were just as valid for prevailing comorbidities," says first author Selma Kronsteiner-Gicevic, emphasising the significance of the results.

Stomach cancer is affecting more and more younger people
In the list of the most common types of cancer worldwide, stomach cancer is in fifth place. The risk of this tumour disease increases with age, but the latest statistics paint a worrying picture of an increase in adults under the age of 50. Risk factors include tobacco and alcohol consumption, an infection with Helicobacter pylori, overweight and obesity. The fact that a very salty diet increases the risk of stomach cancer has previously been proven in studies with Asian population groups, who frequently eat food preserved in salt, heavily salted fish or extremely salty marinades and sauces.

"Our research shows the connection between the frequency of added salt and stomach cancer in Western countries too," emphasises first author Selma Kronsteiner-Gicevic. "With our study, we want to raise awareness of the negative effects of extremely high salt consumption and provide a basis for measures to prevent stomach cancer," summarises study leader Tilman Kühn.

Neuropathy very common, underdiagnosed

 

 Neuropathy, the nerve damage that causes pain and numbness in the feet and hands and can eventually lead to falls, infection and even amputation, is very common and underdiagnosed, according to a study published in the May 8, 2024, online issue of Neurology®, the medical journal of the American Academy of Neurology.

“More than one-third of people with neuropathy experience sharp, prickling or shock-like pain, which increases their rates of depression and decreases quality of life,” said study author Melissa A. Elafros, MD, PhD, of the University of Michigan in Ann Arbor and a member of the American Academy of Neurology. “People with neuropathy also have an increased risk of earlier death, even when you take into account other conditions they have, so identifying and treating people with or at risk for neuropathy is essential.”

The study involved 169 people from an outpatient internal medicine clinic serving mainly Medicaid patients in Flint, Michigan. The participants had an average age of 58 years and 69% were Black people. One-half of the people had diabetes, which can cause neuropathy. A total of 67% had metabolic syndrome, which is defined as having excess belly fat plus two or more of the following risk factors: high blood pressure, higher than normal triglycerides (a type of fat found in the blood), high blood sugar and low high-density lipoprotein (HDL) cholesterol, or “good” cholesterol. These risk factors are also associated with neuropathy.

All participants were tested for distal symmetric polyneuropathy. Information about other health conditions was also collected.

A total of 73% of the people had neuropathy. Of those, 75% had not been previously diagnosed with the condition. Nearly 60% of those with neuropathy were experiencing pain.

Of those with neuropathy, 74% had metabolic syndrome, compared to 54% of those who did not have neuropathy.

After adjusting for other factors that could affect the risk of neuropathy, researchers found that people with metabolic syndrome were more than four times more likely to have neuropathy than people who did not have the syndrome.

Researchers were also looking for any relationship between race and income and neuropathy, as few studies have been done on those topics. There was no relationship between low income and neuropathy. For race, Black people had a decreased risk of neuropathy. Black people made up 60% of those with neuropathy and 91% of those without neuropathy.

“The amount of people with neuropathy in this study, particularly undiagnosed neuropathy, was extraordinarily high with almost three fourths of the study population,” Elafros said. “This highlights the urgent need for interventions that improve diagnosis and management of this condition, as well as the need for managing risk factors that can lead to this condition.”
A limitation of the study is that it is a snapshot in time; it did not follow people to see who developed neuropathy over time. It also did not look at reasons why people were not able to manage risk factors that can lead to neuropathy.

The study was supported by the National Institute of Neurological Disorders and Stroke, National Institute of Diabetes and Digestive and Kidney Diseases and National Center for Advancing Translational Sciences.

Learn more about neuropathy at BrainandLife.org, home of the American Academy of Neurology’s free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow Brain & Life® on Facebook, X and Instagram.

30-year US study links ultra-processed food to higher risk of early death

 

Not all ultra-processed foods should be universally restricted, but findings support limiting certain types for long term health

Peer-Reviewed Publication

BMJ

Higher consumption of most ultra-processed foods is linked to a slightly higher risk of death, with ready-to-eat meat, poultry, and seafood based products, sugary drinks, dairy based desserts, and highly processed breakfast foods showing the strongest associations, finds a 30-year US study in The BMJ today.

The researchers say not all ultra-processed food products should be universally restricted, but that their findings “provide support for limiting consumption of certain types of ultra-processed food for long term health.”

Ultra-processed foods include packaged baked goods and snacks, fizzy drinks, sugary cereals, and ready-to-eat or heat products. They often contain colours, emulsifiers, flavours, and other additives and are typically high in energy, added sugar, saturated fat, and salt, but lack vitamins and fibre.

Mounting evidence links ultra-processed foods to higher risks of obesity, heart disease, diabetes and bowel cancer, but few long term studies have examined links to all cause and cause specific deaths, especially due to cancer.

To address this knowledge gap, researchers tracked the long-term health of 74,563 female registered nurses from 11 US states in the Nurses’ Health Study (1984-2018) and 39,501 male health professionals from all 50 US states in the Health Professionals Follow-up Study (1986-2018) with no history of cancer, cardiovascular diseases, or diabetes at study enrolment.

Every two years participants provided information on their health and lifestyle habits, and every four years they completed a detailed food questionnaire. Overall dietary quality was also assessed using the Alternative Healthy Eating Index-2010 (AHEI) score.

During an average 34-year follow-up period, the researchers identified 48,193 deaths, including 13,557 deaths due to cancer, 11,416 deaths due to cardiovascular diseases, 3926 deaths due to respiratory diseases, and 6343 deaths due to neurodegenerative diseases.

Compared with participants in the lowest quarter of ultra-processed food intake (average 3 servings per day), those in the highest quarter (average 7 servings per day) had a 4% higher risk of total deaths and a 9% higher risk of other deaths, including an 8% higher risk of neurodegenerative deaths.

No associations were found for deaths due to cardiovascular diseases, cancer, or respiratory diseases.

In absolute numbers, the rate of death from any cause among participants in the lowest and highest quarter of ultra-processed food intake was 1472 and 1536 per 100,000 person years, respectively.

The association between ultra-processed food intake and death varied across specific food groups, with meat, poultry, and seafood based ready-to-eat products showing the strongest and most consistent associations, followed by sugar sweetened and artificially sweetened beverages, dairy based desserts, and ultra-processed breakfast food. 

And the association was less pronounced after overall dietary quality was taken into account, suggesting that dietary quality has a stronger influence on long term health than ultra-processed food consumption, note the authors.

This is an observational study, so no firm conclusions can be drawn about cause and effect, and the authors point out that the ultra-processed food classification system does not capture the full complexity of food processing, leading to potential misclassification. In addition, participants were health professionals and predominantly white, limiting the generalizability of the findings.

However, this was a large study with long follow-up, using detailed, validated, and repeated measurements, and results were similar after further analyses, providing greater confidence in the conclusions.

The researchers stress that not all ultra-processed food products should be universally restricted and say oversimplification when formulating dietary recommendations should be avoided. 

But they conclude: “The findings provide support for limiting consumption of certain types of ultra-processed food for long term health,” adding that “future studies are warranted to improve the classification of ultra-processed foods and confirm our findings in other populations.”

In a linked editorial, researchers in New Zealand point out that recommendations to avoid ultra-processed food may also give the impression that foods that are not ultra-processed, such as red meat, can be frequently consumed.

They argue that debate about the ultra-processed concept must not delay food policies that improve health, such as restrictions on marketing unhealthy foods to children, warning labels on nutritionally poor food products, and taxes on sugary drinks.

“Our focus should be on advocating for greater global adoption of these and more ambitious interventions and increasing safeguards to prevent policies from being influenced by multinational food companies with vested interests that do not align with public health or environmental goals,” they conclude.

U.S. health impacts from gas stoves

 

People with gas and propane stoves breathe more unhealthy nitrogen dioxide

Peer-Reviewed Publication

STANFORD UNIVERSITY

 

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STANFORD PHD STUDENT METTA NICHOLSON OBSERVES A GAS BURNER IN A HOME WHERE SCIENTISTS MEASURED AIR POLLUTION AS PART OF THEIR DATA COLLECTION IN CALIFORNIA, TEXAS, COLORADO, NEW YORK, AND WASHINGTON, D.C..

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CREDIT: ROB JACKSON, STANFORD DOERR SCHOOL OF SUSTAINABILITY

Households with gas or propane stoves regularly breathe unhealthy levels of nitrogen dioxide, a study of air pollution in U.S. homes found.

“I didn’t expect to see pollutant concentrations breach health benchmarks in bedrooms within an hour of gas stove use, and stay there for hours after the stove is turned off,” said Stanford Doerr School of Sustainability Professor Rob Jackson, senior author of the May 3 study in Science Advances. Pollution from gas and propane stoves isn’t just an issue for cooks or people in the kitchen, he said. “It’s the whole family’s problem.”

Among other negative health effects, breathing high levels of nitrogen dioxide, or NO2, over time can intensify asthma attacks and has been linked to decreased lung development in children and early deaths.

Although most exposure to NO2 is caused by cars and trucks burning fossil fuels, the researchers estimate that the mix of pollutants coming from gas and propane stoves overall may be responsible for as many as 200,000 current childhood asthma cases. One quarter of these can be attributed to nitrogen dioxide alone, according to the paper’s authors, who include scientists from Central California Asthma Collaborative, PSE Healthy Energy, and the Harvard T.H. Chan School of Public Health.

“We found that just how much gas you burn in your stove is by far the biggest factor affecting how much you’re exposed. And then, after that, do you have an effective range hood – and do you use it?” said lead study author Yannai Kashtan, a PhD student in Earth system science.

Little room for additional exposure

Beyond asthma cases, the long-term exposure to NO2 in American households with gas stoves is high enough to cause thousands of deaths each year – possibly as many as 19,000 or 40% of the number of deaths linked annually to secondhand smoke. This estimate is based on the researchers’ new measurements and calculations of how much nitrogen dioxide people breathe at home because of gas stoves and the best available data on deaths from long-term exposure to outdoor NO2, which is regulated by the U.S. Environmental Protection Agency.

The death toll estimate is approximate in part because it does not factor in the harmful effects of repeated exposure to extremely high levels of nitrogen dioxide in short bursts, as occurs in homes with gas stoves. It also relies on past studies of health impacts from nitrogen dioxide encountered outdoors, where additional pollutants from vehicles and power plants are present.

The researchers used sensors to measure concentrations of NO2 throughout more than 100 homes of various sizes, layouts, and ventilation methods, before, during, and after stove use. They incorporated these measurements and other data into a model powered by National Institutes for Standards and Technology (NIST) software known as CONTAM for simulating airflow, contaminant transport, and room-by-room occupant exposure in buildings. This allowed them to estimate nationwide averages and short-term exposures under a range of realistic conditions and behaviors, and cross-check model outputs against their home measurements.

The results show that nationwide, typical use of a gas or propane stove increases exposure to nitrogen dioxide by an estimated 4 parts per billion, averaged over a year. That’s three quarters of the way to the nitrogen dioxide exposure level that the World Health Organization recognizes as unsafe in outdoor air. “That’s excluding all outdoor sources combined, so it makes it much more likely you’re going to exceed the limit,” said Kashtan.

Understanding how gas stoves affect health

The study is the latest in a series from Jackson’s group at Stanford looking at indoor air pollution from gas stoves. Earlier studies documented the rate at which gas stoves emit other pollutants, including the greenhouse gas methane and the carcinogen benzene. But to understand the implications of stove emissions for human health, the researchers needed to find out how much pollutants spread through a home, build up, and eventually dissipate. “We’re moving from measuring how much pollution comes from stoves to how much pollution people actually breathe,” said Jackson, who is the Michelle and Kevin Douglas Provostial Professor in Earth System Science.

With any fuel source, particle pollution can rise from food cooking in a hot pan. The new research confirms that food emits little or no nitrogen dioxide as it cooks, however, and electric stoves produce no NO2. “It’s the fuel, not the food,” said Jackson. “Electric stoves emit no nitrogen dioxide or benzene. If you own a gas or propane stove, you need to reduce pollutant exposures using ventilation.”

Home size matters

Even in larger homes, concentrations of nitrogen dioxide routinely spiked to unhealthy levels during and after cooking even if a range hood was on and venting air outdoors. But people who live in homes smaller than 800 square feet – about the size of a small two-bedroom apartment – are exposed to twice as much nitrogen dioxide over the course of a year compared to the national average, and four times more compared to those living in the largest homes, upwards of 3,000 square feet.

Because home size makes such a difference, there are also differences in exposure across racial, ethnic, and income groups. Compared to the national average, the researchers found long-term NO2 exposure is 60% higher among American Indian and Alaska Native households, and 20% higher among Black and Hispanic or Latino households. This exposure to indoor air pollution from gas stoves compounds the fact that exposure to outdoor sources of nitrogen dioxide pollution, such as vehicle exhaust, is also typically higher among people in poorer, often minority, communities.

“People in poorer communities can’t always afford to change their appliances, or perhaps they rent and can’t replace appliances because they don’t own them,” Jackson said. “People in smaller homes are also breathing more pollution for the same stove use.”

 

Stay active – or get active – to boost quality of life while aging

 

Peer-Reviewed Publication

PLOS

 

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RESEARCHERS ASSESS PHYSICAL HEALTH AND WOMEN’S ACTIVITY LEVELS IN MID-AGE AND LATER LIFE.

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CREDIT: PIXABAY, PEXELS (CC0, HTTPS://CREATIVECOMMONS.ORG/PUBLICDOMAIN/ZERO/1.0/DEED)

Consistent adherence to physical activity guidelines throughout middle-age is associated with a higher health-related quality of life in women, according to a new study publishing May 2nd in the open-access journal PLOS Medicine by Binh Nguyen of University of Sydney, Australia, and colleagues.

The evidence for an association between physical activity and health-related quality of life has been based primarily on cross-sectional studies and short-term randomized controlled trials. Few longitudinal studies have measured physical activity at more than one time point and examined the long-term causal effects of exercise.

In the new study, researchers used data collected at three-year intervals beginning in 1996 from 11,336 participants in the Australian Longitudinal Study on Women’s Health. Women were born in 1946 through 1951, making them 47 to 52 years old at the study outset. Participants were classified as either meeting WHO physical activity guidelines — of 150 minutes of activity a week — consistently throughout the fifteen-year exposure period, not initially meeting the guidelines but starting to meet them at age 55, 60 or 65, or never meeting the guidelines. Health-related quality of life was assessed using the physical health composite score (PCS) and mental health composite score (MCS) from the Short Form 36 Health Survey, which includes 36 questions about functional health and well-being.

On average, people who consistently met physical activity guidelines and those who first started to meet guidelines at age 55 had a three-point higher PCS (46.93 [95% CI 46.32 to 47.54] and 46.96 [95% CI 45.53 to 48.40], respectively), compared to those that did not meet physical activity guidelines (43.90 [95% CI 42.79 to 45.01]). The effect of physical activity on the PSC was significant even after controlling for socioeconomic factors and pre-existing health diagnoses. However, there was no significant association between physical activity and MCS.

“Combined with existing evidence, this study contributes to growing evidence of the benefits of maintaining or adopting an active lifestyle in mid-age,” the authors say. “An important public health message is that being active for as many years as possible, even if women start to meet physical activity guidelines in their mid-50s, could have important health benefits in terms of physical health, especially in physical functioning.”

The authors add, “Our study shows that it’s important for women to be active throughout mid-age to gain the most benefits for physical health in later life. Ideally, women should increase their activity levels to meet the guidelines by age 55.”

The freely available paper in PLOS Medicine: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1004384

Time-restricted eating and high-intensity exercise might work together to improve health

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Peer-Reviewed Publication

PLOS

 

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STUDY DESIGN.

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CREDIT: AMEUR ET AL., 2024, PLOS ONE, CC-BY 4.0 (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

Combining time-restricted eating with high-intensity functional training may improve body composition and cardiometabolic parameters more than either alone, according to a study published May 1, 2024 in the open-access journal PLOS ONE by Ranya Ameur and Rami Maaloul from the University of Sfax, Tunisia, and colleagues.

Changes in diet and exercise are well-known ways to lose weight and improve cardiometabolic health. However, finding the right combination of lifestyle changes to produce sustainable results can be challenging. Prior studies indicate that time-restricted eating (which limits when, but not what, individuals eat) and high-intensity functional training (which combines intense aerobic and resistance exercise) may be beneficial and easier for individuals to commit to long term.

In a new study, researchers investigated the impact of time-restricted eating and high-intensity functional training on body composition and markers of cardiometabolic health such as cholesterol, blood glucose, and lipid levels. 64 women with obesity were assigned to one of three groups: time-restricted eating (diet only), high-intensity functional training (exercise only), or time-restricted eating plus high-intensity functional training (diet + exercise). Participants following the time-restricted eating regimen ate only between 8:00 am and 4:00 pm. Those in the functional training groups worked out three days per week with an instructor.

After 12 weeks, all three groups had significant weight loss and decreases in waist and hip circumference. Likewise, all groups showed favorable changes in lipid and glucose levels.

Some differences were seen between groups. For example, fat-free mass (a combination of lean mass and skeletal muscle mass) and blood pressure improved in the diet + exercise and exercise groups but did not change in the diet-only group.

Participants in the diet + exercise group generally experienced more profound changes in body composition and cardiometabolic parameters than either diet or exercise alone.

The researchers noted that this is a relatively small study, and it is difficult to tease out the contributions of specific exercise routines or of time-restricted eating and calorie reduction since both groups reduced their calorie intake. However, they note that combining time-restricted eating with high-intensity functional training might show promise in improving body composition and cardiometabolic health.

The authors add: “Combining time-restricted eating with High Intensity Functional Training is a promising strategy to improve body composition and cardiometabolic health.

The freely available article in PLOS ONE: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0301369

Psilocybin’s potential as an antidepressant

Psilocybin - the active ingredient in “magic” mushrooms - is a more effective treatment for symptoms of depression than controls, providing further support for its potential as an antidepressant, suggests a study published by The BMJ today.

The researchers say the findings are encouraging but “further research is needed to clarify the factors that maximise psilocybin’s treatment potential for symptoms of depression.”

Depression affects an estimated 300 million people worldwide and is a leading cause of disability.

Psilocybin has shown promise in reducing symptoms of depression after one or two doses with few side effects and no current evidence of causing addiction. However, studies published to date have not investigated factors that may moderate psilocybin’s effects, including type of depression, past use of psychedelics, dosage, and publication biases.

To address this, a team of UK researchers examined databases looking for randomised controlled trials that compared psilocybin as a treatment for symptoms of depression with controls, such as placebo, niacin (vitamin B), or micro doses of psychedelics.

They included studies where psychotherapy was present in both the experimental and the control conditions, so that the effects of psilocybin could be distinguished from those of psychotherapy.

They found seven relevant trials for analysis involving 436 participants with depression (52% female; 90% white). Changes in depression scores were measured using a statistical method called Hedges’ g. A Hedges’ g of 0.2 indicates a small effect, 0.5 a moderate effect, and 0.8 or more a large effect.

The change in depression scores was significantly greater after treatment with psilocybin than with a comparator treatment, with an overall Hedge’s g of 1.64 indicating a large effect size favouring psilocybin.

Further analyses to account for trial differences indicated that having secondary depression (related to an underlying disease) rather than primary depression, being assessed with a self-reported scale rather than a clinician assessed scale, older age, and previous use of psychedelics, were correlated with greater improvements.

The study authors acknowledge that high levels of variation (heterogeneity) between trials resulted in a low certainty of evidence to support a strong antidepressant effect of psilocybin, and generalisability of findings were limited by the lack of participant diversity. 

Pre-treatment expectations and the extent to which participants knew they were being treated with psilocybin or placebo, were also not measured.

Furthermore, in clinical trials, patients receive psilocybin in a calm living room with soothing music, supervised by a psychotherapist, which is unlikely to be achievable in a healthcare system. 

As such, the authors conclude that, although this review’s findings are encouraging for psilocybin’s potential as an effective antidepressant, issues such as cost, lack of regulatory guidelines and legal safeguards associated with psilocybin treatment need to be dealt with before it can be established in clinical practice.

This study is an important contribution to the evidence base for the use of psilocybin in depression, but it cannot answer several questions, say researchers unconnected to the study in a linked editorial.

For instance, they argue that it cannot provide evidence for psilocybin’s effectiveness (performance under 'real-world' conditions) in depression until more information about potential effect modifiers is gathered, and that pragmatic clinical trials and real world data could help to deliver that.

Furthermore, there is still ongoing debate on whether psychedelics can express antidepressant activity on their own rather than by assisting specific forms of psychotherapy. 

Finally, and perhaps most importantly, the editorial authors say that, as per all analyses using aggregate data, we cannot differentiate between those individuals most likely to benefit from psilocybin and those who might instead experience adverse events.

As such, they conclude that these promising findings “support a prudent approach in both scholarly and public settings, because more and better evidence is needed before any clinical recommendation can be made about therapeutic use of psilocybin.”