Ultra-processed foods may be linked to increased risk of cancer

Higher consumption of ultra-processed foods may be linked to an increased risk of developing and dying from cancer, an Imperial College London-led observational study suggests.

Researchers from Imperial’s School of Public Health have produced the most comprehensive assessment to date of the association between ultra-processed foods and the risk of developing cancers. Ultra-processed foods are food items which have been heavily processed during their production, such as fizzy drinks, mass-produced packaged breads, many ready meals and most breakfast cereals.

Ultra-processed foods are often relatively cheap, convenient, and heavily marketed, often as healthy options. But these foods are also generally higher in salt, fat, sugar, and contain artificial additives. It is now well documented that they are linked with a range of poor health outcomes including obesity, type 2 diabetes and cardiovascular disease.

The first UK study of its kind used UK Biobank records to collect information on the diets of 200,000 middle-aged adult participants. Researchers monitored participants’ health over a 10-year period, looking at the risk of developing any cancer overall as well as the specific risk of developing 34 types of cancer. They also looked at the risk of people dying from cancer.

The study found that higher consumption of ultra-processed foods was associated with a greater risk of developing cancer overall, and specifically with ovarian and brain cancers. It was also associated with an increased risk of dying from cancer, most notably with ovarian and breast cancers.

For every 10 per cent increase in ultra-processed food in a person’s diet, there was an increased incidence of 2 per cent for cancer overall, and a 19 per cent increase for ovarian cancer specifically.

Each 10 per cent increase in ultra-processed food consumption was also associated with increased mortality for cancer overall by 6 per cent, alongside a 16 per cent increase for breast cancer and a 30 per cent increase for ovarian cancer.

These links remained after adjusting for a range of socio-economic, behavioural and dietary factors, such as smoking status, physical activity and body mass index (BMI).

The Imperial team carried out the study, which is published in eClinicalMedicine, in collaboration with researchers from the International Agency for Research on Cancer (IARC), University of São Paulo, and NOVA University Lisbon.

Previous research from the team reported the levels of consumption of ultra-processed foods in the UK, which are the highest in Europe for both adults and children. The team also found that higher consumption of ultra-processed foods was associated with a greater risk of developing obesity and type 2 diabetes in UK adults, and a greater weight gain in UK children extending from childhood to young adulthood.

Dr Eszter Vamos, lead senior author for the study, from Imperial College London’s School of Public Health, said: “This study adds to the growing evidence that ultra-processed foods are likely to negatively impact our health including our risk for cancer. Given the high levels of consumption in UK adults and children, this has important implications for future health outcomes.

“Although our study cannot prove causation, other available evidence shows that reducing ultra-processed foods in our diet could provide important health benefits. Further research is needed to confirm these findings and understand the best public health strategies to reduce the widespread presence and harms of ultra-processed foods in our diet.”

Dr Kiara Chang, first author for the study, from Imperial College London’s School of Public Health, said: “The average person in the UK consumes more than half of their daily energy intake from ultra-processed foods. This is exceptionally high and concerning as ultra-processed foods are produced with industrially derived ingredients and often use food additives to adjust colour, flavour, consistency, texture, or extend shelf life.

“Our bodies may not react the same way to these ultra-processed ingredients and additives as they do to fresh and nutritious minimally processed foods. However, ultra-processed foods are everywhere and highly marketed with cheap price and attractive packaging to promote consumption. This shows our food environment needs urgent reform to protect the population from ultra-processed foods.”

The World Health Organisation and the United Nations’ Food and Agriculture Organisation has previously recommended restricting ultra-processed foods as part of a healthy sustainable diet.

There are ongoing efforts to reduce ultra-processed food consumption around the world, with countries such as Brazil, France and Canada updating their national dietary guidelines with recommendations to limit such foods. Brazil has also banned the marketing of ultra-processed foods in schools. There are currently no similar measures to tackle ultra-processed foods in the UK.

Dr Chang added: “We need clear front of pack warning labels for ultra-processed foods to aid consumer choices, and our sugar tax should be extended to cover ultra-processed fizzy drinks, fruit-based and milk-based drinks, as well as other ultra-processed products.

“Lower income households are particularly vulnerable to these cheap and unhealthy ultra-processed foods. Minimally processed and freshly prepared meals should be subsidised to ensure everyone has access to healthy, nutritious and affordable options.”

The researchers note that their study is observational, so does not show a causal link between ultra-processed foods and cancer due to the observational nature of the research. More work is needed in this area to establish a causal link.

Coffee with milk may have an anti-inflammatory effect

 

Can something as simple as a cup of coffee with milk have an anti-inflammatory effect in humans? Apparently so, according to a new study from the University of Copenhagen. A combination of proteins and antioxidants doubles the anti-inflammatory properties in immune cells. The researchers hope to be able to study the health effects on humans.

Whenever bacteria, viruses and other foreign substances enter the body, our immune systems react by deploying white blood cells and chemical substances to protect us. This reaction, commonly known as inflammation, also occurs whenever we overload tendons and muscles and is characteristic of diseases like rheumatoid arthritis.

Antioxidants known as polyphenols are found in humans, plants, fruits and vegetables. This group of antioxidants is also used by the food industry to slow the oxidation and deterioration of food quality and thereby avoid off flavors and rancidity. Polyphenols are also known to be healthy for humans, as they help reduce oxidative stress in the body that gives rise to inflammation.

But much remains unknown about polyphenols. Relatively few studies have investigated what happens when polyphenols react with other molecules, such as proteins mixed into foods that we then consume.

In a new study, researchers at the Department of Food Science, in collaboration with researchers from the Department of Veterinary and Animal Sciences, at University of Copenhagen investigated how polyphenols behave when combined with amino acids, the building blocks of proteins. The results have been promising.

"In the study, we show that as a polyphenol reacts with an amino acid, its inhibitory effect on inflammation in immune cells is enhanced. As such, it is clearly imaginable that this cocktail could also have a beneficial effect on inflammation in humans. We will now investigate further, initially in animals. After that, we hope to receive research funding which will allow us to study the effect in humans," says Professor Marianne Nissen Lund from the Department of Food Science, who headed the study.

The study has just been published in the Journal of Agricultural and Food Chemistry.

Twice as good at fighting inflammation

To investigate the anti-inflammatory effect of combining polyphenols with proteins, the researchers applied artificial inflammation to immune cells. Some of the cells received various doses of polyphenols that had reacted with an amino acid, while others only received polyphenols in the same doses. A control group received nothing.

The researchers observed that immune cells treated with the combination of polyphenols and amino acids were twice as effective at fighting inflammation as the cells to which only polyphenols were added.

"It is interesting to have now observed the anti-inflammatory effect in cell experiments. And obviously, this has only made us more interested in understanding these health effects in greater detail. So, the next step will be to study the effects in animals," says Associate Professor Andrew Williams of the Department of Veterinary and Animal Sciences at the Faculty of Health and Medical Sciences, who is also senior author of the study.

Found in coffee with milk
Previous studies by the researchers demonstrated that polyphenols bind to proteins in meat products, milk and beer. In another new study [link: https://doi.org/10.1016/j.foodchem.2022.134406], they tested whether the molecules also bind to each other in a coffee drink with milk. Indeed, coffee beans are filled with polyphenols, while milk is rich in proteins.

"Our result demonstrates that the reaction between polyphenols and proteins also happens in some of the coffee drinks with milk that we studied. In fact, the reaction happens so quickly that it has been difficult to avoid in any of the foods that we’ve studied so far," says Marianne Nissen Lund.

Therefore, the researcher does not find it difficult to imagine that the reaction and potentially beneficial anti-inflammatory effect also occur when other foods consisting of proteins and fruits or vegetables are combined.

"I can imagine that something similar happens in, for example, a meat dish with vegetables or a smoothie, if you make sure to add some protein like milk or yogurt," says Marianne Nissen Lund.   

Industry and the research community have both taken note of the major advantages of polyphenols. As such, they are working on how to add the right quantities of polyphenols in foods to achieve the best quality. The new research results are promising in this context as well:

"Because humans do not absorb that much polyphenol, many researchers are studying how to encapsulate polyphenols in protein structures which improve their absorption in the body. This strategy has the added advantage of enhancing the anti-inflammatory effects of polyphenols," explains Marianne Nissen Lund.

The research is funded by Independent Research Fund Denmark and conducted in collaboration with the Technical University of Dresden in Germany.

Polyphenol Facts

• Polyphenols are a group of naturally occurring antioxidants important for humans.
• They prevent and delay the oxidation of healthy chemical substances and organs in our bodies, thereby protecting them from damage or destruction.
• Polyphenols are found in a variety of fruits and vegetables, tea, coffee, red wine and beer.
• Due to their antioxidant properties, polyphenols are used in the food industry to minimize the oxidation of fats in particular, as well as the quality deterioration of foods, to avoid off flavours and rancidity.

Sports-related sudden cardiac arrest is rare in older adults

 

FINDINGS

The annual incidence of sports-related sudden cardiac arrest in older adults is rare: 2 to 3 cases per 100,000 people.

Of the 4,078 total sudden cardiac arrest cases studied in people 65 and older, 77 (1.9%) occurred during or following an exercise activity, such as cycling, gym workout, running, or playing golf or tennis. Most of the cardiac arrests occurred in men (91%). 

Investigators also analyzed medical records, which were available for 47 people with sports-related cardiac arrest and 3,162 for people with non-sports-related cardiac arrest. This analysis revealed that people who experienced sudden cardiac arrest during or shortly after exercise were more likely to have fewer cardiovascular risk factors and other health issues than people who did not experience exercise-related sudden cardiac arrest. 

People who experienced sports-related cardiac arrest were also more likely to experience it in a public location, which contributed to being four times more likely to survive than those who experienced a non-sports-related cardiac arrest. 

BACKGROUND

A sudden cardiac arrest occurs when an electrical malfunction causes a person’s heart to stop beating. This is an extremely dangerous event, with most people dying within minutes. The good news is that in recent years, the occurrence of sudden cardiac arrest has decreased among people of working age. But for older people, the rates of sudden cardiac arrest have increased. 

Exercise is one of the most heart-healthy habits to engage in. In rare cases, however, it can trigger an irregular heart rhythm that leads to sudden cardiac arrest. 

METHODS

Investigators analyzed sudden cardiac arrests that have occurred among people age 65 and older in Portland, Oregon, and Ventura County, California. To do this, they reviewed data collected as part of two prospective studies: The Oregon Sudden Unexpected Death Study, which has been ongoing since 2002, and the Ventura Prediction of Sudden Death in Multi-ethnic Communities study, which has been ongoing since 2015. The data excluded people who experienced sudden cardiac arrest while hospitalized and people for whom resuscitation was not attempted. 

People who died from sudden cardiac arrest during sports activity or within one hour of the activity were categorized as having sports-related sudden cardiac arrest. 

IMPACT

The findings reveal that even though sports activity is steadily rising in older adults, sudden cardiac arrest triggered by sports activity is uncommon. Furthermore, people who have sudden cardiac arrest with exercise tend to have fewer comorbidities and cardiovascular risk factors than people who have sudden cardiac arrest not triggered by exercise. Taken together, the benefits of sports activity likely outweigh the risk of associated sudden cardiac arrest risk, the authors conclude. 

“The annual incidence of sports-related sudden cardiac arrest among older adults is extremely rare,” said Sumeet S. Chugh, MD, the Pauline and Harold Price Chair in Cardiac Electrophysiology Research, director of the Heart Rhythm Center in the Smidt Heart Institute at Cedars-Sinai, and senior author of the study. “This means older people who regularly participate in sports should continue. Those who develop new symptoms should consult their physician. Those who want to start should be encouraged to do so, but only after consulting their physician and obtaining an exercise prescription.”

The research was published in the peer-reviewed journal JACC: Clinical Electrophysiology.

Mixed tree nuts: positive impact on cardiovascular risk factors and increase serotonin

 

In a paper[1] published online this week in the journal, Nutrients, researchers found that consuming mixed tree nuts (almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts) had a positive effect on the metabolism of the essential amino acid, tryptophan, in overweight and obese individuals. Specifically, there was an increase in both cardioprotective tryptophan metabolites and in the neurotransmitter, serotonin.

 

In a previous study[2], researchers at UCLA demonstrated that consuming 1.5 ounces of tree nuts per day (versus pretzels) during 24 weeks of weight loss and weight maintenance, resulted in weight loss, increased satiety, decreased diastolic blood pressure and decreased heart rate. Tryptophan (found in tree nuts) has been indicated as an important factor in cardiovascular disease (CVD). It is metabolized in the gut, producing many bioactive metabolites that are important in immune regulation affecting chronic diseases such as diabetes and CVD. The current study looked at whether tree nut snacks, as part of a hypocaloric diet, could modify the gut microbiome, resulting in increased levels of cardio-protective tryptophan microbial metabolites.

 

Plasma and stool samples were collected from 95 overweight or obese participants and were evaluated in the current study for tryptophan metabolites and for gut microbiota. “We’ve known for a long time that tree nuts can help decrease CVD risk, and these findings provide some possible explanations,”

. “We discovered some new associations between tryptophan metabolites and blood pressure, heart rate, and satiety in overweight/obese subjects, suggesting a broader impact of tryptophan metabolism in overall health, including cardiovascular health.”

 

Another interesting finding was the significant increase in blood serotonin levels (60.9% and 82.2% increase from baseline at week 12 and 24, respectively) in both the weight loss and weight maintenance phases, in the those who consumed mixed tree nuts. “This is the first time we’ve seen mixed tree nut consumption associated with an increase in serotonin levels in the body,” explained Dr. Li. “While more research is needed, this is exciting since serotonin can have an important impact on mood and overall mental health.”

 

Research has shown that people get about 25% of their calories each day from snacks and a large proportion come from desserts, sugar-sweetened beverages, sweets and salty snacks.[3] “Replacing just one of those snacks with 1.5 ounces of tree nuts may help improve overall health and reduce the risk for various chronic diseases,” stated Maureen Ternus, M.S., R.D.N, Executive Director of the International Tree Nut Council Nutrition Research & Education Foundation.

Healthy lifestyle linked to slower memory decline in older adults

A healthy lifestyle, in particular a healthy diet, is associated with slower memory decline, finds a decade-long study of older adults in China, published today in The BMJ.

Even for carriers of the apolipoprotein E (APOE) gene - the strongest known risk factor for Alzheimer’s disease and related dementias - a healthy lifestyle was found to slow memory loss.

Memory continuously declines as people age, but evidence from existing studies is insufficient to assess the effect of a healthy lifestyle on memory in later life. And given the many possible causes of memory decline, a combination of healthy behaviours might be needed for an optimal effect.

To explore this further, researchers analysed data from 29,000 adults aged at least 60 years (average age 72; 49% women) with normal cognitive function who were part of the China Cognition and Aging Study.

At the start of the study in 2009, memory function was measured using the Auditory Verbal Learning test (AVLT) and participants were tested for the APOE gene (20% were found to be carriers). Follow-up assessments were then conducted over the next 10 years in 2012, 2014, 2016, and 2019.

A healthy lifestyle score combining six factors was then calculated: healthy diet, regular exercise, active social contact (eg. seeing friends and family), cognitive activity (eg. writing, reading, playing mahjong), non-smoking, and never drinking alcohol. 

Based on their score, ranging from 0 to 6, participants were put into favourable (4 to 6 healthy factors), average (2 to 3 healthy factors), or unfavourable (0 to 1 healthy factors) lifestyle groups and into APOE carrier and non-carrier groups.

After accounting for a range of other health, economic and social factors, the researchers found that each individual healthy behaviour was associated with a slower than average decline in memory over 10 years.

A healthy diet had the strongest effect on slowing memory decline, followed by cognitive activity and then physical exercise.

Compared with the group that had unfavourable lifestyles, memory decline in the favourable lifestyle group was 0.28 points slower over 10 years based on a standardised score (z score) of the AVLT, and memory decline in the average lifestyle group was 0.16 points slower.

Participants with the APOE gene with favourable and average lifestyles also experienced a slower rate of memory decline than those with an unfavourable lifestyle (0.027 and 0.014 points per year slower, respectively).

What’s more, those with favourable or average lifestyles were almost 90% and almost 30% less likely to develop dementia or mild cognitive impairment relative to those with an unfavourable lifestyle, and the APOE group had similar results. 

This is an observational study so can’t establish cause and the researchers acknowledge some limitations, such as the potential for measurement errors due to self-reporting of lifestyle factors, and the possibility of selection bias, as some participants did not return for follow-up evaluations.

But this was a large study with a long follow-up period, allowing for evaluation of individual lifestyle factors on memory function over time. And findings remained significant after further analyses, suggesting that they are robust.

As such, the researchers say their results provide strong evidence that adherence to a healthy lifestyle with a combination of positive behaviours is associated with a slower rate of memory decline, even for people who are genetically susceptible to memory decline. 

They suggest further research could focus on the effects of a healthy lifestyle on memory decline across the lifespan, acknowledging that memory problems can also affect younger people, not included in this study. “These results might offer important information for public health initiatives to protect older adults against memory decline,” they conclude.

“Prevention is important, given the absence of effective treatments for Alzheimer’s disease and related dementias,” say researchers in a linked editorial.

However, they point out that these results do not help to determine which among the six health behaviours included in the score (or specific combination) is the best target for dementia prevention, or when in the life course to focus prevention efforts. Further insight is also needed to determine whether the differences in memory decline observed in this study are clinically meaningful, they add.

They suggest a similar approach that led to a substantial reduction in cardiovascular disease should be taken with dementia prevention, “identifying not only the factors that matter most but also the threshold at which they matter, and the age when intervention is likely to be most effective.”

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JOURNAL

The BMJ

DOI

10.1136/bmj-2022-072691 

Lifelong marriage lowers risk of dementia

If you are married continuously for many years in mid-life, you have a lower risk of developing dementia in old age. This has been confirmed by a recently published study based on data from HUNT Study health surveys in Nord-Trøndelag.

“Being married can have an influence on risk factors for dementia,” says Vegard Skirbekk at the Norwegian Institute of Public Health (NIPH/FHI).

The researchers looked at different types of marital status in people over a period of 24 years – from the age of 44 until 68 – and investigated whether this status was related to a clinical diagnosis of dementia or mild cognitive impairment (MCI) after the age of 70.

The results show that the group that was continuously married throughout the period had the lowest incidence of dementia.

The highest incidence was found in divorced and single people.

Children reduce risk

Asta Håberg is a doctor at St. Olav's Hospital and a professor at the Norwegian University of Science and Technology (NTNU), as well as a researcher at NIPH/FHI. She says the results of the survey contained surprises.

“Exactly what causes dementia is a mystery. This survey indicates that being married and a lower risk of dementia are linked, but we don't know why,” says Håberg.

“One theory has been that people who are married live healthier lives, and that this explains differences in the risk of various diseases. In this survey, we found no support for health differences between married and unmarried people that would explain the difference in dementia risk.”

In the HUNT survey, approximately 150 000 people living in the former country of Nord-Trøndelag have given consent for their health information to be made available for research. The researchers used this data to check the incidence of dementia against health factors such as smoking, high blood pressure, obesity, physical inactivity, diabetes, psychological problems and having close friends.

“We thought that these factors would mean something, but they didn’t explain anything,” says Håberg.

However, the researchers found that having children had significance and reduced the risk of dementia by 60 per cent among the unmarried people in the study.

“Some people have theorized that if you have children, you stay more cognitively engaged. For example, you have to deal with people and participate in activities that you wouldn’t otherwise have to. This stimulates your brain so that it possibly works better. That way you build up a kind of cognitive reserve,” says Håberg.

Still a lot of unused data

This "reserve" in the brain is not structural. It doesn’t show up on an MRI scan or by opening the brain and looking inside. It is part of the "mystery of dementia". But Håberg hopes to be able to uncover some of the mystery through this study.

“We don’t know whether it’s being married or having children that protects against dementia, or if it’s a case of pre-selection, for example. This would mean that people who have a lower probability of developing dementia also have a higher probability of finding a partner and having children. But the fact that we have the HUNT Study means that we have a lot of data available that we haven’t yet used to investigate this further,” Håberg says.

As a doctor, she is not convinced that dementia is an inevitable consequence of aging.

“It’s common to think that 'if you live long enough, sooner or later you’ll develop dementia'. I'm not so sure I agree with that, given this theory that we may have cognitive reserves,” she said. "It could be that certain conditions might help to build up such reserves, which means that you start with more connections in the brain. For example, we’ve observed that education is a factor, and that the more education you have, the better the "reserves" that you build up."

And yet, when a highly educated person gets Alzheimer's, the disease progresses just as quickly as for anyone else. The reserves thus have a delaying effect – but only until the disease strikes.

Make it easier to have children

The study results are part of the research project REFAWOR (Cognitive reserve work and family) funded by the NIH in the USA, which is part of the programme "Changing lives, changing brains" under the auspices of the Norwegian Institute of Public Health.

REFAWOR has a budget of almost three million euros and aims to study how changes in living and working conditions affect the risk of Alzheimer's, dementia and cognitive impairment in older people. These diseases are expected to triple by 2050.

The researchers are now taking a closer look at the significance of having children for dementia risk, the types of work people have and how retirement age can affect the risk.

Dementia is a collective term for various diseases and injuries in the brain. Memory weakens, and the ability to think logically is affected. Eventually it becomes difficult to manage on your own and carry out everyday activities. No medical treatment for dementia is currently available.

“We’ve dreamt of finding a medicine for dementia for a long time, but we haven’t yet succeeded. So we’re looking at social determinants. What can society do to reduce the risk? The state could facilitate having children, for example,” says Håberg.

Genes can make us more susceptible

One of the next steps is to look at genetic connections, says Skirbekk.

“We know that certain genes increase the risk of dementia, but people with these genes can still live to be 90 years old without experiencing cognitive problems,” he says.

“You could say that the increased risk inherent in the genes can be regarded as a vulnerability, where having a stable family life might possibly reduce this vulnerability.

He emphasizes that this study says nothing about the biological mechanisms behind dementia.

“But it shows that being married can have an influence on risk factors. You become more cognitively active, you cope better with adversity and are less subject to stress. The partner represents a security that provides a buffer.”

The study does not consider whether any difference exists between being an unmarried versus a married couple. Less than one per cent of unmarried people in the survey were cohabiting with a partner.

“There are very few cohabitants in this age group in HUNT,” says Håberg.

Reference:

Vegard Skirbekk, Catharine E. Bowen, Asta Håberg, Steinar Krogstad et al: Marital Histories and Associations With Later-Life Dementia and Mild Cognitive Impairment Risk in the HUNT4 70+ Study in Norway, Journal of Aging and Health.

https://doi.org/10.1177/08982643221131

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JOURNAL

Journal of Aging and Health

DOI

10.1177/08982643221131926 

More steps, moderate physical activity cuts dementia, cognitive impairment risk

Peer-Reviewed Publication

 

IMAGE: ANDREA LACROIX, PH.D., M.P.H., DISTINGUISHED PROFESSOR AT THE UC SAN DIEGO HERBERT WERTHEIM SCHOOL OF PUBLIC HEALTH AND HUMAN LONGEVITY SCIENCE view more 

CREDIT: UNIVERSITY OF CALIFORNIA SAN DIEGO

Senior women were less likely to develop mild cognitive impairment or dementia if they did more daily walking and moderate-to-vigorous physical activity, according to a new study led by the Herbert Wertheim School of Public Health and Human Longevity Science at University of California San Diego.

In the Jan. 25, 2023 online edition of Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, the team reported that, among women aged 65 or older, each additional 31 minutes per day of moderate-to-vigorous physical activity was associated with a 21 percent lower risk of developing mild cognitive impairment or dementia. Risk was also 33 percent lower with each additional 1,865 daily steps.

“Given that the onset of dementia begins 20 years or more before symptoms show, the early intervention for delaying or preventing cognitive decline and dementia among older adults is essential,” said senior author Andrea LaCroix, Ph.D., M.P.H., Distinguished Professor at the Herbert Wertheim School of Public Health and Human Longevity Science at UC San Diego.

While there are several types, dementias are a debilitating neurological condition that can cause loss of memory, the ability to think, problem solve or reason. Mild cognitive impairment is an early stage of memory loss or thinking problems that is not as severe as dementias.

According to the United States Department of Health and Human Services, dementia affects more than 5 million people in this country. That number is expected to double by 2050. 

More women live with and are at higher risk of developing dementia than men.

“Physical activity has been identified as one of the three most promising ways to reduce risk of dementia and Alzheimer’s disease. Prevention is important because once dementia is diagnosed, it is very difficult to slow or reverse. There is no cure,” said LaCroix.

However, because few large studies have examined device measures of movement and sitting in relation to mild cognitive impairment and dementia, much of the published research on the associations of physical activity and sedentary behavior with cognitive decline and dementia is based on self-reported measures, said first author, Steven Nguyen, Ph.D., M.P.H., postdoctoral scholar at the Herbert Wertheim School of Public Health.

For this study, the researchers sampled data from 1,277 women as part of two Women’s Health Initiative (WHI) ancillary studies — the WHI Memory Study (WHIMS) and the Objective Physical Activity and Cardiovascular Health (OPACH) study. The women wore research-grade accelerometers and went about their daily activities for up to seven days to obtain accurate measures of physical activity and sitting.

The activity trackers showed the women averaged 3,216 steps, 276 minutes in light physical activities, 45.5 minutes of moderate-to-vigorous physical activity and 10.5 hours of sitting per day. Examples of light physical activity could include housework, gardening or walking. Moderate-to-vigorous physical activity could include brisk walking.

The study findings also showed that higher amounts of sitting and prolonged sitting were not associated with higher risk of mild cognitive impairment or dementia.

Together, this information has clinical and public health importance as there is little published information on the amount and intensity of physical activity needed for a lower dementia risk, said Nguyen.

“Older adults can be encouraged to increase movement of at least moderate intensity and take more steps each day for a lower risk of mild cognitive impairment and dementia,” said Nguyen.

“The findings for steps per day are particularly noteworthy because steps are recorded by a variety of wearable devices increasingly worn by individuals and could be readily adopted.”

The authors said further research is needed among large diverse populations that include men.

Co-authors include: John Bellettiere, UC San Diego; Kathleen M. Hayden and Stephen R. Rapp, Wake Forest University School of Medicine; Chongzhi Di, Fred Hutchinson Cancer Center; Priya Palta, Columbia University Irving Medical Center; Marcia L. Stefanick, Stanford University School of Medicine; JoAnn E. Manson, Harvard Medical School; and Michael J. LaMonte, University at Buffalo – SUNY.

This research was funded, in part, by the National Institute on Aging (P01 AG052352, 5T32AG058529-03) and the National Heart, Lung, and Blood Institute (R01 HL105065). The Women’s Health Initiative was funded by the National Heart, Lung, and Blood Institute (75N92021D00001, 75N92021D00002, 75N92021D00003, 75N92021D00004, 75N92021D00005).