Healthy diet during pregnancy associated with reduced risk of infant colic, eczema

Key points:

• Infants born to mothers who ate a healthy, Mediterranean-style diet during pregnancy were at significantly lower risk for colic and eczema, while those born to mothers who ate a less healthy, more inflammatory diet were at higher risk.

• For each weekly serving of seafood a pregnant woman consumed, her infant had a 25% lower chance of having colic and eczema.

• The study is the first to examine how prenatal diet influences infant colic and eczema, which prior studies by the researchers linked to higher risk of developing allergic conditions, such as asthma and food allergies, later in life.

Boston, MA—Infants born to mothers who ate a healthy, Mediterranean-style diet during pregnancy were at lower risk for colic and eczema, according to a new study by researchers at Harvard T.H. Chan School of Public Health, Boston Children’s Hospital, and Harvard Pilgrim Health Care Institute. The researchers also found that regularly consuming seafood during pregnancy helped lower an infant’s risk for these conditions.

“Our own prior studies have shown that babies who had colic have higher rates of atopic conditions in later life, including asthma, seasonal rhinitis and food allergies,” said corresponding author Jenifer Lightdale, associate chief of the Division of Gastroenterology, Hepatology and Nutrition at Boston Children’s Hospital and professor of pediatrics at Harvard Medical School. “Our new study is the first to ask how prenatal diet may influence colic, and in particular the combination of colic and eczema, as babies who have both conditions in infancy may be at highest risk for various manifestations of allergies when they are older.”

The study will be published Oct. 12 in JAMA Network Open.

Previous research on diet and colic has focused on whether dietary changes after birth in breastfeeding mothers, or in choices of infant formulas, can affect the symptoms of colic once they are present. For this study, the researchers examined whether the dietary habits of women during pregnancy would be associated with the risk of colic in her baby, particularly the combination of colic and eczema.

More than 1,300 pregnant women were recruited into the Project Viva study from prenatal clinics in Eastern Massachusetts from April 1999 to November 2002. The participants filled out regular food questionnaires, which the researchers scored according to the Mediterranean Diet Score (MDS) and the Dietary Inflammation Index (DII). A high MDS score indicated a more healthful diet, with high intake of fruits, vegetables, whole grains, legumes, and healthy fats, and moderate intake of dairy and lean proteins. A high DII score indicated a less healthful diet, with high intake of red or processed meats, sugar-sweetened beverages, sodium, and refined grains. Participants also reported their intake of commonly allergenic foods, including peanuts, peanut butter, and other nuts; finfish and shellfish; and eggs and dairy.

The researchers found that 26% of the study’s infants had colic, and 5% had both colic and eczema. Mothers who adhered more closely to a Mediterranean diet had a significantly lower risk of having a baby with both colic and eczema: Each higher MDS point was associated with a 15% reduction in risk. By contrast, each higher DII point was associated with a 34% higher risk.

Looking at foods known to be common allergens, the researchers found that for each weekly serving of seafood a pregnant woman consumed, her infant had a 25% lower chance of having colic and eczema. Other typical allergenic foods—including dairy, eggs, and nuts—were not related to having a baby with colic and eczema. The researchers calculated that all of the associations the study found were strongest among infants whose mothers had a history of allergic conditions.

“Our findings provide yet another reason to help pregnant women achieve a healthy, balanced diet, with a particular emphasis on eating seafood,” said first author Emily Oken, president of the Harvard Pilgrim Health Care Institute and professor in the Department of Nutrition at Harvard Chan School. “Moms wish to do all they can for their babies, but there are often financial and other structural barriers to accessing healthy nutrition. We hope our study can be helpful not just to individuals and families, but also to programs and services that support women’s health and nutrition, including federal programs like WIC and SNAP as well as programs administered by health plans and systems, such as ‘food is medicine’ initiatives.”

Article information

“Maternal Prenatal Diet and Colic and Eczema Among Infants,” Emily Oken, Sheryl L. Rifas-Shiman, Karen M. Switkowski, Kari Nadeau, Jenifer R. Lightdale, JAMA Network Open, October 12, 2026, doi: 10.1001/jamanetworkopen.2026.38472

Cannabis does not help you sleep better

 

• Study followed adults for 35 years, from young adulthood into middle age
• Long-term cannabis use linked to lower sleep quality measured by wrist-worn monitors
• Findings suggest cannabis-related sleep disruptions may go unnoticed by users themselves
• Sleep medicine expert offers well-established strategies that can improve sleep quality

Millions of Americans use cannabis products as sleep aids, but a new Northwestern Medicine study suggests marijuana may not improve sleep the way many people believe it does. 

The study found both lifetime and recent cannabis use were associated with poorer objectively measured sleep quality, even though participants generally did not perceive their sleep to be worse. 

The scientists followed participants from young adulthood into middle age for nearly 35 years, repeatedly tracking their cannabis use over time. In middle age, participants wore a wrist-based sleep monitor for a week and completed sleep surveys, allowing the scientists to compare objective measures of sleep with participants' own perceptions of how well they slept.

The study found both long-term and recent cannabis use were associated with poorer sleep quality when the wrist-worn monitoring device objectively measured participants’ sleep. However, participants who used cannabis generally did not report sleeping worse than people who didn't use it. The findings suggest cannabis-related sleep disruptions may go unnoticed by users themselves, the study authors said. 

The study was published today (Oct. 9) in JAMA Network Open. 

“This study challenges the common belief that cannabis helps people sleep better,” said corresponding author Dr. Thanh-Huyen T. Vu, research associate professor of preventive medicine (epidemiology) at Northwestern University Feinberg School of Medicine. “Our findings suggest cannabis may actually be associated with poorer sleep quality, even if people don't perceive those changes.” 

While the study was not designed to determine whether cannabis directly causes sleep problems, it provides some of the strongest evidence to date that long-term recreational cannabis use and better sleep quality may not be as closely aligned as commonly believed.

“Our data do not support the belief that cannabis is helpful as a sleep aid,” said senior author Mercedes R. Carnethon, chair of the department of preventive medicine at Feinberg. “As cannabis becomes increasingly available and accepted, it's important to better understand its long-term associations with health behaviors such as sleep.”

A breakdown of the study findings

The study analyzed data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study, a long-running, community-based study that began in 1985-86 and follows Black and white adults across the U.S. 

Among 1,266 participants, the study found greater lifetime cannabis exposure was associated with poorer objective sleep quality. People with higher cumulative cannabis use spent a lower percentage of the night asleep, experienced more fragmented sleep and spent more time awake after initially falling asleep.

Recent cannabis users showed similar patterns. Compared with people who never used cannabis, recent users were more likely to have lower sleep efficiency, greater sleep fragmentation and longer periods of wakefulness during the night. They also were significantly more likely to sleep longer than eight hours per night, the study found. 

When researchers asked study participants to rate their own sleep quality, however, cannabis use showed no association with whether people felt they slept well or poorly.

“This was one of the most interesting findings,” Vu said. “The wearable device detected more nighttime disruption among participants with long-term cannabis exposure, but the participants themselves generally did not report worse sleep.”

After adjusting for numerous factors known to affect sleep — age, sex, race, cigarette smoking, alcohol use, physical activity, depression, chronic health conditions and use of other substances — cannabis use remained associated with poorer objectively measured sleep, the study found. 

The researchers did not distinguish between modes of cannabis consumption (e.g., smoking versus consuming edibles). Given that the participants were followed over several decades, patterns of cannabis use likely changed over time, which the study authors said makes this an especially important question for future studies.

Better ways to support healthy sleep

While cannabis may not be the sleep solution many people believe it is, there are well-established strategies that can improve sleep quality, said study co-author Kristen L. Knutson, associate professor of neurology (sleep medicine) and preventive medicine (epidemiology) at Feinberg.

“Keep a regular bedtime, make your bedroom cool, dark and quiet, and avoid looking at phones and other screens right before bed,” Knutson said. “It can also help to establish a calming routine before sleep, such as reading, meditating or taking a shower. If sleep problems persist, or if you're a loud snorer, talk with your health care provider to rule out an underlying sleep disorder.”

The study is titled, “Recent and Cumulative Cannabis Use and Sleep in Middle-Aged Adults.”

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Journal

JAMA Network Open

DOI

10.1001/jamanetworkopen.2026.38303

Bending forwards at work may be an overlooked risk for pregnant women

 

Pregnant women who frequently bend forward at work could face an increased risk of miscarriage, according to a new study from the University of Copenhagen. The researchers believe that greater attention should be paid to the working environment in early p

Peer-Reviewed Publication

University of Copenhagen

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Up to 20% of pregnancies end in miscarriage. That’s why it is important to understand whether some risk factors can be prevented. A new study from the University of Copenhagen and Bispebjerg Hospital suggests that an overlooked factor may increase the risk of pregnancy loss: working in a bent-forward position.

The researchers analysed data from 800,000 pregnancies and found that for every hour women spent working bent forward, the risk of miscarriage increased by 36%. In addition, each hour of walking or standing work was associated with an increased risk of pregnancy loss of 18% and 3%, respectively.

"Losing a pregnancy is devastating for a woman, so if there is anything we can do to help prevent it, it is important that workplaces are aware of how the risk may be reduced," says Luise Mølenberg Begtrup, Clinical Associate Professor at the Department of Public Health, University of Copenhagen.

Gardeners and waiters often work bent forward

In the study, the researchers analysed more than 800,000 pregnancies among 475,000 women between 2004 and 2018 and linked these data with measurements of occupational postures.

More than 400 women wore sensors on their backs and thighs while working. The sensors recorded how much they walked, stood and bent forward during a typical working week across 100 different occupations.

Occupations involving frequent forward bending included waiters, agricultural workers, gardeners and tradespeople. Prolonged standing was particularly common among jobs such as bakers, shop assistants and painters, while occupations involving a high degree of walking included waiters, chefs, food production workers and refuse collectors.

"When people are asked how many hours they spent walking during a working day, for example, they often find it difficult to remember accurately and tend to overestimate. With this method, we avoid relying on self-assessments, which reduces uncertainty," says Hannah Nørtoft Frankel, physician at Bispebjerg Hospital and lead author of the study, which was part of her PhD project at the University of Copenhagen.

The study found that forward-bending work in particular increased the relative risk of miscarriage. The risk increased by 36% for each additional hour spent working bent forward.

"That is quite a high figure. On the other hand, it is relatively rare for people to spend more than an hour in total bent forward during a working day. In fact, the average worker spent only 24 minutes a day in a bent-forward position," says Luise Mølenberg Begtrup.

Unclear why

In the study, the overall risk of miscarriage among participants was 10%, somewhat lower than the risk in the general population. However, for women who spent one hour working bent forward, the risk of miscarriage was 13.6%, corresponding to a 36% increase compared with the overall risk.

The researchers do not yet know why working bent forward appears to be particularly risky during pregnancy.

"The underlying mechanism remains poorly understood. One possible explanation is that bending forward may restrict blood flow to the placenta. It could also be that it triggers stress hormones that induce contractions in the uterus, which could potentially lead to miscarriage," says Hannah Nørtoft Frankel.

The researchers emphasise that the study does not show that physical work directly causes miscarriage. Most miscarriages result from factors beyond the control of either the pregnant woman or her workplace, and the findings point only to a statistical association that requires further investigation.

Employers should be aware

The researchers stress that pregnant women should not be worried about going to work, even if their job involves walking, standing or bending forward.

"In general, it is healthy to remain active and continue working during an uncomplicated pregnancy. However, there are occupations where employers should pay attention to whether a pregnant employee spends much of the working day standing, walking or bending forward. In such cases, employers should consider how tasks can be adjusted and work adapted accordingly," says Luise Mølenberg Begtrup.

Often, relatively small adjustments can make a difference, such as taking more seated breaks during the day or providing a chair instead of requiring employees to stand. It may also be possible to swap tasks with a colleague for a period.

Employers are required to discuss working conditions with pregnant employees to assess and adapt the working environment where necessary. However, current recommendations from the Danish Working Environment Authority concerning standing and walking work apply only from the fourth month of pregnancy onwards in Denmark. The researchers believe this is too late, since most miscarriages occur earlier in pregnancy.

"We believe these recommendations should apply throughout pregnancy," says Hannah Nørtoft Frankel.

The researchers hope that the findings will help both pregnant women and employers assess working postures throughout pregnancy.

"If someone feels they are exposed to particularly demanding working conditions and is unsure whether these could pose a risk to their pregnancy, they can always be referred for an individual risk assessment and guidance at an occupational medicine department," says Luise Mølenberg Begtrup.

 

About the study

• 803,829 pregnancies among 475,312 women were analysed.
• The study used data from 2004 to 2018.
• 10.1% of pregnancies ended in miscarriage.
• The researchers examined occupational standing, walking and forward bending, defined as bending more than 30 degrees.
• 400 women wore accelerometers while working to record their movements.
• For occupations with insufficient measurement data, the researchers supplemented their analyses with expert assessments of working postures.
• Each hour of forward-bending work was associated with a 36% increase in the relative risk of miscarriage, while each hour of walking and standing work increased the risk by 18% and 3%, respectively.
• The researchers cannot determine whether the increase in pregnancy loss is directly caused by work. Other factors, such as smoking and the pregnant woman's overall health, may also play a role.

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Journal

Occupational and Environmental Medicine

DOI

10.1136/oemed-2025-110712 

Pistachios can support sleep

 Nearly one-third of U.S. adults report sleeping less than seven hours a night, below the minimum amount recommended for most adults, while nearly one in five has trouble staying asleep most days or every day. At the same time, nearly one-third of Americans say they are seeking improved sleep from foods, beverages or nutrients. 

Pistachios have attracted researchers’ attention because they naturally bring together several nutrients and plant compounds connected to sleep. Now, a new narrative review* published in Nutrition Research Reviews identifies pistachios as a promising whole food for sleep research and explores how their nutrient profile may influence processes related to sleep quality, falling asleep, staying asleep and regulation of the sleep–wake cycle. 

The review published in Nutrition Research Reviews states that the recommended intake of tryptophan is 5 mg/kg body weight, or about 350 mg/day for a 70-kg (154-lb) adult. A 1-ounce serving of pistachios provides about 71 mg.

Three reasons pistachios are intriguing to sleep researchers and clinicians: 

• Supporting the body’s production of melatonin: Pistachios provide tryptophan, vitamin B6 and magnesium, which the body uses in the production of serotonin and melatonin. Serotonin is involved in sleep regulation and is also used to make melatonin, the hormone that helps regulate the sleep–wake cycle. Pistachios also contain phytomelatonin, the form of melatonin produced by plants, although its absorption and effects from eating pistachios have not been established in people.  

• Supporting calming signals in the brain: Pistachios provide vitamin B6 and magnesium, which are involved in the production and function of gamma-aminobutyric acid (GABA), a brain chemical that helps quiet nerve activity and plays a role in regulating sleep.  

• Connecting the gut and sleep: Pistachios provide fiber and polyphenols that gut microbes can break down into compounds that may influence communication between the gut and brain, including signaling involved in sleep regulation. Researchers are exploring whether these interactions could be another way pistachios influence sleep. 

How much tryptophan do pistachios provide?  

A one-ounce serving of pistachios provides about 71 milligrams of tryptophan, roughly 20% of the daily amount recommended for a 154-pound adult.^ Tryptophan is an essential amino acid the body uses to make serotonin, a brain chemical involved in sleep regulation, and melatonin, the hormone that helps regulate the sleep–wake cycle. 

Pistachios also provide vitamin B6 and magnesium, which help the body convert tryptophan along the pathway to serotonin and melatonin. Together, this combination is one reason researchers are interested in studying whole pistachios and sleep. 

Why the whole pistachio matters 

Most nutrition-and-sleep research has examined individual nutrients, extracts or supplements. Pistachios bring several of these components together naturally in one food, creating an opportunity to study how they may work together rather than in isolation. This natural structure, how nutrients and plant compounds are packaged together and interact within a food, is known as the food matrix, and in this context – the pistachio food matrix.  

“Pistachios are compelling for sleep research because they bring together several nutrients and plant compounds connected to sleep physiology within one whole food,” said Marie-Pierre St-Onge, PhD, the review’s senior and corresponding author and director of the Center of Excellence for Sleep and Circadian Research at Columbia University Irving Medical Center. “Rather than focusing on a single ‘sleep nutrient,’ this review provides a rationale for studying how the complete pistachio food matrix may affect sleep-related pathways.” 

As part of the review, researchers assessed laboratory studies that simulated digestion and fermentation of pistachios to explore how the pistachio food matrix may also influence how and when pistachio components become available to the body. Findings demonstrated that gut microbes can ferment pistachio fiber, transform its polyphenols and contribute to a longer release of phytomelatonin from pistachios. 

These findings suggest that researchers should study whole pistachios rather than nutrients or supplements in isolation, because nutrients may behave differently when consumed as part of the pistachio food matrix. 

Do pistachios improve sleep? 

The authors of this review concluded that pistachios could represent a promising wholefood intervention for improving sleep due to their unique combination of nutrients and bioactives, and map a clear path to additional research needed.  

The authors call for randomized controlled trials examining whole-pistachio consumption, dose–response relationships, melatonin levels, sleep outcomes and the bioavailability of key compounds. They also recommend investigating whether pistachio variety, growing conditions and processing influence the nutrient and bioactive content of pistachios. 

 “Well-designed human trials can help us determine whether the unique combination of nutrients and bioactive compounds in the pistachio food matrix produces measurable changes in melatonin, sleep quality, sleep duration or other sleep outcomes,” explains Dr. St-Onge. 

Taking statins is linked to a lower risk of developing glaucoma

 Taking statins is linked to a lower risk of developing glaucoma and a reduced chance of it getting worse, suggest the findings of research published online in the British Journal of Ophthalmology.

People who already have glaucoma who are taking statins appear less likely to need stronger treatments like extra eye drops or surgery to keep it under control, the US study finds.

Glaucoma, a leading cause of irreversible blindness, is caused by permanent damage to the optic nerve.

Statins are prescribed to lower cholesterol levels but studies have indicated that they may also prevent or slow nerve cell death. Their potential role in preventing or slowing down glaucoma is poorly understood.

To strengthen the evidence base, researchers searched a large global database covering 165 million individuals.

They compared more than 210 000 people who had a record of statin use between August 2006 and August 2026 with a matched control group of 210 000 people who had no record of using statins. Individuals in both groups had to have a recorded ophthalmological follow up.

Statin use was associated with a 15% lower risk of developing open angle glaucoma, the researchers found.

At five years, there were 4771 new diagnoses of glaucoma in the statin group (2.3%) and 5491 in the control group (2.6%).

In a separate analysis, more than 30 000 individuals with glaucoma who were taking statins were compared with almost 250 000 individuals with glaucoma who were not taking statins.

Statins were linked to a lower risk of the individual progressing to need glaucoma surgery or other treatment.

At five years, statin use was associated with a 36% lower risk of incisional glaucoma surgery and a 55% reduced risk of minimally invasive glaucoma surgery (MIGS) - a keyhole procedure to lower the intraocular pressure in the eye.

Statins were also associated with a 60% lower risk of selective laser trabeculoplasty (SLT) - a procedure that lowers the pressure in the eye by using laser pulses. There was also a 12% reduced risk of eye drops to reduce the pressure in the eye linked to statin use.

After 10 years, statin use continued to be associated with a lower risk of incision glaucoma surgery, MIGS, SLT, and use of eye drops, the researchers found.

This is an observational study and as such, no firm conclusions can be drawn about cause and effect.

Another limitation of the study is that the researchers did not have access to individual patient data, including intraocular pressure measurements or surgical details

This means they were unable to determine whether surgery was performed due to increased disease severity or because the patient was not adhering to treatment. 

Nevertheless, they say their findings add to the growing literature about the neuroprotective effect of statins. Prospective randomised trials are now needed to better understand the effects of statin use on glaucoma incidence and treatment, they add.

“Our findings suggest that statin usage is associated with both lower incidence of primary open-angle glaucoma as well as decreased treatment escalation, “the researchers say.

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Dangers in consuming raw milk, dairy products

 -Unpasteurized milk, cheese and other “raw” dairy products are unsafe to drink or eat, especially for young children and those who are pregnant or breastfeeding, according to updated guidance from the American Academy of Pediatrics.

The AAP renews its call for a ban on the sale and distribution of raw milk and dairy products, including raw cheeses, because they increase the risk of life-threatening infections. Claims that raw milk provides superior health benefits are not supported by scientific evidence.

The statement, “Consumption of Unpasteurized (Raw) Milk and Milk Products by Pregnant People and Children,” is published in the November 2026 Pediatrics (published online Oct. 5). The policy statement, written by the Committee on Infectious Diseases and the Committee on Nutrition, will be featured during a Oct. 5 presentation at the AAP 2026 National Conference & Exhibition in San Diego.

The updated guidance also highlights emerging evidence that H5N1, or highly pathogenic avian influenza, may represent a new and potentially serious risk associated with raw milk.  Research suggests the virus can be transmitted from infected dairy cattle into milk, where it can reach high concentrations and remain detectable in refrigerated raw milk for up to five weeks.

“Nearly half of illnesses caused by raw dairy consumption occur in people under age 20 –  and a significant share of those cases are in children under 5,” said Adam J. Ratner, MD, MPH, FAAP, lead author. “These illnesses can be severe and lead to life-threatening complications. Pasteurization – a safe, effective process of heating and cooling milk before consumption that has been used for more than a century – dramatically reduces the risks without taking away the nutritional value families rely on.”

Dr. Ratner will discuss the policy during a “Meet the Red Book session” from 8-10 a.m.  Monday morning at the San Diego Convention Center, Room 6A.

Policy statements created by AAP are written by medical experts, reflect the latest evidence in the field, and go through several rounds of peer review before being approved by the AAP Board of Directors and published in Pediatrics. This policy statement updates guidance last provided in 2014 and reaffirmed in 2025.

Despite well-documented health risks, the sale and distribution of raw milk products remain legal in at least 27 states. Raw milk is milk obtained from cows, goats or sheep that has not undergone pasteurization, the process of heating milk to eliminate harmful bacteria and other pathogens.

During the 2024 U.S. dairy outbreak, infectious H5N1 virus was detected in nearly one-quarter of raw milk samples in affected areas. While there are no confirmed human cases of H5N1 infection from consuming raw milk to date, it remains a credible, emerging threat.

Unpasteurized milk is already a well-documented source of serious pathogens including Listeria, E. coli, Salmonella, Campylobacter, and Brucella. These infections can lead to hospitalization, life-threatening illness, miscarriage, and death, particularly in young children, pregnant people, and those with weakened immune systems.

Those who are pregnant face especially high risks from foodborne infections. The incidence of listeriosis, for example, is estimated to be 12 to 14 times higher during pregnancy than in the general population. Infection can lead to miscarriage, stillbirth, premature delivery or severe illness in newborns.

"Parents may choose raw milk because they have heard it is healthier or more natural, but the scientific evidence tells a different story," said Mark R. Corkins, MD, FAAP, co-author of the policy statement. "Pasteurized dairy products provide the same essential nutrients without exposing children and families to preventable infections from dangerous bacteria and viruses. For infants, children and pregnant people, pasteurized dairy products are clearly the safest choice."

Resources include:

Raw Milk: What Parents Need to Know About the Risk - HealthyChildren.org

Daily peanut consumption beneficially affects brain

 

A study from the Institute of Nutrition and Translational Research in Metabolism (NUTRIM) at Maastricht University Medical Center, Maastricht, Netherlands, has found that longer-term consumption of unsalted, skin-roasted peanuts can beneficially affect insulin responsiveness in the brains of older adults. The findings were recently published online in the international, peer-reviewed journal Food & Function.

Insulin acts as a vital signaling molecule in the brain that supports the growth and survival of nerve cells  and communication between them, all of which are important for memory and may help protect against Alzheimer's disease. The study documented that, after a 16-week course of peanut consumption, brain insulin responsiveness was beneficially affected in a cluster in the right hemisphere, encompassing parts of the lingual gyrus, hippocampus and parahippocampal and posterior cingulate gyri, which are brain regions involved in memory.

“The hormone insulin plays an important role in the brain, where it supports memory and other cognitive processes. As people age, the brain may become less responsive to insulin, which has been linked to age-related cognitive decline,” says Dr. Peter Joris, the study’s senior author and an associate professor in the Department of Nutrition and Movement Sciences, NUTRIM, Maastricht University Medical Center. “Our study found that daily peanut consumption beneficially affected insulin responsiveness in memory-related brain regions in older adults. These findings suggest that enhanced regional brain insulin responsiveness may contribute to the cognitive benefits of unsalted, skin-roasted peanut intake.”

The NUTRIM study involved 31 healthy older adults who ranged in age from 60-75 and consumed 60 grams (approximately two servings) of peanuts daily for 16 weeks. It was a randomized, controlled crossover trial – a strong clinical research design.

In 2025, Joris found that the 16-week peanut intervention increased global cerebral blood flow (CBF) by 3.6% and verbal memory by 5.8%. CBF is an important physiological marker of brain vascular function and refers to the amount of blood that flows through the brain, delivering oxygen and nutrients that are essential for maintaining brain health. These findings were published in the peer-reviewed journal Clinical Nutrition.

The NUTRIM study is unique because it combined a well-controlled, longer-term dietary intervention with advanced brain imaging techniques, specifically arterial spin labeling magnetic resonance imaging (ASL-MRI), to investigate the effects of daily peanut consumption on brain health. Brain insulin responsiveness was assessed from changes in regional CBF after intranasal insulin administration. Intrahepatic lipid (IHL) content was quantified using abdominal MRI. Cognitive performance was evaluated using the Cambridge Neuropsychological Test Automated Battery (CANTAB).

“Multiple nutrients present in peanuts, including unsaturated fats, dietary fiber, vitamins and minerals and bioactive phytochemicals, could potentially contribute to the observed brain benefits,” says Joris. “Peanuts are also a good source of plant-based protein and are especially rich in L-arginine. L-arginine is a key precursor of nitric oxide (NO), which has been reported to facilitate learning and memory performance.”

NUTRIM Study Details

Participants were given premeasured packets of skin-roasted peanuts during the peanut intervention period and directed to consume the peanuts in the morning or afternoon. They were allowed to eat the daily amount all at once, spread it out over the day or add the peanuts to their meals. During the control period, participants did not consume peanuts. After 16 weeks, participants switched to the other study period to further assess the effects of peanut consumption versus no peanuts on brain health.