AHA: Adding Omega-3 Fatty Acids Does Not Cut High CV Risk

In continuation of my update on omega-3 fatty acids

A carboxylic acid formulation of eicosapentaenoic acid and docosahexaenoic acid (omega-3 CA) does not improve outcomes among statin-treated patients at high cardiovascular risk, according to a study published online Nov. 15 in the Journal of the American Medical Association to coincide with the American Heart Association Scientific Sessions 2020, held virtually from Nov. 13 to 17.

Stephen J. Nicholls, M.B.B.S., Ph.D., from Monash University in Melbourne, Australia, and colleagues conducted a double-blind trial comparing omega-3 CA to corn oil in 13,078 statin-treated patients with high cardiovascular risk, hypertriglyceridemia, and low high-density lipoprotein cholesterol from 675 academic and community hospitals in 22 countries. Participants were randomly assigned in a 1:1 ratio to either 4 g/day omega-3 CA or corn oil (6,539 to each) in addition to usual background therapies, including statins.

The trial was halted prematurely based on an interim analysis indicating low probability of clinical benefit of omega-3 CA, when 1,384 patients had experienced a primary end-point event. The researchers found that the primary end point (composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina requiring hospitalization) occurred in 12.0 and 12.2 percent of those treated with omega-3 CA and corn oil, respectively (hazard ratio, 0.99; 95 percent confidence interval, 0.90 to 1.09; P = 0.84).

"These findings do not support use of this omega-3 fatty acid formulation to reduce major adverse cardiovascular events in high-risk patients," the authors write.

Several authors disclosed financial ties to pharmaceutical companies, including AstraZeneca, which funded the study.

AHA: Adding Omega-3 Fatty Acids Does Not Cut High CV Risk  

Walnuts may slow cognitive decline in at-risk elderly: Two-year study examined walnut consumption among study groups in California and Spain

In continuation of my update on Walnuts

Eating walnuts may help slow cognitive decline in at-risk groups of the elderly population, according to a study conducted by researchers in California and Spain.

The Walnuts and Healthy Aging Study, published this month in The American Journal of Clinical Nutrition, found that walnut consumption by healthy, elderly adults had little effect on cognitive function over two years, but it had a greater effect on elderly adults who had smoked more and had a lower baseline neuropsychological test scores.

The study examined nearly 640 free-living elders in Loma Linda, California, USA, and in Barcelona, Catalonia, Spain. For two years, the test group included walnuts in their daily diet, and the control group abstained from walnuts.

Walnuts contain omega-3 fatty acids and polyphenols, which have previously been found to counteract oxidative stress and inflammation, both of which are drivers of cognitive decline.

Joan Sabaté, MD, DrPH, professor of nutrition and epidemiology at Loma Linda University School of Public Health and the study's principal investigator, said this was the largest and most well-controlled trial ever conducted on the effects of nuts on cognition.

"While this was a minor result, it could lead to better outcomes when conducted over longer periods of time," Sabaté said. "Further investigation is definitely warranted based on our findings, especially for disadvantaged populations, who may have the most to gain from incorporating walnuts and other nuts into their diet."

Sabaté and his research team at Loma Linda University were the first to discover the cholesterol-lowering effect of nut consumption -- specifically walnuts -- with lowering blood cholesterol. Findings were first published in the New England Journal of Medicine in 1993.

Subsequently, findings from Loma Linda University researchers have linked nut consumption to lower risk of cardiovascular diseases.

The Walnuts and Healthy Aging Study was funded by a grant from the California Walnut Commission, which had no input in the study design, data collection, analyses, or writing and submission of the manuscript.

https://news.llu.edu/research/walnuts-may-slow-cognitive-decline-risk-elderly

Infant Omega-3 Supplementation Tied to Decreased Waist Size

In continuation of my update on Omega-3 fatty acids

Omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) supplementation in infancy is associated with reduced insulin concentrations and insulin resistance in boys and reduced waist circumference in both sexes at age 5 years, according to a study published online June8 in Pediatrics.

Valene H.L. See, Ph.D., from the Royal Perth Hospital in Australia, and colleagues randomly assigned 420 infants to a daily supplement of n-3 LCPUFA or olive oil (control) from birth to 6 months. Growth, body composition, and cardiometabolic risk factors were evaluated at 5 years of age.

The researchers found that infants who received n-3 LCPUFA had a smaller waist circumference at 5 years (coefficient, 1.1 cm), which remained significant after adjusting for confounders (coefficient, 0.8 cm). Boys who received n-3 LCPUFA supplementation had a 21 percent reduction in insulin concentrations and a 22 percent reduction in insulin resistance versus the control group. At birth, 2.5 years, and 5 years, there were no other differences in growth and cardiometabolic risk factors between the groups.

"Longer-term follow-up of the cohort is warranted to determine whether these differences are maintained into adolescence," write the authors

Infant Omega-3 Supplementation Tied to Decreased Waist Size..

In continuation of my update on Omega-3 fatty acids

Omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) supplementation in infancy is associated with reduced insulin concentrations and insulin resistance in boys and reduced waist circumference in both sexes at age 5 years, according to a study published online June8 in Pediatrics.

Valene H.L. See, Ph.D., from the Royal Perth Hospital in Australia, and colleagues randomly assigned 420 infants to a daily supplement of n-3 LCPUFA or olive oil (control) from birth to 6 months. Growth, body composition, and cardiometabolic risk factors were evaluated at 5 years of age.

The researchers found that infants who received n-3 LCPUFA had a smaller waist circumference at 5 years (coefficient, 1.1 cm), which remained significant after adjusting for confounders (coefficient, 0.8 cm). Boys who received n-3 LCPUFA supplementation had a 21 percent reduction in insulin concentrations and a 22 percent reduction in insulin resistance versus the control group. At birth, 2.5 years, and 5 years, there were no other differences in growth and cardiometabolic risk factors between the groups.

"Longer-term follow-up of the cohort is warranted to determine whether these differences are maintained into adolescence," write the authors

New trial to test if omega-3 capsules can stop secondary liver cancer recurrence after surgery

In continuation of my update on  omega-3  

A new clinical trial from the University of Leeds is testing omega-3 capsules in patients who have bowel cancer which has spread to the liver, to see if it can stop the cancer returning after surgery.

Promising results in an earlier smaller trial showed that providing patients with 2g per day of the omega-3, called EPA, for around a month prior to surgery led to a 30 percent increase in survival after 18 months.

Researchers at the University of Leeds are building on this past work by launching a larger clinical trial, recruiting 450 patients who are undergoing surgery for bowel cancer which has spread to the liver, known as secondary liver cancer. The first Leeds patient has just been recruited to the trial in Leeds Teaching Hospitals NHS Trust.

The trial is investigating whether a highly purified form of the omega-3 EPA could be an effective way to stop cancer returning after surgery, and is funded by Yorkshire Cancer Research.

Professor Mark Hull, from the University of Leeds' Institute of Biomedical and Clinical Sciences and Leeds Teaching Hospitals, is leading the trial, which involves several hospitals from around the country, including Leeds, Sheffield and Southampton.

Professor Hull said: "Secondary liver cancer is the leading cause of death for patients with bowel cancer, as the cancer spreads from the bowels to the liver, so it is vitally important that we improve our ability to stop secondary liver spread.

"After undergoing surgery to remove secondary liver cancer, 50 to 75 percent of patients develop a recurrence of the disease after two years, so we are investigating an intervention that may help stop the cancer returning.

"Given the minimal side-effects of omega-3 capsules and how relatively cost-effective they are compared with other more expensive anti-cancer treatments, this intervention could one day be used widely to improve survival from advanced bowel cancer."

Bowel cancer is the fourth most common cancer in the UK, with more than 41,000 new cases diagnosed every year.

While survival has more than doubled in the last 40 years, more than half of patients with the disease experience recurrence elsewhere in the body, most commonly the liver or lungs, which is known as secondary, advanced or metastatic bowel cancer.

Omega-3 fatty acids are found mainly in fish oils and are already known to be beneficial for other health conditions including heart problems.

Dr Kathryn Scott, Chief Executive at Yorkshire Cancer Research which is funding the trial, said: "This is a cheap and potentially powerful new way to help treat bowel cancer that, if successful, could have a huge impact.

"As well as having a potential impact on treatment, the trial will provide an opportunity for patients to take part in a pioneering study. It is well proven that patients do better in a research-rich environment."

The EPA formulation, known as icosapent ethyl and marketed as a prescription product called Vascepa® in the United States, and the placebo, have been donated free of charge by Amarin Corporation plc.

Omega fatty acid supplements may improve ASD symptoms in toddlers born preterm, study shows

In continuation of my update on omega fatty acids

Researchers from Nationwide Children's Hospital have shown that omega fatty acid supplements may improve autism spectrum disorder symptoms in toddlers who were born very preterm (more than 11 weeks early). The study was published recently in the Journal of Nutrition.

"The trial had two goals. First, we wanted to confirm the feasibility of a large study of toddlers born very preterm and exhibiting symptoms often seen with ASD. Second, we wanted to see what the effects of omega fatty acids would be on parent-reported ASD symptoms and related behaviors," says Sarah Keim, Ph.D., lead author on the study and principal investigator in the Center for Biobehavioral Health in The Research Institute at Nationwide Children's.

Dr. Keim and her team conducted a study where 31 toddlers who were born prematurely participated. For 3 months, half of them took a daily dietary supplement that contained a special combination of omega-3 and omega-6 fatty acids, and the other half took a placebo, although families were unaware of which they received to make the study rigorous.

The group that took the daily omega fatty acid supplement exhibited a greater reduction in ASD symptoms than those who took the placebo, according to ratings provided by the children's parents.

"We found clinically significant improvements in ASD symptoms in the treatment group, although the benefits were confined to one measure we used," explains Dr. Keim. "We need to do a larger trial to further understand the potential impacts on a larger group of children."

The researchers suggest that observed benefits of omega fatty acid supplementation could be due to the role of these nutrients in inflammation in the body. ASD is generally considered a neuroinflammatory condition, and influencing inflammation through nutritional supplementation could improve behaviors in children with ASD symptoms.

Researchers hope that by giving omega fatty acids to children early when they first show symptoms and the brain is still actively developing may help them long-term.

"Currently, no medications are available to help children born prematurely with the developmental delays and behavior problems they often experience. For very young children, the medications that physicians sometimes try tend to have many side effects. And we don't know what effect those medications have on brains that are still developing," says Dr. Keim. "If using omega fatty acid supplementation helps, it would have a really huge impact for these kids."

Dr. Keim and her team plan to expand the work in a full-scale trial in the future. They recently received a grant from the National Institutes of Health to study the effect of omega fatty acids in children ages 2-6 year who have ASD.

Ref : https://academic.oup.com/jn/article-abstract/148/2/227/4913038?redirectedFrom=fulltext

Omega fatty acid supplements may improve ASD symptoms in toddlers born preterm, study shows

Omega-3 and Omega-6 fatty acid intake may affect lupus outcomes

 

In continuation of my update on omega fatty acids

Higher intake of omega-3 fatty acids was associated with better sleep quality and a decrease in depressive symptoms in lupus patients, among other patient-reported outcomes, according to new research findings presented this week at the 2017 ACR/ARHP Annual Meeting in San Diego. 

Lupus is a chronic (long-term) inflammatory autoimmune disease in which an unknown trigger causes the body's immune system to attack its own healthy tissues. The most common type of lupus is systemic lupus erythematosus (SLE), a complex, multiple symptom disease that can cause inflammation, pain and damage to various parts of the body. While anyone can develop lupus, it occurs 9-10 times more often in women than in men, and is 2-3 times more common among women of color.

Omega fatty acids have an effect on inflammation in the body, with omega-3 fatty acids generally acting as an anti-inflammatory and omega-6 fatty acids acting as a pro-inflammatory. Western diets are often much higher in omega-6fatty acids, and they are suspected to contribute to chronic diseases.

While small studies show an association between omega-3 supplementation and reduced disease activity in lupus patients. Researchers at the University of Michigan in Ann Arbor examined their impact on patient-reported outcomes, or PROs. They performed a population-based, cross-sectional study to look for a possibleassociation between dietary intake of omega-3 and omega-6 fatty acidsand PROs in lupus patients. Data from the Michigan Lupus Epidemiology & Surveillance (MILES) program was used.

"Western diets are thought to contribute to an increase in people with chronic conditions including autoimmune diseases. Many small studies found that omega-3 supplementation was associated with an improvement in disease activity in SLE patients, but no studies have looked at omega-3 exposure through diet or its impact on PROs," said Prae Charoenwoodhipong, MS, a graduate student in the Department of
Nutrition Science at the University of Michigan School of Public Health in Ann Arbor. "Also, very few studies have looked at the impact of omega-6, an inflammatory fatty acid that is very common in U.S. diets. According to rheumatologists I've worked with, patients with SLE are always asking about what they might be able to do with supplements or their diet to help improve their health."

Omega-3 and Omega-6 fatty acid intake may affect lupus outcomes

Taking omega-3 supplements during pregnancy can reduce risk of childhood asthma by one third

In continuation of my update on omega 3 fatty acids

Taking certain omega-3 fatty acid supplements during pregnancy can reduce the risk of c

hildhood asthma by almost one third, according to a new study from the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) and the University of Waterloo.

The study, published in the New England Journal of Medicine, found that women who were prescribed 2.4 grams of long-chain omega-3 supplements during the third trimester of pregnancy reduced their children's risk of asthma by 31 per cent. Long-chain omega-3 fatty acids, which include eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are found in cold water fish, and key to regulating human immune response.

"We've long suspected there was a link between the anti-inflammatory properties of long-chain omega-3 fats, the low intakes of omega-3 in Western diets and the rising rates of childhood asthma," said Professor Hans Bisgaard of COPSAC at the Copenhagen University Hospital. "This study proves that they are definitively and significantly related."

The study used rapid analytical techniques developed and performed at the University of Waterloo to measure levels of EPA and DHA in pregnant women's blood. The University of Waterloo is one of a few laboratories in the world equipped to run such tests.

"Measuring the levels of omega-3 fatty acids in blood provides an accurate and precise assessment of nutrient status," said Professor Ken Stark, Canada Research Chair in Nutritional Lipidomics and professor in the Faculty of Applied Health Sciences at Waterloo, who led the testing. "Our labs are uniquely equipped to measure fatty acids quickly, extremely precisely, and in a cost-efficient manner."

The testing also revealed that women with low blood levels of EPA and DHA at the beginning of the study benefitted the most from the supplements. For these women, it reduced their children's relative risk of developing asthma by 54 per cent.

"The proportion of women with low EPA and DHA in their blood is even higher in Canada and the United States as compared with Denmark. So we would expect an even greater reduction in risk among North American populations," said Professor Stark. "Identifying these women and providing them with supplements should be considered a front-line defense to reduce and prevent childhood asthma."

 

Researchers analyzed blood samples of 695 Danish women at 24 weeks' gestation and one week after delivery. They then monitored the health status of each participating child for five years, which is the age asthma symptoms can be clinically established.

"Asthma and wheezing disorders have more than doubled in Western countries in recent decades," said Professor Bisgaard. "We now have a preventative measure to help bring those numbers down."

Currently, one out of five young children suffer from asthma or a related disorder before school age.

https://uwaterloo.ca/news/news/omega-3-supplements-can-prevent-childhood-asthma

Supplement of polyunsaturated fatty acids may improve reading skills in children

Supplement of omega-3 and omega-6 fatty acids may improve reading skills of mainstream schoolchildren, according to a new study from Sahlgrenska Academy, at the University of Gothenburg, Sweden. Children with attention problems, in particular, may be helped in their reading with the addition of these fatty acids.

The study included 154 schoolchildren from western Sweden in grade 3, between nine and ten years old. The children took a computer-based test (known as the Logos test) that measured their reading skills in a variety of ways, including reading speed, ability to read nonsense words and vocabulary.

The children were randomly assigned to receive either capsules with omega-3 and omega-6, or identical capsules that contained a placebo (palm oil) for 3 months. The children, parents and researchers did not learn until the study was completed which children had received fatty acids and which had received the placebo. After three months, all children received real omega-3/6 capsules for the final three months of the study.

"Even after three months, we could see that the children's reading skills improved with the addition of fatty acids, compared with those who received the placebo. This was particularly evident in the ability to read a nonsense word aloud and pronounce it correctly (phonologic decoding), and the ability to read a series of letters quickly (visual analysis time)," says Mats Johnson, who is chief physician and researcher at the Gillberg Neuropsychiatry Centre at Sahlgrenska Academy, University of Gothenburg.

No children diagnosed with ADHD were included in the study, but with the help of the children's parents, the researchers could identify children who had milder attention problems. These children attained even greater improvements in several tests, including faster reading already after three months of receiving fatty acid supplements.

Polyunsaturated fats important for the brain

Polyunsaturated fats and their role in children's learning and behavior is a growing research area.

"Our modern diet contains relatively little omega-3, which it is believed to have a negative effect on our children when it comes to learning, literacy and attention," says Mats Johnson. "The cell membranes in the brain are largely made up of polyunsaturated fats, and there are studies that indicate that fatty acids are important for signal transmission between nerve cells and the regulation of signaling systems in the brain."

Previous studies in which researchers examined the effect of omega-3 as a supplement for mainstream schoolchildren have not shown positive results, something Mats Johnson believes may depend on how these studies were organized and what combination and doses of fatty acids were used. This is the first double-blind, placebo-controlled study showing that omega-3/6 improves reading among mainstream schoolchildren.

"Our study suggests that children could benefit from a dietary supplement with a special formula. To be more certain about the results, they should also be replicated in other studies," says Mats Johnson.

Supplement of polyunsaturated fatty acids may improve reading skills in children

Optimal doses of omega-3 fatty acids appear to improve outcomes from traumatic brain injury

In continuation of my update on omega-3 fatty acids

The treatment of concussions and traumatic brain injury (TBI) is a clinical challenge. Clinical studies thus far have failed to identify an effective treatment strategy when a combination of targets controlling aspects of neuroprotection, neuroinflammation, and neuroregeneration is needed. According to emerging science and clinical experience, aggressive intake of omega-3 fatty acids (n-3FA) seems to be beneficial to TBI, concussion, and post-concussion syndrome patients. This research is presented in Concussions, Traumatic Brain Injury, and the Innovative Use of Omega-3s, a review article from the Journal of the American College of Nutrition, official publication of the American College of Nutrition.

Research suggests that early and optimal doses of omega-3 fatty acids (n-3FA) have the potential to improve outcomes from traumatic brain injury. The article reviews preclinical research and cites three brain injury case studies that resulted from a mining accident, a motor vehicle accident, and a drowning accident. Each instance showcased evidence of safety and tolerability, wherein the patients who sustained life-threatening brain injuries recovered brain health with the aid of omega-3 fatty acids (n-3FA).

Growing clinical experience by numerous providers is that the brain needs to be saturated with high doses of n-3FA in order for the brain to have the opportunity to heal. Without an optimal supply of omegas, healing is less likely to happen. It is well recognized that n-3FAs are not a drug and not a cure and every situation is different. Clinically, some patients respond better than others. However, there is no downside to providing optimal levels of nutrition in order to give a patient the best opportunity to regain as much function as possible following a TBI.

Article author Michael D. Lewis, a retired Army Colonel and physician, is the author of the highly anticipated book, When Brains Collide: What Every Athlete and Parent Should Know About the Prevention and Treatment of Concussions and TBI, that will be available on Amazon in September 2016. Dr. Lewis concludes, "n-3FA should be considered mainstream, conventional medicine, if conventional medicine can overcome its inherent bias against nutritional, nonpharmacological therapies."

Are Omega-3s Linked to Lower Risk for Fatal Heart Attack?

In continuation of my updates on omega-3 fatty acids

Regularly eating fish and other foods rich in omega-3 fatty acids may lower your risk of fatal heart disease, a new research review suggests.

"Our results lend support to the importance of fish and omega-3 consumption as part of a healthy diet," said senior study author Dr. Dariush Mozaffarian, dean of the Friedman School of Nutrition Science and Policy at Tufts University, in Boston.

"At a time when some but not other trials of fish oil supplementation have shown benefits, there is uncertainty about cardiovascular effects of omega-3s," Mozaffarian said in a university news release.

Fish are the main dietary sources of omega-3 fatty acids. Fatty fish, such as salmon, trout, anchovies, sardines and herring, are the richest source of these nutrients.

Walnuts, flaxseed oil, canola oil and some other seeds and nuts contain the plant-based omega-3 known as alpha-linolenic acid, according to the U.S. Department of Agriculture.

For the study, the researchers analyzed 19 studies from 16 countries that involved nearly 46,000 people. Of these people, nearly 8,000 suffered a first heart attack over time, which resulted in 2,781 deaths.

Plant-based and seafood-based omega-3s were not associated with a lower risk of non-fatal heart attacks. But they were linked with a roughly 10 percent lower risk of fatal heart attacks, although the study can't prove a direct cause-and-effect relationship.

"These new results, including many studies which previously had not reported their findings, provide the most comprehensive picture to date of how omega-3s may influence heart disease," said study leader Liana Del Gobbo, a postdoctoral research fellow at Stanford University School of Medicine. "Across these diverse studies, findings were also consistent by age, sex, race, presence or absence of diabetes, and use of aspirin or cholesterol-lowering medications."

Are Omega-3s Linked to Lower Risk for Fatal Heart Attack?  

Increase in EPA/DHA omega-3 intake linked to lower risk of all-cause mortality

A recent meta-analysis in Scientific Reports supports a link between EPA and DHA omega-3 intake and a reduced risk of death by any cause. The meta-analysis included 11 studies involving 371,965 participants and 31,185 death events, with a subset of the studies being used for different analyses.

DHA   EPA

In the analysis of n-3 LCPUFA intake, there was a 9% reduced risk of all-cause death associated with high versus low omega-3 intake. In the dose-response analysis, an increase in EPA/DHA intake of 300 mg/day was associated with a 6% lower risk of all-cause mortality. These findings suggest that both dietary and circulating n-3 LCPUFA are shown to be significantly associated with reduced risk of all-cause mortality.

According to study author Manfred Eggersdorfer, "The meta-analysis of 11 prospective observational studies demonstrates that each 1% increment of omega-3s in total fatty acids in blood may be associated with a 20% decrease in risk of all-cause mortality. This is an important finding for the potential contribution of adequate omega-3 intake to public health."

Walnuts may improve your colon health: Eating walnuts changes the gut microbiome and reduces cancer growth, study shows

In continuation of my update on walnuts  

A team of researchers from UConn Health and The Jackson Laboratory for Genomic Medicine found that mice that ate 7-10.5 percent of their total calories as walnuts developed fewer colon cancers. The effect was most pronounced in male mice, which had 2.3 times fewer tumors when fed walnuts as part of a diet similar to the typical American's. That's equivalent to a human eating about an ounce of walnuts a day.

"Our results show for the first time that walnut consumption may reduce colon tumor development," said Principal Investigator Dr. Daniel W. Rosenberg of UConn Health. "There is accumulating evidence that eating walnuts may offer a variety of benefits related to health issues like cancer. This study shows that walnuts may also act as a probiotic to make the colon healthy, which in turn offers protection against colon tumors."

Walnuts are packed with compounds known to be important nutritionally. They have the most polyunsaturated fatty acids of all the commonly eaten tree nuts, as well as the highest ratio of omega-3 to omega-6 fatty acids, and high levels of a form of Vitamin E with anti-cancer properties.

But walnuts are not merely the sum of their chemical parts, and it may be as a whole food that they pack the most significant anti-cancer punch against colon cancer, the third most common cancer in the world. Other studies have shown walnuts have promise warding off diseases connected to diet and lifestyle, including heart disease, diabetes and neurological disorders.

Rosenberg, a cancer researcher and professor of medicine at UConn Health and Dr. Masako Nakanishi, a research associate in the Center for Molecular Medicine at UConn Health tested the cancer prevention qualities of walnuts on mice fed two different diets. One group of mice ate a standard lab mouse chow, while the other group ate a chow that captured the nutritional profile of the typical American diet. Subsets of both groups were supplemented with walnuts.

Interestingly, male mice fed the Western diet fortified with 10.5 percent walnuts showed the greatest decrease in colon tumors compared with mice fed no walnuts.

To figure out why walnuts were beneficial, the UConn Health team collaborated with Dr. George Weinstock and colleagues at The Jackson Laboratory. Weinstock's lab took fecal samples from the mice and analyzed the communities of bacteria living in their digestive tracts. They found that walnut consumption tended to push the gut microbiome toward an ecology that was potentially protective against cancer. It's not clear exactly how this works, but there are clues. For example, previous research has shown that some gut bacteria digest fiber into compounds with anti-inflammatory properties that may reduce tumor initiation. The microbiome analyses also reflected interesting differences between male and female. Males on walnut-free diets tended to have less-diverse gut flora than females. Adding walnuts to the diets of male mice brought their microbiomes closer to those of female mice on either of the diets. Whether this change contributes to the protection seen in male mice remains to be determined.

Because the studies were done only in mice, more testing needs to be done in humans before walnuts can be unequivocally recommended as a cancer-prevention agent. Rosenberg's group is working with a nutritionist and surveying human colonoscopy patients about their diets as part of a longer term study in humans.

However, Rosenberg isn't waiting for the final word. Even right now, he says, "I try to eat walnuts every day."

Omega-3 fatty acids improve cognitive flexibility in older adults at risk of late-onset Alzheimer's disease

A study of older adults at risk of late-onset Alzheimer's disease found that those who consumed more omega-3 fatty acids did better than their peers on tests of cognitive flexibility -- the ability to efficiently switch between tasks -- and had a bigger anterior cingulate cortex, a brain region known to contribute to cognitive flexibility.

 

[alpha-linolenic acid (ALA), an essential omega-3 fatty acid, (18:3Δ9c,12c,15c, which means a chain of 18 carbons with 3 double bonds on carbons numbered 9, 12, and 15)].

The analysis suggests, but does not prove, that consuming DHA and EPA, two omega-3 fatty acids found in fish, enhanced cognitive flexibility in these adults in part by beefing up the anterior cingulate cortex, the researchers report in the journal Frontiers in Aging Neuroscience.

"Recent research suggests that there is a critical link between nutritional deficiencies and the incidence of both cognitive impairment and degenerative neurological disorders, such as Alzheimer's disease," said University of Illinois neuroscience, psychology, and speech and hearing science professor Aron Barbey, who led the study with M.D./Ph.D. student Marta Zamroziewicz. "Our findings add to the evidence that optimal nutrition helps preserve cognitive function, slow the progression of aging and reduce the incidence of debilitating diseases in healthy aging populations."

The researchers focused on aspects of brain function that are sometimes overlooked in research on aging, Zamroziewicz said. "A lot of work in cognitive aging focuses on memory, but in fact cognitive flexibility and other executive functions have been shown to better predict daily functioning than memory does," she said.

"Executive function" describes processes like planning, reasoning, paying attention, problem solving, impulse control and task switching.

"These functions tend to decline earlier than other cognitive functions in aging," Zamroziewicz said.

The new research built on previous studies that found associations between omega-3 fatty acid consumption, cognitive flexibility and the size of the anterior cingulate cortex.

"There's been some work to show that omega-3 fatty acids benefit cognitive flexibility, and there's also been work showing that cognitive flexibility is linked to this specific brain region, the anterior cingulate. But there's been very little work actually connecting these pieces," Zamroziewicz said.

The new study focused on 40 cognitively healthy older adults between the ages of 65 and 75 who are carriers of a gene variant (APOE e4) that is known to contribute to the risk of developing late-onset Alzheimer's disease.

The researchers tested participants' cognitive flexibility, measured levels of the fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) in their blood, and imaged their brains using MRI. Statistical analyses teased out the relationships between these factors.

"We wanted to confirm that higher omega-3 fatty acids related to better cognitive flexibility, and we did in fact see that," Zamroziewicz said. "We also wanted to confirm that higher omega-3 fatty acids related to higher volume in the anterior cingulate cortex, and we saw that. Finally, we were able to show that higher volume in the anterior cingulate cortex was an intermediary in the relationship between omega-3 fatty acids and cognitive flexibility."

 Docosahexaenoic acid

  Eicosapentaenoic acid

Omega-3 fatty acids improve cognitive flexibility in older adults at risk of late-onset Alzheimer's disease