Mediterranean diet ingredient may extend life
Olive oil in the diet may also help mitigate aging-related diseases
February 21, 2020
Science Daily/University of Minnesota Medical School
Researchers at the University of Minnesota Medical School discover a potential new way in which diet influences aging-related diseases.
Doug Mashek, PhD, a professor in the Departments of Medicine and Biochemistry, Molecular Biology and Biophysics, leads a team of researchers who discovered that olive oil in the Mediterranean diet may hold the key to improving lifespan and mitigating aging-related diseases. Over the last eight years, with the help of multiple grants from the National Institutes of Health, their research findings were recently published in Molecular Cell.
Early studies on the diet suggested red wine was a major contributor to the health benefits of the Mediterranean diet because it contains a compound called resveratrol, which activated a certain pathway in cells known to increase lifespan and prevent aging-related diseases. However, work in Mashek's lab suggests that it is the fat in olive oil, another component of the Mediterranean diet, that is actually activating this pathway.
According to Mashek, merely consuming olive oil is not enough to elicit all of the health benefits. His team's studies suggest that when coupled with fasting, limiting caloric intake and exercising, the effects of consuming olive oil will be most pronounced.
"We found that the way this fat works is it first has to get stored in microscopic things called lipid droplets, which is how our cells store fat. And then, when the fat is broken down during exercising or fasting, for example, is when the signaling and beneficial effects are realized," Mashek said.
The next steps for their research are to translate it to humans with the goal of discovering new drugs or to further tailor dietary regimens that improve health, both short-term and long-term.
"We want to understand the biology, and then translate it to humans, hopefully changing the paradigm of healthcare from someone going to eight different doctors to treat his or her eight different disorders," Mashek said. "These are all aging-related diseases, so let's treat aging."
https://www.sciencedaily.com/releases/2020/02/200221125120.htm
For older adults, a better diet may prevent brain shrinkage
May 16, 2018
Science Daily/American Academy of Neurology
People who eat a diet rich in vegetables, fruit, nuts and fish may have bigger brains, according to a new study.
"People with greater brain volume have been shown in other studies to have better cognitive abilities, so initiatives that help improve diet quality may be a good strategy to maintain thinking skills in older adults," said study author Meike W. Vernooij, MD, PhD, of the Erasmus University Medical Center in Rotterdam, the Netherlands. "More research is needed to confirm these results and to examine the pathways through which diet can affect the brain."
The study included 4,213 people in the Netherlands with an average age of 66 who did not have dementia.
Participants completed a questionnaire asking how much they ate of nearly 400 items over the past month. Researchers looked at diet quality based on the Dutch dietary guidelines by examining intake of foods in the following groups: vegetables, fruit, whole grain products, legumes, nuts, dairy, fish, tea, unsaturated fats and oils of total fats, red and processed meat, sugary beverages, alcohol and salt. Researchers ranked the quality of diet for each person with a score of zero to 14. The best diet consisted of vegetables, fruit, nuts, whole grains, dairy and fish, but a limited intake of sugary drinks. The average score of participants was seven.
All participants had brain scans with magnetic resonance imaging to determine brain volume, the number of brain white matter lesions and small brain bleeds. The participants had an average total brain volume of 932 milliliters.
Information was also gathered on other factors that could affect brain volumes, such as high blood pressure, smoking and physical activity.
Researchers found after adjusting for age, sex, education, smoking and physical activity that a higher diet score was linked to larger total brain volume, when taking into account head size differences. Those who consumed a better diet had an average of two milliliters more total brain volume than those who did not. To compare, having a brain volume that is 3.6 milliliters smaller is equivalent to one year of aging.
Diet was not linked to brain white matter lesions or small brain bleeds.
For comparison, researchers also assessed diet based on the Mediterranean diet, which is also rich in vegetables, fish and nuts, and found brain volume results were similar to those who adhered closely to Dutch dietary guidelines.
Vernooij said the link between better overall diet quality and larger total brain volume was not driven by one specific food group, but rather several food groups.
"There are many complex interactions that can occur across different food components and nutrients and according to our research, people who ate a combination of healthier foods had larger brain tissue volumes," Vernooij said.
She noted that because the study was a snapshot in time, it does not prove that a better diet results in a larger brain volume; it only shows an association.
Limitations of the study include that diet was self-reported and relied on someone's ability to remember what they ate over one month, and the study was conducted in a Dutch population and therefore other populations may not have similar results.
https://www.sciencedaily.com/releases/2018/05/180516162539.htm
Can a Mediterranean diet pattern slow aging?
March 30, 2018
Science Daily/The Gerontological Society of America
A series of six articles finds new correlations between a Mediterranean diet and healthy aging outcomes -- while also underscoring the need for careful approaches to the use of data in order to measure the diet's potential benefits.
Among their findings, the new articles report on underlying mechanisms of the diet; the positive relationship between the diet and physical and cognitive function; the value of taking a coenzyme Q10 supplement while adhering to the diet; and the role of the diet in reducing inflammation. But in several of the studies, the level of benefit was dependent on how adherence to the diet was measured.
"Greater clarity on how this diet is defined, in both interventions and observational studies, will be critical in the aim of achieving a consensus on how to optimally apply this dietary pattern towards maximizing healthy aging," state Michelle A. Mendez, PhD, and Journals of Gerontology: Medical Sciences Editor-in-Chief Anne B. Newman, MD, FGSA, in an opening editorial.
Hallmarks of the Mediterranean diet include: a variety of minimally processed whole grains and legumes as the staple food; plenty of a huge diversity of fresh vegetables consumed on a daily basis; fresh fruits as the typical daily dessert; cold pressed extra-virgin olive oil, nuts, and seeds as the principal source of fat; moderate consumption of fish; dairy products consumed in low amounts; red and processed meat consumed in very low frequency and amounts; and wine consumed in low to moderate amounts only with meals.
There are a number of scales used to measure adherence to the diet. One of the journal's studies, conducted by researchers at the University of Paris 13, found that among test subjects, higher numbers on the Literature-based Adherence Score to the Mediterranean Diet were associated with higher odds of meeting certain healthy aging criteria. Similar results were found with another index, the Mediterranean Diet Score; however, use of the Mediterranean Diet Scale yielded a weaker correlation. In another study by researchers at the Autonomous University of Madrid, closer adherence to the diet was associated with a lower likelihood of physical function impairment in older adults, although in this case using the Mediterranean Diet Adherence Screener provided more significant results than the Mediterranean Diet Score.
The exact mechanism by which an increased adherence to the diet exerts its favorable effects is still unknown to scientists. However, writing in one of the new articles, researchers from Washington University in St. Louis state there is accumulating evidence of five important adaptations induced by the Mediterranean dietary pattern. These include lipid lowering; protection from oxidative stress and inflammation; modification of growth factors that can promote cancer; inhibition of nutrient sensing pathways by amino acid restriction and gut microbiota-mediated production of metabolites.
https://www.sciencedaily.com/releases/2018/03/180330145322.htm