Brain power with Mediterranean diet, nuts

Brain power with Mediterranean diet, nuts

Supplementing the plant-based Mediterranean diet with antioxidant-rich extra virgin olive oil or mixed nuts was associated with improved cognitive function in a study of older adults in Spain but the authors warn more investigation is needed, according to an article published online by JAMA Internal Medicine.

Emerging evidence suggests associations between dietary habits and cognitive performance. Oxidative stress (the body’s inability to appropriately detoxify itself) has long been considered to play a major role in cognitive decline. Previous research suggests following a Mediterranean diet may relate to better cognitive function and a lower risk of dementia. However, the observational studies that have examined these associations have limitations, according to the study background.

Emilio Ros, M.D., Ph.D., of the Institut d’Investigacions Biomediques August Pi Sunyer, Hospital Clinic, Barcelona, and Ciber Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, and coauthors compared a Mediterranean diet supplemented with olive oil or nuts with a low-fat control diet.

The randomized clinical trial included 447 cognitively healthy volunteers (223 were women; average age was nearly 67 years) who were at high cardiovascular risk and were enrolled in the Prevencion con Dieta Mediterranea nutrition intervention.

Of the participants, 155 individuals were assigned to supplement a Mediterranean diet with one liter of extra virgin olive oil per week; 147 were assigned to supplement a Mediterranean diet with 30 grams per day of a mix of walnuts, hazelnuts and almonds; and 145 individuals were assigned to follow a low-fat control diet.

The authors measured cognitive change over time with a battery of neuropsychological tests and they constructed three cognitive composites for memory, frontal (attention and executive function) and global cognition. After a median of four years of the intervention, follow-up tests were available on 334 participants.

At the end of the follow-up, there were 37 cases of mild cognitive impairment: 17 (13.4 percent) in the Mediterranean diet plus olive oil group; eight (7.1 percent) in the Mediterranean diet plus nuts group; and 12 (12.6 percent) in the low-fat control group. No dementia cases were documented in patients who completed study follow-up.

The study found that individuals assigned to the low-fat control diet had a significant decrease from baseline in all composites of cognitive function.

Compared with the control group, the memory composite improved significantly in the Mediterranean diet plus nuts, while the frontal and global cognition composites improved in the Mediterranean diet plus olive oil group. 

The authors note the changes for the two Mediterranean diet arms in each composite were more like each other than when comparing the individual Mediterranean diet groups with the low-fat diet control group.

“Our results suggest that in an older population a Mediterranean diet supplemented with olive oil or nuts may counter-act age-related cognitive decline. The lack of effective treatments for cognitive decline and dementia points to the need of preventive strategies to delay the onset and/or minimize the effects of these devastating conditions. 

The present results with the Mediterranean diet are encouraging but further investigation is warranted,” the study concludes.

What food is good for bacterias that keep you slim?

Good Food for Bacterias that keep you slim

Junk food kills the gut bacteria that can help keep people thin, while Belgian beer and coffee increase them, a new book by a leading academic claims.


Microbes that live in people's bodies make up 90% of living cells and when disrupted could be a major cause of obesity, according to Tim Spector, a professor of genetic epidemiology at King's College London.

In a new book called The Diet Myth, he researched the links between microbes, food and health in an attempt to an gain insight into the burgeoning obesity crisis.

Meanwhile, a new report by London's Overseas Development Institute (ODI) found prices of fruit and vegetables had risen 30% in the UK since 1980 while those of processed foods, meat and dairy had dropped 25%. Ice cream experienced the biggest price fall.

Prof Spector's research also found sweeteners in diet fizzy drinks had adverse affects on metabolism, leading to weight gain, while fasting diets such as the 5:2 diet could benefit microbes and metabolism.


But he found some elements were down to genetics, with a third of people naturally possessing microbes which prevented them getting fat, while genes even determined some people's preference for salads, broccoli or garlic.

A statement from the publishers Weidenfeld and Nicolson, said: "Compared to our recent ancestors who lived outside cities, with rich and varied diets and without antibiotics, we have only a fraction of the diversity of species of microbes living in our guts. Scientists are only now starting to understand the long-lasting impact this has on all of us.


"Only by understanding what makes our own personal microbes tick and interact with our bodies can we overcome the confusion of modern diets and nutrition to regain the correct balance of our ancestors."


Prof Spector also tweeted: "Burger diet reduces microbe diversity by 40% in a few days."


And on using his son as a research subject for the book, he said: "Feeding junk food to my son's poor gut microbes - a massacre in the name of science."


In its report, entitled The Rising Cost of a Healthy Diet, the ODI analysed data from five countries, including the UK and USA.
The researchers said: 

"Typical UK diets are not balanced in accordance with dietary recommendations, with excessive consumption of grains and other starchy foods, protein-rich foods, oils, fats, and sugar - coupled with particularly low intake of fruit and vegetables."


And they suggested there may be a case for taxation of certain foods, although it would come down to "political appetite".


They said: "In terms of what might be taxed and subsidised, this report suggests that energy-dense foods might be taxed, while fruit and vegetables whose prices often rise compared to other foods, might be subsidised."