I grew up eating a lot of yogurt and fish. I wonder how my brain would have developed without those foods. They have been shown to improve intelligence,[1] fight depression,[2] and reduce the risk of cognitive problems.[3] My mom got fresh fish every morning from the fishermen’s boats still on the beach. Mercury in fish was not a problem back then. Neither was yogurt. My father made it himself from raw organic milk, without sugar, colorings, or preservatives.
Now that I am over the hill, I wonder about my brain aging. If you do, too, I hope you find this Brain Issue helpful.
Hugo Rodier, MD
Environment people are raised in may be as important as genes in determining risk for depression
Reuters (12/21, Weinstock) reports, “In a large retrospective study, researchers looked at depression among more than 2.2 million people in Sweden and their parents.” Investigators then “found that genetic factors and household environment contributed equally to odds that the illness would be ‘transmitted’ from parents to offspring.” The findings were published online Dec. 13 in JAMA Psychiatry. Reuters adds, “In 2015, almost 7 percent of all adults in the US, or an estimated 16.1 million individuals age 18 or older, reported having had at least one major depressive episode in the past year,” figures from the National Institute of Mental Health reveal.
Mediterranean Diet Improves Depression
Medscape – Dec 22, 2017. Diet matters when it comes to mental health. When people with severe depression followed the Mediterranean diet, they experienced a significant reduction in symptom severity that lasted up to 6 months. In one of the first randomized controlled trials to examine the effect of the Mediterranean diet supplemented with fish oil in people with severe depression, researchers found the diet to be associated with a reduction in depression symptoms. “While both the intervention and control groups experienced significant mental health improvements, participants eating the Mediterranean diet experienced a greater reduction (45%) in the severity of their depression compared with the control group (27%),” study investigator Natalie Parletta, PhD, told Medscape Medical News. Dr Parletta is a senior research fellow from the Center for Population Health Research, University South Australia, in Adelaide. The study was published online December 18 in Nutritional Neuroscience.
Population research has shown a link between diet and depression. The current study, the authors note, is only the second randomized controlled trial to use a Mediterranean dietary intervention in people with severe depression. The first trial, published earlier this year in BMC Medicine, was also conducted in patients with moderate to severe depression. In that study, following the Mediterranean diet was found to be associated with significant improvements in depression scores. However, in contrast to the latest study, it ended at 3 months, used buddies for the social control group, and did not supplement the diet with fish oil.
To further investigate the impact of the Mediterranean diet on mental health and quality of life in people with severe depression, the researchers recruited 152 adults aged 18 to 65 years (105 women and 47 men). Thirty-eight percent of participants reported a diagnosis of depression, and 36% reported taking an antidepressant.
Participants were randomly assigned to receive a traditional Mediterranean diet (n = 75) or a traditional Mediterranean diet supplemented with fish oil or a control intervention (n = 77)
The Mediterranean diet intervention included an initial nutritional consultation, biweekly group cooking workshops, easy, inexpensive recipes, and take-home food hampers for making the recipes. The control intervention involved biweekly meetings that included social activities such as board games, book clubs, and photo sharing. Participants were provided with light snacks, such as biscuits, dips, cheese, crackers, coffee, tea, juice, or water.
Participants were assessed at baseline, 3 months, and 6 months using validated, reliable instruments. Primary mental health outcomes were assessed with the Depression, Anxiety and Stress Scale and the Assessment of Quality of Life.
Chronic gum inflammation may be associated with higher risk of Alzheimer’s disease, research suggests
Reuters (8/17, Boggs) reports that research suggests “chronic gum inflammation” may be linked to “an increased risk of developing Alzheimer’s disease.” Investigators “found no overall link between periodontitis and Alzheimer’s, but people who had” periodontitis “for 10 or more years were 70 percent more likely than people without periodontitis to develop Alzheimer’s disease.” The findings were published in Alzheimer’s Research and Therapy.
Lithium in drinking water may impact Alzheimer’s risk
Reuters (8/23, Emery) reports, “Long-term consumption of tiny amounts of lithium may reduce the risk of Alzheimer’s disease and other forms of dementia, but only if the dose isn’t too small,” researchers found after comparing “the estimated amount found in the water supplies of 275 municipalities” in Denmark “to the rates of dementia, including Alzheimer’s, in those areas.” The study also revealed that “the wrong amount may actually increase dementia risk.” The findings were published online Aug. 23 in JAMA Psychiatry.
Medscape (8/23, Brooks) reports the study “included 73,731 patients with dementia and 733,653 controls.” The study found that “the incidence rate ratio (IRR) of dementia was lower in individuals exposed to 10.1 µg/L of lithium or more compared with their peers exposed to 2.0 to 5.0 µg/L, reaching statistical significance among those exposed to greater than 15.0 µg/L of lithium (P < .001).” But, “exposure to 5.1 to 10.0 µg/L of lithium was associated with an increased IRR of dementia compared with 2.0 to 5.0 µg/L (P < .001).”
People with risk factors for heart attacks, stroke may be more likely to develop dementia
Reuters (8/7, Rapaport) reports, “Middle-aged people with risk factors for heart attacks and stroke may be more likely to develop dementia in old age than people with healthy cardiovascular systems,” researchers concluded. The study revealed that smoking, diabetes, hypertension, and prehypertension were associated with “higher odds of dementia.”
HealthDay (8/7, Thompson) reports that “investigators tracked nearly 15,800 participants in the Atherosclerosis Risk in Communities (ARIC) study,” which is “a US National Institutes of Health-funded project designed to track the effect of hardened arteries on people’s long-term health.” All participants were followed for about 25 years. The findings were published online Aug. 7 in JAMA Neurology.
Blood pressure fluctuations linked to dementia
Reuters (8/7, Rapaport) reports a study of 1,674 older adults published in Circulation found that “people with the most variations in blood pressure,” which was measured through a month of home blood pressure readings, “were more than twice as likely to develop dementia” within the next five years. While the study didn’t address causation, lead study author Tomoyuki Ohara, MD, of the Graduate School of Medical Sciences at Kyushu University in Fukuoka City, said, in Reuters’ words, “it’s possible that daily variation in blood pressure might cause changes in the brain’s structure and function that contribute to the development of dementia.” Costantino Iadecola, MD, director of the Feil Family Brain and Mind Research Institute at Weill Cornell Medicine in New York wrote in an accompanying editorial that, in Reuters’ words, “fluctuations in blood pressure could be a symptom of cognitive decline in progress rather than a risk factor for developing dementia in the future.”
HealthDay (8/7, Reinberg) reports that those whose systolic blood pressure “fluctuated from day-to-day were more than twice as likely to develop any type of dementia or Alzheimer’s disease compared to those with more stable day-to-day blood pressure,” as well as “nearly three times more likely to develop vascular dementia, caused by hardening of the arteries.” Dr. Ohara said, “Further studies are needed to clarify whether day-to-day blood pressure variation is an indicator of future dementia or a medical target for the prevention of dementia.”
Daily serving of leafy greens may help slow age-related decline in memory, thinking skills
In “Science Now,” the Los Angeles Times (12/20, Healy) reports that “older people who ate at least one serving of leafy greens a day had a slower rate of decline on tests of memory and thinking skills than did people who rarely or never ate these vegetables,” researchers concluded. The study revealed that “after almost five years, regular consumers of such veggies as kale, spinach, collard greens and lettuce enjoyed a mental edge that was the equivalent of 11 years in age.” The findings were published online Dec. 20 in Neurology.
Research on loneliness and social isolation indicates it can lead to cognitive impairment
The New York Times (12/11, Brody, Subscription Publication) reports on research into the “potentially harmful effects of loneliness and social isolation on health and longevity,” including work regarding “who is likely to be most seriously affected, and what kinds of interventions may reduce the associated risks.” Julianne Holt-Lunstad and Timothy B. Smith, both at Brigham Young University, explained that “loneliness and social isolation don’t necessarily go hand-in-hand,” because, “isolation denotes few social connections or interactions, whereas loneliness involves the subjective perception of isolation.” Holt-Lunstad has found that “loneliness peaks in adolescents and young adults, then again in the oldest old.” Loneliness has also been suggested as “a preclinical sign for Alzheimer’s disease.” The Times cites several studies finding that loneliness, but to a much greater degree depression, appears to lead to cognitive impairment.
Vigorous exercise may delay progression of Parkinsonism
The Chicago Tribune (12/11, Olumhense) reports researchers found that “vigorous exercise is a safe way to potentially delay the progression of Parkinson’s disease.” The findings were published in JAMA Neurology. Codrin Lungu, MD, a program director at the National Institute of Neurological Disorders and Stroke, said, “Several lines of evidence point to a beneficial effect of exercise in Parkinson’s disease.”
HealthDay (12/11, Preidt) reports Daniel Corcos, one of the study’s co-authors at Northwestern University’s Feinberg School of Medicine, said that the findings challenge the idea that exercise is too stressful for people with Parkinson’s disease.
- Determinants of fluid intelligence in healthy aging: Omega-3 polyunsaturated fatty acid status and frontoparietal cortex structure, J. Nutritional Neuroscience Published online: 11 May 2017
Gut Bacteria May Influence Infant Intelligence – Medscape – Dec 21, 2017 ↑ - Lipid correlates of antidepressant response to omega-3 polyunsaturated fatty acid supplementation: A pilot study, J. Prostaglandins, Leukotrienes and Essential Fatty Acids 2017;119:38 ↑
- N-3 Fatty acids, Mediterranean diet and cognitive function in normal aging: A systematic review, J. Experimental Gerontology 2017;91:39↑