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  Over and over studies find that a person's diet is linked to health and diseases, and now a study finds that an unhealthy diet is linked to shrinkage of the brain, specifically the volume of the left hippocampus. The biggest effects on the hippocampus are found with both greater consumption of an unhealthy diet and lower consumption of a healthy diet.  The hippocampus is a brain structure associated with both learning and memory, as well as mood regulation, and is specifically implicated in depression. In dementia and Alzheimer's disease, the hippocampus is one of the first regions of the brain to suffer damage. want to protect your hippocampus from shrinkage. The researchers themselves  suggest that the effects may be reversible, and suggest "dietary interventions to promote hippocampal health". Once again, a healthy diet means lots of plant-based foods (for example, a Mediterranean based diet with lots of fruits, vegetables, legumes, nuts, berries, seeds), and decreasing a Western-style diet with highly processed foods, low fiber, lots of meat, fat,  and refined sugars. From Medscape:

Unhealthy Diet May Shrink the Brain

Consumption of an unhealthy Western diet characterized by meat, hamburgers, chips, and soft drinks, may reduce the volume of the left hippocampus, whereas a healthy diet of fresh vegetables and fish may increase hippocampal volume. In a study of more than 250 individuals, investigators found that during a period of 4 years, there was a difference of more than 200 cubic millimeters in hippocampal volume between individuals who ate a healthy diet and those who consumed an unhealthy diet.

"These findings suggest the potential for dietary interventions to promote hippocampal health, decrease age-related atrophy, and prevent negative health outcomes associated with hippocampal atrophy," they add. Previous studies have shown that quality of diet is associated with depression and cognitive health. Animal research indicates that this may be mediated by changes in the hippocampus. Specifically, a high-fat diet reduces brain-derived neurotrophic factor levels, which impairs neuronal plasticity, learning, and behavior.

For the current study, the researchers examined data from the Personality and Total Health Through Life Study on 255 individuals aged 60 to 64 years at baseline....Participants were classified as consuming either a "prudent/healthy diet," consisting of fresh vegetables, salad, fruit, and grilled fish, or a "Western/unhealthy diet," consisting of roast meat, sausages, hamburgers, steak, chips, crisps, and soft drinks. A 1-point difference on an 11-point scale of consumption of each type of diet corresponded to 1 standard deviation difference....

The investigators found that for each standard deviation increase in consumption of the "prudent diet," there was a 45.7 cubic millimeter increase in left hippocampal volume. In contrast, each standard deviation increase in consumption of the Western diet was independently associated with a 52.6 cubic millimeter decrease in the volume of the left hippocampusThe impact of diet on hippocampal volume was independent of age, sex, education, labor-force status, depressive symptoms, use of medication, physical activity, smoking, hypertension, and diabetes.


The difference in left hippocampal volume between those with a healthy diet and those with an unhealthy diet was 203 cubic millimeters, which accounted for 62% of the average decline in left hippocampal volume during the 4-year study period. Interestingly, there were no significant associations between right hippocampal volume and dietary patterns, although there was a nonsignificant relationship.

In an interview with Medscape Medical News, Dr Jacka pointed out the the research was observational in nature, and therefore it cannot be stated for certain that the Western diet is causing the hippocampus to shrink. "However, there have been many studies in animals that show that a diet high in saturated fats and refined sugars has a very potent negative impact on the brain proteins (neurotrophins) that both protect neurons from oxidative stress and promote the growth of new neurons in the hippocampus," she said.

"Similarly, there are many studies that show that food components high in antioxidants or protective lipids, such as omega-3 fatty acids, increase levels of these proteins. There are also many studies showing that the animal equivalent of 'junk food' diets impair hippocampal-dependent learning and memory." Crucially, Dr Jacka believes that switching from a Western to a "prudent" diet would lead to increases in hippocampal volume."From what we know so far, it seems that neurotrophin levels and hippocampal volume and function are relatively labile and readily influenced by environmental exposures, including both diet and physical activity," she said. "So there is every reason to believe that the noxious impact of unhealthy diets can be reversed by dietary improvement and vice versa."

This is of particular importance given that the latest Global Burden of Diseases data from The Lancet indicate that unhealthy diets are the leading cause of early mortality worldwide and that mental disorders are the leading cause of global disability. With a growing body of evidence showing that unhealthy diets are linked to mental, neurodegenerative, and neurodevelopmental disorders, Dr Jacka said the findings have "enormous implications for public health."

"It's the first time that a dietary pattern has been linked to specific changes in the brain. We've known for a long time that there's a correlation between dietary pattern and the risk of a number of brain illnesses, like depression and dementia, and the mechanism behind this, we believe, involves neuroplastic processes of how food affects brain growth. This is the first study that's really shown that quite conclusively," he said.    BMC Med. Published online September 8, 2015. Full text

 The blue structure in the brain is the hippocampus. Credit: BrainHQ

Two studies that talk about a healthy diet and health benefits.From Science Daily:

Home cooking a main ingredient in healthier diet, study shows

People who frequently cook meals at home eat healthier and consume fewer calories than those who cook less, according to new Johns Hopkins Bloomberg School of Public Health research."When people cook most of their meals at home, they consume fewer carbohydrates, less sugar and less fat than those who cook less or not at all -- even if they are not trying to lose weight," says Julia A. Wolfson, MPP, a CLF-Lerner Fellow at the Johns Hopkins Center for a Livable Future and lead author of the study.The findings also suggest that those who frequently cooked at home -- six-to-seven nights a week -- also consumed fewer calories on the occasions when they ate out.

Wolfson and co-author Sara N. Bleich, PhD, an associate professor in the Department of Health Policy and Management at the Bloomberg School, analyzed data from the 2007-2010 National Health and Nutrition Examination Survey from more than 9,000 participants aged 20 and older... The researchers found that 8 percent of adults cooked dinner once or less a week and this group consumed, on an average day, 2,301 total calories, 84 grams of fat and 135 grams of sugar. Forty-eight percent of participants cooked dinner six to seven times a week and they consumed 2,164 calories, 81 grams of fat and 119 grams of sugar on an average day.

The research found blacks are more likely to live in households where cooking occurs less frequently than whites; and individuals who work more than 35 hours a week outside the home also cook less often.

From Medical Xpress:

Healthy diets are good for the kidneys

A healthy diet may help protect the kidneys, according to two studies that will be presented at ASN Kidney Week 2014 November 11¬-16 at the Pennsylvania Convention Center in Philadelphia, PA. Dietary modifications may be a low-cost, simple intervention to reduce the burden of chronic kidney disease (CKD). 

A higher-quality diet, as measured using 3 different scoring systems for dietary qualities known to reduce the risk of cardiovascular disease, was associated with a 16% to 23% reduced risk of needing dialysis or dying from kidney problems. Higher-quality diets included those high in fruits, vegetables, and unsaturated fats. The researchers also found that high sodium intake (average of 4.7g g/day) was linked with an increased risk of needing dialysis or dying from kidney problems, but no benefit was seen for low sodium intake (average 2.0 g/day) compared with moderate intake. In contrast, high potassium intake was associated with a reduced future risk.

From Science Daily:

Healthy lifestyle may cut stroke risk in half for women

Women with a healthy diet and lifestyle may be less likely to have a stroke by more than half, according to a study. The study looked at five factors that make up a healthy lifestyle: healthy diet; moderate alcohol consumption; never smoking; physically active; and healthy body mass index (BMI). Compared with women with none of the five healthy factors, women with all five factors had a 54-percent lower risk of stroke.

For the study, 31,696 Swedish women with an average age of about 60 completed a 350-item questionnaire about their diet and lifestyle. They were then followed for an average of 10 years. A healthy diet was defined as within the top 50 percent of a recommended food score measuring how often the participants ate healthy foods such as fruits, vegetables and low-fat dairy products. Moderate alcohol consumption was defined as three to nine drinks per week. Physically active was defined as walking or biking at least 40 minutes a day along with more vigorous exercise at least one hour per week. Healthy BMI was considered below 25.

Most of the women had two or three of the healthy factors. Only 589 women had all five healthy factors, and 1,535 had none. There were 1,554 strokes among study participants. The risk of stroke steadily decreased with each additional healthy lifestyle factor.

Women who had a healthier diet were 13 percent less likely to have a type of stroke called a cerebral infarction than those whose diet was not as healthy. Women with healthier diets had a rate of 28 strokes per 10,000 women per year compared to 43 strokes per 10,000 women per year among those with a less healthy diet.

Cerebral infarction is the most common cause of stroke, accounting for up to 80 to 85 percent of all strokes. Cerebral infarction is caused by a blockage in a blood vessel preventing blood and oxygen from getting to an area of the brain.

There was no relationship between the healthy factors and the risk of hemorrhagic stroke. Hemorrhagic stroke, which is caused by bleeding in and around the brain, accounts for about 15 to 20 percent of all strokes.

What if a doctor said you could avoid years of taking medication (and all their side effects and cost), better heart health, and avoid a heart attack by adopting some lifestyle changes. Could you do it? Would you? How to avoid 4 out 5 heart attacks, from Medical Xpress:

Healthy lifestyle choices may dramatically reduce risk of heart attack in men

Following a healthy lifestyle, including maintaining a healthy weight and diet, exercise, not smoking and moderating alcohol intake, could prevent four out of five coronary events in men, according to a new study publishing today in the Journal of the American College of Cardiology.

While mortality from heart disease has declined in recent decades, with much of the reduction attributed to medical therapies, the authors said prevention through a healthy lifestyle avoids potential side effects of medication and is more cost effective for population-wide reductions in coronary heart disease. 

For the study, researchers examined a population of 20,721 healthy Swedish men aged 45-79 years of age and followed them for 11 years. Lifestyle choices were assessed through a questionnaire exploring diet, alcohol consumption, smoking status, level of physical activity and abdominal adiposity (belly fat). Men in the study with the lowest risk were non-smokers, walked or cycled for at least 40 minutes per day, exercised at least one hour per week, had a waist circumference below 95 centimeters, consumed moderate amounts of alcohol, and followed a healthy diet with a regular consumption of fruits, vegetables, legumes, nuts, reduced-fat dairy products, whole grains and fish.

The researchers found a clear reduction in risk for heart attack for each individual lifestyle factor the participants practiced. For instance having a low-risk diet together with a moderate alcohol consumption led to an estimated 35 percent lower risk of heart attack compared to the high-risk group, those who practice none of the low-risk factors.

Men who combined the low-risk diet and moderate alcohol consumption with not smoking, being physically active and having a low amount of abdominal fat, had 86 percent lower risk. Researchers found similar results in men with hypertension and high cholesterol levels.

The burden of cardiovascular disease could be significantly reduced through programs targeted to men and promoting low-risk lifestyle choices. Even in those who take medication, an additional reduction in risk for chronic heart disease has been observed in those with a healthy lifestyle.

From John M., a cardiac electrophysiologist, who expressed his frustration with unnecessary heart disease, and commented on this study on

Let’s stop the unnecessary treatment of heart disease

There are many reasons doctors suffer from burnout and compassion fatigue. One of the least-mentioned of these reasons is that much of what we do is so damn unnecessary. In the US, the land of excess everything, caregivers, especially cardiologists, spend most of our time treating human beings that didn’t need to have disease.

Let’s be clear and honest: Lifestyle-related disease is largely unnecessary.

These days, there is so much unnecessary disease that caregivers, especially cardiologists, rarely see it. We look past the obesity right to the cholesterol number and ECG. And then we pull out the prescription pad for the guideline-directed pills. Just typing that causes me angst.

Another study showing the benefits of eating berries. From the January 23, 2014 Science Daily:

Lingonberries halt effects of high-fat diet

Lingonberries almost completely prevented weight gain in mice fed a high-fat diet, a study at Lund University in Sweden has found -- whereas the 'super berry' açai led to increased weight gain. The Scandinavian berries also produced lower blood sugar levels and cholesterol.

Some of the mice were fed a low-fat diet, while the majority of the animals were fed a diet high in fat. They were then divided into groups, where all except a control group were fed a type of berry -- lingonberry, bilberry, raspberry, crowberry, blackberry, prune, blackcurrant or açai berry.

When the mice were compared after three months, it could be observed that the lingonberry group had by far the best results. The mice that had eaten lingonberries had not put on more weight than the mice that had eaten a low-fat diet -- and their blood sugar and insulin readings were similar to those of the 'low-fat' mice. Their cholesterol levels and levels of fat in the liver were also lower than those of the animals who received a high-fat diet without any berries.

Blackcurrants and bilberries also produced good effects, although not as pronounced as the lingonberries. The açai berries, on the other hand, came last, although they had actually been included in the study for the opposite reason -- the researchers wanted to see how well the Nordic berries would do in comparison with the Brazilian 'super berry'.

The good results from lingonberries may be due to their polyphenol content, according to the researchers. They will now continue to work on understanding the molecular mechanisms involved in the effect of the lingonberries. They will also see whether the effect can be observed in humans.