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Published on 1 Comment on Some More Benefits of Eating Chocolate

Image result for dark chocolate Great news for chocolate lovers! A review of 19 good studies (studies with people randomly assigned to different conditions) found that chocolate (whether from cocoa products, chocolate, or cocoa beverages), overall had beneficial effects on cardiometabolic health, and that it may improve lipid metabolism, and reduce inflammation and insulin resistance. This held for both men and women. The main assumption is that it is the flavanols in chocolate that has the beneficial effects on health.

From Medical Xpress: Cocoa compound linked to some cardiovascular biomarker improvements

To the tantalizing delight of chocolate lovers everywhere, a number of recent studies employing various methods have suggested that compounds in cocoa called flavanols could benefit cardiovascular health. Now a systematic review and meta-analysis of 19 randomized controlled trials (RCTs) of cocoa consumption reveals some further pieces of supporting evidence..... "We found that cocoa flavanol intake may reduce dyslipidemia (elevated triglycerides), insulin resistance and systemic inflammation, which are all major subclinical risk factors for cardiometabolic diseases."

Liu noted some limitations in the trials. All studies were small and of short duration, not all of the biomarkers tracked in these studies changed for the better, and none of the studies were designed to test directly whether cocoa flavanol consumption leads to reduced cases of heart attacks or type 2 diabetes. But taking into account some of these heterogeneities across studies, the team's meta-analysis summarizing data from 19 trials found potential beneficial effects of flavanol-rich cocoa on cardiometabolic health. There were small-to-modest but statistically significant improvements among those who ate flavanol-rich cocoa product vs. those who did not.

The greatest effects were seen among trial volunteers who ate between 200 and 600 milligrams of flavanols a day (based on their cocoa consumption). They saw significant declines in blood glucose and insulin, as well as another indicator of insulin resistance called HOMA-IR. They also saw an increase in HDL, or "good," cholesterol. Those consuming higher doses saw some of the insulin resistance benefits and a drop in triglycerides, but not a significant increase in HDL. Those with lower doses of flavanols only saw a significant HDL benefit. 

In general, Lin said, where there were benefits they were evident for both women and men and didn't depend on what physical form the flavanol-rich cocoa product was consumed in —dark chocolate vs. a beverage, for example.

Published on Leave a comment on Mediterranean Diet and Caffeine Linked to Lower Risk of Macular Degeneration

One of the dreaded afflictions of getting older is age-related macular degeneration (AMD), which is a leading cause of vision loss in Americans 60 years and older. It has no cure. Thus this study finding that eating a Mediterranean diet, and especially lots of fruit, was associated with a lower risk of macular degeneration was welcome news. They also found a protective effect from drinking caffeinated beverages - about 78 mg of caffeine per day (about one cup of coffee or one shot of espresso). A Mediterranean diet stresses eating fruits, vegetables, nuts, whole grains, legumes, fish, seeds, and olive oil. From Science Daily:

Fruit-rich Mediterranean diet with antioxidants may cut age-related macular degeneration risk by more than a third

People who closely follow the Mediterranean diet -- especially by eating fruit -- may be more than a third less likely to develop age-related macular degeneration, a leading cause of blindness, according to a study presented at AAO 2016, the 120th annual meeting of the American Academy of Ophthalmology. The study is the first to identify that caffeine may be especially protective against AMD.

Many studies have confirmed the health benefits of the Mediterranean diet, which emphasizes eating fruits, vegetables, whole grains, legumes, nuts, healthy fats and fish, and limiting red meat and butter. The diet has been shown to improve heart health and reduced risk of cancer, but there has been little research on whether its benefits can extend to eye disease. To determine this, researchers studied a Portuguese population to see whether adherence to the diet impacted people's risk of AMD. Their findings revealed a significant reduction in risk in those who ate a Mediterranean diet most frequently, and particularly among those who consumed more fruit and caffeine.

Researchers at the University of Coimbra in Portugal studied 883 people age 55 or older in the central region of the country between 2013 and 2015. Of those, 449 had AMD in its early stages before vision loss, and 434 did not have AMD. Researchers assessed their diets based on a questionnaire asking how often they ate foods associated with the Mediterranean diet. The more they ate foods associated with the diet, the higher the score, from 0-9. Those who closely followed the diet scored a 6 or greater. Their findings were as follows:

Higher diet adherence scores meant lower AMD risk Of those who did not closely follow the diet (scored below a 6), 50 percent had AMD. Of those who did closely follow the diet (scored 6 or above), only 39 percent had AMD. This represents a 35 percent lower risk compared to those who did not adhere to the diet.

Fruits were especially beneficial Researchers analyzed consumption of foods and found that people who consumed higher levels of fruit were significantly less likely to have AMD. Of those who consumed 150 grams (about five ounces) or more of fruit a day: 54.5 percent did not have AMD and 45.5 percent had AMD. Overall, people who ate that much fruit or more each day were almost 15 percent less likely to have AMD, based on an odds ratio calculation.

Caffeine and antioxidants also were protective Researchers used a computer program to analyze the participants' consumption of micronutrients, according to their answers on the questionnaire. They found higher consumption of antioxidants such as caffeine, beta-carotene and vitamins C and E was protective against AMD. Of those who consumed high levels of caffeine (about 78 mg a day, or the equivalent of one shot of espresso): 54.4 percent did not have AMD and 45.1 percent had AMD....The researchers opted to look at caffeine because it is a powerful antioxidant that is known to be protective against other conditions, such as Alzheimer's disease.

Published on Leave a comment on Eat Calcium Rich Foods, Not A Supplement

Image result for calcium rich foods, wikipedia Once again, research shows that a supplement is not beneficial and may have some health harms, while eating foods rich in the mineral or vitamin being measured has health benefits. A ten year study found that calcium supplements are not beneficial and linked to health harm - they raised the risk of atherosclerosis, as measured by "coronary artery calcification" or plaque buildup in arteries, while a diet high in calcium rich foods was linked with health benefits (a protective effect). Other studies have found a higher risk for other health problems with calcium supplements (heart attacks, kidney stones, death),

Currently an estimated 43 percent of American adults take a supplement that includes calcium. Instead, for health benefits, focus on eating calcium rich foods. Some calcium rich foods are: dairy products (milk, cheese, yogurt, kefir), sardines, salmon, broccoli, collard greens, kale, edamame, figs, oranges, white beans, okra, tofu, and almonds. From Science Daily:

Calcium supplements may damage the heart

After analyzing 10 years of medical tests on more than 2,700 people in a federally funded heart disease study, researchers at Johns Hopkins Medicine and elsewhere conclude that taking calcium in the form of supplements may raise the risk of plaque buildup in arteries and heart damage, although a diet high in calcium-rich foods appears be protective.

In a report on the research....the researchers caution that their work only documents an association between calcium supplements and atherosclerosis, and does not prove cause and effect. But they say the results add to growing scientific concerns about the potential harms of supplements....But our study adds to the body of evidence that excess calcium in the form of supplements may harm the heart and vascular system.

"The researchers were motivated to look at the effects of calcium on the heart and vascular system because studies already showed that "ingested calcium supplements -- particularly in older people -- don't make it to the skeleton or get completely excreted in the urine, so they must be accumulating in the body's soft tissues," says nutritionist John Anderson, Ph.D., professor emeritus of nutrition at the University of North Carolina at Chapel Hill's Gillings School of Global Public Health and a co-author of the report. Scientists also knew that as a person ages, calcium-based plaque builds up in the body's main blood vessel, the aorta and other arteries, impeding blood flow and increasing the risk of heart attack.

Their study focused on 2,742 of these participants who completed dietary questionnaires and two CT scans spanning 10 years apart. The participants chosen for this study ranged in age from 45 to 84, and 51 percent were female. Forty-one percent were white, 26 percent were African-American, 22 percent were Hispanic and 12 percent were Chinese. At the study's onset in 2000, all participants answered a 120-part questionnaire about their dietary habits to determine how much calcium they took in by eating dairy products; leafy greens; calcium-enriched foods, like cereals; and other calcium-rich foods....The coronary artery calcium tests were repeated 10 years later to assess newly developing or worsening coronary heart disease.

Next, the investigators focused on the differences among those taking in only dietary calcium and those using calcium supplements. Forty-six percent of their study population used calcium supplements. The researchers.....found that supplement users showed a 22 percent increased likelihood of having their coronary artery calcium scores rise higher than zero over the decade, indicating development of heart disease....Among participants with highest dietary intake of calcium -- over 1,022 milligrams per day -- there was no increase in relative risk of developing heart disease over the 10-year study period.

Excerpts from the original study (Please note:  CVD = cardiovascular disease, CAC = coronary artery calcification) in the  Journal of the American Heart Association:  Calcium Intake From Diet and Supplements and the Risk of Coronary Artery Calcification and its Progression Among Older Adults: 10‐Year Follow‐up of the Multi‐Ethnic Study of Atherosclerosis (MESA)

Recent evidence derived from randomized, controlled trials, including the Women's Health Initiative, have raised a concern for an association between calcium supplement use and increased risk for CVD events.12, 13, 14 Among calcium supplement users, a high intake of calcium greater than 1400 mg/day has been reported to be associated with higher death rates from all causes, including from CVD.15

The purported CVD risk associated with total calcium intake may depend on the source of calcium intake.3 Intake of calcium from food sources has not been shown to increase CVD risk, whereas a signal for increased risk of myocardial infarction (MI) among calcium supplement users has been reported.7 In a similar fashion, dietary calcium intake may decrease risk of kidney stones, whereas calcium supplementation may increase risk.16 One explanation for this apparent paradox may be that large boluses of calcium intake through supplements may transiently elevate serum calcium concentrations,17, 18 which, in turn, may lead to vascular calcification and other adverse health effects.

In summary, results from this long‐term study of 10 years showed a protective relationship between total calcium intake and incident coronary atherosclerosis, particularly among nonsupplement users. Even though mean total calcium intake in quintile 5 was greater than the upper limits of current recommendations, no increased risk of CAC progression was found, and the highest quintile of calcium intake actually had decreased risk of incident CAC among those without prevalent CAC at baseline. However, we found evidence that calcium supplement use was independently associated with incident CAC, whether or not we adjusted for total calcium intake.

Published on Leave a comment on Endocrine Disruptors In Fast Food

Recent research examined levels of endocrine disruptors called phthalates in people eating fast food. Researchers found evidence of a dose–response relationship between fast food intake and exposure to phthalates - the more one eats fast food, the more phthalates (actually metabolites of the phthalates) can be measured in the person's urine. Fast food consumers had higher urinary levels of the phthalates DEHP, DiNP, and BPA than those not consuming fast food (even though the differences in levels of BPA among groups were "non-significant"). This is of concern because these endocrine disruptors are linked to a number of health problems. (Earlier discussion of this research.)

DEHP, DiNP, and BPA are detected in over 90% of the population in the US, but since there are many health concerns - it is better to have lower levels than higher levels. (Zero levels would be best). Note that phthalates and BPA are quickly metabolized and excreted in urine, with elimination half-lives of less than 24 hr - which is why the study looked at what had been eaten in the last 24 hours. But this also shows that one can quickly reduce their levels in the body.

Some possible sources of phthalate contamination in fast food are: PVC tubing, vinyl gloves used for food handling, and food packaging, including beverage cans - the chemicals leach or migrate out into the food and then are ingested. (More on chemicals migrating from containers to food), Fast food was defined as food obtained from restaurants without waiter service and from pizza restaurants, as well as all carry-out and delivery food. Another excellent reason to cut back on fast food (like we don't have enough reasons already!). The following news report discusses the research. From Environmental Health Perspectives:

Phthalates in Fast Food: A Potential Dietary Source of Exposure

Many research studies have surveyed nutritional habits, but fewer have studied how food processing and packaging might introduce unwanted chemicals into foods. In this issue of EHP, researchers report that fast food consumption appears to be one source of exposure to the chemicals di(2-ethylhexyl) phthalate (DEHP) and diisononyl phthalate (DiNP).1

The authors used data from the National Health and Nutrition Examination Survey (NHANES) to estimate the percentage of individuals’ calories that came from fast food, fat intake attributable to fast food consumption, and fast food intake by food group. During NHANES interviews, respondents had reported their diet from the preceding 24 hours. Fast food was defined as food obtained from restaurants without waiter service and from pizza restaurants, as well as all carryout and delivery food.2 ....The final study population included nearly 9,000 people aged 6 years or older. Approximately one-third of people surveyed had eaten fast food in the preceding 24 hours. Study participants who ate fast food were more likely to be male, under age 40, and non-Hispanic black, and to have higher total calorie and total fat intake from fast food, compared with the general population.1

Fast food consumers had higher urinary levels of DEHP, DiNP, and BPA than non-consumers, although the differences in average urinary levels were small and for BPA were non-significant. When fast food intake was categorized by food group, DEHP metabolites were associated with intake of grains and “other” (a category that included vegetables, condiments, potato items, beverages, and more). DiNP metabolites were associated with intake of meat and grains.1

The authors also found that the associations between phthalates and fast food were not uniform across the population.1They speculate that the pronounced association they saw between fast food consumption and DEHP in black consumers could reflect higher overall consumption of fast food and/or different food choices among this population. Prior research suggests that predominately black neighborhoods in urban areas have a greater density of fast food restaurants than white neighborhoods.3

The authors point to PVC tubing, vinyl gloves used for food handling, and food packaging as possible sources of phthalate contamination in fast food. DEHP is a ubiquitous high-molecular-weight phthalate that has been removed from some products due to concerns about potential adverse health effects.5 In some cases it is being replaced with DiNP.2

The related Environmental Health Perspectives research article:  Recent Fast Food Consumption and Bisphenol A and Phthalates Exposures among the U.S. Population in NHANES, 2003–2010

Experimental animal studies demonstrate that DEHP and DiNP have endocrine-disrupting properties because of their anti-androgenic effects on the male reproductive system (National Research Council 2008). Human exposure to DEHP has been associated with adverse reproductive, neurobehavioral, and respiratory outcomes in children (Braun et al. 2013; Ejaredar et al. 2015) and metabolic disease risk factors such as insulin resistance in adolescents and adults (James-Todd et al. 2012; Attina and Trasande 2015). Though epidemiologic evidence of DiNP is less complete, recent studies report associations between exposure and similar health outcomes including adverse respiratory and metabolic outcomes in children (Bertelsen et al. 2013; Attina and Trasande 2015). BPA is also a suspected endocrine disrupter, and experimental and human evidence suggest that BPA is a reproductive toxicant (Peretz et al. 2014). In addition, prenatal BPA exposure has also been associated with adverse neurobehavioral outcomes in children (Mustieles et al. 2015).

Given the concern over chemical toxicity, it is important to identify modifiable sources of exposure that may be targeted for exposure reduction strategies. Simulated exposure modeling, observational epidemiologic studies, and intervention studies all suggest that diet is an important exposure pathway for both high-molecular-weight phthalates and BPA.....Phthalates have been shown to leach into food from PVC in materials like tubing used in the milking process, lid gaskets, food preparation gloves, conveyor belts and food packaging materials (Cao 2010;Serrano et al. 2014). In fact, an intervention study reported that urinary BPA and DEHP were reduced by 66% and 53–56%, respectively, when participants’ diets were restricted to food with limited packaging (Rudel et al. 2011). Foods high in fat, such as dairy and meat, may be more contaminated by high-molecular-weight phthalates that are more lipophilic such as DEHP (Serrano et al. 2014). Fast food may be an important source of exposure to phthalates and BPA because it is highly processed, packaged, and handled.

Published on Leave a comment on Read Food Labels To Find Hidden MSG

Monosodium glutamate is an additive used as a "flavor enhancer" that has long been used in foods (processed and packaged foods, as well as fast food and restaurant meals) - and it has also been controversial for decades. Even four decades ago some people complained of headaches after having foods with added monosodium glutamate, and since then health complaints have just increased. Since so much is still unknown about the health effects of additives commonly added to foods, then many people just want to avoid them. But it's tricky because manufacturers sneak monosodium glutamate into foods using various other name such as hydrolyzed vegetable protein, autolyzed yeast, glutamic acid, and yeast extract.

The FDA points out on its web-site that monosodium glutamate (MSG) is the "sodium salt of the common amino acid glutamic acid" - in other words, it is a form of glutamic acid. Glutamic acid is an amino acid naturally present in our bodies, and found naturally in many foods, such as tomatoes, cheeses, meat, seaweed, and mushrooms. The FDA views MSG as "generally recognized as safe". But even if a form of something may occur naturally in foods, that does NOT mean that we want to eat foods with added forms of it, or that we should be eating food with added additives, including MSG.

Sometimes the term "natural flavor" is used by the food industry for glutamic acid (which is chemically similar to MSG). So read ingredient lists carefully. And note that "natural flavor" can mean many things, that they are produced in a lab, and that the Food and Drug Administration (FDA) does not require disclosure of components and amounts of "natural flavor". From Tech Insider:

Here’s how food companies sneak MSG into foods

That savory, meaty, salty taste you get after taking a bite of Chinese beef and broccoli or after a crunch into a Doritos nacho cheese chip is unmistakable. It hits your tongue, makes it water, and leaves you craving more. MSG, which stands for monosodium glutamate — a naturally-occurring food additive — is largely responsible for that irresistible taste. Chemists have been infusing it into everything from broths, frozen pizzas, flavored potato chips, salad dressings, deli meats, and hot dogs, for more than a century to make them taste addictively delicious.

MSG is a naturally occurring amino acid that makes up proteins in our bodies. But the compound's safety has been debated for years. While it is generally recognized as safe by the Food and Drug Administration, some claim that it can cause adverse reactions in sensitive people, including chest pain, flushing, and sweating. It's also reportedly caused numbness or burning near the mouth and facial pressure or swelling. While there haven't been any studies to back up this claim, it would be helpful for sensitive or MSG-wary people to know which processed foods contain the ingredient. But because the additive can go by many different names, it can be difficult to tell which foods contain it.

Take this Doritos label, for instance. You can easily tell that there's MSG in it, because it's listed simply by its full name, "Monosodium Glutamate."....But check out this nutrition label for Nissin Chicken Garden Vegetable Flavor Soup. While it does reveal that it indeed contains monosodium glutamate, it also contains many other forms of glutamates that are often considered slight variations on MSG. Hydrolyzed protein, for example, is just proteins that are broken down into their animo acid components – one of which is glutamic acid, another name for MSG. Autolyzed yeast is a similar example, yeast cells are allowed to die and pop open, which releases their innards, which then break down into individual amino acids — including glutamic acid.

MSG can go by these and many other synonymous names as well, including monosodium salt, monohydrate, monosodium glutamate, monosodium glutamate monohydrate, monosodium L-glutamate monohydrate, MSG monohydrate, sodium glutamate monohydrate, UNII-W81N5U6R6U, L-Glutamic acid, monosodium salt, and monohydrate. Foods that contain these ingredients, of course, aren't necessarily bad for you. Glutamate is a naturally occuring chemical in cheeses, tomatoes, mushrooms, broccoli, peas, and walnuts. Japanese biochemist Kikunae Ikeda first isolated MSG from seaweed in 1908.

Published on Leave a comment on Eating Foods With Turmeric May Be Good For You

The spice turmeric is very popular these days, especially because studies link it to various health benefits. But is this true? Is it better to eat turmeric in foods or take it in pill form as a supplement? Today's post is about a study that was done by the BBC teaming up with researchers at Newcastle University (in the UK) where they looked at whether modest doses of turmeric had health benefits when ingested daily for 6 weeks. Specifically, they looked at what turmeric does to various blood markers thought to be associated with inflammation and changes that could eventually lead to the onset of cancer. It is currently thought that many or turmeric's supposed health benefits come from the compound curcumin found in it.

The researchers took blood samples of 100 volunteers, who were then split up into 3 groups (turmeric powder, a turmeric pill, or a placebo pill daily). Only the group that ingested turmeric in powder form (1 teaspoon mixed in food) showed changes after 6 weeks, and they were exciting beneficial changes in the methylation of DNA. This is because "methylation of the DNA can ‘go wrong’ and this can cause cells to become cancerous".

It's still early days in this research, and more has to be done, but it is exciting. In the meantime, don't take turmeric in pill form, but eat it in foods. It seems that more of the turmeric gets absorbed when eaten with foods, especially foods with fat, and also with a little black pepper. Excerpts from the article written by Michael Mosley, one of the presenters of the broadcast show "Trust Me, I'm A Doctor", from the BBC News:

Could turmeric really boost your health?

Turmeric is a spice which in its raw form looks a bit like ginger root, but when it's ground down you get a distinctive yellowy orange powder that's very popular in South Asian cuisine.....So we tracked down leading researchers from across the country and with their help recruited nearly 100 volunteers from the North East to do a novel experiment. Few of our volunteers ate foods containing turmeric on a regular basis.

Then we divided them into three groups. We asked one group to consume a teaspoon of turmeric every day for six weeks, ideally mixed in with their food. Another group were asked to swallow a supplement containing the same amount of turmeric, and a third group were given a placebo, or dummy pill. The volunteers who were asked to consume a teaspoon of turmeric a day were ingenious about what they added it to, mixing it with warm milk or adding it to yoghurt. Not everyone was enthusiastic about the taste, with comments ranging from "awful" to "very strong and lingering".

But what effect was eating turmeric having on them? We decided to try and find out using a novel test developed at University College, London, by Prof Martin Widschwendter and his team....There are at least 200 different compounds in turmeric, but there's one that scientists are particularly interested in. It gives this spice its colour. It's called curcumin. Thousands of scientific papers have been published looking at turmeric and curcumin in the laboratory - some with promising results. But they've mainly been done in mice, using unrealistically high doses. There have been few experiments done in the real world, on humans.

Prof Widschwendter is not particularly interested in turmeric but he is interested in how cancers start. His team have been comparing tissue samples taken from women with breast cancer and from women without it and they've found a change that happens to the DNA of cells well before they become cancerous. The change is in the "packaging" of the genes. It's called DNA methylation. It's a bit like a dimmer switch that can turn the activity of the gene up or down. The exciting thing is that if it is detected in time this change can, potentially, be reversed, before the cell turns cancerous.

So we asked Prof Widschwendter whether testing the DNA methylation patterns of our volunteers' blood cells at the start and end of the experiment would reveal any change in their risk of cancer and other diseases, like allergies. It was something that had not been done before. Fortunately he was very enthusiastic. "We were delighted," he said, "to be involved in this study, because it is a proof of principle study that opens entirely new windows of opportunity to really look into how we can predict preventive measures, particularly for cancer."

So what, if anything, happened? When I asked him that, he pulled out his laptop and slowly began to speak."We didn't find any changes in the group taking the placebo," he told me. That was not surprising. "The supplement group also didn't also show any difference," he went on. That was surprising and somewhat disappointing.

"But the group who mixed turmeric powder into their food," he continued, "there we saw quite substantial changes. It was really exciting, to be honest. We found one particular gene which showed the biggest difference. And what's interesting is that we know this particular gene is involved in three specific diseases: depression, asthma and eczema, and cancer. This is a really striking finding."

It certainly is. But why did we see changes only in those eating turmeric, not in those taking the same amount as a supplement? Dr Kirsten Brandt, who is a senior lecturer at Newcastle University and who helped run the experiment, thinks it may have something to do with the way the turmeric was consumed. "It could be," she told me, "that adding fat or heating it up makes the active ingredients more soluble, which would make it easier for us to absorb the turmeric.....She also told me, because our volunteers all tried consuming their turmeric in different ways, that we can be confident it was the turmeric that was making the difference and not some other ingredient used to make, say, chicken tikka masala. There is a lot more research that needs to be done, including repeating the experiment to see if these findings can be confirmed.

More information about the study and results from BBC News: Does turmeric really help protect us from cancer?

Published on Leave a comment on Vitamin D Levels and Mental Decline In Older Adults

A new study conducted in China found an association between low vitamin D levels and future cognitive decline in older adults. The lower the vitamin D levels at the initial screening (the baseline), the more people with cognitive decline at a 2 year follow-up. There were were no gender differences. (Another study with similar results.) Vitamin D is produced naturally in the skin when exposed to sunlight, and also found in smaller amounts in food such as fish (e.g. salmon) and eggs. Vitamin D helps maintain healthy bones and muscles, but it also plays a key part in brain function and is viewed as neuroprotective. Low levels are associated with greater risk of cardiovascular and neurodegenerative diseases.

The 1,202 participants (60 years or older) in China had their baseline vitamin D levels measured at the start of the study, and their cognitive abilities assessed over two years. What I found interesting in this study was that the vitamin D levels in the people was in general pretty low - this was without any supplementation, thus from sunlight. The researchers specified vitamin D levels (25-Cholecalciferol) in nmol/l, but in the United States values are generally specified in ng/ml. In the study the median level of vitamin D levels in the lowest quartile converted to ng/ml was 10.0 ng/ml, and in the highest quartile the median level was 26.4 ng/ml. With those low numbers, all 4 groups in the United States would be advised to supplement daily with vitamin D (specifically vitamin D3). From Journals of Gerontology: Medical Sciences:

Vitamin D Levels and the Risk of Cognitive Decline in Chinese Elderly People: the Chinese Longitudinal Healthy Longevity Survey

Vitamin D has a neuroprotective function, potentially important for the prevention of cognitive decline. Prospective studies from Western countries support an association between lower vitamin D level and future cognitive decline in elderly people.

This community-based cohort study of elderly people in China follows 1,202 cognitively intact adults aged ≥60 years for a mean duration of 2 years. Plasma vitamin D level was measured at the baseline. Cognitive state of participants was assessed using the Mini-Mental State Examination (MMSE). Cognitive impairment was defined as an MMSE score <18. Cognitive decline was defined as ≥3 points decline from baseline....Participants with low vitamin D level had an increased risk of cognitive decline. This first follow-up study of elderly people, including the oldest-old, in Asia shows that low vitamin D levels were associated with increased risk of subsequent cognitive decline and impairment.

Vitamin D is a secosteroid hormone necessary for maintaining good musculoskeletal health; its deficiency is associated with increased risks of cardiovascular and neurodegenerative diseases. Vitamin D is primarily synthesized in the skin upon exposure to sunlight; smaller amounts are obtained through dietary intake. More recently, enzymes responsible for the synthesis of its active form have been found to be distributed throughout the human brain.... This growing body of evidence suggests that vitamin D has a neuroprotective function that is potentially important for the prevention of cognitive decline. Although the importance of vitamin D cannot be disregarded, there is still no consensus on its optimal level. This is especially pertinent in the elderly people, the oldest-old in particular, as cutaneous synthesis of vitamin D decreases with age. Moreover, their impaired mobility and limited outdoor activities can further exacerbate vitamin D deficiency.

Cross-sectional studies have generally found a positive association between vitamin D status and cognitive performance in older adults. Recent prospective studies from United States and Europe support an association between diminished vitamin D status and future cognitive decline. Since cutaneous synthesis is the main source of vitamin D, there exists great variability in vitamin D levels across populations due to differences in latitude, seasons, and race/ethnicity, such as level of skin pigmentation.

Our findings were consistent with previous cohort studies showing that vitamin D status predicts cognitive decline....A notable observation in the present study is that the association of vitamin D status and cognitive decline were similar in both oldest-old and less elderly people. In this study, there was a clear association between lower 25(OH)D3 level and cognitive impairment in subjects aged ≥80....An additional difference from previous studies is that the current study indicates that the association between vitamin D and cognitive impairment is not gender specific.

The observation of temporal association between 25(OH)D3 levels and subsequent cognitive function supports the notion that vitamin D has a clinically important neuroprotective effect. A wide variety of mechanisms for this effect has been proposed and is supported by animal studies. Vitamin D has been found to modulate neuronal calcium homeostasis, cerebral process of detoxification, immunomodulation, and beta-amyloid clearance.....Further, it was unlikely that vitamin D supplementation would explain the association in this study, as 87% of the participants reported no use of vitamin supplements....In conclusion, our longitudinal study indicates that low 25(OH) D3 levels are associated with subsequent cognitive decline and cognitive impairment. 

Published on Leave a comment on Selenium, Retinoic Acid, and Cancer Risk

Image result for meat, fish, eggs It is important to eat a varied diet for health, one that focuses on the food groups (and no - cookies and cake are not necessary foods). The first study looks at liver cancer risk and selenium - which is found in fish, shellfish, meat, milk, eggs, and certain South American nuts, such as Brazil nuts. The second article focuses on colorectal cancer and retinoic acid, a compound derived in the body from vitamin A. Vitamin A rich foods can provide you with retinoic acid, such as the lungs, kidneys, and liver of beef, lamb, pork. Also poultry giblets, eggs, cod liver oil, shrimp, fish, fortified milk, butter, cheddar cheese and Swiss cheese. Red and orange vegetables and fruits such as sweet potatoes, squash, carrots, pumpkins, cantaloupes, apricots, peaches and mangoes all contain significant amounts of beta-carotene, thus retinoids. Note that research generally has found health benefits from real foods, not from supplements.

From Science Daily:  Selenium status influence cancer risk

As a nutritional trace element, selenium forms an essential part of our diet. Researchers have been able to show that high blood selenium levels are associated with a decreased risk of developing liver cancer. Selenium (Se) is found in foods like fish, shellfish, meat, milk and eggs; certain South American nuts, such as Brazil nuts, are also good sources of selenium. It is a trace element that occurs naturally in soil and plants, and enters the bodies of humans and animals via the food they ingest. European soil has a rather low selenium concentration, in comparison with other areas of the world, especially in comparison to North America. Deficiencies of varying degrees of severity are common among the general population, and are the reason why German livestock receive selenium supplements in their feed.

While in Europe, neither a selenium-rich diet nor adequate selenium supplementation is associated with adverse effects, selenium deficiency is identified as a risk factor for a range of diseases. "We have been able to show that selenium deficiency is a major risk factor for liver cancer," says Prof. Dr. Lutz Schomburg of the Institute of Experimental Endocrinology, adding: "According to our data, the third of the population with lowest selenium status have a five- to ten-fold increased risk of developing hepatocellular carcinoma -- also known as liver cancer."....Previous studies had suggested a similar relationship between a person's selenium status and their risk of developing colon cancer, as well as their risk of developing autoimmune thyroid disease. (Original study)

From Science Daily: Retinoic acid suppresses colorectal cancer development, study finds

Retinoic acid, a compound derived in the body from vitamin A, plays a critical role in suppressing colorectal cancer in mice and humans, according to researchers at the Stanford University School of Medicine. Mice with the cancer have lower-than-normal levels of the metabolite in their gut, the researchers found. Furthermore, colorectal cancer patients whose intestinal tissues express high levels of a protein that degrades retinoic acid tend to fare more poorly than their peers.

"The intestine is constantly bombarded by foreign organisms," said Edgar Engleman, MD, professor of pathology and of medicine. "As a result, its immune system is very complex. There's a clear link in humans between inflammatory bowel disease, including ulcerative colitis, and the eventual development of colorectal cancer. Retinoic acid has been known for years to be involved in suppressing inflammation in the intestine. We wanted to connect the dots and learn whether and how retinoic acid levels directly affect cancer development."

"We found that bacteria, or molecules produced by bacteria, can cause a massive inflammatory reaction in the gut that directly affects retinoic acid metabolism," said Engleman. "Normally retinoic acid levels are regulated extremely tightly. This discovery could have important implications for the treatment of human colorectal cancer."

Further investigation showed that retinoic acid blocks or slows cancer development by activating a type of immune cell called a CD8 T cell. These T cells then kill off the cancer cells. In mice, lower levels of retinoic acid led to reduced numbers and activation of CD8 T cells in the intestinal tissue and increased the animals' tumor burden, the researchers found. "It's become very clear through many studies that chronic, smoldering inflammation is a very important risk factor for many types of cancer," said Engleman.

Published on Leave a comment on Can Eating A Vegetarian Diet Lower Blood Pressure?

Can eating a vegetarian diet lower blood pressure? Both this review and other reviews of studies say YES, that those following vegetarian diets have a lower prevalence of hypertension. Overall, the mean prevalence of hypertension was 21% in those consuming a vegetarian diet and 29% in those consuming a nonvegetarian diet (the differences varied between studies).Those following a vegetarian diet also tended to have a healthier lifestyle. As the researchers point out: blood pressure medicine lowers blood pressure for one day, while lifestyle changes (diet, exercise, not smoking, limiting or avoiding alcohol) can lower blood pressure for life. From Medscape:

Vegetarian Diet: A Prescription for High Blood Pressure?

Hypertension is one of the most costly and poorly treated medical conditions in the United States and around the world. Consequences of hypertension include morbidity and mortality related to its long-term effects, which include stroke, myocardial infarction, renal failure, limb loss, aortic aneurysm, and atrial fibrillation, among many others. Although there is an armamentarium of medications to treat hypertension, we do little for prevention. In this review we examine the relationship between vegetarian and nonvegetarian diets and the prevalence of hypertension. 

Current nonpharmacologic treatments include: physical activity (≥ 30 minutes of moderate-intensity activity on most days of the week); smoking cessation; dietary modification (lower sodium, increased potassium; mainly plant-based foods; low-fat foods; reduced-fat dairy products; moderate amounts of lean unprocessed meats, poultry, and fish; and moderate amounts of polyunsaturated and monounsaturated fats, such as olive oil); weight reduction; management of stress; and limited alcohol consumption.

It is well known that hypertension is modulated by dietary influences. In this review we examine vegetarian, vegan, and nonvegetarian (omnivore) diets and prevalence of hypertension among these dietary populations. A vegetarian diet (ie, lacto/ovo-vegetarian) includes plant foods, dairy products, and eggs (excludes all meat, such as turkey, beef, poultry, seafood, bacon, etc.). A vegan diet is similar to vegetarian, except it further excludes dairy products and eggs (no animal or animal products). On the other hand, an omnivore diet (referred to as nonvegetarians throughout this study) includes both plant and animal foods and products.....The majority of studies included in this review addressed vegetarians and vegans as a single group (vegetarians), whereas others differentiated them. Vegetarian diets are known to be low in saturated fat and cholesterol, high in fiber, low in sodium, and high in potassium. These key elements have been shown to correlate with lower incidence of cancer, heart disease, and other chronic diseases, such as diabetes type II, hypertension, and hyperlipidemia.

The exact percentage of those following a vegetarian or vegan diet in the US is unknown; however, a 2014 study found that 221 of 11,399 adult respondents, from a group generally representing the demographics of the US, identified as vegan (0.5%), vegetarians (1.5%), or meat-eaters (98%). The prevalence of hypertension in the US in 2011 was roughly 33.8%.

The mean prevalence of hypertension in those consuming a vegetarian diet was 21% and 29% in those consuming a nonvegetarian diet. The overall prevalence of hypertension among vegetarians was 33% lower than nonvegetarian diets. These data support the hypothesis of a decreased prevalence of hypertension in those maintaining a vegan or vegetarian diet versus a nonvegetarian diet, in cross-sectional, cohort, and case-control studies, and in those consuming a vegan or vegetarian diet according to an experimental dietary change. The blood pressure benefit is noted to disappear in those reverting back to a nonvegetarian diet. 

Overall, these findings support previous reviews and meta-analyses of vegetarian and nonvegetarian diets and blood pressure. A recent meta-analysis that identified 39 studies with 21,915 participants concluded vegetarian diets were associated with a drop in mean systolic (-5.9 mm Hg) and diastolic (-3.5 mm Hg) blood pressures when compared with nonvegetarians. Other reviews had similar conclusions, showing that vegetarians have a lower blood pressure compared with nonvegetarians. Of the studies that included a vegan diet separate from other vegetarians (eg, lacto/ovo), the data show a significantly lower prevalence of hypertension when compared with nonvegetarians and other vegetarians. However, limited research has been conducted on strict, consistent vegan diets.

There are possible rationalizations for the observed associations between diet and hypertension. First, vegetarians have a lower rate of smoking tobacco. Smoking can increase blood pressure acutely and chronically over time.....Second, vegetarians tend to drink less alcohol compared with nonvegetarians. Alcohol, specifically ≥ 2 drinks/day, increases blood pressure by causing vasodilation, followed by a compensatory increase in blood pressure.....Further, vegetarians have a lower mean BMI when compared with nonvegetarians, which means a lower overall weight....Fourth, vegetarians tend to exercise more than nonvegetarians. Vegetarians reported a greater incidence of physical activity of ≥ 30 minutes of moderate to vigorous activity per day.

A limitation of this study is that it remains unclear whether vegetarians are more health conscious and therefore live healthier lives, or whether a predominant diet of fruits and vegetables is a basis for lower blood pressure.

Published on Leave a comment on Seafood, DHA Levels, and the Aging Brain

 Eating several servings of seafood (especially fish) weekly has beneficial health effects throughout life, and now research finds another benefit in older adults. Seafood contains both EPA and DHA, which are two types of omega-3 fatty acids. DHA or docosahexanoic acid has "neuroprotective qualities" and is found in both the gray and white matter of the brain. Higher DHA levels (measured in the blood) was associated with better memory, less brain atrophy (better brain volume), and fewer amyloid plaques (which are associated with Alzheimer's) in cognitively healthy older adults. From Medscape:

Higher Serum DHA Linked to Less Amyloid, Better Memory

New research supports neuroprotectant effects of docosahexaenoic acid (DHA) in the aging brain. In a small cross-sectional study of cognitively healthy older adults, higher serum DHA levels were associated with less cerebral amyloidosis, better memory scores, and less regional brain atrophy.

"The interesting finding was the association of low serum DHA levels with cerebral amyloidosis (amyloid plaques) in older adults without evidence of dementia," Hussein N. Yassine, MD, Department of Medicine, University of Southern California, Los Angeles, told Medscape Medical News. "This association was predominantly driven by persons at the lowest quartile of serum DHA levels who likely have limited intake of seafood." "This study adds to the existing evidence on the benefit of seafood consumption on [Alzheimer's disease] AD risk factors," Dr Yassine added.

The study was published online August 8 in JAMA Neurology. In a linked editorial, Joseph F. Quinn, MD, Department of Neurology, Oregon Health and Science University, Portland, notes that DHA is "the most abundant polyunsaturated fatty acid in the brain, playing an important structural role in synapses while also modulating a number of signaling pathways. "Brain DHA levels are also modulated by dietary intake, so it is plausible for dietary DHA to alter brain concentrations and affect downstream targets including brain pathology and function."

Dr Yassine and colleagues assessed serum DHA levels, measures of amyloid burden based on positron emission tomography with Pittsburgh compound B, brain volume, and neuropsychological test scores in 61 adults without dementia in the Aging Brain Study.

They found that serum DHA levels (percentage of total fatty acids) were 23% lower in those with cerebral amyloidosis relative to those without. Serum DHA levels were inversely correlated with brain amyloid load, independent of age, sex, years of education, and apolipoprotein E genotype. They also noted a positive correlation between serum DHA levels and brain volume in several subregions affected by AD, in particular the left subiculum and the left entorhinal volumes.

Clinically, there was a significant association between serum DHA levels and nonverbal memory. This association persisted after adjustment for age but not after adjustment for apolipoprotein E genotype. Serum DHA levels were not associated with measures of global cognition, executive function, or verbal memory scores.