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Published on Leave a comment on Should Pregnant Women Be Warned To Avoid Licorice?

Avoid eating licorice during pregnancy? That licorice is a food to avoid during pregnancy (or only eat in tiny amounts) will be news to many. Most people think of licorice (or liquorice) as a candy, but it can also be used as a herbal medicine that can have negative health effects, especially in large doses (e.g, high blood pressure, loss of potassium). The licorice flavor comes from the root of the plant (licorice root). Licorice contains glycyrrhizin, which is in black licorice candy, and in some chewing gums, ice creams, syrups, soft drinks, supplements, herbal teas, and other products.

In 2016, the government of Finland warned against consuming licorice (including black licorice and salty licorice) during pregnancy. In the United States, the FDA does not warn pregnant women about eating licorice or licorice root. The National Institutes of Health (NIH) recommends that pregnant women avoid consuming large amounts of licorice root in food or taking it as a supplement. But how about small amounts of licorice? And what are possible effects during pregnancy?

A recent study in Finland compared children (average age of 12 1/2 years) whose mothers had either consumed little to no licorice during pregnancy or had consumed large amounts of licorice (high glycyrrhizin levels were calculated as more than 500 milligrams per week). Note that 500 mg glycyrrhizin is equal to 250 grams or 8.8 oz licorice. The researchers found that children whose mothers ate large amounts of licorice during pregnancy  were about 7 points lower on IQ tests, had poorer memory, and had higher rates of attention deficit/hyperactivity disorder problems than those whose mothers had eaten little or no licorice during pregnancy. High-consumption group girls had earlier and more advanced puberty, and were taller and heavier than those in the low-licorice group.

The researchers wrote that glycyrrhizin results in "glucocorticoid overexposure", which may affect the developing fetus, and the effects persist into early adolescence. The study researchers concluded that pregnant women should be informed that consumption of licorice and other food products containing glycyrrhizin may be associated with harm to their developing baby. A little licorice candy here and there during pregnancy seems to be OK (so don't panic!), but licorice or licorice root is not something that should be eaten or drunk (e.g.,in a tea) regularly. From Science Daily:

Pregnant women should avoid liquorice

A new Finnish study supports food recommendations for families with children in that women should avoid consuming large amounts of liquorice during pregnancy. The limit for safe consumption is not known. In the study, youths that were exposed to large amounts of liquorice in the womb performed less well than others in cognitive reasoning tests carried out by a psychologist. The difference was equivalent to approximately seven IQ points. Those exposed to liquorice also performed less well in tasks measuring memory capacity, and according to parental estimates, they had more ADHD-type problems than others. With girls, puberty had started earlier and advanced further.

The Glaku study carried out by the University of Helsinki, the National Institute for Health and Welfare and the Helsinki and Uusimaa hospital districts compared 378 youths of about 13 years whose mothers had consumed "large amounts" or "little/no" liquorice during pregnancy. In this study a large amount was defined as over 500 mg and little/no as less than 249 mg glycyrrhizin per week. These cutoffs are not based on health effects. 500 mg glycyrrhizin corresponds on average to 250 g liquorice.

Researchers suggest that pregnant women and women planning pregnancy should be informed of the harmful effects that products containing glycyrrhizin -- such as liquorice and salty liquorice -- may have on the fetus. In Finland, this is already reality. In January 2016, the National Institute for Health and Welfare published food recommendations for families with children, in which liquorice was placed in the 'not recommended' category for pregnant women. According to the recommendations, occasional consumption of small amounts such as a portion of liquorice ice cream or a few liquorice sweets is not dangerous.

As a result of animal experiments, the biological mechanism of the effects of liquorice is well known. Glycyrrhizin intensifies the effects of stress hormone cortisol by inhibiting the enzyme that inactivates cortisol. While cortisol is essential to the development of a fetus, it is detrimental in large amounts. It has long been known that glycyrrhizin causes higher blood pressure and shorter pregnancies in humans, but such long-lasting effects on the fetus have not been proven before. [Original study.]

Published on Leave a comment on Eating An Egg A Day May Be Beneficial?

Remember all the dietary advice that for years told us to avoid or limit consumption of eggs - that since they were high in cholesterol, they were bad for us and would increase our risk for heart disease? And the nonsense that we should only eat the egg whites while throwing out the yolks? Hah...That advice was wrong, which another recent study confirms.

Eggs are an amazingly nutritious food. They’re loaded with high quality protein, healthy fats, vitamins, minerals, high in choline (a brain nutrient), biotin, antioxidants, lutein, and zeaxanthin. One review of studies (involving millions of people) looked at whole egg consumption  and found that high egg consumption (up to one egg per day) is not associated with increased risk of coronary heart disease or stroke, and in fact there was a reduced risk of hemorrhagic stroke. Only among diabetics was there an elevated risk of coronary heart disease with high egg consumption (up to 1 egg per day). Another study found a lower risk of type 2 diabetes in middle-aged men (see post).

A recent study from Finland found that neither cholesterol nor egg intake (eating one egg per day) was associated with an increased risk of dementia or Alzheimer's disease in Finnish men who were followed for 22 years. Instead, eating eggs was associated with better cognitive performance in certain areas such as executive function, which includes memory, problem solving, and planning (they were given neuropsychological tests). From Science Daily:

High cholesterol intake and eggs do not increase risk of memory disorders

A new study from the University of Eastern Finland shows that a relatively high intake of dietary cholesterol, or eating one egg every day, are not associated with an elevated risk of dementia or Alzheimer's disease. Furthermore, no association was found in persons carrying the APOE4 gene variant that affects cholesterol metabolism and increases the risk of memory disorders. APOE4 is common in Finland.

The dietary habits of 2,497 men aged between 42 and 60 years and with no baseline diagnosis of a memory disorder were assessed at the onset the Kuopio Ischaemic Heart Disease Risk Factor Study, KIHD, in 1984-1989 at the University of Eastern Finland. During a follow-up of 22 years, 337 men were diagnosed with a memory disorder, 266 of them with Alzheimer's disease. 32.5 per cent of the study participants were carriers of APOE4.

The study found that a high intake of dietary cholesterol was not associated with the risk of dementia or Alzheimer's disease -- not in the entire study population nor in the carriers of APOE4. Moreover, the consumption of eggs, which are a significant source of dietary cholesterol, was not associated with the risk of dementia or Alzheimer's disease. On the contrary, the consumption of eggs was associated with better results in certain tests measuring cognitive performance. 

Published on Leave a comment on Environmental Pollutants and Gut Microbes

What things in our environment have an effect on the microbes living within us? We now know that gut microbes are important for our health in many ways, and that thousands of species of bacteria, as well as viruses, fungi, and other microbes normally live in a healthy person's gut. We refer to these microbes as the human microbiota or human microbiome. When the community of gut microbes is thrown out of whack (dysbiosis) there can be a number of negative health effects, including diseases. Researchers are just learning about all the microbes within us and their importance in health and disease. [See all posts on the human microbiome.]

Past posts have discussed such things as antibiotics, emulsifiers, different foods and diets, heartburn drugs, etc. having an effect on the human microbiome, but what else? A recent study from China reviewed some environmental pollutants and their effects on gut microbiota - as shown in both human and animal studies. They reviewed studies on antibiotics, heavy metals (arsenic, cadmium, lead), persistant organic pollutants or POPs (organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers, and polycyclic aromatic hydrocarbons or PAHs), pesticides (permethrin, chlorpyrifos, pentachlorophenol, epoxiconazole and carbendazim, imazalil), emulsifiers, nanoparticles (e.g., silver nanoparticles), and artificial sweeteners. They found that all these environmental pollutants had effects on gut microbes - with some effects lasting for years. Their conclusion: gut microbes are very sensitive to drugs, diet, and environmental pollutants. By the way, notice that popular food ingredients such as emulsifiers and artificial sweeteners were considered "environmental pollutants" by the researchers.

Excerpts from Environmental Pollution: Effects of environmental pollutants on gut microbiota

Environmental pollutants have become an increasingly common health hazard in the last several decades. Recently, a number of studies have demonstrated the profound relationship between gut microbiota and our health. Gut microbiota are very sensitive to drugs, diet, and even environmental pollutants. In this review, we discuss the possible effects of environmental pollutants including antibiotics, heavy metals, persistent organic pollutants, pesticides, nanomaterials, and food additives on gut microbiota and their subsequent effects on health. We emphasize that gut microbiota are also essential for the toxicity evaluation of environmental pollution. In the future, more studies should focus on the relationship between environmental pollution, gut microbiota, and human health.

Thousands of species are found in the gut microbiome, and the majority of these species belong to six bacterial phyla: Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, Fusobacteria, and Verrucomicrobia (Eckburg et al., 2005). Gut microbiota are highly dynamic and have substantial interindividual and intraindividual variation....The gut microbiota are very essential for host health. They participate in the regulation of many physiological functions. The gut microbiota reside in our intestinal mucus layer and even participate in shaping the mucus layer (Jakobsson et al., 2015). They help us to digest food (such as fiber); synthesize vitamins and amino acids (Spanogiannopoulos et al., 2016); play very important roles in energy metabolism and storage, immune system modulation, growth, and neurodevelopment; and can even regulate our behavior.... The occurrence of many diseases is correlated with altered gut microbiome composition (Lange et al., 2016). Gut microbiota dysbiosis is considered to be a potential cause of obesity (Cani et al., 2007; Fei and Zhao, 2013). However, gut microbiota are very sensitive to drugs, diet, and environmental pollutants.

Although most environmental pollutants do not directly target gut microbiota, some pollutants can enter the body and interact with the gut microbiota through different pathways. A number of previous studies have shown that exposure to environmental pollutants can alter the composition of the gut microbiome, leading to disorders of energy metabolism, nutrient absorption, and immune system function or the production of other toxic symptoms (Jin et al., 2015c; Zhang et al., 2015b). In the present review, we conclude that different kinds of environmental pollutants can induce gut microbiota dysbiosis and have multiple potential adverse effects on animal health. 

Heavy metals in the environment have become a severe health risk in recent years (Liu et al., 2016a). As a common form of environmental pollution, heavy metals are associated with a wide range of toxic effects, including carcinogenesis, oxidative stress, and DNA damage, and effects on the immune system..... Recently, several studies have stated that heavy metal exposure could also lead to gut microbiota dysbiosis, indicating that study of gut microbiota provides a new approach to analyze the mechanisms of heavy metal toxicity

Immune system function is tightly coupled to our gut microbiome. Gut microbiota and their metabolites can interact with both the innate immune system and the adaptive immune system (Honda and Littman, 2016; Thaiss et al., 2016).... Alterations in the gut microbiome can disrupt the balance between the host immune system and gut microbiota, induce immune responses, and even trigger some immunological diseases. Furthermore, immune system imbalance may influence the microbiota metabolites. For example, trimethylamine, which is absorbed from food by gut microbiota, can induce atherosclerosis (Chistiakov et al., 2015).

Published on Leave a comment on Vitamin D and Frequent Headaches

I saw mention of this study in a number of places - that low vitamin D levels are linked to chronic headaches. A little too soon to know if that is really true -  the researchers in this study looked at the blood vitamin D levels of 2601 men just one time, and did not give vitamin D supplements to the men to see if this changed the frequency of migraine headaches. The researchers themselves pointed out that other studies looking at this same issue have had mixed results. And they themselves pointed out that low blood levels of vitamin D (serum 25(OH)D concentration) was associated with a markedly higher risk of frequent headache in men. Associated does not mean caused.

Yes, low vitamin D levels is linked to a number of health problems (see all vitamin D posts). But at this point I think that it's a case of "wait and see" to see if vitamin D levels have something to do with headache frequency. Perhaps other micronutrients are important, perhaps something else. Note that in the study they used below 50 nmol as the measure for low vitamin D levels. In the USA, that translates into below 20 ng/ml, which everyone agrees is too low (a deficiency). The best source of vitamin D is sunlight - which is why it's called the "sunshine vitamin". From Science Daily:

Vitamin D deficiency increases risk of chronic headache

Vitamin D deficiency may increase the risk of chronic headache, according to a new study from the University of Eastern Finland....The Kuopio Ischaemic Heart Disease Risk Factor Study, KIHD, analysed the serum vitamin D levels and occurrence of headache in approximately 2,600 men aged between 42 and 60 years in 1984-1989. In 68% of these men, the serum vitamin D level was below 50 nmol/l, which is generally considered the threshold for vitamin D deficiency. Chronic headache occurring at least on a weekly basis was reported by 250 men, and men reporting chronic headache had lower serum vitamin D levels than others.

When the study population was divided into four groups based on their serum vitamin D levels, the group with the lowest levels had over a twofold risk of chronic headache in comparison to the group with the highest levels. Chronic headache was also more frequently reported by men who were examined outside the summer months of June through September. Thanks to UVB radiation from the sun, the average serum vitamin D levels are higher during the summer months.

The study adds to the accumulating body of evidence linking a low intake of vitamin D to an increased risk of chronic diseases. Low vitamin D levels have been associated with the risk of headache also by some earlier, mainly considerably smaller studies.

Published on Leave a comment on Focus On Healthy Lifestyle, Not Just On Tests And Screenings

The wonderful blog posts of Dr. John Mandrola (physician, blogger, and columnist at Medscape) are always thoughtful, and this latest points out things a number of studies have pointed out for a while. Which is to stop obsessing or focusing on "preventive tests" and screenings and numbers, and instead focus on a healthy lifestyle - which means getting regular exercise or physical activity, don't smoke cigarettes, maintaining a healthy weight, and eating a healthy diet with lots of fruits, vegetables, nuts, seeds, whole grains, and legumes (think Mediterranean-style diet).

Don't want overdiagnosis and overtreatment (here, here, here, and here). Excerpts from Dr. John M:

I am changing…

The main thing that has changed about me is my views as a doctor, especially when it comes to dealing with people who complain of nothing. Medicine is most pure when we treat people with illness. The infirmed come to us with a problem and we use our intelligence, experience and procedural skills to help them. It’s immensely gratifying. The joy of helping people still negates the stifling burden of administrative nonsense. I’ll do your damn corporate safety modules one more year because helping sick people get well feels so good.

But when people complain of nothing, our first job is to do no harm. I know prevention of disease is better than treating it, but the process of prevention gets dicey. When we prescribe things (screening tests, statins, aspirin, diabetes drugs etc) to people who complain of nothing, we should have the highest evidence these therapies deliver benefit. Too often, we cite eminence rather than evidence.

I’ve come to believe the medical profession is too paternalistic, too arrogant. I fear the medicalization of the human condition. These days, I order fewer tests. Medical tests put people into the “system,” on the metaphorical train of healthcare. This train accelerates quickly, and it’s often hard to get off. Even a simple echo scares me. I could tell you stories.

More often than not, I tell patients to stop checking their “numbers.” If they insist on health numbers, I favor three–the scale, the belt size and a Timex to measure walking speed.

A 2002 article from Dr. David Sackett (a pioneer of evidence-based medicine) perfectly captures my views on preventive medicine. It’s called The Arrogance of Preventive Medicine. It’s worth a look, now more than ever.

Published on Leave a comment on Heart Attacks Run In The Family? Healthy Lifestyle Can Really Reduce Risk

 Image result for human heart in human body wikipedia Heart attacks run in the family? Does this mean you are doomed to also have a heart attack? Well, the good news from a large study is that a healthy lifestyle (with at least 3 of these 4 behaviors: not currently smoking, not being obese, regular physical activity at least once per week, and eating a good diet)  lowers the risk of a heart attack by nearly 50% even in those with a high genetic risk for heart attacks. (This is compared to those with an unhealthy lifestyle, which is none or only one healthy behavior.)  In this study a healthy diet was one with lots of fruits, nuts, vegetables, whole grains, fish, and dairy products, and a reduced amount of refined grains, processed meats, red meat, sugar-sweetened beverages, and trans fats.

The researchers also reversed the question and asked: "If you happen to inherit good genes, can a bad lifestyle offset that? We actually found yes." The risk of heart attack is also reduced nearly 50% in those people with good genes and a good lifestyle. BOTTOM LINE: Healthy lifestyle counts, no matter whether heart disease and heart attacks run in the family or not. There is an interaction between the two, From Science Daily:

Following a healthy lifestyle can greatly reduce genetic heart attack risk

It is well known that following a healthy lifestyle -- not smoking, avoiding excess weight and getting regular exercise -- can reduce the risk of heart disease. But what about people who have inherited gene variants known to increase risk? A study led by Massachusetts General Hospital (MGH) investigators has found that, even among those at high genetic risk, following a healthy lifestyle can cut in half the probability of a heart attack or similar event. 

"The basic message of our study is that DNA is not destiny," says Sekar Kathiresan, MD...."Many individuals -- both physicians and members of the general public -- have looked on genetic risk as unavoidable, but for heart attack that does not appear to be the case."  

In order to investigate whether a healthy lifestyle can mitigate genetic risk, the multi-institutional research team analyzed genetic and clinical data from more than 55,000 participants in four large-scale studies. Three of these studies....followed participants for up to 20 years. Each participant in the current analysis was assigned a genetic risk score....The investigators used four AHA-defined lifestyle factors -- no current smoking; lack of obesity (defined as a body mass index less than 30); physical exercise at least once a week; and a healthy dietary pattern -- to determine a lifestyle score, whether participants had a favorable (three or four healthy factors), intermediate (two factors) or unfavorable (one or no healthy factors) lifestyle.

Across all three prospective studies, a higher genetic risk score significantly increased the incidence of coronary events -- as much as 90 percent in those at highest risk. While known risk factors such as a family history and elevated LDL cholesterol were also associated with an elevated genetic risk score, genetic risk was the most powerful contributor to cardiac risk. Similarly, each healthy lifestyle factor reduced risk, and the unfavorable lifestyle group also had higher levels of hypertension, diabetes and other known risk factors upon entering the studies.

Within each genetic risk category, the presence of lifestyle factors significantly altered the risk of coronary events to such an extent that following a favorable lifestyle could reduce the incidence of coronary events by 50 percent in those with the highest genetic risk scores. Among participants in the BioImage study, both genetic and lifestyle factors were independently associated with levels of calcium-containing plaque in the coronary arteries, and healthy lifestyle factors were associated with less extensive plaque within each genetic risk group. [Original study]

Published on Leave a comment on Vegan Diets During Pregnancy?

I've been asked whether vegan diets are safe during pregnancy. And I've always said that I don't know, but that avoiding all meat, fish, eggs, and dairy concerns me. Vegan diets are diets without meat, fish, dairy, honey, and eggs (no animal derived food), but while vegetarian diets also avoid meat, they do include eggs, honey, milk, and dairy products. Thus it is very important that anyone following a vegan diet plan meals carefully to get all the necessary nutrients. For example, soda and french fries are vegan, but are not good nutritionally.

There are a number of nutrients that probably need to be supplemented in vegan diets during pregnancy, especially B-12, iron, zinc, iodine (can get by using iodized salt), and omega-3s, and that's not even discussing micronutrients. So it was good to see this article by Dr. Drew Ramsey (Columbia University, NY) raising those same concerns about nutrient deficiencies during pregnancy, and pointing out that very few studies have looked at vegetarian and vegan diets in pregnancy - that the evidence is "scant". This topic is so controversial that as of today there were 85 comments by health professionals after the following Medscape article - both strongly pro and con, and studies given that show that vegans tend to have lower levels of a number of nutrients measured (zinc, iron, omega-3s, etc).

There are also reports of babies exclusively breast-fed by vegan mothers (here and here) who did not take vitamin supplements that developed nutritional deficiencies (especially B-12, vitamin K, and vitamin D). This is because what a mother eats is what the baby gets during pregnancy and breast-feeding.

On the other hand, the Academy of Nutrition and Dietetics came out with a position statement in 2016 stating that "appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes". But that article (in the Journal of Academy of Nutrition and Dietetics) then goes on in depth about several nutrients that can be lower or deficient in vegan diets unless supplements are given (B-12, iodine, etc). From Medscape;

Are Vegan and Vegetarian Diets Safe During Pregnancy?

Are vegan and vegetarian diets safe during pregnancy?....Vegan and vegetarian diets are plant-based diets....Plants, in general, are a great choice, especially colorful plants, because they tend to be more nutrient-dense. Plant-based diets have been linked to a number of health benefits, such as lower body mass index and lower rates of obesity and diabetes, as well as conferring some benefits. Certainly, vegan and vegetarian diets have higher amounts of certain nutrients like magnesium, folate, and fiber, all of which are generally consumed in very low quantities in Western diets.

Focusing on pregnancy, there are two important papers to note. The first, which got me very interested in this issue, was a series of pooled case reports by Drs Dror and Allen in 2008.[1] They looked at 30 cases of severe vitamin B12 deficiency during pregnancy in vegan women with pernicious anemia. Among the 30 vegan women who had B12 deficiency during pregnancy, about 60% of their offspring had severe developmental delays and 37% had cerebral atrophy.... The clinical importance of this is to partner with our patients who are eating plant-based diets and ensure that they have adequate levels of vitamin B12, as well as iron, zinc, and long-chain omega-3 fats during pregnancy.

The second article to take a peek at is from the British Journal of Obstetrics and Gynaecology in 2015.[2] This was a systematic review that looked at all of the literature after screening out the papers. The authors found about 13 papers focusing on maternal and infant outcomes, and about nine of those looked at nutrient deficiency. The main headline of this review is that there are no randomized clinical trials of vegan or vegetarian diets in pregnancy. It is very hard to make a clear clinical recommendation. The epidemiologic data were heterogeneous. As the researchers called it, it was "scant." That is certainly true. Overall, there were no clear associations with bad outcomes. There was some increased risk for hypospadias in one of the larger trials that looked at vegan and vegetarian diets during pregnancy.

The main concern is that vegan and vegetarian diets put patients at risk for a number of nutrient deficiencies—vitamin B12 in vegan diets (and even for vegetarians), iron, zinc, and the long-chain omega-3 fats. Just a quick moment on the long-chain omega-3 fats: Dietarily, these only come from fatty fish and seafood. They are bioconcentrated. They start in algae, but they get bioconcentrated in our food supply via seafood. It is very hard to get those during pregnancy. Certainly, a lot of healthy babies have been born to vegetarian and vegan women. You can supplement, but given the benefits we see with omega-3 fats in patients with things like mood disorders or a history of psychotic disorders, I think it is important to consider the long-chain omega-3 fats. If someone is not going to get those in their diet but has a history, risk, or propensity toward mood disorders, think about supplementation. 

Excerpts from the review study (mentioned above) in BJOG: Vegan-vegetarian diets in pregnancy: danger or panacea? A systematic narrative review.

To review the literature on vegan-vegetarian diets and pregnancy outcomes [in healthy pregnant women]....None of the studies reported an increase in severe adverse outcomes or in major malformations, except one report of increased hypospadias in infants of vegetarian mothers. Five studies reported vegetarian mothers had lower birthweight babies, yet two studies reported higher birthweights. The duration of pregnancy was available in six studies and was similar between vegan-vegetarians and omnivores. The nine heterogeneous studies on microelements and vitamins suggest vegan-vegetarian women may be at risk of vitamin B12 and iron deficiencies.

CONCLUSIONS: The evidence on vegan-vegetarian diets in pregnancy is heterogeneous and scant. The lack of randomised studies prevents us from distinguishing the effects of diet from confounding factors. Within these limits, vegan-vegetarian diets may be considered safe in pregnancy, provided that attention is paid to vitamin and trace element requirements.

Published on Leave a comment on Good Reason To Eat Vegetables Daily

New research further confirms a link between higher lutein levels (as measured in the blood) and the preservation of "crystallized intelligence" in older adults.  Crystallized intelligence is the ability to use the skills and knowledge one has acquired over a lifetime. Lutein is in foods such as leafy green vegetables, cruciferous vegetables (broccoli, brussels sprouts, cauliflower, and cabbage) and egg yolks. Lutein is also found in small amounts in other fruits and vegetables. Bottom line: eat a variety of fresh fruits and vegetables daily. [Original study.]Medical Xpress:

Study links nutrition to brain health and intelligence in older adults

A study of older adults links consumption of a pigment found in leafy greens to the preservation of "crystallized intelligence," the ability to use the skills and knowledge one has acquired over a lifetime.

Lutein (LOO-teen) is one of several plant pigments that humans acquire through the diet, primarily by eating leafy green vegetables, cruciferous vegetables such as broccoli, or egg yolks, said University of Illinois graduate student Marta Zamroziewicz, who led the study with Illinois psychology professor Aron Barbey. Lutein accumulates in the brain, embedding in cell membranes, where it likely plays "a neuroprotective role," she said. "Previous studies have found that a person's lutein status is linked to cognitive performance across the lifespan," Zamroziewicz said. 

The study enrolled 122 healthy participants aged 65 to 75 who solved problems and answered questions on a standard test of crystallized intelligence. Researchers also collected blood samples to determine blood serum levels of lutein and imaged participants' brains using MRI to measure the volume of different brain structures. The team focused on parts of the temporal cortex, a brain region that other studies suggest plays a role in the preservation of crystallized intelligence.

The researchers found that participants with higher blood serum levels of lutein tended to do better on tests of crystallized intelligence. Serum lutein levels reflect only recent dietary intakes, Zamroziewicz said, but are associated with brain concentrations of lutein in older adults, which reflect long-term dietary intake. Those with higher serum lutein levels also tended to have thicker gray matter in the parahippocampal cortex, a brain region that, like crystallized intelligence, is preserved in healthy aging, the researchers report..... "Our findings do not demonstrate causality," Zamroziewicz said. "We did find that lutein is linked to crystallized intelligence through the parahippocampal cortex."

Published on Leave a comment on Are You Getting Enough Magnesium?

Magnesium is a mineral found in the human body that is necessary for good health. New research analysed 40 studies and found that a diet rich in magnesium is associated with a reduced risk of stroke, heart failure, diabetes, and death ("all cause mortality").

Even though there are many magnesium rich foods, it is estimated that many people don't get enough magnesium in the diet, especially if they eat a lot of processed, low-fiber foods. Current Recommended Dietary Allowances (RDAs) are 320 mg daily for adult females and 420 mg daily for adult males (NIH magnesium fact-sheets - here and here). Especially good sources of magnesium are green leafy vegetables, legumes (beans), nuts, seeds, chocolate, and whole grains. In general, foods containing dietary fiber provide magnesium.From EurekAlert:

Dietary magnesium associated with reduced risk of heart disease, stroke and diabetes

A diet rich in magnesium may reduce the risk of diseases including coronary heart disease, stroke and type-2 diabetes according to a new meta-analysis published in the open access journal BMC Medicine. This analysis of the evidence on dietary magnesium and health outcomes is the largest to date, involving data from more than one million people across nine countries.

The researchers, from Zhejiang University and Zhengzhou University in China, found that people in the highest category of dietary magnesium consumption had a 10% lower risk of coronary heart disease, 12% lower risk of stroke and a 26% lower risk of type-2 diabetes compared to those in the lowest category. Their results also indicate that an extra 100 mg per day of dietary magnesium could also reduce risk of stroke by 7% and type-2 diabetes by 19%.

Magnesium is vital for human health and normal biological functions including glucose metabolism, protein production and synthesis of nucleic acids such as DNA. Diet is the main source of magnesium as the element can be found in foods such as spices, nuts, beans, cocoa, whole grains and green leafy vegetables.

Original study. from BMC Medicine: Dietary magnesium intake and the risk of cardiovascular disease, type 2 diabetes, and all-cause mortality: a dose–response meta-analysis of prospective cohort studies

Increasing dietary magnesium intake is associated with a reduced risk of stroke, heart failure, diabetes, and all-cause mortality, but not CHD [coronary heart disease] or total CVD [cardiovascular disease]. These findings support the notion that increasing dietary magnesium might provide health benefits....Magnesium is essential to all living organisms, as it controls the function of many crucial enzymes, including those that utilize or synthesize ATP ....

Published on Leave a comment on A Daily Handful of Nuts Keeps the Doctor Away?

A large review of nut studies found that people eating a daily handful of nuts (about 20 g) have a lower risk of heart disease, cancer, stroke, premature death, and death from respiratory disease, type 2 diabetes, and infectious disease. Truly impressive. Benefits seem to be for all nuts, and also peanuts - which are called nuts, but are actually legumes (other posts about nut consumption benefits). An earlier post discussed how some of these effects could be to nuts lowering systemic inflammation throughout the body. Bottom line: try to eat a handful of nuts every day or most days a week for your health. And make it a variety of nuts - walnuts, almonds, hazelnuts, cashews, pistachios, pecans, Brazil nuts, and peanuts. From Science Daily:

A handful of nuts a day cuts the risk of a wide range of diseases

A large analysis of current research shows that people who eat at least 20g of nuts a day have a lower risk of heart disease, cancer and other diseases. The analysis of all current studies on nut consumption and disease risk has revealed that 20g a day -- equivalent to a handful -- can cut people's risk of coronary heart disease by nearly 30 percent, their risk of cancer by 15 percent, and their risk of premature death by 22 percent. An average of at least 20g of nut consumption was also associated with a reduced risk of dying from respiratory disease by about a half, and diabetes by nearly 40 percent, although the researchers note that there is less data about these diseases in relation to nut consumption.

The study, led by researchers from Imperial College London and the Norwegian University of Science and Technology, is published in the journal BMC Medicine. The research team analysed 29 published studies from around the world that involved up to 819,000 participants, including more than 12,000 cases of coronary heart disease, 9,000 cases of stroke, 18,000 cases of cardiovascular disease and cancer, and more than 85,000 deaths. While there was some variation between the populations that were studied....the researchers found that nut consumption was associated with a reduction in disease risk across most of them.

The study included all kinds of tree nuts, such as hazel nuts and walnuts, and also peanuts -- which are actually legumes. The results were in general similar whether total nut intake, tree nuts or peanuts were analysed. What makes nuts so potentially beneficial, said Aune, is their nutritional value: "Nuts and peanuts are high in fibre, magnesium, and polyunsaturated fats -- nutrients that are beneficial for cutting cardiovascular disease risk and which can reduce cholesterol levels. "Some nuts, particularly walnuts and pecan nuts are also high in antioxidants, which can fight oxidative stress and possibly reduce cancer risk. Even though nuts are quite high in fat, they are also high in fibre and protein, and there is some evidence that suggests nuts might actually reduce your risk of obesity over time."

The study also found that if people consumed on average more than 20g of nuts per day, there was little evidence of further improvement in health outcomes. [ORIGINAL STUDY]