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The spice turmeric is a very popular supplement nowadays, believed to have all sorts of health benefits due to the curcumin in it (e.g. that it is anticancer, anti-Alzheimer's, anti inflammatory). And yes, studies in the lab (in vitro and in vivo) look very promising. However, a large 2017 review of existing studies also found evidence that "curcumin is unstable under physiological conditions and not readily absorbed by the body, properties that make it a poor therapeutic candidate". In other words, the hype for curcumin supplements is not matching the reality, especially or probably because it is so poorly absorbed by humans. But researchers keep trying. And keep in mind that turmeric has other compounds in it also - it is not just curcumin and nothing else.

A "double-blind, placebo-controlled clinical trial" is the best evidence for something being effective. That means a study where people are randomly assigned to groups, no one actually knows who is getting what, and there is a placebo group that is getting a "sham" treatment. A recent study did exactly that in testing a new formulation of curcumin (Theracurmin) that was easily absorbed (bioavailable) by the persons participating in the study.

And yes - they found health benefits, specifically improvements in memory and attention in those persons taking the curcumin supplements over a 18 month period (as compared to those taking a placebo and whose memory and attention deteriorated over that time). The subjects (who were between 50 and 90 years of age) did not have dementia at the start of the study, but were showing signs of "normal aging" or had mild neurocognitive disorder. Brain scans (before and after treatment) suggested that the behavioral and cognitive benefits from curcumin were associated with "decreases in plaque and tangle accumulation in brain regions moduating mood and memory" - so it had anti-inflammatory and/or anti-amyloid brain effects.

So...  Stay tuned. Meanwhile, perhaps frequent eating of foods containing turmeric may also have beneficial effects, as some studies suggest. From Science Daily:

Curcumin improves memory and mood

Lovers of Indian food, give yourselves a second helping: Daily consumption of a certain form of curcumin -- the substance that gives Indian curry its bright color -- improved memory and mood in people with mild, age-related memory loss, according to the results of a study conducted by UCLA researchers. .... Found in turmeric, curcumin has previously been shown to have anti-inflammatory and antioxidant properties in lab studies. It also has been suggested as a possible reason that senior citizens in India, where curcumin is a dietary staple, have a lower prevalence of Alzheimer's disease and better cognitive performance.

The double-blind, placebo-controlled study involved 40 adults between the ages of 50 and 90 years who had mild memory complaints. Participants were randomly assigned to receive either a placebo or 90 milligrams of curcumin twice daily for 18 months. All 40 subjects received standardized cognitive assessments at the start of the study and at six-month intervals, and monitoring of curcumin levels in their blood at the start of the study and after 18 months. Thirty of the volunteers underwent positron emission tomography, or PET scans, to determine the levels of amyloid and tau in their brains at the start of the study and after 18 months.

The people who took curcumin experienced significant improvements in their memory and attention abilities, while the subjects who received placebo did not, Small said. In memory tests, the people taking curcumin improved by 28 percent over the 18 months. Those taking curcumin also had mild improvements in mood, and their brain PET scans showed significantly less amyloid and tau signals in the amygdala and hypothalamus than those who took placebos. The amygdala and hypothalamus are regions of the brain that control several memory and emotional functions. [Original study.]

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?

The following article excerpts are from the talk "Food and Brain" about the best foods for the brain, at the annual 2015 meeting of the American Psychiatric Association (APA). This is in the new emerging field of food psychiatry, or how certain foods and diet influence the brain. The data is emerging that we can positively influence mental health through dietary interventions. For ex.: recent work reported that adults who followed the Mediterranean dietary pattern the closest over 4.4 years had a significantly reduced risk of developing depression (by 40% to 60%).

One key comment was: "Perhaps diet is the closest we've come to prevention in psychiatry." Some foods that are especially beneficial for the brain: seafood, greens, nuts, legumes (beans) and occasional dark chocolate. Use smaller amounts of meat (more as flavorings rather than just eating huge chunks of it) on top of a plant based diet. Also mentioned were the benefits of turmeric (because of the curcumin in it) and rosemary. And focus on improving the whole dietary pattern rather than just eating or not eating certain foods.

Note that BDNF is Brain-derived neurotrophic factor. This is a protein that acts on the brain, the nervous system, and it is very important for learning, memory, and higher thinking. So increasing BDNF levels is good. And remember, what's good for the brain is also good for the body and microbes - it's all intertwined. From Medscape:

Beans, Greens, and the Best Foods For the Brain

Dr Ramsey, in collaboration with the new International Society for Nutritional Psychiatry, is in the process of developing a standardized "brain food diet." "Food is a very effective and underutilized intervention in mental health," he started off. "We want to help our patients have more resilient brains by using whole helping get patients off of processed foods, off of white carbohydrates, and off of certain vegetable oils."

Though the field is in its infancy, food psychiatry is increasingly being embraced by clinicians and researchers, as a paper published earlier this year in the Lancet Psychiatry attests. "Although the determinants of mental health are complex," the authors wrote, "the emerging and compelling evidence for nutrition as a crucial factor in the high prevalence and incidence of mental disorders suggests that diet is as important to psychiatry as it is to cardiology, endocrinology, and gastroenterology." ..."The data are very promising that we can positively influence mental health through dietary interventions," commented Dr Ramsey.

"Hominid diets have changed drastically through millions of years of evolution.,,,But only in the past 100 years has our diet drastically switched from a whole foods diet to one that is more processed and high in refined carbohydrates; that includes more vegetable fats rather than meat fats; and preservatives, emulsifiers, and other additives, which appear to have contributed to a decline in our collective health.

Early humans evolved in the African Rift Valley, which is near a seacoast. It's possible that whatever evolutionary spark occurred that made us human occurred here, in part due to reliable access to seafoodoysters in particular—which glutted our brains with omega-3 fatty acids and cholesterol (our brains are composed of 60% fat). Oysters and other mollusks are also very high in nutrients, including B12, which is commonly deficient in people consuming vegan or vegetarian diets and is necessary for myelin and neurotransmitter function. 

A number of studies have linked the Mediterranean diet (high in fish oils, nuts, and grains and including maybe a little red wine) with advantageous effects on neurologic and mental health. Dr Deans cited recent work reporting that adults who followed the Mediterranean dietary pattern the closest over 4.4 years had a significantly reduced risk of developing depression (40%-60%)....When taken together, most of these dietary pattern studies, which have been conducted all over the world, consistently show that traditional, pre-processed diets are the healthiest, including for the brain. ..."Eat the rainbow," he says, given that bold, bright colors in nature tend to signify valuable vitamins and phytonutrients (the reds, purples, and greens in particular).

Seafood: Seafood is packed with brain-healthy omega-3 fatty acids. These healthy fats are also abundant in plants like chia and flax, but plant-based sources aren't as efficiently converted to docosahexaenoic acid (DHA), an important structural component of neuronal membranes. DHA also influences the expression of brain-derived neurotrophic factor (BDNF), which can benefit people who have mood and anxiety disorders. Bivalves like mussels, oysters, and clams are the top source of vitamin B12 as well as zinc: Six oysters (only about 10 calories each) provide 240% of our recommended daily B12 intake and 500% of our recommended zinc intake! Seafood is also a leading dietary source of vitamin D (we don't get it all from the sun) as well as iodine and chromium. Although many people worry about mercury in fish, Dr Ramsey provided an easy way around the concern: Eat small fish like sardines, anchovies, and herring, which typically don't accumulate toxic levels.

Leafy greens: A great base for a brain-food diet, leafy greens are a good source of fiber, folate (derived from the wordfoliage), magnesium, and vitamin K. Perhaps surprising, kale, mustard greens, and bok choy provide the most absorbable form of calcium on the planet, more so than milk. Greens also provide flavanols and carotenoids that have beneficial epigenetic influences (eg, including upping hepatic toxin processing). 

Nuts:... Nuts are packed with healthy monounsaturated fats. They help keep us full and also aid in absorbing fat-soluble nutrients. Nuts also provide fiber as well as minerals like manganese and selenium. A serving of 22 almonds (just 162 calories) contains 33% of our recommended vitamin E, plenty of protein, and minerals, including iron. One study from 2013 found that the Mediterranean diet augmented with nuts is associated with significantly higher BDNF levels in patients with depression.

Legumes: Dr Ramsey is pro-meat, but he acknowledges that many people are eating far too much and the wrong types of meat, and that nuts and legumes are a great alternative source of protein and nutrients...Some data suggest that vegan and vegetarian diets are associated with improved mood. But as previously mentioned, these dietary patterns can result in B12 deficiency, which has been associated with brain atrophy and developmental delay. Hence, supplementation is important in this population. Vegetarianism has also been linked with depression, anxiety, and eating disorders, as well as increased healthcare utilization and worse quality of life. These negative associations also could be due to the fact that it's harder to absorb nutrients like zinc, iron, and certain omega-3s from plants.

"The notion that the vegan diet is the healthiest diet on the planet is probably incorrect," said Dr Ramsey, before explaining that he just feels that we should approach meat in our diets differently....We want to help patients use beef and seafood more as flavorings on top of a plant-based diet." A modest amount of meat in the diet has its benefits, including nutrient availability: Hemoglobin-derived iron is up to 40% more absorbable than plant-based iron. Unlike most plants, meat provides all of the amino acids necessary for protein synthesis. Dr Ramsey emphasized the importance of seeking out leaner, grass-fed meats if one has the means.

The understanding of how microbiota contribute to our mental and medical well-being is rapidly advancing....One of the most powerful interventions to alter our microbiome is diet. Research shows that stressed mice experienced changes in the gastrointestinal microbiota, reflecting the gut-brain relationship. There are 260 million neurons connecting the gut and the brain; furthermore, many commensal gut bacteria make neurotransmitters and communicate with the brain via the vagus nerve....Although the science of probiotic therapies is relatively young, it's clear that these commensal organisms co-evolved with us and are adapted to our diet.

Finally, to close out the session, Dr Ramsey returned to the stage and asked, "So, can you eat to build a better brain? We think that you can if you focus on dietary patterns and not a single food here or there." He also reminded the audience to help their patients identify and increase their consumption of nutrient-dense foods and to "eat the rainbow,"..."I don't know of anything else that can potentially decrease the risk of depression in a population by 40%," he concluded. "Perhaps diet is the closest we've come to prevention in psychiatry."

...Evidence suggests that curcumin, an ingredient in turmeric, increases BDNF. Other research has found that populations that eat more curry have a decreased risk for dementia, while rosemary extract may help prevent cognitive impairment. "Many spices seem to have healing properties," Dr Ramsey commented.

Although the "Food and the Brain" session at the American Psychiatric Association annual meeting focused on what to eat in the interest of brain health, intermittent fasting might also be beneficial for the brain. In addition to helping maintain a healthy weight, fasting induces ketosis. Ketone metabolism has been shown to be beneficial for the brain and improve cognition in patients with mild cognitive impairment or Alzheimer disease. Keep in mind that fasting can come with risks for some people, particularly diabetics, and should be discussed with a healthcare provider.

For years there has been discussion about curcumin's anti-inflammatory, anti-bacterial, and anti-cancer effects, but more research is needed (some trials are going on now). Curcumin is a chemical compound found in turmeric. Turmeric is a member of the ginger family. It is used as a spice and is a common ingredient in Indian cooking, but also used in Middle Eastern and South Asian recipes.From Medical Xpress;

Curcumin proved effective at combating cancer

WA scientists have helped re-affirm that curcumin, a chemical compound found in turmeric, is a safe and promising treatment for most cancers and other inflammation-driven diseases.The international review considered past clinical trials using curcumin to treat cancer patients and concluded curcumin was a safe and effective molecule to treat cancer.

A/Prof Sethi says curcumin is exceptionally effective for multiple myeloma patients and those suffering from the particularly lethal pancreatic cancer, for which there are no drugs. However, curcumin was not found to be as effective in breast cancer patients being treated with the chemotherapeutic agent cyclophosphamide. According to the research, curcumin can counteract the effect of cyclophosphamide.

A/Prof Sethi says curcumin is possibly the only drug that can be given at high doses—up to 12g—without any toxicity.... A/Prof Sethi says the only known side effect of the agent is blood thinning, and therefore advises against taking curcumin if undergoing surgery.

He recommends people use turmeric more often in everyday cooking. A/Prof Sethi says it would be ideal to combine curcumin with other drugs or natural compounds, like piperine, an alkaloid found in pepper to increase its bioavailabilty..

A/Prof Sethi says there is a lack of data to explain the underlying mechanism of its effect, however, it is known for its anti-inflammatory effects. "It has been shown that most chronic diseases, including cancer, are caused by inflammation and can be treated by anti-inflammatory agents."He says more work needs to be done to improve curcumin's viability, as body tissues quickly absorb it.