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Category: nutrition

Published on Leave a comment on Could Changing Your Diet Prevent Gout?

Gout is something that is not discussed that much, but it has been increasing in recent years and now afflicts about  3.9% of adults in the US. Gout is a form of inflammatory arthritis, characterized by recurrent attacks of pain, tenderness, and swelling of a joint, frequently the joint of the big toe. It is caused by elevated levels of uric acid in the blood (known as hyperuricaemia).

Gout occurs more commonly in men ages 40 and older, who eat a lot of meat and seafood, drink a lot of alcohol (especially beer) or sweetened drinks, have high blood pressure, metabolic syndrome, or are overweight.  Gout used to be known as "the disease of kings" or "rich man's disease". [On the other hand, past research has shown that consumption of coffee, cherries, vitamin C foods, and dairy products, losing weight and physical fitness seems to decrease the risk.]

Recent research showed that the DASH diet reduces blood pressure and reduces uric acid in the blood, which is why a research team (study in The BMJ) now looked at  whether it lowers the risk of gout. The Dietary Approaches to Stop Hypertension or DASH diet is high in fruit, vegetables, whole grains, legumes, nuts, and low-fat dairy, and low in red and processed meats, salt, and sugary drinks. On the other hand, the typical Western diet has higher intakes of red and processed meats, sweetened beverages, sweets, desserts, French fries, and refined grains. The researchers analysed data on a total of 44,444 male health professionals, who had no history of gout at the start of the study. During the 26 years of the observational study, they documented 1731 cases of gout.

The researchers found that eating a more DASH type diet - a diet rich in fruits, vegetables, legumes, nuts, whole grains, and low in salt, sugary drinks, and red and processed meats, is associated with a lower risk of gout. On the other hand, a more 'Western' diet is associated with a higher risk of gout. They found that the effects are dose dependent - the more DASH-type diet, the lower the risk of gout. Bottom line: Once again, eating lots of fruits, vegetables, nuts, legumes, and whole grains is linked to health benefits. From Science Daily:

Diet rich in fruit, vegetables and whole grains may lower risk of gout

A diet rich in fruit and vegetables, nuts and whole grains and low in salt, sugary drinks, and red and processed meats, is associated with a lower risk of gout, whereas a typical 'Western' diet is associated with a higher risk of gout, finds a study published by The BMJ.

Gout is a joint disease which causes extreme pain and swelling. It is most common in men aged 40 and older and is caused by excess uric acid in the blood (known as hyperuricaemia) which leads to uric acid crystals collecting around the joints. The Dietary Approaches to Stop Hypertension (DASH) diet reduces blood pressure and is recommended to prevent heart disease. It has also been found to lower uric acid levels in the blood. Therefore, the DASH diet may lower the risk of gout.

To investigate this further, a team of US and Canada based researchers examined the relationship between the DASH and Western dietary patterns and the risk of gout. They analysed data on over 44,000 men aged 40 to 75 years with no history of gout who completed detailed food questionnaires in 1986 that was updated every four years through to 2012.

Each participant was assigned a DASH score (reflecting high intake of fruits, vegetables, nuts and legumes, such as peas, beans and lentils, low-fat dairy products and whole grains, and low intake of salt, sweetened beverages, and red and processed meats) and a Western pattern score (reflecting higher intake of red and processed meats, French fries, refined grains, sweets and desserts). During 26 years of follow-up, a higher DASH score was associated with a lower risk for gout, while a higher Western pattern was associated with an increased risk for gout.

 Gout. Credit: NHS in the UK

Published on Leave a comment on Higher Arsenic Levels In Babies Who Eat Rice Cereal

The research finding of so many baby foods with elevated arsenic levels (above the legal limit) in the European Union made me wonder about arsenic standards in baby cereals in the US. It turns out that the US has "parallel" standards to the European Union. The EU has "maximum 0.1 milligrams of arsenic per kilogram of rice" (this standard has been in place since January 2016), and in  2016 the US the FDA proposed a "maximum allowed standard of 100 ppb (parts per billion)" in infant rice cereal.

Why is there so much arsenic in baby cereal? It's in the rice - rice plants absorb arsenic from the soil (it may be naturally occurring in the soil or in the soil because of arsenic pesticides that were used for years). And why should we be concerned about arsenic in food? The health effects of regularly consuming infant rice cereal — and other rice-based products —containing traces of arsenic are currently unclear. But...the researchers stated that early-life exposure to arsenic, even at low concentrations, is of particular concern because infants and young children are especially vulnerable to the adverse health effects of arsenic. Arsenic is a carcinogen (causes cancer), and can have "neurological, cardiovascular, respiratory and metabolic" effects.

A Harvard Health Publication (Harvard Medical School) publication in 2016 stated: "In high doses it is lethal, but even small amounts can damage the brain, nerves, blood vessels, or skin — and increase the risk of birth defects and cancer." The FDA found that inorganic arsenic exposure in infants and pregnant women can result in a child’s decreased performance on certain developmental tests that measure learning, based on epidemiological evidence including dietary exposures.

So what should parents do? The American Academy of Pediatricians (AAP) encourages that babies and toddlers eat a variety of foods, and that this will decrease a child's exposure to arsenic from rice. They also encourage other options as first foods (rather than just rice cereal), such as oat, barley, and multigrain cereals - all of which have lower arsenic levels than rice cereal. From Science Daily:

New research shows illegal levels of arsenic found in baby foods

In January 2016, the EU imposed a maximum limit of inorganic arsenic on manufacturers in a bid to mitigate associated health risks. Researchers at the Institute for Global Food Security at Queen's have found that little has changed since this law was passed and that 50 per cent of baby rice food products still contain an illegal level of inorganic arsenic. Professor Meharg, lead author of the study and Professor of Plant and Soil Sciences at Queen's, said: "....Babies are particularly vulnerable to the damaging effects of arsenic that can prevent the healthy development of a baby's growth, IQ and immune system to name but a few."

Rice has, typically, ten times more inorganic arsenic than other foods and chronic exposure can cause a range of health problems including developmental problems, heart disease, diabetes and nervous system damage. As babies are rapidly growing they are at a sensitive stage of development and are known to be more susceptible to the damaging effects of arsenic, which can inhibit their development and cause long-term health problems. Babies and young children under the age of five also eat around three times more food on a body weight basis than adults, which means that, relatively, they have three times greater exposures to inorganic arsenic from the same food item.

The research findings, published in the PLOS ONE journal today, compared the level of arsenic in urine samples among infants who were breast-fed or formula-fed before and after weaning. A higher concentration of arsenic was found in formula-fed infants, particularly among those who were fed non-dairy formulas which includes rice-fortified formulas favoured for infants with dietary requirements such as wheat or dairy intolerance. The weaning process further increased infants' exposure to arsenic, with babies five times more exposed to arsenic after the weaning process, highlighting the clear link between rice-based baby products and exposure to arsenic.

In this new study, researchers at Queen's also compared baby food products containing rice before and after the law was passed and discovered that higher levels of arsenic were in fact found in the products since the new regulations were implemented. Nearly 75 per cent of the rice-based products specifically marketed for infants and young children contained more than the standard level of arsenic stipulated by the EU law.[Original study.]

A 2016 study done in New Hampshire also showed that babies eating rice cereals and other rice-based snacks had higher amounts of arsenic in their urine compared to infants who did not eat rice foods. From JAMA Pediatrics: Association of Rice and Rice-Product Consumption With Arsenic Exposure Early in Life

Published on Leave a comment on Should We Be Worried That Humans Are Losing Many Species of Gut Microbes?

An article was just published in a research journal to discuss the fact that humans - in part due to lifestyles which include less dietary fiber (due to eating fewer varieties and amounts of plants) and due to medical practices (such as frequent use of antibiotics) has resulted in gut "bacterial extinctions". In other words, humans (especially those living an urban industrialized Western lifestyle) have fewer gut bacterial species than those living a more traditional lifestyle, and this loss of bacterial species is linked to various diseases. Humans can increase the number of certain bacterial species, but the loss of some bacterial species is forever. 

The researchers discuss that humans have the "lowest level of gut bacterial diversity"  of any hominid and primate. They stated that the shrinking of the variety of microbial species in the human gut (the gut microbiome) began early in human evolution (as humans started eating more meat), but that it has accelerated dramatically within industrialized societies. And that evidence is accumulating that this gut bacterial "depauperation" - the loss of a variety of bacterial species - may predispose humans to a range of diseases.  Some of it is due to evolution (as humans ate more meat), and some to lifestyle changes. A term is used throughout this paper: depauperate - which means lacking in numbers or variety of species in the gut microbiome (the microbial community or ecosystem).

Other research has also shown that eating a highly processed Western diet results in gut microbial changes that are linked to various diseases (here, here, here) - that is, the microbes being fed are those associated with diseases. Also, certain diets encourage certain microbial species to flourish (here, here).  Bottom line: studies find health benefits from higher levels of dietary fiber - from fruits, vegetables, seeds, nuts, whole grains, and legumes (beans). From Current Opinion In Microbiology:

The shrinking human gut microbiome

Highlights: Humans harbor the lowest levels of gut bacterial diversity of any hominid. Humans in industrialized nations harbor fewer gut bacterial taxa than any primate. Medical practices and lack of dietary fiber may drive gut bacterial extinctions. Depauperate microbiotas may predispose entire human populations to certain diseases.

Mammals harbor complex assemblages of gut bacteria that are deeply integrated with their hosts’ digestive, immune, and neuroendocrine systems. Recent work has revealed that there has been a substantial loss of gut bacterial diversity from humans since the divergence of humans and chimpanzees. This bacterial depauperation began in humanity’s ancient evolutionary past and has accelerated in recent years with the advent of modern lifestyles. Today, humans living in industrialized societies harbor the lowest levels of gut bacterial diversity of any primate for which metagenomic data are available, a condition that may increase risk of infections, autoimmune disorders, and metabolic syndrome. Some missing gut bacteria may remain within under-sampled human populations, whereas others may be globally extinct and unrecoverable.

A typical human harbors on the order of 1013 bacterial cells in the large intestine. This gut microbiota, which can contain over a thousand species, is deeply integrated with virtually every tissue and organ system in the body. Gut bacteria process difficult to digest components of the diet, promote angiogenesis in the intestine, train the immune system, regulate metabolism, and even influence moods and behaviors.

In contrast to hunter–gatherer to agricultural transitions, adoptions of industrial and post-industrial lifestyles have led to massive reductions in bacterial richness within human gut microbiotas. Individuals living in urban centers in the United States harbor fewer gut bacterial species on average than do individuals living more traditional lifestyles in Malawi , Venezuela, Peru, and Papua New Guinea.....Industrialized and traditional lifestyles differ in many respects, confounding the identification of the specific practices that have led to decreases in gut bacterial diversity within industrialized societies. One potential cause is the rise of food processing and the corresponding reductions in the intake of dietary fiber in favor of simple sugars. Recently, studies in model systems have indicated that long-term reductions in dietary fiber can lead to the extirpation of gut bacterial taxa from host lineages. 

Other potential causes of reduced gut bacterial diversity within industrialized human populations include certain modern medical practices. For example, longitudinal studies in humans have shown that levels of gut bacterial diversity decrease drastically after antibiotic use. Although bacterial richness may recover after treatment is completed, the timeline and extent of the restoration is highly subject-dependent. The consequences of antibiotic use on gut bacterial diversity may be most severe when treatment is administered during the early years of life, before the adult microbiota has fully formed .

Published on Leave a comment on Blood Pressure Study Contradicts Sodium Limits in Dietary Guidelines

Another large recent study found that lowering sodium intakes (less than 2500 milligrams per day) wasn't linked to lower blood pressure. Over the course of 16 years, the researchers found that the study participants who consumed less than 2500 milligrams of sodium a day had higher blood pressure than participants who consumed higher amounts of sodium. However, the current 2015-2020 Dietary Guidelines for Americans recommends limiting sodium intake to 2,300 grams a day for healthy people. The researchers felt that based on recent studies with similar findings that the sodium guidelines should be changed.

This 16 year study found that people in the study who had normal intakes of sodium, but also higher intakes of potassium, calcium and magnesium exhibited lower blood pressure over the course of the study. And those people with higher combined intakes of sodium (3717 milligrams per day on average) and potassium (3211 milligrams per day on average on average) had the lowest blood pressure.

Some good potassium foods:  avocado, winter squash, sweet potato, potato, white beans, banana, spinach, salmon, dried apricots, tomato sauce, beans, and milk. Some good magnesium foods: dark leafy greens, nuts, seeds, fish, beans, whole grains, avocados, yogurt, bananas, dried fruit, dark chocolate. Some good calcium foods: milk, cheese, yogurt, kale, sardines, broccoli, white beans, and rhubarb. From Science Daily:

Low-sodium diet might not lower blood pressure: Findings from large, 16-year study contradict sodium limits in Dietary Guidelines for Americans

A new study that followed more than 2,600 men and women for 16 years found that consuming less sodium wasn't associated with lower blood pressure. The new findings call into question the sodium limits recommended by the current Dietary Guidelines for Americans. Lynn L. Moore, DSc, associate professor of medicine at Boston University School of Medicine, will present the new research at the American Society for Nutrition Scientific Sessions and annual meeting during the Experimental Biology 2017 meeting, to be held April 22-26 in Chicago.

"We saw no evidence that a diet lower in sodium had any long-term beneficial effects on blood pressure," said Moore. "Our findings add to growing evidence that current recommendations for sodium intake may be misguided." The 2015-2020 Dietary Guidelines for Americans recommends limiting sodium intake to 2,300 grams a day for healthy people. For the study, the researchers followed 2,632 men and women ages 30 to 64 years old who were part of the Framingham Offspring Study. The participants had normal blood pressure at the study's start. However, over the next 16 years, the researchers found that the study participants who consumed less than 2500 milligrams of sodium a day had higher blood pressure than participants who consumed higher amounts of sodium.

Other large studies published in the past few years have found what researchers call a J-shaped relationship between sodium and cardiovascular risk -- that means people with low-sodium diets (as recommended by the Dietary Guidelines for Americans) and people with a very high sodium intake (above the usual intake of the average American) had higher risks of heart disease. Those with the lowest risk had sodium intakes in the middle, which is the range consumed by most Americans.

The researchers also found that people in the study who had higher intakes of potassium, calcium and magnesium exhibited lower blood pressure over the long term. In Framingham, people with higher combined intakes of sodium (3717 milligrams per day on average) and potassium (3211 milligrams per day on average on average) had the lowest blood pressure.....Moore says that there is likely a subset of people sensitive to salt who would benefit from lowering sodium intake, but more research is needed to develop easier methods to screen for salt sensitivity and to determine appropriate guidelines for intakes of sodium and potassium in this salt-sensitive group of people.

Published on Leave a comment on Canadian Agency Detected Weed-Killer In 30 Percent of Foods Tested

This site has several recent posts about the controversial pesticide glyphosate (found in Monsanto's Round-Up). Glyphosate is the most heavily used pesticide in the world, and is used as a weed-killer (herbicide). It is used extensively in the USA - on farms, on roadsides, on residential properties, on school properties - basically everywhere, and its use is increasing. Studies have reported to have a number of worrisome health effects (including cancer) which its manufacturer is vigorously denying. There have even been recently revealed ties between Monsanto and some officials in the EPA.

United States government agencies only looked for the presence of glyphosate residues in some foods for a short time last year, and then stopped all testing. So WE DON'T KNOW HOW MUCH GLYPHOSATE WE ARE INGESTING DAILY in the United States. Our government refuses to test. Journalist Carey Gillam wrote that "a source within the FDA said there has been political pressure not to delve too deeply into the issue of glyphosate residues". To many it smacks of: if we don't test for glyphosate in foods, then there is no problem of how much is in foods. Because everyone agrees it is found in food - that's why there are standards for maximum residue levels or "tolerances" (but note they were increased when Monsanto asked to have them increased).

Well.....Canada does test for the pesticide in foods. The Canadian Food Inspection Agency just released a report of the results of testing 3,188 foods for traces of glyphosate residues, and found the pesticide in nearly 30% of the foods tested. Residue levels were above the Canadian acceptable limits in 1.3% of the foods. Glyphosate was found the most in: beans, peas, and lentil products (47.4%); grain products (36.6%); and baby cereals (31%). Only 1.3 percent of the total samples were found with glyphosate residue levels above what Canadian regulators allow, though 3.9 percent of grain products contained more of the weed killer than is permissible.

Legally allowable levels or Maximum Residue Levels (MRLs) vary from food to food and pesticide to pesticide, as well as from country to country. The European Union allowable residues for glyphosate on foods are lower than the US maximum allowable amount (yes, once again American standards are more lax). And remember that people ingest numerous pesticides in their foods, and no one knows what health effects are from these combinations of chronic low level pesticide exposures. NOTE: The only way to avoid glyphosate residues in foods is to eat organic foods. Glyphosate is not allowed to be used on organic foods or in organic feed for organically raised animals.

Canadian Food Inspection Agency: Safeguarding with Science: Glyphosate Testing in 2015-2016

Published on Leave a comment on Eating Fresh Fruit Is Linked to Lower Risk of Diabetes and Diabetic Complications

 Good news! Once again a study has confirmed that eating fresh fruits is associated with a lower incidence of type 2 diabetes. And even better - there is a dose related relationship - the more one eats daily, the better. So don't worry about the "sugar content" of fruit - the key is to eat fruit (as well as vegetables) to lower the risk of getting diabetes. And if you have type 2 diabetes, it will lower the incidence of death and complications from diabetes.

Here are the numbers for the 7 year study done in China of almost half a million people: eating fresh fruit was associated with a 12% lower risk of developing diabetes (compared to those never or rarely consuming fresh fruit). And in those who already had diabetes at the start of the study, consuming fresh fruit more than three days a week was associated with a 17% lower relative risk of dying from any cause and a 13%–28% lower risk of developing diabetes-related complications than those who consumed fruit less than one day per week.

Yes, I remember the advice that used to be given and is still given in parts of the world - that if you have diabetes, to restrict fruit, but studies are showing that advice to be wrong. Note that eating fresh fruits and vegetables has lots of other health benefits also - including lower rates of heart disease, stroke, and better mental (cognitive) functioning. From Science Daily:

Fresh fruit consumption linked to lower risk of diabetes and diabetic complications

In a research article published in PLOS Medicine, Huaidong Du of the University of Oxford, Oxford, United Kingdom and colleagues report that greater consumption of fresh fruit was associated with a lower incidence of diabetes, as well as reduced occurrence of complications in people with diabetes, in a Chinese population.

Although the health benefits of diets including fresh fruit and vegetables are well established, the sugar content of fruit has led to uncertainty about associated risks of diabetes and of vascular complications of the disease. Du and colleagues studied nearly 500,000 people participating in the China Kadoorie Biobank over about 7 years of follow-up, documenting new cases of diabetes and recording the occurrence of vascular disease and death in people with pre-existing diabetes.

The researchers found that people who reported elevated consumption of fresh fruit had a lower associated risk of developing diabetes in comparison with other participants (adjusted hazard ratio [aHR] 0.88, 95% CI 0.83-0.93), which corresponds to an estimated 0.2% reduction in the absolute risk of diabetes over 5 years. In people with diabetes, higher consumption of fresh fruit was associated with a lower risk of mortality (aHR 0.83, 95% CI 0.74-0.93 per 100g fruit/d), corresponding to an absolute decrease in risk of 1.9% at 5 years, and with lower risks of microvascular and macrovascular complications. [Original study.]

Published on Leave a comment on Foods High In Potassium Linked to Lower Blood Pressure

Nothing new here, but good to have it discussed again: eating foods high in potassium and low in sodium (salt) lowers blood pressure. Why should we care? Hypertension (high blood pressure) is a global health issue. The World Health Organization estimates that hypertension is responsible for at least 51 percent of deaths due to stroke and 45 percent of deaths due to heart disease.

Eating the potassium rich foods seems to be key. Some foods high in potassium: bananas, baked potatoes, sweet potatoes, dark leafy greens (e.g., spinach, kale), tomatoes, mushrooms, beans (e.g., white beans, pinto beans), lentils, nuts, broccoli, apricots, milk. In other words, eat an assortment of fruits, vegetables, beans, and nuts to get potassium. And coincidentally these same foods are low in sodium (salt) - a win-win for heath. From Science Daily:

Fruits and vegetables' latest superpower? Lowering blood pressure

Eating potassium-rich foods like sweet potatoes, avocados, spinach, beans, bananas -- and even coffee -- could be key to lowering blood pressure, according to Alicia McDonough, PhD, professor of cell and neurobiology at the Keck School of Medicine of the University of Southern California (USC). "Decreasing sodium intake is a well-established way to lower blood pressure," McDonough says, "but evidence suggests that increasing dietary potassium may have an equally important effect on hypertension."

McDonough explored the link between blood pressure and dietary sodium, potassium and the sodium-potassium ratio in a review article....McDonough's review found several population studies demonstrating that higher dietary potassium (estimated from urinary excretion or dietary recall) was associated with lower blood pressure, regardless of sodium intake. Interventional studies with potassium supplementation also suggested that potassium provides a direct benefit.

McDonough reviewed recent studies in rodent models, from her own lab and others, to illustrate the mechanisms for potassium benefit. These studies indicated that the body does a balancing act that uses sodium to maintain close control of potassium levels in the blood, which is critical to normal heart, nerve and muscle function. "When dietary potassium is high, kidneys excrete more salt and water, which increases potassium excretion," McDonough says. "Eating a high potassium diet is like taking a diuretic." "If you eat a typical Western diet," McDonough says, "your sodium intake is high and your potassium intake is low. This significantly increases your chances of developing high blood pressure." 

But how much dietary potassium should we consume? A 2004 Institute of Medicine report recommends that adults consume at least 4.7 grams of potassium per day to lower blood pressure, blunt the effects of dietary sodium and reduce the risks of kidney stones and bone loss, McDonough says. Eating ¾ cup of black beans, for example, will help you achieve almost 50 percent of your daily potassium goal. [Original study.]

Published on Leave a comment on High Dose Vitamin D Does Not Prevent Cardiovascular Disease

A recent study looking at high dose supplementation of vitamin D found that it did not prevent cardiovascular disease. This study came about because of earlier studies observing that there is a higher incidence of cardiovascular disease in persons with low vitamin D levels (as measured in their blood). But such results from observational studies need rigorous testing in studies where people are randomly assigned to groups, and that are "double-blind" (no one knows who is getting the vitamin D until the end of the study) to eliminate bias. And this is what was done in this study, with the result that monthly high doses of vitamin D3 for 3 years did not prevent cardiovascular disease (including stroke, heart attacks, hypertension, etc) - as seen in that there were no group differences between the vitamin D and placebo groups. Finding no effects are "null findings".

But note that the subjects in the study got monthly high doses, and not daily or weekly vitamin D. It is unknown whether daily dosing would have made a difference in the results. However, the vitamin D levels in the blood soon reached levels (about 51.725 ng/mL) that many view as a desirable "protective" level. So we'll see what other studies find. But these results are definitely disappointing for those wanting an easy "magic bullet" for preventing cardiovascular disease. Bottom line: focus on lifestyle (diet, exercise, not smoking, etc) for heart health. From Science Daily:

Monthly high-dose vitamin D supplementation does not prevent cardiovascular disease

Results of a large randomized trial indicate that monthly high-dose vitamin D supplementation does not prevent cardiovascular disease, according to a study published by JAMA Cardiology. Studies have reported increased incidence of cardiovascular disease (CVD) among individuals with low vitamin D status. To date, randomized clinical trials of vitamin D supplementation have not found an effect, possibly because of using too low a dose of vitamin D. Robert Scragg, M.B.B.S., Ph.D., of the University of Auckland, New Zealand, and colleagues randomly assigned adults (age 50 to 84 years) to receive oral vitamin D3 (n = 2,558; an initial dose of 200,000 IU, followed a month later by monthly doses of 100,000 IU) or placebo (n = 2,552) for a median of 3.3 years.

Of the 5,108 participants included in the primary analysis, the average age was 66 years; 25 percent were vitamin D deficient. Cardiovascular disease occurred in 303 participants (11.8 percent) in the vitamin D group and 293 participants (11.5 percent) in the placebo group. Similar results were seen for participants with vitamin D deficiency at study entry and for other outcomes such as heart attack, angina, heart failure, hypertension, and stroke.

The authors write that the results of this study do not support the use of monthly high-dose vitamin D for the prevention of CVD. "The effects of daily or weekly dosing on CVD risk require further study." [Original study.]

Published on Leave a comment on Eat Lots of Fiber For Gut Health

 Nice research that basically says: food is medicine. In other words, eat lots of whole grains and legumes (beans) for gut health - to feed the beneficial microbes in your gut and prevent (hopefully) colon cancer. While the clinical trial studied colorectal cancer survivors and the effects of 4 weeks of adding rice bran or navy beans or placebo (nothing extra) daily to their diet - the positive effects of adding the extra dietary fiber included increased microbiome richness and diversity in the rice bran group (which is good).

And when researchers treated colorectal cancer cells with stool extracts from these groups, they saw reduced cell growth from the groups that had increased rice bran and navy bean consumption. This was an important finding and stresses that adding fiber to the diet is beneficial to gut health, and perhaps may prevent colorectal cancer.

Other studies have also found a diet with lots of legumes (beans), whole grains, vegetables, fruits, nuts, and seeds to be beneficial for gut microbes and gut health. A classic study (from 2015) found dramatic changes in the colon (specifically in the colonic mucosa) from dietary changes in as little as 2 weeks. They compared the typical low-fat, high fiber diet of South Africa with an “American” high-fat, low-fiber diet, and found that after two weeks on the high fiber African diet, there was significantly less inflammation in the colon and reduced biomarkers of cancer risk. On the other hand, measurements indicating cancer risk dramatically increased after two weeks on the western diet. That study found that a major reason for the changes in cancer risk was the way in which the bacteria in the gut (the microbiome) were altered in adapting to the new diet. The researchers suggested trying for at least 50 grams of fiber per day for gut health benefits.

From Medical Xpress: Phase II trial: Rice bran adds microbiome diversity, slows growth of colon cancer cells

Today at the American Association for Cancer Research (AACR) Annual Meeting 2017, University of Colorado Cancer Center researchers at Colorado State University present results of a phase II clinical trial of 29 people exploring the effects of adding rice bran or navy beans to the diets of colorectal cancer survivors. After the 4-week randomized-controlled trial during which people added rice bran, navy bean powder or neither, both the rice bran and navy bean groups showed increased dietary fiber, iron, zinc, thiamin, niacin, vitamin B6, folate, and alpha-tocopherol. The rice bran group also showed increased microbiome richness and diversity. When researchers treated colorectal cancer cells with stool extracts from these groups, they saw reduced cell growth from the groups that had increased rice bran and navy bean consumption.

Previous work shows the ability of these diets to decrease colorectal cancer risk in animal models. The current trial confirms that people can eat enough bean- and rice bran-enhanced foods to promote gut health at levels shown to prevent colorectal cancer in animals. Guidelines from the American Institute for Cancer Research recommend reducing the risk of cancer by eating more vegetables, fruits, whole grains and legumes, such as beans. Ryan has established from these studies that eating a half-cup of beans and 30 grams of rice bran per day is enough to see changes in small molecules that can confer protection against colorectal cancer.

"The simple message is, 'Food is medicine,' and we are looking at how to simplify that and make it apply to our everyday lives," says study co-author Regina Brown, MD, assistant professor at the CU School of Medicine and oncologist for CUHealth...."The evidence is there in animals and we can now study this in people. The question is, what are we doing to achieve adequate levels of intake of these foods?" Ryan said. "It's not enough to say 'I eat them once in a while.' That's not going to work, particularly if you are at higher risk. You have to meet a dose, just like you need a dose of a certain drug, you need to reach intake levels and consume increased amounts of these foods, and that's where people, including me, are challenged. Not everyone wants to open up a can of beans and eat them every day."

Published on Leave a comment on Does Vitamin D Prevent Cancer?

Does vitamin D prevent cancer? There has been much debate over whether increasing levels of vitamin D (as measured in a person's blood) results in a lower incidence of cancer. Studies find a number of health problems linked to low levels of vitamin D (here, here, here), while studies looking at vitamin D and cancer have been "inconsistent" in their results. Some say yes - vitamin D is protective, while some say there is no effect from vitamin D supplements. Now a 4 year study (yes, yes - it's a very short length of time in which to study the onset of cancer) found no difference in the rate of cancer among two groups of postmenopausal women who received either: 2,000 IU per day of vitamin D3 and 1,500 mg per day of calcium OR an identical looking placebo. They looked for any kind of cancer occurring.

The Creighton University researchers found a difference among the women after 4 years, with the vitamin D plus calcium supplement group having fewer cancers (and a lower percentage of cancer) as compared to the placebo group, but...it did not reach statistical significance. So you could say it was due to chance. But when the researchers looked at the number of cancers from year 2 to 4, then the difference was statistically significant - that vitamin D was protective. The researchers wonder if the cancers diagnosed in year 1 were already developing before the study started. Note: The 2,000 IU per day vitamin D3 supplements in this study are considered high doses - "high dose supplementation".

The researchers point out that the women who were given vitamin D3 and calcium supplements had a 30% lower risk of cancer, even though this difference in cancer incidence rates between the 2 groups did not quite reach statistical significance. But both groups started with a fairly high vitamin D level -  an average 25-hydroxyvitamin D (25[OH]D) levels of 32.8 ng/m (which is above the average US population level). And in the supplement group it was raised to 43.9 ng/mL. Note that some researchers view vitamin D levels of 33 ng/mL  (the baseline level in both groups) as already protective against cancer.

Also, even during the study the placebo group was allowed to take their own vitamin D and calcium supplements as long as it wasn't more than the recommended amounts (800 IU per day for vitamin D and 1500 mg per day for calcium) - which makes those individuals actually a low vitamin D supplementation group rather than no supplementation, which might hide any treatment effects and so make the results for the 2 groups look similar. What is needed is a much longer follow-up, larger groups of women, and both high and low dose vitamin D supplement groups. Some studies suggest that whether a low or high dose taken has an effect on cancer incidence.

I still think this study period was way too short - to me, 5 or more years would have been more convincing, and the groups too small. Also, it was unfortunate that they were also given calcium supplements or that there wasn't a just vitamin D group. Combining vitamin D with calcium supplements just muddies the results (in my opinion), and also because calcium supplements are linked to health problems such as cardiovascular disease. So in this study can't tell what the separate effects of calcium and vitamin D are. (Note that calcium rich foods, however, are beneficial to health.)

But a big positive of the study was that the women were randomly assigned to either the vitamin D plus calcium group or the placebo group, and no one - not the women or their doctors knew who got what until the end of the study (to eliminate bias it was "double-blind"). Note The supplements used were vitamin D3 and not D2. Vitamin D can also be easily obtained by exposure to sunlight in the summer months.

Excerpts from Creighton University release about the study in Science Daily: Does Vitamin D decrease risk of cancer?

The study, funded by the National Institutes of Health, is a randomized clinical trial of the effects of vitamin D supplementation on all types of cancer combined. The four-year study included 2,303 healthy postmenopausal women 55 years and older from 31 counties in Nebraska. Participants were randomly assigned to take either 2000 international units (IU) of vitamin D3 and 1500 mg. of calcium or identical placebos daily for 4 years. The vitamin D3 dose was about three times the US government's Recommended Dietary Allowance (RDA) of 600 IU for adults through age 70, and 800 IU for those 71 and older. Women who were given vitamin D3 and calcium supplements had 30% lower risk of cancer. This difference in cancer incidence rates between groups did not quite reach statistical significance. However, in further analyses, blood levels of vitamin D, specifically 25-hydroxyvitamin D (25(OH)D), were significantly lower in women who developed cancer during the study than in those who remained healthy.

Original study in JAMA: Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women. Accompanying editorial about the study in JAMA:  Vitamin D, Calcium, and Cancer: Approaching Daylight?