Treating Kidney Stones with Diet

Treating Kidney Stones with Diet.jpeg

Studies suggest that excessive consumption of animal protein poses a risk of kidney stone formation, likely due to the acid load contributed by the high content of sulfur-containing amino acids in animal protein, a topic I explore in my video, Preventing Kidney Stones with Diet. What about treating kidney stones, though? I discuss that in How to Treat Kidney Stones with Diet. Most stones are calcium oxalate, formed like rock candy when the urine becomes supersaturated. Doctors just assumed that if stones are made out of calcium, we simply have to tell people to reduce their calcium intake. That was the dietary gospel for kidney stone sufferers until a 2002 study published in the New England Journal of Medicine pitted two diets against one another--a low-calcium diet versus a diet low in animal protein and salt. The restriction of animal protein and salt provided greater protection, cutting the risk of having another kidney stone within five years in half.

What about cutting down on oxalates, which are concentrated in certain vegetables? A recent study found there was no increased risk of stone formation with higher vegetable intake. In fact, greater dietary intake of whole plant foods, fruits, and vegetables were each associated with reduced risk independent of other known risk factors for kidney stones. This means we may get additional benefits bulking up on plant foods in addition to just restricting animal foods.

A reduction in animal protein not only reduces the production of acids within the body, but should also limit the excretion of urate, uric acid crystals that can act as seeds to form calcium stones or create entire stones themselves. (Uric acid stones are the second most common kidney stones after calcium.)

There are two ways to reduce uric acid levels in the urine: a reduction of animal protein ingestion, or a variety of drugs. Removing all meat--that is, switching from the standard Western diet to a vegetarian diet--can remove 93% of uric acid crystallization risk within days.

To minimize uric acid crystallization, the goal is to get our urine pH up to ideally as high as 6.8. A number of alkalinizing chemicals have been developed for just this purpose, but we can naturally alkalize our urine up to the recommended 6.8 using purely dietary means. Namely, by removing all meat, someone eating the standard Western diet can go from a pH of 5.95 to the goal target of 6.8--simply by eating plant-based. As I describe in my video, Testing Your Diet with Pee & Purple Cabbage, we can inexpensively test our own diets with a little bathroom chemistry, for not all plant foods are alkalinizing and not all animal foods are equally acidifying.

A Load of Acid to Kidney Evaluation (LAKE) score has been developed to take into account both the acid load of foods and their typical serving sizes. It can be used to help people modify their diet for the prevention of both uric acid and calcium kidney stones, as well as other diseases. What did researchers find? The single most acid-producing food is fish, like tuna. Then, in descending order, are pork, then poultry, cheese (though milk and other dairy are much less acidifying), and beef followed by eggs. (Eggs are actually more acidic than beef, but people tend to eat fewer eggs in one sitting.) Some grains, like bread and rice, can be a little acid-forming, but pasta is not. Beans are significantly alkaline-forming, but not as much as fruits or even better, vegetables, which are the most alkaline-forming of all.

Through dietary changes alone, we may be able to dissolve uric acid stones completely and cure patients without drugs or surgery.

To summarize, the most important things we can do diet-wise is to drink 10 to 12 cups of water a day, reduce animal protein, reduce salt, and eat more vegetables and more vegetarian.

Want to try to calculate their LAKE score for the day? Just multiply the number of servings you have of each of the food groups listed in the graph in the video times the score.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank

Original Link

Treating Kidney Stones with Diet

Treating Kidney Stones with Diet.jpeg

Studies suggest that excessive consumption of animal protein poses a risk of kidney stone formation, likely due to the acid load contributed by the high content of sulfur-containing amino acids in animal protein, a topic I explore in my video, Preventing Kidney Stones with Diet. What about treating kidney stones, though? I discuss that in How to Treat Kidney Stones with Diet. Most stones are calcium oxalate, formed like rock candy when the urine becomes supersaturated. Doctors just assumed that if stones are made out of calcium, we simply have to tell people to reduce their calcium intake. That was the dietary gospel for kidney stone sufferers until a 2002 study published in the New England Journal of Medicine pitted two diets against one another--a low-calcium diet versus a diet low in animal protein and salt. The restriction of animal protein and salt provided greater protection, cutting the risk of having another kidney stone within five years in half.

What about cutting down on oxalates, which are concentrated in certain vegetables? A recent study found there was no increased risk of stone formation with higher vegetable intake. In fact, greater dietary intake of whole plant foods, fruits, and vegetables were each associated with reduced risk independent of other known risk factors for kidney stones. This means we may get additional benefits bulking up on plant foods in addition to just restricting animal foods.

A reduction in animal protein not only reduces the production of acids within the body, but should also limit the excretion of urate, uric acid crystals that can act as seeds to form calcium stones or create entire stones themselves. (Uric acid stones are the second most common kidney stones after calcium.)

There are two ways to reduce uric acid levels in the urine: a reduction of animal protein ingestion, or a variety of drugs. Removing all meat--that is, switching from the standard Western diet to a vegetarian diet--can remove 93% of uric acid crystallization risk within days.

To minimize uric acid crystallization, the goal is to get our urine pH up to ideally as high as 6.8. A number of alkalinizing chemicals have been developed for just this purpose, but we can naturally alkalize our urine up to the recommended 6.8 using purely dietary means. Namely, by removing all meat, someone eating the standard Western diet can go from a pH of 5.95 to the goal target of 6.8--simply by eating plant-based. As I describe in my video, Testing Your Diet with Pee & Purple Cabbage, we can inexpensively test our own diets with a little bathroom chemistry, for not all plant foods are alkalinizing and not all animal foods are equally acidifying.

A Load of Acid to Kidney Evaluation (LAKE) score has been developed to take into account both the acid load of foods and their typical serving sizes. It can be used to help people modify their diet for the prevention of both uric acid and calcium kidney stones, as well as other diseases. What did researchers find? The single most acid-producing food is fish, like tuna. Then, in descending order, are pork, then poultry, cheese (though milk and other dairy are much less acidifying), and beef followed by eggs. (Eggs are actually more acidic than beef, but people tend to eat fewer eggs in one sitting.) Some grains, like bread and rice, can be a little acid-forming, but pasta is not. Beans are significantly alkaline-forming, but not as much as fruits or even better, vegetables, which are the most alkaline-forming of all.

Through dietary changes alone, we may be able to dissolve uric acid stones completely and cure patients without drugs or surgery.

To summarize, the most important things we can do diet-wise is to drink 10 to 12 cups of water a day, reduce animal protein, reduce salt, and eat more vegetables and more vegetarian.

Want to try to calculate their LAKE score for the day? Just multiply the number of servings you have of each of the food groups listed in the graph in the video times the score.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank

Original Link

How Much Water Should We Drink Every Day?

How Much Water Should We Drink Every Day?.jpeg

More than 2000 years ago Hippocrates (460-377 BCE) said, "If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health." What does that mean when it comes to water? Water has been described as a neglected, unappreciated, and under-researched subject, and further complicating the issue, a lot of the papers extolling the need for proper hydration are funded by the bottled water industry.

It turns out the often quoted "drink at least eight glasses of water a day" dictum has little underpinning scientific evidence . Where did that idea come from? The recommendation was traced to a 1921 paper, in which the author measured his own pee and sweat and determined we lose about 3% of our body weight in water a day, or about 8 cups (see How Many Glasses of Water Should We Drink in a Day?). Consequently, for the longest time, water requirement guidelines for humanity were based on just one person.

There is evidence that not drinking enough may be associated with falls and fractures, heat stroke, heart disease, lung disorders, kidney disease, kidney stones, bladder and colon cancer, urinary tract infections, constipation, dry mouth, cavities, decreased immune function and cataract formation. The problem with many of these studies is that low water intake is associated with several unhealthy behaviors, such as low fruit and vegetable intake, more fast-food, less shopping at farmers markets. And who drinks lots of water? People who exercise a lot. No wonder they tend to have lower disease rates!

Only large and expensive randomized trials could settle these questions definitively. Given that water cannot be patented, such trials seem unlikely; who's going to pay for them? We're left with studies that find an association between disease and low water intake. But are people sick because they drink less, or are they drinking less because they're sick? There have been a few large prospective studies in which fluid intake is measured before disease develops. For example, a Harvard study of 48,000 men found that the risk of bladder cancer decreased by 7% for every extra daily cup of fluid we drink. Therefore, a high intake of water--like 8 cups a day--may reduce the risk of bladder cancer by about 50%, potentially saving thousands of lives.

The accompanying editorial commented that strategies to prevent the most prevalent cancers in the West are remarkably straightforward in principle. To prevent lung cancer, quit smoking; to prevent breast cancer, maintain your ideal body weight and exercise; and to prevent skin cancer, stay out of the sun. Now comes this seemingly simple way to reduce the risk of bladder cancer: drink more fluids.

Probably the best evidence we have for a cut off of water intake comes from the Adventist Health Study, in which 20,000 men and women were studied. About one-half were vegetarian, so they were also getting extra water by eating more fruits and vegetables. Those drinking 5 or more glasses of water a day had about half the risk of dying from heart disease compared to those who drank 2 or fewer glasses a day. Like the Harvard study, this protection was found after controlling for other factors such as diet and exercise. These data suggest that it was the water itself that was decreasing risk, perhaps by lowering blood viscosity (blood thickness).

Based on all the best evidence to date, authorities from Europe, the U.S. Institute of Medicine, and the World Health Organization recommend between 2.0 and 2.7 liters (8 to 11 cups) of water a day for women, and 2.5 to 3.7 liters (10 to 15 cups) a day for men. This includes water from all sources, not just beverages. We get about a liter from food and the water our body makes. So this translates into a recommendation for women to drink 4 to 7 cups of water a day and men 6 to 11 cups, assuming only moderate physical activity at moderate ambient temperatures.

We can also get water from all the other drinks we consume, including caffeinated drinks, with the exception of stronger alcoholic drinks like wines and spirits. Beer can leave you with more water than you started with, but wine actively dehydrates you. However, in the cancer and heart disease studies I mentioned above, the benefits were only found with increased water consumption, not other beverages.

I've previously touched on the cognitive benefits of proper hydration here: Does a Drink Of Water Make Children Smarter?

Surprised tea is hydrating? See my video Is Caffeinated Tea Dehydrating?

Surprised that the 8-a-day rested on such flimsy evidence? Unfortunately, so much of what we do in medicine has shaky underpinnings. That's the impetus behind the idea of evidence-based medicine (what a concept!). Ironically, this new movement may itself undermine some of the most effective treatments. See Evidence-Based Medicine or Evidence-Biased?

How else can we reduce our risk of bladder cancer? See Raw Broccoli and Bladder Cancer Survival.

What kind of water? I recommend tap water, which tends to be preferable from a chemical and microbial contamination standpoint. What about buying one of those fancy alkalizing machines? See Alkaline Water: a Scam?

It's so nice to have data on such a fundamental question. We have much to thank the Adventists for. You will see their studies cropping up frequently. See, for example, Plant-Based Diets and Diabetes, The Okinawa Diet: Living to 100, and Evidence-Based Eating.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. Image has been modified.

Original Link

How Much Water Should We Drink Every Day?

How Much Water Should We Drink Every Day?.jpeg

More than 2000 years ago Hippocrates (460-377 BCE) said, "If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health." What does that mean when it comes to water? Water has been described as a neglected, unappreciated, and under-researched subject, and further complicating the issue, a lot of the papers extolling the need for proper hydration are funded by the bottled water industry.

It turns out the often quoted "drink at least eight glasses of water a day" dictum has little underpinning scientific evidence . Where did that idea come from? The recommendation was traced to a 1921 paper, in which the author measured his own pee and sweat and determined we lose about 3% of our body weight in water a day, or about 8 cups (see How Many Glasses of Water Should We Drink in a Day?). Consequently, for the longest time, water requirement guidelines for humanity were based on just one person.

There is evidence that not drinking enough may be associated with falls and fractures, heat stroke, heart disease, lung disorders, kidney disease, kidney stones, bladder and colon cancer, urinary tract infections, constipation, dry mouth, cavities, decreased immune function and cataract formation. The problem with many of these studies is that low water intake is associated with several unhealthy behaviors, such as low fruit and vegetable intake, more fast-food, less shopping at farmers markets. And who drinks lots of water? People who exercise a lot. No wonder they tend to have lower disease rates!

Only large and expensive randomized trials could settle these questions definitively. Given that water cannot be patented, such trials seem unlikely; who's going to pay for them? We're left with studies that find an association between disease and low water intake. But are people sick because they drink less, or are they drinking less because they're sick? There have been a few large prospective studies in which fluid intake is measured before disease develops. For example, a Harvard study of 48,000 men found that the risk of bladder cancer decreased by 7% for every extra daily cup of fluid we drink. Therefore, a high intake of water--like 8 cups a day--may reduce the risk of bladder cancer by about 50%, potentially saving thousands of lives.

The accompanying editorial commented that strategies to prevent the most prevalent cancers in the West are remarkably straightforward in principle. To prevent lung cancer, quit smoking; to prevent breast cancer, maintain your ideal body weight and exercise; and to prevent skin cancer, stay out of the sun. Now comes this seemingly simple way to reduce the risk of bladder cancer: drink more fluids.

Probably the best evidence we have for a cut off of water intake comes from the Adventist Health Study, in which 20,000 men and women were studied. About one-half were vegetarian, so they were also getting extra water by eating more fruits and vegetables. Those drinking 5 or more glasses of water a day had about half the risk of dying from heart disease compared to those who drank 2 or fewer glasses a day. Like the Harvard study, this protection was found after controlling for other factors such as diet and exercise. These data suggest that it was the water itself that was decreasing risk, perhaps by lowering blood viscosity (blood thickness).

Based on all the best evidence to date, authorities from Europe, the U.S. Institute of Medicine, and the World Health Organization recommend between 2.0 and 2.7 liters (8 to 11 cups) of water a day for women, and 2.5 to 3.7 liters (10 to 15 cups) a day for men. This includes water from all sources, not just beverages. We get about a liter from food and the water our body makes. So this translates into a recommendation for women to drink 4 to 7 cups of water a day and men 6 to 11 cups, assuming only moderate physical activity at moderate ambient temperatures.

We can also get water from all the other drinks we consume, including caffeinated drinks, with the exception of stronger alcoholic drinks like wines and spirits. Beer can leave you with more water than you started with, but wine actively dehydrates you. However, in the cancer and heart disease studies I mentioned above, the benefits were only found with increased water consumption, not other beverages.

I've previously touched on the cognitive benefits of proper hydration here: Does a Drink Of Water Make Children Smarter?

Surprised tea is hydrating? See my video Is Caffeinated Tea Dehydrating?

Surprised that the 8-a-day rested on such flimsy evidence? Unfortunately, so much of what we do in medicine has shaky underpinnings. That's the impetus behind the idea of evidence-based medicine (what a concept!). Ironically, this new movement may itself undermine some of the most effective treatments. See Evidence-Based Medicine or Evidence-Biased?

How else can we reduce our risk of bladder cancer? See Raw Broccoli and Bladder Cancer Survival.

What kind of water? I recommend tap water, which tends to be preferable from a chemical and microbial contamination standpoint. What about buying one of those fancy alkalizing machines? See Alkaline Water: a Scam?

It's so nice to have data on such a fundamental question. We have much to thank the Adventists for. You will see their studies cropping up frequently. See, for example, Plant-Based Diets and Diabetes, The Okinawa Diet: Living to 100, and Evidence-Based Eating.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. Image has been modified.

Original Link

The Best Diet to Prevent Kidney Stones

The Best Diet to Prevent Kidney Stones.jpeg

In my video How to Prevent Kidney Stones With Diet you can see what the jagged surface of a kidney stone looks like under a microscope. Imagine one of those scraping down your urinary canal! Kidney stones affect approximately 1 in 11 people in the United States. Twenty years ago it was only 1 in 20, representing a dramatic increase in the prevalence of the disease that started rising after World War II. Our first clue as to why was a study published in the 70's, which found a striking relationship between stone incidence and the consumption of animal protein. This was a population study, though, so it couldn't prove cause and effect.

That study inspired researchers in Britain to do an interventional study, adding animal protein to subjects' diets, such as an extra can of tuna fish a day, and measuring stone-forming risk factors in their urine. Participants' overall probability of forming stones increased 250% during those days they were eating that extra fish. And the so-called "high animal protein diet" was just enough to bring intake up to that of the average American. So Americans' intake of meat appears to markedly increase the risk of kidney stones.

What about consuming no meat at all? By the late 70's we knew that the only dietary factor consistently associated with kidney stones was animal protein. The higher the intake of animal protein, the more likely the individual was to not only get their first kidney stone, but to then suffer from subsequent multiple stones. This effect was not found for high protein intake in general, but specifically high animal protein intake. Conversely, a diet low in animal protein may dramatically reduce the overall probability of forming stones. This may explain the apparently low incidence of stones in vegetarian societies, so researchers advocated "a more vegetarian form of diet" as a means of reducing the risk.

It wasn't until 2014 that vegetarian kidney stone risk was studied in detail, though. Using hospital admissions data, researchers found that vegetarians were indeed at a lower risk of being hospitalized for kidney stones. It's not all or nothing, though. Among meat-eaters, increasing meat intake is associated with a higher risk of developing kidney stones, whereas a high intake of fresh fruit, fiber, and magnesium may reduce the risk.

Which animal protein is the worst? People who form kidney stones are commonly advised to restrict the intake of red meat to decrease stone risk, but what about chicken and fish? Despite compelling evidence that excessive animal protein consumption enhances the risk of stone formation, the effect of different sources of animal protein had not been explored until another study in 2014. Researchers compared the effects of salmon and cod, chicken breast meat, and burger and steak. In terms of uric acid production, they found that gram for gram fish may actually be worse. However, the overall effects were complex. Basically, stone formers should be counseled to limit the intake of all animal proteins, and not by just a little bit. Only those who markedly decrease their animal protein intake may expect to benefit.

Making our urine more alkaline can also help prevent the formation of kidney stones (and even dissolve and cure uric acid stones). How can you tell the pH of your urine? See my video Testing Your Diet with Pee & Purple Cabbage.

For more on kidney stones, see How to Treat Kidney Stones with Diet and Do Vitamin C Supplements Prevent Colds but Cause Kidney Stones?. And check out my overview of kidney health in How Not to Die from Kidney Disease.

Uric acid can also crystallize in our joints, but the good news is that there are natural treatments. See Gout Treatment with a Cherry on Top and Treating Gout with Cherry Juice.

Kidney stones are just one more reason that Plant Protein is Preferable.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

The Best Diet to Prevent Kidney Stones

The Best Diet to Prevent Kidney Stones.jpeg

In my video How to Prevent Kidney Stones With Diet you can see what the jagged surface of a kidney stone looks like under a microscope. Imagine one of those scraping down your urinary canal! Kidney stones affect approximately 1 in 11 people in the United States. Twenty years ago it was only 1 in 20, representing a dramatic increase in the prevalence of the disease that started rising after World War II. Our first clue as to why was a study published in the 70's, which found a striking relationship between stone incidence and the consumption of animal protein. This was a population study, though, so it couldn't prove cause and effect.

That study inspired researchers in Britain to do an interventional study, adding animal protein to subjects' diets, such as an extra can of tuna fish a day, and measuring stone-forming risk factors in their urine. Participants' overall probability of forming stones increased 250% during those days they were eating that extra fish. And the so-called "high animal protein diet" was just enough to bring intake up to that of the average American. So Americans' intake of meat appears to markedly increase the risk of kidney stones.

What about consuming no meat at all? By the late 70's we knew that the only dietary factor consistently associated with kidney stones was animal protein. The higher the intake of animal protein, the more likely the individual was to not only get their first kidney stone, but to then suffer from subsequent multiple stones. This effect was not found for high protein intake in general, but specifically high animal protein intake. Conversely, a diet low in animal protein may dramatically reduce the overall probability of forming stones. This may explain the apparently low incidence of stones in vegetarian societies, so researchers advocated "a more vegetarian form of diet" as a means of reducing the risk.

It wasn't until 2014 that vegetarian kidney stone risk was studied in detail, though. Using hospital admissions data, researchers found that vegetarians were indeed at a lower risk of being hospitalized for kidney stones. It's not all or nothing, though. Among meat-eaters, increasing meat intake is associated with a higher risk of developing kidney stones, whereas a high intake of fresh fruit, fiber, and magnesium may reduce the risk.

Which animal protein is the worst? People who form kidney stones are commonly advised to restrict the intake of red meat to decrease stone risk, but what about chicken and fish? Despite compelling evidence that excessive animal protein consumption enhances the risk of stone formation, the effect of different sources of animal protein had not been explored until another study in 2014. Researchers compared the effects of salmon and cod, chicken breast meat, and burger and steak. In terms of uric acid production, they found that gram for gram fish may actually be worse. However, the overall effects were complex. Basically, stone formers should be counseled to limit the intake of all animal proteins, and not by just a little bit. Only those who markedly decrease their animal protein intake may expect to benefit.

Making our urine more alkaline can also help prevent the formation of kidney stones (and even dissolve and cure uric acid stones). How can you tell the pH of your urine? See my video Testing Your Diet with Pee & Purple Cabbage.

For more on kidney stones, see How to Treat Kidney Stones with Diet and Do Vitamin C Supplements Prevent Colds but Cause Kidney Stones?. And check out my overview of kidney health in How Not to Die from Kidney Disease.

Uric acid can also crystallize in our joints, but the good news is that there are natural treatments. See Gout Treatment with a Cherry on Top and Treating Gout with Cherry Juice.

Kidney stones are just one more reason that Plant Protein is Preferable.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Benefits of Nutritional Yeast to Prevent the Common Cold

Benefits of Nutritional Yeast to Prevent the Common Cold.jpeg

Natural immunomodulators that can help regulate our immune system without side-effects have been sought for centuries, and all the while they've been sitting in the produce aisle. Plants produce thousand of active compounds, many of which modulate our immune system, but we can't forget the fungi (see Boosting Immunity While Reducing Inflammation).

Mushrooms have used for centuries as folk remedies, and for good reason. Some have been shown to boost immune function, so much so that a type of fiber found in shiitake mushrooms is approved for use as adjunct chemotherapy, injected intravenously to help treat a variety of cancers by rallying our immune defenses.

More than 6,000 papers have been published on these so-called beta glucans, but almost all of the data about preventing infections had come from petri dish or lab animal studies, until a few years ago when a series of experiments on athletes showed beneficial effects in marathon runners (see Preserving Immune Function in Athletes With Nutritional Yeast). What about the rest of us? We didn't know... until now.

As I explore in my video, Nutritional Yeast to Prevent the Common Cold, beta glucan fiber found in baker's, brewer's and nutritional yeast helps to maintain our body's defense against pathogens even in nonathletes, according to a double-blind, randomized, placebo-controlled trial. The recurrence of infections with the common cold was reduced by 25% in those that ate the equivalent of about a spoonful of nutritional yeast a day, and had fewer cold-related sleeping difficulties when they did get sick.

What about half a spoonful a day? Still worked! Subjects experienced a big drop in common cold incidence and a reduction in symptoms as well. Why is this? This study found that not only were upper respiratory infection symptoms diminished, but that mood states appeared to improve, for example a significant boost in feelings of "vigor." So the researchers suggest that maybe the yeast fiber is able to counteract the negative effects of stress on the immune system.

In terms of side-effects, two folks reported stomachaches, but they were both in the placebo group.

Unlike antibiotics and antivirals, which are designed to kill the pathogen directly, these yeast compounds instead appear to work by stimulating our immune defenses, and as such don't share the same antibiotic side effects. They stimulate our immune defenses presumably because our body recognizes them as foreign. But if it's treated like an invader, might it trigger an inflammatory response? Turns out these fiber compounds may actually have an anti-inflammatory effect, suggesting nutritional yeast may offer the best of both worlds, boosting the infection fighting side of the immune system while suppressing inflammatory components.

Yeast is high in purines, so those with gout, uric acid kidney stones, and new organ transplant recipients may want to keep their intake to less than a teaspoon a day. But is there any downside for everyone else? In California some packages of nutritional yeast are slapped with prop 65 warning stickers, suggesting there's something in it exceeding cancer or birth defect safety limits. I called around to the companies and it turns out the problem is lead. California state law says a product cannot contain more than half of a microgram of lead per daily serving, so I contacted the six brands I knew about and asked them how much lead was in their products.

KAL originally said "<5 ppm," but when we called back they said "<3 ppm." Even if it's 3, that translates into less than 45 micrograms per serving, nearly a 100 times more than the California limit. But perhaps that's better than Bob's Red Mill or Frontier Coop, who evidently don't test at all. But at least they got back to me. Redstar brand failed to respond to multiple attempts to contact them. Now Foods said they test for lead and claim that at least their recent batches meet the less than a half a microgram California standard. Unfortunately, despite repeated requests they would not provide me with documentation to substantiate their numbers. My favorite response was from Bragg's who sent me the analysis certificate from the lab showing less than 0.01 ppm, which means at most less than half the California standard, which I believe is the most stringent in the world. To put the numbers in context, in determining how much lead manufacturers can put into candy likely to be frequently consumed by small children, the Food and Drug Administration would allow about 2 micrograms a day in the form of lollipops, but as far as I'm concerned the less lead the better.

I was so frustrated by the lack of transparency I decided to test them for lead myself. NutritionFacts.org hired an independent lab to conduct our own tests for lead and shipped out 8 samples of nutritional yeast in their original package. The lab used standard practices for lead testing known as Official Methods of Analysis set by AOAC International. Lab technicians determined the lead values based on California Prop 65 standards. Here are the results from the brands we tested:

Bob's Red Mill - Test report shows no detectable lead (<0.01 ppm).

Bragg - Test report shows no detectable lead (< 0.01 ppm).

Dr. Fuhrman - Test report shows no detectable lead (< 0.01 ppm).

Frontier Coop - Test report shows lead levels at 0.021 ppm. It would take six tablespoons a day (based on the manufacture's listed density) to exceed the California Office of Environmental Health Hazard Assessment Maximum Allowable Dose Level (MADL) for chemicals causing reproductive toxicity.*

KAL - Test report shows lead levels at 0.011 ppm. It would take seven tablespoons a day to exceed the MADL.*

NOW Foods - Test report shows no detectable lead (< 0.01 ppm).

Red Star - Test report shows no detectable lead (< 0.01 ppm).

Whole Foods - Test report shows lead levels at 0.012 ppm. It would take six tablespoons a day to exceed the MADL.*

So what do all those numbers mean? None of the brands tested exceeded California prop 65 standards. No matter what brand, consuming a typical serving (2 tablespoons) per day is still well within safe limits.

In health,
Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

* The Maximum Allowable Dose Level for lead as a developmental toxin is 0.5 micrograms a day. How are MADL's calculated? Basically scientists figure out what the "no observable effect level" is, the level at which no birth defects or reproductive toxicity can be found, and then introduce a 1000-fold safety buffer. So for example, let's say there's some chemical that causes birth defects if expectant moms are exposed to two drops of the chemical a day, but there's no evidence that one drop a day is harmful. Do they set the Maximum Allowable Dose Level at one drop? No, they set it at 1/1000th of a drop to account for scientific uncertainty and to err on the side of caution. So by saying six tablespoons a day of nutritional yeast may exceed the MADL is in effect saying that the level of lead found in 6,000 tablespoons of nutritional yeast may cause birth defects. Like mercury, though, as far as I'm concerned the less lead exposure the better. I hope this will inspire companies to do further testing to see if the levels we found were just flukes.

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Benefits of Nutritional Yeast to Prevent the Common Cold

Benefits of Nutritional Yeast to Prevent the Common Cold.jpeg

Natural immunomodulators that can help regulate our immune system without side-effects have been sought for centuries, and all the while they've been sitting in the produce aisle. Plants produce thousand of active compounds, many of which modulate our immune system, but we can't forget the fungi (see Boosting Immunity While Reducing Inflammation).

Mushrooms have used for centuries as folk remedies, and for good reason. Some have been shown to boost immune function, so much so that a type of fiber found in shiitake mushrooms is approved for use as adjunct chemotherapy, injected intravenously to help treat a variety of cancers by rallying our immune defenses.

More than 6,000 papers have been published on these so-called beta glucans, but almost all of the data about preventing infections had come from petri dish or lab animal studies, until a few years ago when a series of experiments on athletes showed beneficial effects in marathon runners (see Preserving Immune Function in Athletes With Nutritional Yeast). What about the rest of us? We didn't know... until now.

As I explore in my video, Nutritional Yeast to Prevent the Common Cold, beta glucan fiber found in baker's, brewer's and nutritional yeast helps to maintain our body's defense against pathogens even in nonathletes, according to a double-blind, randomized, placebo-controlled trial. The recurrence of infections with the common cold was reduced by 25% in those that ate the equivalent of about a spoonful of nutritional yeast a day, and had fewer cold-related sleeping difficulties when they did get sick.

What about half a spoonful a day? Still worked! Subjects experienced a big drop in common cold incidence and a reduction in symptoms as well. Why is this? This study found that not only were upper respiratory infection symptoms diminished, but that mood states appeared to improve, for example a significant boost in feelings of "vigor." So the researchers suggest that maybe the yeast fiber is able to counteract the negative effects of stress on the immune system.

In terms of side-effects, two folks reported stomachaches, but they were both in the placebo group.

Unlike antibiotics and antivirals, which are designed to kill the pathogen directly, these yeast compounds instead appear to work by stimulating our immune defenses, and as such don't share the same antibiotic side effects. They stimulate our immune defenses presumably because our body recognizes them as foreign. But if it's treated like an invader, might it trigger an inflammatory response? Turns out these fiber compounds may actually have an anti-inflammatory effect, suggesting nutritional yeast may offer the best of both worlds, boosting the infection fighting side of the immune system while suppressing inflammatory components.

Yeast is high in purines, so those with gout, uric acid kidney stones, and new organ transplant recipients may want to keep their intake to less than a teaspoon a day. But is there any downside for everyone else? In California some packages of nutritional yeast are slapped with prop 65 warning stickers, suggesting there's something in it exceeding cancer or birth defect safety limits. I called around to the companies and it turns out the problem is lead. California state law says a product cannot contain more than half of a microgram of lead per daily serving, so I contacted the six brands I knew about and asked them how much lead was in their products.

KAL originally said "<5 ppm," but when we called back they said "<3 ppm." Even if it's 3, that translates into less than 45 micrograms per serving, nearly a 100 times more than the California limit. But perhaps that's better than Bob's Red Mill or Frontier Coop, who evidently don't test at all. But at least they got back to me. Redstar brand failed to respond to multiple attempts to contact them. Now Foods said they test for lead and claim that at least their recent batches meet the less than a half a microgram California standard. Unfortunately, despite repeated requests they would not provide me with documentation to substantiate their numbers. My favorite response was from Bragg's who sent me the analysis certificate from the lab showing less than 0.01 ppm, which means at most less than half the California standard, which I believe is the most stringent in the world. To put the numbers in context, in determining how much lead manufacturers can put into candy likely to be frequently consumed by small children, the Food and Drug Administration would allow about 2 micrograms a day in the form of lollipops, but as far as I'm concerned the less lead the better.

I was so frustrated by the lack of transparency I decided to test them for lead myself. NutritionFacts.org hired an independent lab to conduct our own tests for lead and shipped out 8 samples of nutritional yeast in their original package. The lab used standard practices for lead testing known as Official Methods of Analysis set by AOAC International. Lab technicians determined the lead values based on California Prop 65 standards. Here are the results from the brands we tested:

Bob's Red Mill - Test report shows no detectable lead (<0.01 ppm).

Bragg - Test report shows no detectable lead (< 0.01 ppm).

Dr. Fuhrman - Test report shows no detectable lead (< 0.01 ppm).

Frontier Coop - Test report shows lead levels at 0.021 ppm. It would take six tablespoons a day (based on the manufacture's listed density) to exceed the California Office of Environmental Health Hazard Assessment Maximum Allowable Dose Level (MADL) for chemicals causing reproductive toxicity.*

KAL - Test report shows lead levels at 0.011 ppm. It would take seven tablespoons a day to exceed the MADL.*

NOW Foods - Test report shows no detectable lead (< 0.01 ppm).

Red Star - Test report shows no detectable lead (< 0.01 ppm).

Whole Foods - Test report shows lead levels at 0.012 ppm. It would take six tablespoons a day to exceed the MADL.*

So what do all those numbers mean? None of the brands tested exceeded California prop 65 standards. No matter what brand, consuming a typical serving (2 tablespoons) per day is still well within safe limits.

In health,
Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

* The Maximum Allowable Dose Level for lead as a developmental toxin is 0.5 micrograms a day. How are MADL's calculated? Basically scientists figure out what the "no observable effect level" is, the level at which no birth defects or reproductive toxicity can be found, and then introduce a 1000-fold safety buffer. So for example, let's say there's some chemical that causes birth defects if expectant moms are exposed to two drops of the chemical a day, but there's no evidence that one drop a day is harmful. Do they set the Maximum Allowable Dose Level at one drop? No, they set it at 1/1000th of a drop to account for scientific uncertainty and to err on the side of caution. So by saying six tablespoons a day of nutritional yeast may exceed the MADL is in effect saying that the level of lead found in 6,000 tablespoons of nutritional yeast may cause birth defects. Like mercury, though, as far as I'm concerned the less lead exposure the better. I hope this will inspire companies to do further testing to see if the levels we found were just flukes.

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Phytates in Beans: Anti-Nutrient or Anti-Cancer?

NF-May28 Phytates for the Treatment of Cancer.jpg

In my videos, Phytates in the Prevention of Cancer and Phytates for Rehabilitating Cancer Cells, I described how phytates in beans may be the reason why legumes are so successful in preventing cancer and re-educating cancer cells. What about phytates for the treatment of cancer?

Colorectal cancer is the second leading cause of cancer death in the United States. It arises from "adenomatous polyps," meaning that colon cancer starts out as a benign little bump called a polyp and then grows into cancer that can eventually spread to other organs and kill. So the National Cancer Institute funded the Polyp Prevention Trial, highlighted in my video, Phytates for the Treatment of Cancer, to determine the effects of a high-fiber, high fruit and vegetable, low-fat diet.

Researchers found no significant associations between polyp formation and overall change in fruit and vegetable consumption. However, those with the greatest increase in bean intake only had about a third of the odds of advanced polyps popping up. It could have been the fiber in the beans, but there's lots of fiber in fruits and vegetables, too. So it may have been the phytate.

If the tumors develop from polyps, they still need to spread. Tumor growth, invasion, and metastasis are multistep processes that include cell proliferation, digestion through the surrounding tissue, and migration through barrier membranes to reach the bloodstream so the tumor can establish new proliferating colonies of cancer cells. A critical event in tumor cell invasion is the first step: the tunneling through the surrounding matrix. To do this, the cancer cells use a set of enzymes called matrix metalloproteinases. This is where phytates might come in. We've known that phytates inhibit cancer cell migration in vitro, and now perhaps we know why. Phytates help block the ability of cancer cells to produce the tumor invasion enzyme in the first place (at least for human colon and breast cancer cells).

So what happens if you give phytates to breast cancer patients? Although a few case studies where phytates were given in combination with chemotherapy clearly showed encouraging data, organized, controlled, randomized clinical studies were never done--until now. Fourteen women with invasive breast cancer were divided randomly into two groups. One group got extra phytates; the other got placebo. At the end of six months, the phytate group had a better quality of life, significantly more functionality, fewer symptoms from the chemo, and did not get the drop in immune cells and platelets chemo patients normally experience.

What are the potential side effects of phytates? Less heart disease, less diabetes, and fewer kidney stones.

Because cancer development is such an extended process--it can take decades to grow--we need cancer preventive agents that we can take long-term. Phytates, which naturally occur in beans, grains, nuts, and seeds, seem to fit the bill.

In the past, there were concerns that the intake of foods high in phytates might reduce the bioavailability of dietary minerals, but recent studies demonstrate that this co-called "anti-nutrient" effect can be manifested only when large quantities of phytates are consumed in combination with a nutrient poor diet. For example, there used to be a concern that phytate consumption might lead to calcium deficiency, which then led to weakened bones, but researchers discovered that the opposite was true, that phytates actually protect against osteoporosis (See Phytates for the Prevention of Osteoporosis). In essence, phytates have many characteristics of a vitamin, contrary to the established and, unfortunately, still existing dogma among nutritionists regarding its 'anti-nutrient' role.

As one paper in the International Journal of Food Science & Technology suggests:

"Given the numerous health benefits, phytates participation in important intracellular biochemical pathways, normal physiological presence in our cells, tissues, plasma, urine, etc., the levels of which fluctuate with intake, epidemiological correlates of phytate deficiency with disease and reversal of those conditions by adequate intake, and safety - all strongly suggest for phytates inclusion as an essential nutrient, perhaps a vitamin."

The paper concludes that inclusion of phytates in our diet for prevention and therapy of various ailments, cancer in particular, is warranted.

More on preventing tumor invasion and metastasis in:

Other foods that can help stop the progression of precancerous lesions (like the adenomatous polyps) are profiled in Strawberries versus Esophageal Cancer and Black Raspberries versus Oral Cancer.

There's a substance in mushrooms that's also another "essential" nutrient candidate. See Ergothioneine: A New Vitamin?

-Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death, More Than an Apple a Day, and From Table to Able.

Image Credit: The Ewan / Flickr

Original Link

How Phytates Fight Cancer Cells

NF-May26 Phytates for Rehabilitating Cancer Cells.jpg

Phytate is a compound found in beans, grains, nuts and seeds. The average daily intake of phytate in vegetarian diets is about twice that of those eating mixed diets of plant and animal foods, which may help explain their low cancer rates. Aside from helping to prevent cancer, dietary phytate has been reported to help prevent kidney stone formation, protect against diabetes mellitus, dental cavities, and heart disease.

Do all these potentially beneficial effects sound too good to be true? Are there other examples of compounds made by plants that can have benefits across multiple diseases? Why yes! Aspirin, for example, which is found throughout the plant kingdom may also account for a variety of plant-based benefits (See Aspirin Levels in Plant Foods).

But of all the things phytates can do, the anticancer activity of phytate (also known as phytic acid, IP6, or inositol hexaphosphate), is considered one of its most important beneficial activities. Dietary phytates are quickly absorbed from the gastrointestinal tract and rapidly taken up by cancer cells throughout the body, and have been shown to inhibit the growth of all tested cancerous cell lines in vitro. Phytates have been shown to inhibit the growth of human leukemia cells, colon cancer cells, both estrogen receptor-positive and negative breast cancer cells, voicebox cancer, cervical cancer, prostate cancer, liver tumors, pancreatic, melanoma, and muscle cancers. All at the same time not affecting normal cells. That's the most important expectation of a good anticancer agent: the ability to only affect cancerous cells and to leave normal cells alone.

In my video, Phytates for Rehabilitating Cancer Cells, you can see how leukemia cells taken from cancer patients are killed by phytates, whereas normal bone marrow cells, are spared. This may explain why bean extracts kill off colon cancer cells in vitro, but leave normal colon cells alone.

What are the mechanisms of action by which phytates battle cancer? In other words, how do phytates fight? How don't they fight? Phytate targets cancer through multiple pathways, a combination of antioxidant, anti-inflammatory, immune-enhancing activities, detox, differentiation, and anti-angiogenesis. In other words, phytate appears to affect all the principal pathways of malignancy.

The antioxidative property is one of the most impressive characteristics of phytate. In fact that's why the meat industry adds phytates to meat to prevent the fat oxidation that begins at the moment of slaughter. Phytates can also act on our immune functions by augmenting natural killer cell activity, the cells in our body that hunt down and dispose of cancer cells, as well as neutrophils, which help form our first line of defense. And then phytates starve tumors as more of a last line of defense. Not only can phytates block the formation of new blood vessels that may be feeding tumors, but disrupt pre-formed capillary tubes, indicating that phytates may not just help blockade tumors, but actively cut off existing supply lines.

What's really remarkable about phytate, though, is that unlike most other anti-cancer agents, it not only causes a reduction in cancer cell growth but also enhances differentiation, meaning it causes cancer cells to stop acting like cancer cells and go back to acting like normal cells. You can see this with colon cancer cells for example. In the presence of phytates, human colon cancer cells mature to structurally and behaviorally resemble normal cells. And this has been demonstrated in leukemia cells, prostate cancer, breast cancer, and muscle cancer cells as well.

For more on the cancer and phytate connection, check out Phytates for the Prevention of Cancer and Phytates for the Treatment of Cancer.

This video reminds me of my video on the spice, turmeric, Turmeric Curcumin Reprogramming Cancer Cell Death.

What else can we eat to improve the cancer-fighting front of our immune system? See Boosting Natural Killer Cell Activity.

More on the concept of starving tumors of their blood supply in Anti-Angiogenesis: Cutting Off Tumor Supply Lines.

Is there clinical evidence of plants actually reversing cancer progression? You won't believe your eyes:

-Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death, More Than an Apple a Day, and From Table to Able.

Image Credit: Avi / Flickr

Original Link