Plant versus Animal Iron

Plant versus Animal Iron.jpeg

It is commonly thought that those who eat plant-based diets may be more prone to iron deficiency, but it turns out that they're no more likely to suffer from iron deficiency anemia than anybody else. This may be because not only do those eating meat-free diets tend to get more fiber, magnesium, and vitamins like A, C, and E, but they also get more iron.

The iron found predominantly in plants is non-heme iron, which isn't absorbed as well as the heme iron found in blood and muscle, but this may be a good thing. As seen in my video, The Safety of Heme vs. Non-Heme Iron, avoidance of heme iron may be one of the key elements of plant-based protection against metabolic syndrome, and may also be beneficial in lowering the risk from other chronic diseases such as heart disease.

The data linking coronary heart disease and the intake of iron, in general, has been mixed. This inconsistency of evidence may be because of where the iron comes from. The majority of total dietary iron is non-heme iron, coming mostly from plants. So, total iron intake is associated with lower heart disease risk, but iron intake from meat is associated with significantly higher risk for heart disease. This is thought to be because iron can act as a pro-oxidant, contributing to the development of atherosclerosis by oxidizing cholesterol with free radicals. The risk has been quantified as a 27% increase in coronary heart disease risk for every 1 milligram of heme iron consumed daily.

The same has been found for stroke risk. The studies on iron intake and stroke have had conflicting results, but that may be because they had never separated out heme iron from non-heme iron... until now. Researchers found that the intake of meat (heme) iron, but not plant (non-heme) iron, was associated with an increased risk of stroke.

The researchers also found that higher intake of heme iron--but not total or plant (non-heme) iron--was significantly associated with greater risk for type 2 diabetes. There may be a 16% increase in risk for type 2 diabetes for every 1 milligram of heme iron consumed daily.

The same has also been found for cancer, with up to 12% increased risk for every milligram of daily heme iron exposure. In fact, we can actually tell how much meat someone is eating by looking at their tumors. To characterize the mechanisms underlying meat-related lung cancer development, researchers asked lung cancer patients how much meat they ate and examined the gene expression patterns in their tumors. They identified a signature pattern of heme-related gene expression. Although they looked specifically at lung cancer, they expect these meat-related gene expression changes may occur in other cancers as well.

We do need to get enough iron, but only about 3% of premenopausal white women have iron deficiency anemia these days. However, the rates are worse in African and Mexican Americans. Taking into account our leading killers--heart disease, cancer, and diabetes--the healthiest source of iron appears to be non-heme iron, found naturally in abundance in whole grains, beans, split peas, chickpeas, lentils, dark green leafy vegetables, dried fruits, nuts, and seeds.

But how much money can be made on beans, though? The processed food industry came up with a blood-based crisp bread, made out of rye flour and blood from cattle and pigs, which is one of the most concentrated sources of heme iron, about two-thirds more than blood from chickens. If blood-based crackers don't sound particularly appetizing, you can always snack on cow blood cookies. And there are always blood-filled biscuits, whose filling has been described as "a dark-colored, chocolate flavored paste with a very pleasant taste." (It's dark-colored because spray-dried pig blood can have a darkening effect on the food product's color.) The worry is not the color or taste, it's the heme iron, which, because of its potential cancer risk, is not considered safe to add to foods intended for the general population.

Previously, I've touched on the double-edged iron sword in Risk Associated With Iron Supplements and Phytates for the Prevention of Cancer. It may also help answer Why Was Heart Disease Rare in the Mediterranean?

Those eating plant-based diets get more of most nutrients since whole plant foods are so nutrient dense. See Nutrient-Dense Approach to Weight Management.

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

Plant versus Animal Iron

Plant versus Animal Iron.jpeg

It is commonly thought that those who eat plant-based diets may be more prone to iron deficiency, but it turns out that they're no more likely to suffer from iron deficiency anemia than anybody else. This may be because not only do those eating meat-free diets tend to get more fiber, magnesium, and vitamins like A, C, and E, but they also get more iron.

The iron found predominantly in plants is non-heme iron, which isn't absorbed as well as the heme iron found in blood and muscle, but this may be a good thing. As seen in my video, The Safety of Heme vs. Non-Heme Iron, avoidance of heme iron may be one of the key elements of plant-based protection against metabolic syndrome, and may also be beneficial in lowering the risk from other chronic diseases such as heart disease.

The data linking coronary heart disease and the intake of iron, in general, has been mixed. This inconsistency of evidence may be because of where the iron comes from. The majority of total dietary iron is non-heme iron, coming mostly from plants. So, total iron intake is associated with lower heart disease risk, but iron intake from meat is associated with significantly higher risk for heart disease. This is thought to be because iron can act as a pro-oxidant, contributing to the development of atherosclerosis by oxidizing cholesterol with free radicals. The risk has been quantified as a 27% increase in coronary heart disease risk for every 1 milligram of heme iron consumed daily.

The same has been found for stroke risk. The studies on iron intake and stroke have had conflicting results, but that may be because they had never separated out heme iron from non-heme iron... until now. Researchers found that the intake of meat (heme) iron, but not plant (non-heme) iron, was associated with an increased risk of stroke.

The researchers also found that higher intake of heme iron--but not total or plant (non-heme) iron--was significantly associated with greater risk for type 2 diabetes. There may be a 16% increase in risk for type 2 diabetes for every 1 milligram of heme iron consumed daily.

The same has also been found for cancer, with up to 12% increased risk for every milligram of daily heme iron exposure. In fact, we can actually tell how much meat someone is eating by looking at their tumors. To characterize the mechanisms underlying meat-related lung cancer development, researchers asked lung cancer patients how much meat they ate and examined the gene expression patterns in their tumors. They identified a signature pattern of heme-related gene expression. Although they looked specifically at lung cancer, they expect these meat-related gene expression changes may occur in other cancers as well.

We do need to get enough iron, but only about 3% of premenopausal white women have iron deficiency anemia these days. However, the rates are worse in African and Mexican Americans. Taking into account our leading killers--heart disease, cancer, and diabetes--the healthiest source of iron appears to be non-heme iron, found naturally in abundance in whole grains, beans, split peas, chickpeas, lentils, dark green leafy vegetables, dried fruits, nuts, and seeds.

But how much money can be made on beans, though? The processed food industry came up with a blood-based crisp bread, made out of rye flour and blood from cattle and pigs, which is one of the most concentrated sources of heme iron, about two-thirds more than blood from chickens. If blood-based crackers don't sound particularly appetizing, you can always snack on cow blood cookies. And there are always blood-filled biscuits, whose filling has been described as "a dark-colored, chocolate flavored paste with a very pleasant taste." (It's dark-colored because spray-dried pig blood can have a darkening effect on the food product's color.) The worry is not the color or taste, it's the heme iron, which, because of its potential cancer risk, is not considered safe to add to foods intended for the general population.

Previously, I've touched on the double-edged iron sword in Risk Associated With Iron Supplements and Phytates for the Prevention of Cancer. It may also help answer Why Was Heart Disease Rare in the Mediterranean?

Those eating plant-based diets get more of most nutrients since whole plant foods are so nutrient dense. See Nutrient-Dense Approach to Weight Management.

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 Nutrition Education Do Doctors Get?

How Much Nutrition Education Do Doctors Get?.jpeg

In the United States, most deaths are preventable and related to nutrition. Given that the number-one cause of death and the number-one cause of disability in this country is diet, surely nutrition is the number-one subject taught in medical school, right? Sadly, that is not the case.

As shown in my video, Physician's May Be Missing Their Most Important Tool, a group of prominent physicians wrote in 2014 that "nutrition receives little attention in medical practice" and "the reason stems, in large part, from the severe deficiency of nutrition education at all levels of medical training." They note this is particularly shocking since it has been proven that a whole foods, plant-based diet low in animal products and refined carbohydrates can reverse coronary heart disease--our number-one killer--and provide potent protection against other leading causes fof death such as cancer and type 2 diabetes.

So, how has medical education been affected by this knowledge? Medical students are still getting less than 20 hours of nutrition education over 4 years, and even most of that has limited clinical relevance. Thirty years ago, only 37 percent of medical schools had a single course in nutrition. According to the most recent national survey, that number has since dropped to 27 percent. And it gets even worse after students graduate.

According to the official list of all the requirements for those specializing in cardiology, Fellows must perform at least 50 stress tests, participate in at least 100 catheterizations, and so on. But nowhere in the 34-page list of requirements is there any mention of nutrition. Maybe they leave that to the primary care physicians? No. In the official 35-page list of requirements for internal medicine doctors, once again, nutrition doesn't get even a single mention.

There are no requirements for nutrition before medical school either. Instead, aspiring doctors need to take courses like calculus, organic chemistry, and physics. Most of these common pre-med requirements are irrelevant to the practice of medicine and are primarily used to "weed out" students. Shouldn't we be weeding out based on skills a physician actually uses? An important paper published in the Archives of Internal Medicine states: "The pernicious and myopic nature of this process of selection becomes evident when one realizes that those qualities that may lead to success in a premedical organic chemistry course...[like] a brutal competitiveness, an unquestioning, meticulous memorization, are not necessarily the same qualities that are present in a competent clinician."

How about requiring a course in nutrition instead of calculus, or ethics instead of physics?

Despite the neglect of nutrition in medical education, physicians are considered by the public to be among the most trusted sources for information related to nutrition. But if doctors don't know what they're talking about, they could actually be contributing to diet-related disease. If we're going to stop the prevailing trend of chronic illness in the United States, physicians need to become part of the solution.

There's still a lot to learn about the optimal diet, but we don't need a single additional study to take nutrition education seriously right now. It's health care's low-hanging fruit. While we've had the necessary knowledge for some time, what we've been lacking is the will to put that knowledge into practice. If we emphasized the powerful role of nutrition, we could dramatically reduce suffering and needless death.

Take, for example, the "Million Hearts" initiative. More than 2 million Americans have a heart attack or stroke each year. In 2011, U.S. federal, state, and local government agencies launched the Million Hearts initiative to prevent 1 million of the 10 million heart attacks and strokes that will occur in the next 5 years. "But why stop at a million?" a doctor asked in the American Journal of Cardiology. Already, we possess all the information needed to eradicate atherosclerotic disease, which is our number-one killer while being virtually nonexistent in populations who consume plant-based diets. Some of the world's most renowned cardiovascular pathologists have stated we just need to get our cholesterol low enough in order to not only prevent--but also reverse--the disease in more than 80% of patients. We can open up arteries without drugs and surgery, and stabilize or improve blood flow in 99% of those who choose to eat healthily and clean up their bad habits. We can essentially eliminate our risk of having a heart attack even in the most advanced cases of heart disease.

Despite this, medical students aren't even taught these concepts while they're in school. Instead, the focus is on cutting people open, which frequently provides only symptomatic relief because we're not treating the actual cause of the disease. Fixing medical education is the solution to this travesty. Knowledge of nutrition can help doctors eradicate the world's leading killer.

I've previously addressed how Doctors Tend to Know Less Than They Think About Nutrition, which is no surprise given most medical schools in the United States fail to provide even a bare minimum of nutrition training (see Medical School Nutrition Education), with mainstream medical associations even actively lobbying against additional nutrition training.

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 Nutrition Education Do Doctors Get?

How Much Nutrition Education Do Doctors Get?.jpeg

In the United States, most deaths are preventable and related to nutrition. Given that the number-one cause of death and the number-one cause of disability in this country is diet, surely nutrition is the number-one subject taught in medical school, right? Sadly, that is not the case.

As shown in my video, Physician's May Be Missing Their Most Important Tool, a group of prominent physicians wrote in 2014 that "nutrition receives little attention in medical practice" and "the reason stems, in large part, from the severe deficiency of nutrition education at all levels of medical training." They note this is particularly shocking since it has been proven that a whole foods, plant-based diet low in animal products and refined carbohydrates can reverse coronary heart disease--our number-one killer--and provide potent protection against other leading causes fof death such as cancer and type 2 diabetes.

So, how has medical education been affected by this knowledge? Medical students are still getting less than 20 hours of nutrition education over 4 years, and even most of that has limited clinical relevance. Thirty years ago, only 37 percent of medical schools had a single course in nutrition. According to the most recent national survey, that number has since dropped to 27 percent. And it gets even worse after students graduate.

According to the official list of all the requirements for those specializing in cardiology, Fellows must perform at least 50 stress tests, participate in at least 100 catheterizations, and so on. But nowhere in the 34-page list of requirements is there any mention of nutrition. Maybe they leave that to the primary care physicians? No. In the official 35-page list of requirements for internal medicine doctors, once again, nutrition doesn't get even a single mention.

There are no requirements for nutrition before medical school either. Instead, aspiring doctors need to take courses like calculus, organic chemistry, and physics. Most of these common pre-med requirements are irrelevant to the practice of medicine and are primarily used to "weed out" students. Shouldn't we be weeding out based on skills a physician actually uses? An important paper published in the Archives of Internal Medicine states: "The pernicious and myopic nature of this process of selection becomes evident when one realizes that those qualities that may lead to success in a premedical organic chemistry course...[like] a brutal competitiveness, an unquestioning, meticulous memorization, are not necessarily the same qualities that are present in a competent clinician."

How about requiring a course in nutrition instead of calculus, or ethics instead of physics?

Despite the neglect of nutrition in medical education, physicians are considered by the public to be among the most trusted sources for information related to nutrition. But if doctors don't know what they're talking about, they could actually be contributing to diet-related disease. If we're going to stop the prevailing trend of chronic illness in the United States, physicians need to become part of the solution.

There's still a lot to learn about the optimal diet, but we don't need a single additional study to take nutrition education seriously right now. It's health care's low-hanging fruit. While we've had the necessary knowledge for some time, what we've been lacking is the will to put that knowledge into practice. If we emphasized the powerful role of nutrition, we could dramatically reduce suffering and needless death.

Take, for example, the "Million Hearts" initiative. More than 2 million Americans have a heart attack or stroke each year. In 2011, U.S. federal, state, and local government agencies launched the Million Hearts initiative to prevent 1 million of the 10 million heart attacks and strokes that will occur in the next 5 years. "But why stop at a million?" a doctor asked in the American Journal of Cardiology. Already, we possess all the information needed to eradicate atherosclerotic disease, which is our number-one killer while being virtually nonexistent in populations who consume plant-based diets. Some of the world's most renowned cardiovascular pathologists have stated we just need to get our cholesterol low enough in order to not only prevent--but also reverse--the disease in more than 80% of patients. We can open up arteries without drugs and surgery, and stabilize or improve blood flow in 99% of those who choose to eat healthily and clean up their bad habits. We can essentially eliminate our risk of having a heart attack even in the most advanced cases of heart disease.

Despite this, medical students aren't even taught these concepts while they're in school. Instead, the focus is on cutting people open, which frequently provides only symptomatic relief because we're not treating the actual cause of the disease. Fixing medical education is the solution to this travesty. Knowledge of nutrition can help doctors eradicate the world's leading killer.

I've previously addressed how Doctors Tend to Know Less Than They Think About Nutrition, which is no surprise given most medical schools in the United States fail to provide even a bare minimum of nutrition training (see Medical School Nutrition Education), with mainstream medical associations even actively lobbying against additional nutrition training.

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

Can Oatmeal Reverse Heart Disease?

Can Oatmeal Reverse Heart Disease?.jpeg

Fiber continues to be singled out as a nutrient of public health concern. We're getting only about half the minimum recommended intake on average. There is a fiber gap in America. Less than 3 percent meet the recommended minimum. This means that less than 3 percent of all Americans eat enough whole plant foods, the only place fiber is found in abundance. If even half of the adult population ate 3 more grams a day--a quarter cup of beans or a bowl of oatmeal--we could potentially save billions in medical costs. And that's just for constipation! The consumption of plant foods, of fiber-containing foods, may reduce the risk for diabetes, heart disease, stroke, cancer, and obesity as well.

The first to make this link between fiber intake and killer disease was probably Dr. Hugh Trowell. He spent 30 years practicing medicine in Africa and suspected it was the Africans high consumption of corn, millet, sweet potatoes, greens, and beans that protected them from chronic disease. This twisted into the so-called "fiber hypothesis," but Trowell didn't think it was the fiber itself, but the high-fiber foods themselves that were protective. There are hundreds of different substances in whole plant foods besides fiber that may have beneficial effects. For example, the fiber in oatmeal can lower our blood cholesterol levels so that less gets stuck in our arteries, but there also are anti-inflammatory and antioxidant phytonutrients in oats that can prevent atherosclerotic build-up and then help maintain arterial function (see Can Oatmeal Reverse Heart Disease?).

Visionaries like Trowell were not entrapped by the reductionist "simple-minded" focus on dietary fiber and insisted that the whole plant foods should receive the emphasis. Fiber intake was just a marker for plant food intake. Those with the highest fiber intake and the lowest cholesterol were those whose who ate exclusively plant-based diets.

Risk factors like cholesterol are one thing, but can these individual foods actually affect the progression of heart disease, the #1 killer of Americans? We didn't know until 2005. Hundreds of older women were subjected to coronary angiograms, where we inject dye into the coronary arteries of the heart to see how wide open they are. Each participant got an angiogram at the beginning of the study and one a few years later, all while researchers analyzed their diets. The arteries of women eating less than a serving of whole grains a day significantly narrowed, whereas the arteries of women who ate just a single serving or more also significantly narrowed, but they narrowed less. These were all women with heart disease eating the standard American diet, so their arteries were progressively clogging shut. But there was significantly less clogging in the women eating more whole grains, significantly less progression of their atherosclerosis. A similar slowing of their disease might be expected from taking cholesterol-lowering statin drugs. But do we want to just slow the rate at which we die from heart disease, or do we want to not die from heart disease at all?

A strictly plant-based diet has been shown to reverse the progression of heart disease, opening up arteries back up. Yes, whole grains, like drugs, can help counter the artery-clogging effects of the rest of the diet. Having oatmeal with bacon and eggs is better than just eating bacon and eggs, but why not stop eating an artery-clogging diet altogether?

Oatmeal offers a lot more than fiber, though. See Oatmeal Lotion for Chemotherapy-Induced Rash and Can Oatmeal Help Fatty Liver Disease?

Trowell's work had a big influence on Dr. Denis Burkitt. See Dr. Burkitt's F-Word Diet.

This reminds me of other interventions like hibiscus tea for high blood pressure (Hibiscus Tea vs. Plant-Based Diets for Hypertension) or amla for diabetes (Amla Versus Diabetes). Better to reverse the disease completely.

And for an overview of how whole plant foods affect disease risks, be sure to check out the videos on our new Introduction page!

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: Rachel Hathaway / Flickr. This image has been modified.

Original Link

Can Oatmeal Reverse Heart Disease?

Can Oatmeal Reverse Heart Disease?.jpeg

Fiber continues to be singled out as a nutrient of public health concern. We're getting only about half the minimum recommended intake on average. There is a fiber gap in America. Less than 3 percent meet the recommended minimum. This means that less than 3 percent of all Americans eat enough whole plant foods, the only place fiber is found in abundance. If even half of the adult population ate 3 more grams a day--a quarter cup of beans or a bowl of oatmeal--we could potentially save billions in medical costs. And that's just for constipation! The consumption of plant foods, of fiber-containing foods, may reduce the risk for diabetes, heart disease, stroke, cancer, and obesity as well.

The first to make this link between fiber intake and killer disease was probably Dr. Hugh Trowell. He spent 30 years practicing medicine in Africa and suspected it was the Africans high consumption of corn, millet, sweet potatoes, greens, and beans that protected them from chronic disease. This twisted into the so-called "fiber hypothesis," but Trowell didn't think it was the fiber itself, but the high-fiber foods themselves that were protective. There are hundreds of different substances in whole plant foods besides fiber that may have beneficial effects. For example, the fiber in oatmeal can lower our blood cholesterol levels so that less gets stuck in our arteries, but there also are anti-inflammatory and antioxidant phytonutrients in oats that can prevent atherosclerotic build-up and then help maintain arterial function (see Can Oatmeal Reverse Heart Disease?).

Visionaries like Trowell were not entrapped by the reductionist "simple-minded" focus on dietary fiber and insisted that the whole plant foods should receive the emphasis. Fiber intake was just a marker for plant food intake. Those with the highest fiber intake and the lowest cholesterol were those whose who ate exclusively plant-based diets.

Risk factors like cholesterol are one thing, but can these individual foods actually affect the progression of heart disease, the #1 killer of Americans? We didn't know until 2005. Hundreds of older women were subjected to coronary angiograms, where we inject dye into the coronary arteries of the heart to see how wide open they are. Each participant got an angiogram at the beginning of the study and one a few years later, all while researchers analyzed their diets. The arteries of women eating less than a serving of whole grains a day significantly narrowed, whereas the arteries of women who ate just a single serving or more also significantly narrowed, but they narrowed less. These were all women with heart disease eating the standard American diet, so their arteries were progressively clogging shut. But there was significantly less clogging in the women eating more whole grains, significantly less progression of their atherosclerosis. A similar slowing of their disease might be expected from taking cholesterol-lowering statin drugs. But do we want to just slow the rate at which we die from heart disease, or do we want to not die from heart disease at all?

A strictly plant-based diet has been shown to reverse the progression of heart disease, opening up arteries back up. Yes, whole grains, like drugs, can help counter the artery-clogging effects of the rest of the diet. Having oatmeal with bacon and eggs is better than just eating bacon and eggs, but why not stop eating an artery-clogging diet altogether?

Oatmeal offers a lot more than fiber, though. See Oatmeal Lotion for Chemotherapy-Induced Rash and Can Oatmeal Help Fatty Liver Disease?

Trowell's work had a big influence on Dr. Denis Burkitt. See Dr. Burkitt's F-Word Diet.

This reminds me of other interventions like hibiscus tea for high blood pressure (Hibiscus Tea vs. Plant-Based Diets for Hypertension) or amla for diabetes (Amla Versus Diabetes). Better to reverse the disease completely.

And for an overview of how whole plant foods affect disease risks, be sure to check out the videos on our new Introduction page!

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: Rachel Hathaway / Flickr. This 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

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

What Happened to the Rice Diet?

What Happened to the Rice Diet?.jpeg

During his career at Duke, Dr. Walter Kempner treated more than 18,000 patients with his rice diet. The diet was originally designed as a treatment for kidney failure and out-of-control high blood pressure at a time when these diagnoses were essentially a death sentence. Patients who would have died in all other hospitals had a reasonable chance for survival if they came under Kempner's care.

The results were so dramatic that many experienced physicians suspected him of falsifying data, because he was essentially reversing terminal diseases with rice and fruit, diseases understood to be incurable by the best of modern medicine at the time. Intensive investigations into his clinic vindicated his work, however, which other researchers were then able to replicate and validate.

Kempner was criticized for his lack of controls, meaning that when patients came to him he didn't randomly allocate half to his rice treatment and put the other half on conventional therapy. Kempner argued that the patients each acted as their own controls. For example, one patient, after the medical profession threw everything they had at him, still had blood pressure as high as 220 over 160. A normal blood pressure is considered to be around 120 over 80--which is where Kempner's rice diet took him. Had the patient not been given the rice diet, his pressures might have been even lower, though: zero over zero, because he'd likely be dead. The "control group" in Kempner's day had a survival expectancy estimated at 6 months. To randomize patients to conventional care would be to randomize them to their deaths.

We can also compare those who stuck to the diet to those who didn't. In one study, of those who started the rice diet but then stopped it within a year, 80% died. For those who made it a year but then gave up the diet, instead of an 80% chance of dying, they had about a 50% chance, a flip of the coin. Of those that stuck with the program, 90% lived to tell the tale.

Beginning in the late 1950's, drugs became available that effectively reduced blood pressure and hypertension, leading to a decreased demand for the rice diet. What conclusions can we draw from this all-but-forgotten therapy for hypertension? Not only was it the first effective therapy for high blood pressure, it may be equal to or more effective than our current multi-drug treatments. See Drugs & the Demise of the Rice Diet.

This causes one to speculate on the current practice of placing patients on one drug, then another, and perhaps a third until the blood pressure is controlled, with lip-service advocacy of a moderate reduction in dietary sodium, fat, and protein intake. At the same time, the impressive effectiveness of the rice-fruit diet, which is able to quickly stop the leakage from our arteries, lower increased intracranial pressure, reduce heart size, reverse the ECG changes, reverse heart failure, reduce weight, and markedly improve diabetes, is ignored.

Should we return to the Kempner protocol of starting with the most effective therapy, saving drugs for patients who fail to respond or who are unable or unwilling to restrict their diet? Today many people follow a plant-based diet as a choice, which is similar to what Kempner was often able to transition people to. After their high blood pressure was cured by the rice diet, patients were often able to gradually transition to a less strenuous dietary regime without adding medications and with no return of the elevated blood pressure.

If the Kempner sequence of a strictest of strict plant-based diets to a saner plant-based type diet offers the quickest and best approach to effective therapy, why isn't it still in greater use? The powerful role of the pharmaceutical industry in steering medical care away from dietary treatment to medications should be noted. Who profits from dietary treatment? Who provides the support for investigation and the funds for clinical trials? There is more to overcome than just the patient's reluctance to change their diet.

What Kempner wrote to a patient in 1954 is as true now as it was 60 years ago:

"[D]rugs can be very useful if properly employed and used in conjunction with intensive dietary treatment. However, the real difficulty is that Hypertensive Vascular Disease with all its possible complications--heart disease, kidney disease, stroke, blindness--is still treated very casually, a striking contrast to the attitude toward cancer. Since patients, physicians, and the chemical industry prefer the taking, prescribing, and selling of drugs to a treatment inconvenient to patient and physician and of no benefit to the pharmaceutical industry, the mortality figures for these diseases are still rather appalling."

Despite hundreds of drugs on the market now, high blood pressure remains the #1 cause of death and disability in the world, killing off 9 million people a year. A whole food plant-based diet treats the underlying cause. As Dr. Kempner explained to a patient, "If you should find a heap of manure on your living room floor, I do not recommend that you go buy some Air-Wick [an air freshener] and perfume. I recommend that you get a bucket and shovel and a strong scrubbing brush. Then, when your living room floor is clean again, why, you may certainly apply some Air-Wick if you wish."

As the great physician Maimonides said about 800 years ago, any illness that can be treated by diet alone should be treated by no other means.

For background on this amazing story, see Kempner Rice Diet: Whipping Us Into Shape. He would be proud that there is a whole medical specialty now: Lifestyle Medicine: Treating the Causes of Disease.

This reminds me of the role statin cholesterol-lowering drugs have played in seducing people into the magic bullet approach, but as with all magic it appears to mostly be misdirection:

Check out a couple of my recent overview videos for more on this topic: How Not to Die from Heart Disease and Taking Personal Responsibility for Your Health.

In this day and age, What Diet Should Physician's Recommend?

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

What Happened to the Rice Diet?

What Happened to the Rice Diet?.jpeg

During his career at Duke, Dr. Walter Kempner treated more than 18,000 patients with his rice diet. The diet was originally designed as a treatment for kidney failure and out-of-control high blood pressure at a time when these diagnoses were essentially a death sentence. Patients who would have died in all other hospitals had a reasonable chance for survival if they came under Kempner's care.

The results were so dramatic that many experienced physicians suspected him of falsifying data, because he was essentially reversing terminal diseases with rice and fruit, diseases understood to be incurable by the best of modern medicine at the time. Intensive investigations into his clinic vindicated his work, however, which other researchers were then able to replicate and validate.

Kempner was criticized for his lack of controls, meaning that when patients came to him he didn't randomly allocate half to his rice treatment and put the other half on conventional therapy. Kempner argued that the patients each acted as their own controls. For example, one patient, after the medical profession threw everything they had at him, still had blood pressure as high as 220 over 160. A normal blood pressure is considered to be around 120 over 80--which is where Kempner's rice diet took him. Had the patient not been given the rice diet, his pressures might have been even lower, though: zero over zero, because he'd likely be dead. The "control group" in Kempner's day had a survival expectancy estimated at 6 months. To randomize patients to conventional care would be to randomize them to their deaths.

We can also compare those who stuck to the diet to those who didn't. In one study, of those who started the rice diet but then stopped it within a year, 80% died. For those who made it a year but then gave up the diet, instead of an 80% chance of dying, they had about a 50% chance, a flip of the coin. Of those that stuck with the program, 90% lived to tell the tale.

Beginning in the late 1950's, drugs became available that effectively reduced blood pressure and hypertension, leading to a decreased demand for the rice diet. What conclusions can we draw from this all-but-forgotten therapy for hypertension? Not only was it the first effective therapy for high blood pressure, it may be equal to or more effective than our current multi-drug treatments. See Drugs & the Demise of the Rice Diet.

This causes one to speculate on the current practice of placing patients on one drug, then another, and perhaps a third until the blood pressure is controlled, with lip-service advocacy of a moderate reduction in dietary sodium, fat, and protein intake. At the same time, the impressive effectiveness of the rice-fruit diet, which is able to quickly stop the leakage from our arteries, lower increased intracranial pressure, reduce heart size, reverse the ECG changes, reverse heart failure, reduce weight, and markedly improve diabetes, is ignored.

Should we return to the Kempner protocol of starting with the most effective therapy, saving drugs for patients who fail to respond or who are unable or unwilling to restrict their diet? Today many people follow a plant-based diet as a choice, which is similar to what Kempner was often able to transition people to. After their high blood pressure was cured by the rice diet, patients were often able to gradually transition to a less strenuous dietary regime without adding medications and with no return of the elevated blood pressure.

If the Kempner sequence of a strictest of strict plant-based diets to a saner plant-based type diet offers the quickest and best approach to effective therapy, why isn't it still in greater use? The powerful role of the pharmaceutical industry in steering medical care away from dietary treatment to medications should be noted. Who profits from dietary treatment? Who provides the support for investigation and the funds for clinical trials? There is more to overcome than just the patient's reluctance to change their diet.

What Kempner wrote to a patient in 1954 is as true now as it was 60 years ago:

"[D]rugs can be very useful if properly employed and used in conjunction with intensive dietary treatment. However, the real difficulty is that Hypertensive Vascular Disease with all its possible complications--heart disease, kidney disease, stroke, blindness--is still treated very casually, a striking contrast to the attitude toward cancer. Since patients, physicians, and the chemical industry prefer the taking, prescribing, and selling of drugs to a treatment inconvenient to patient and physician and of no benefit to the pharmaceutical industry, the mortality figures for these diseases are still rather appalling."

Despite hundreds of drugs on the market now, high blood pressure remains the #1 cause of death and disability in the world, killing off 9 million people a year. A whole food plant-based diet treats the underlying cause. As Dr. Kempner explained to a patient, "If you should find a heap of manure on your living room floor, I do not recommend that you go buy some Air-Wick [an air freshener] and perfume. I recommend that you get a bucket and shovel and a strong scrubbing brush. Then, when your living room floor is clean again, why, you may certainly apply some Air-Wick if you wish."

As the great physician Maimonides said about 800 years ago, any illness that can be treated by diet alone should be treated by no other means.

For background on this amazing story, see Kempner Rice Diet: Whipping Us Into Shape. He would be proud that there is a whole medical specialty now: Lifestyle Medicine: Treating the Causes of Disease.

This reminds me of the role statin cholesterol-lowering drugs have played in seducing people into the magic bullet approach, but as with all magic it appears to mostly be misdirection:

Check out a couple of my recent overview videos for more on this topic: How Not to Die from Heart Disease and Taking Personal Responsibility for Your Health.

In this day and age, What Diet Should Physician's Recommend?

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