What Causes Diabetes?

What Causes Diabetes?.jpeg

After about age 20, we may have all the insulin-producing beta cells we're ever going to get. So if we lose them, we may lose them for good. Autopsy studies show that by the time type 2 diabetes is diagnosed, we may have already killed off half of our beta cells.

You can kill pancreatic cells right in a petri dish. If you expose the insulin-producing beta cells in our pancreas to fat, they suck it up and then start dying off. Fat breakdown products can interfere with the function of these cells and ultimately lead to their death. A chronic increase in blood fat levels can be harmful to our pancreas.

It's not just any fat; it's saturated fat. As you can see in my video, What Causes Diabetes?, predominant fat in olives, nuts, and avocados gives a tiny bump in death protein 5, but saturated fat really elevates this contributor to beta cell death. Therefore, saturated fats are harmful to beta cells. Cholesterol is, too. The uptake of bad cholesterol (LDL) can cause beta cell death as a result of free radical formation.

Diets rich in saturated fats not only cause obesity and insulin resistance, but the increased levels of circulating free fats in the blood (non-esterified fatty acids, or NEFAs) may also cause beta cell death and may thus contribute to the progressive beta cell loss we see in type 2 diabetes. These findings aren't just based on test tube studies. If researchers have infused fat into people's blood streams, they can show it directly impairing pancreatic beta cell function. The same occurs when we ingest it.

Type 2 diabetes is characterized by "defects in both insulin secretion and insulin action," and saturated fat appears to impair both. Researchers showed saturated fat ingestion reduces insulin sensitivity within hours. The subjects were non-diabetics, so their pancreases should have been able to boost insulin secretion to match the drop in sensitivity. But no, "insulin secretion failed to compensate for insulin resistance in subjects who ingested [the saturated fat]." This implies saturated fat impaired beta cell function as well, again just within hours after going into our mouth. "[I]ncreased consumption of [saturated fats] has a powerful short- and long-term effect on insulin action," contributing to the dysfunction and death of pancreatic beta cells in diabetes.

Saturated fat isn't just toxic to the pancreas. The fats found predominantly in meat and dairy--chicken and cheese are the two main sources in the American diet--are considered nearly "universally toxic." In contrast, the fats found in olives, nuts, and avocados are not. Saturated fat has been found to be particularly toxic to liver cells, contributing to the formation of fatty liver disease. If you expose human liver cells to plant fat, though, nothing happens. If you expose our liver cells to animal fat, a third of them die. This may explain why higher intake of saturated fat and cholesterol are associated with non-alcoholic fatty liver disease.

By cutting down on saturated fat consumption, we may be able to help interrupt these processes. Decreasing saturated fat intake can help bring down the need for all that excess insulin. So either being fat or eating saturated fat can both cause excess insulin in the blood. The effect of reducing dietary saturated fat intake on insulin levels is substantial, regardless of how much belly fat we have. It's not just that by eating fat we may be more likely to store it as fat. Saturated fats, independently of any role they have in making us fat, "may contribute to the development of insulin resistance and its clinical consequences." After controlling for weight, alcohol, smoking, exercise, and family history, diabetes incidence was significantly associated with the proportion of saturated fat in our blood.

So what causes diabetes? The consumption of too many calories rich in saturated fats. Just like everyone who smokes doesn't develop lung cancer, everyone who eats a lot of saturated fat doesn't develop diabetes--there is a genetic component. But just like smoking can be said to cause lung cancer, high-calorie diets rich in saturated fats are currently considered the cause of type 2 diabetes.

I have a lot of videos on diabetes, including:

Preventing the disease:

And treating it:

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. This image has been modified.

Original Link

Solving a Colon Cancer Mystery

Solving-a-Colon-Cancer-Mystery.jpeg

Colorectal cancer is the second leading cause of cancer death in the United States, after lung cancer. The rates of lung cancer around the world vary by a factor of 10. If there was nothing we could do to prevent lung cancer--if it just happened at random--we'd assume that the rates everywhere would be about the same. But since there's such a huge variation in rates, it seems like there's probably some external cause. Indeed, we now know smoking is responsible for 90% of lung cancer cases. If we don't want to die of the number-one cancer killer, we can throw 90% of our risk out the window just by not smoking.

There's an even bigger variation around the world for colon cancer. As discussed in Solving a Colon Cancer Mystery, it appears colon cancer doesn't just happen, something makes it happen. If our lungs can get filled with carcinogens from smoke, maybe our colons are getting filled with carcinogens from food. Researchers from the University of Pittsburgh and the University of Limpopo sought to answer the question, "Why do African Americans get more colon cancer than native Africans?" Why study Africans? Because colon cancer is extremely rare in native African populations, more than 50 times lower than rates of Americans, white or black.

It's the fiber, right? The first to describe the low rates of colon cancer in native Africans, Dr. Denis Burkitt ascribed it to their staple diet traditionally high in whole grains and, consequently, high in fiber content. We seem to get a 10% reduction in risk for every 10 grams of fiber we eat a day. If it's a 1% drop for each gram, and native Africans are eating upwards of 100 grams a day, it could explain why colon cancer is so rare in sub-Saharan Africa.

Wait a second. The modern African diet is highly processed and low in fiber, yet there has been no dramatic increase in colon cancer incidence. Their diet today has such a low fiber content because most populations now depend on commercially produced refined cornmeal. We're not just talking low fiber intake, we're talking United States of America low, down around half the recommended daily allowance. Yet colon disease in Africa is still about 50 times less common than in the United States.

Maybe it's because native Africans are thinner and exercise more? No, they're not, and no, they don't. If anything, their physical activity levels may now be even lower than Americans'. So if they're sedentary like us and eating mostly refined carbs, few whole plant foods, and little fiber like us, why do they have 50 times less colon cancer than we do? There is one difference. The diet of both African Americans and Caucasian Americans is rich in meat, whereas the native Africans' diet is so low in meat and saturated fat they have total cholesterol levels averaging 139 mg/dL, compared to over 200 mg/dL in the United States.

They may not get a lot of fiber anymore, but they continue to minimize meat and animal fat consumption, which supports other evidence indicating the most powerful determinants of colon cancer risk may be meat and animal fat intake levels. So why do Americans get more colon cancer than Africans? Maybe the rarity of colon cancer in Africans is not the fiber, but their low animal product consumption.

Although opinions diverge as to whether cholesterol, animal fat, or animal protein is most responsible for the increased colon cancer risk, given that all three have been proven to have carcinogenic properties, it may not really matter which component is worse, as a diet laden in one is usually laden in the others.

I've previously suggested phytates may play a critical role as well (Phytates for the Prevention of Cancer). Resistant starch may be another player. Since native Africans cool down their corn porridge, some of the starch can crystallize and effectively turn into fiber. (This is the same reason pasta salad and potato salad better feed our gut bacteria than starchy dishes served hot.) I touch on it briefly in Bowel Wars: Hydrogen Sulfide vs. Butyrate. Resistant starch may also help explain Beans and the Second Meal Effect. And for even more, see Resistant Starch & Colon Cancer and Getting Starch to Take the Path of Most Resistance.

Fiber may just be a marker for healthier eating since it's only found concentrated in unprocessed plant foods. So the apparent protection afforded by high fiber diets may derive from whole food plant-based nutrition rather than the fiber itself (so fiber supplements would not be expected to provide the same protection). Here are some videos that found protective associations with higher fiber diets:

What might be in animal products that can raise cancer risk? Here's a smattering:

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: Department of Foreign Affairs and Trade / Flickr. This image has been modified.

Original Link

Solving a Colon Cancer Mystery

Solving-a-Colon-Cancer-Mystery.jpeg

Colorectal cancer is the second leading cause of cancer death in the United States, after lung cancer. The rates of lung cancer around the world vary by a factor of 10. If there was nothing we could do to prevent lung cancer--if it just happened at random--we'd assume that the rates everywhere would be about the same. But since there's such a huge variation in rates, it seems like there's probably some external cause. Indeed, we now know smoking is responsible for 90% of lung cancer cases. If we don't want to die of the number-one cancer killer, we can throw 90% of our risk out the window just by not smoking.

There's an even bigger variation around the world for colon cancer. As discussed in Solving a Colon Cancer Mystery, it appears colon cancer doesn't just happen, something makes it happen. If our lungs can get filled with carcinogens from smoke, maybe our colons are getting filled with carcinogens from food. Researchers from the University of Pittsburgh and the University of Limpopo sought to answer the question, "Why do African Americans get more colon cancer than native Africans?" Why study Africans? Because colon cancer is extremely rare in native African populations, more than 50 times lower than rates of Americans, white or black.

It's the fiber, right? The first to describe the low rates of colon cancer in native Africans, Dr. Denis Burkitt ascribed it to their staple diet traditionally high in whole grains and, consequently, high in fiber content. We seem to get a 10% reduction in risk for every 10 grams of fiber we eat a day. If it's a 1% drop for each gram, and native Africans are eating upwards of 100 grams a day, it could explain why colon cancer is so rare in sub-Saharan Africa.

Wait a second. The modern African diet is highly processed and low in fiber, yet there has been no dramatic increase in colon cancer incidence. Their diet today has such a low fiber content because most populations now depend on commercially produced refined cornmeal. We're not just talking low fiber intake, we're talking United States of America low, down around half the recommended daily allowance. Yet colon disease in Africa is still about 50 times less common than in the United States.

Maybe it's because native Africans are thinner and exercise more? No, they're not, and no, they don't. If anything, their physical activity levels may now be even lower than Americans'. So if they're sedentary like us and eating mostly refined carbs, few whole plant foods, and little fiber like us, why do they have 50 times less colon cancer than we do? There is one difference. The diet of both African Americans and Caucasian Americans is rich in meat, whereas the native Africans' diet is so low in meat and saturated fat they have total cholesterol levels averaging 139 mg/dL, compared to over 200 mg/dL in the United States.

They may not get a lot of fiber anymore, but they continue to minimize meat and animal fat consumption, which supports other evidence indicating the most powerful determinants of colon cancer risk may be meat and animal fat intake levels. So why do Americans get more colon cancer than Africans? Maybe the rarity of colon cancer in Africans is not the fiber, but their low animal product consumption.

Although opinions diverge as to whether cholesterol, animal fat, or animal protein is most responsible for the increased colon cancer risk, given that all three have been proven to have carcinogenic properties, it may not really matter which component is worse, as a diet laden in one is usually laden in the others.

I've previously suggested phytates may play a critical role as well (Phytates for the Prevention of Cancer). Resistant starch may be another player. Since native Africans cool down their corn porridge, some of the starch can crystallize and effectively turn into fiber. (This is the same reason pasta salad and potato salad better feed our gut bacteria than starchy dishes served hot.) I touch on it briefly in Bowel Wars: Hydrogen Sulfide vs. Butyrate. Resistant starch may also help explain Beans and the Second Meal Effect. And for even more, see Resistant Starch & Colon Cancer and Getting Starch to Take the Path of Most Resistance.

Fiber may just be a marker for healthier eating since it's only found concentrated in unprocessed plant foods. So the apparent protection afforded by high fiber diets may derive from whole food plant-based nutrition rather than the fiber itself (so fiber supplements would not be expected to provide the same protection). Here are some videos that found protective associations with higher fiber diets:

What might be in animal products that can raise cancer risk? Here's a smattering:

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: Department of Foreign Affairs and Trade / Flickr. This image has been modified.

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

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.

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Can Oatmeal Reverse Heart Disease?

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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.

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High Blood Pressure: Normal but Not Natural

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The most comprehensive and systematic analysis of causes of death ever undertaken allows us to answer questions like, how many lives could we save if people cut back on soda? The answer is 299,521. Soft drinks aren't just bad because they're empty calories. More than just not being a health-promoting item, soda appears to be an actively death-promoting item. Of course, it's not as deadly as processed meats such as bacon, bologna, ham, or hot dogs, which account for about 800,000 deaths every year--killing twice as many women as domestic violence and five times more people than all illegal drugs combined.

On the other hand, eating more whole grains could save 1.7 million lives. And more vegetables could save 1.8 million lives every year. If only we ate more nuts and seeds, we'd save 2 and a half million lives. But fruit is apparently what the world needs most (they didn't look at beans) with 4.9 million lives hanging in the balance every year. The cure is not drugs or vaccines; the cure is fruit. The #1 dietary risk factor for death in the world may be not eating enough fruit.

One reason why plant-based diets can save so many millions is because the #1 killer risk factor in the world is high blood pressure, laying to waste nine million people year after year. In the United States, high blood pressure affects nearly 78 million--that's one in three of us. As we age our pressures get higher and higher, such that by age 60, it strikes more than half of that population. If it affects most of us when we get older, maybe it's less a disease and more just a natural, inevitable consequence of getting older?

No.

We've known for nearly a century that high blood pressure need never occur. Researchers measured the blood pressure of a thousand people in rural Kenya. Up until age 40, the blood pressures of rural Africans were about the same as Europeans and Americans, down around 120's over 80's, but as Westerners age, our pressures creep up such that by age 60 the average person is hypertensive, exceeding 140 over 90. But the pressures of those in rural Africa improved with age; not only did they not develop hypertension, their blood pressures actually got better.

The 140/90 cut-off is arbitrary. Just like studies that show the lower our cholesterol the better--there's really no safe level above about 150--blood pressure studies also support a "lower the better" approach. Even people who start out with blood pressure under 120/80 appear to benefit from blood pressure reduction. The ideal blood pressure, the no-benefit-from-reducing-it-further blood pressure, appears to be 110/70. Is it possible to get blood pressures under 110 over 70? It's not just possible, it can be normal for those eating healthy enough diets (see How Not to Die from High Blood Pressure).

Over two years at a rural Kenyan hospital, 1,800 patients were admitted. How many cases of high blood pressure were found? Zero. Wow. They must have had low rates of heart disease. Actually, they had no rates of heart disease. Not low risk--no risk. Not a single case of arteriosclerosis was found.

Having a "normal" blood pressure may set you up for dying from "normal" causes such as heart attacks and strokes. For more on this concept, see When Low Risk Means High Risk. It's like having a normal cholesterol level (see Optimal Cholesterol Level).

It seems high blood pressure is a choice. Like cavities: Cavities and Coronaries: Our Choice.

Even end-stage malignant hypertension can be reversed with diet (thereby demonstrating it was the diet and not other lifestyle factors that protected traditional plant-based populations). See Kempner Rice Diet: Whipping Us Into Shape.

Flax seeds, hibiscus tea, whole grains, and nitrate-rich vegetables may offer additional protection:

Why not just take the drugs? See The Actual Benefit of Diet vs. Drugs and Why Prevention is Worth a Ton of Cure. And be sure to check out my summary video, How Not to Die from High Blood Pressure, as well as The Evidence that Salt Raises Blood Pressure.

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.

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