The 3 Vitamins that Prevent Brain Loss

The 3 Vitamins that Prevent Brain Loss.jpeg

By our seventies, one in five of us will suffer from cognitive impairment. Within five years, half of those cognitively impaired will progress to dementia and death. The earlier we can slow or stop this process, the better.

Although an effective treatment for Alzheimer's disease is unavailable, interventions just to control risk factors could prevent millions of cases. An immense effort has been spent on identifying such risk factors for Alzheimer's and developing treatments to reduce them.

In 1990, a small study of 22 Alzheimer's patients reported high concentrations of homocysteine in their blood. The homocysteine story goes back to 1969 when a Harvard pathologist reported two cases of children, one dating back to 1933, whose brains had turned to mush. They both suffered from extremely rare genetic mutations that led to abnormally high levels of homocysteine in their bodies. Is it possible, he asked, that homocysteine could cause brain damage even in people without genetic defects?

Here we are in the 21st century, and homocysteine is considered "a strong, independent risk factor for the development of dementia and Alzheimer's disease." Having a blood level over 14 (µmol/L) may double our risk. In the Framingham Study, researchers estimate that as many as one in six Alzheimer's cases may be attributable to elevated homocysteine in the blood, which is now thought to play a role in brain damage and cognitive and memory decline. Our body can detoxify homocysteine, though, using three vitamins: folate, vitamin B12, and vitamin B6. So why don't we put them to the test? No matter how many studies find an association between high homocysteinea and cognitive decline, dementia, or Alzheimer's disease, a cause-and-effect role can only be confirmed by interventional studies.

Initially, the results were disappointing. Vitamin supplementation did not seem to work, but the studies were tracking neuropsychological assessments, which are more subjective compared to structural neuroimaging--that is, actually seeing what's happening to the brain. A double-blind randomized controlled trial found that homocysteine-lowering by B vitamins can slow the rate of accelerated brain atrophy in people with mild cognitive impairment. As we age, our brains slowly atrophy, but the shrinking is much accelerated in patients suffering from Alzheimer's disease. An intermediate rate of shrinkage is found in people with mild cognitive impairment. The thinking is if we could slow the rate of brain loss, we may be able to slow the conversion to Alzheimer's disease. Researchers tried giving people B vitamins for two years and found it markedly slowed the rate of brain shrinkage. The rate of atrophy in those with high homocysteine levels was cut in half. A simple, safe treatment can slow the accelerated rate of brain loss.

A follow-up study went further by demonstrating that B-vitamin treatment reduces, by as much as seven-fold, the brain atrophy in the regions specifically vulnerable to the Alzheimer's disease process. You can see the amount of brain atrophy over a two-year period in the placebo group versus the B-vitamin group in my Preventing Brain Loss with B Vitamins? video.

The beneficial effect of B vitamins was confined to those with high homocysteine, indicating a relative deficiency in one of those three vitamins. Wouldn't it be better to not become deficient in the first place? Most people get enough B12 and B6. The reason these folks were stuck at a homocysteine of 11 µmoles per liter is that they probably weren't getting enough folate, which is found concentrated in beans and greens. Ninety-six percent of Americans don't even make the minimum recommended amount of dark green leafy vegetables, which is the same pitiful number who don't eat the minimum recommendation for beans.

If we put people on a healthy diet--a plant-based diet--we can drop their homocysteine levels by 20% in just one week, from around 11 mmoles per liter down to 9 mmoles per liter. The fact that they showed rapid and significant homocysteine lowering without any pills or supplements implies that multiple mechanisms may have been at work. The researchers suggest it may be because of the fiber. Every gram of daily fiber consumption may increase folate levels in the blood nearly 2%, perhaps by boosting vitamin production in the colon by all our friendly gut bacteria. It also could be from the decreased methionine intake.

Methionine is where homocysteine comes from. Homocysteine is a breakdown product of methionine, which comes mostly from animal protein. If we give someone bacon and eggs for breakfast and a steak for dinner, we can get spikes of homocysteine levels in the blood. Thus, decreased methionine intake on a plant-based diet may be another factor contributing to lower, safer homocysteine levels.

The irony is that those who eat plant-based diets long-term, not just at a health spa for a week, have terrible homocysteine levels. Meat-eaters are up at 11 µmoles per liter, but vegetarians at nearly 14 µmoles per liter and vegans at 16 µmoles per liter. Why? The vegetarians and vegans were getting more fiber and folate, but not enough vitamin B12. Most vegans were at risk for suffering from hyperhomocysteinaemia (too much homocysteine in the blood) because most vegans in the study were not supplementing with vitamin B12 or eating vitamin B12-fortified foods, which is critical for anyone eating a plant-based diet. If you take vegans and give them B12, their homocysteine levels can drop down below 5. Why not down to just 11? The reason meat-eaters were stuck up at 11 is presumably because they weren't getting enough folate. Once vegans got enough B12, they could finally fully exploit the benefits of their plant-based diets and come out with the lowest levels of all.

This is very similar to the findings in my video Vitamin B12 Necessary for Arterial Health.

For more details on ensuring a regular reliable source of vitamin B12:

There are more benefits to lowering your methionine intake. Check out Methionine Restriction as a Life Extension Strategy and Starving Cancer with Methionine Restriction.

For more on brain health in general, see these videos:

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: Thomas Hawk / Flickr. This image has been modified.

Original Link

The 3 Vitamins that Prevent Brain Loss

The 3 Vitamins that Prevent Brain Loss.jpeg

By our seventies, one in five of us will suffer from cognitive impairment. Within five years, half of those cognitively impaired will progress to dementia and death. The earlier we can slow or stop this process, the better.

Although an effective treatment for Alzheimer's disease is unavailable, interventions just to control risk factors could prevent millions of cases. An immense effort has been spent on identifying such risk factors for Alzheimer's and developing treatments to reduce them.

In 1990, a small study of 22 Alzheimer's patients reported high concentrations of homocysteine in their blood. The homocysteine story goes back to 1969 when a Harvard pathologist reported two cases of children, one dating back to 1933, whose brains had turned to mush. They both suffered from extremely rare genetic mutations that led to abnormally high levels of homocysteine in their bodies. Is it possible, he asked, that homocysteine could cause brain damage even in people without genetic defects?

Here we are in the 21st century, and homocysteine is considered "a strong, independent risk factor for the development of dementia and Alzheimer's disease." Having a blood level over 14 (µmol/L) may double our risk. In the Framingham Study, researchers estimate that as many as one in six Alzheimer's cases may be attributable to elevated homocysteine in the blood, which is now thought to play a role in brain damage and cognitive and memory decline. Our body can detoxify homocysteine, though, using three vitamins: folate, vitamin B12, and vitamin B6. So why don't we put them to the test? No matter how many studies find an association between high homocysteinea and cognitive decline, dementia, or Alzheimer's disease, a cause-and-effect role can only be confirmed by interventional studies.

Initially, the results were disappointing. Vitamin supplementation did not seem to work, but the studies were tracking neuropsychological assessments, which are more subjective compared to structural neuroimaging--that is, actually seeing what's happening to the brain. A double-blind randomized controlled trial found that homocysteine-lowering by B vitamins can slow the rate of accelerated brain atrophy in people with mild cognitive impairment. As we age, our brains slowly atrophy, but the shrinking is much accelerated in patients suffering from Alzheimer's disease. An intermediate rate of shrinkage is found in people with mild cognitive impairment. The thinking is if we could slow the rate of brain loss, we may be able to slow the conversion to Alzheimer's disease. Researchers tried giving people B vitamins for two years and found it markedly slowed the rate of brain shrinkage. The rate of atrophy in those with high homocysteine levels was cut in half. A simple, safe treatment can slow the accelerated rate of brain loss.

A follow-up study went further by demonstrating that B-vitamin treatment reduces, by as much as seven-fold, the brain atrophy in the regions specifically vulnerable to the Alzheimer's disease process. You can see the amount of brain atrophy over a two-year period in the placebo group versus the B-vitamin group in my Preventing Brain Loss with B Vitamins? video.

The beneficial effect of B vitamins was confined to those with high homocysteine, indicating a relative deficiency in one of those three vitamins. Wouldn't it be better to not become deficient in the first place? Most people get enough B12 and B6. The reason these folks were stuck at a homocysteine of 11 µmoles per liter is that they probably weren't getting enough folate, which is found concentrated in beans and greens. Ninety-six percent of Americans don't even make the minimum recommended amount of dark green leafy vegetables, which is the same pitiful number who don't eat the minimum recommendation for beans.

If we put people on a healthy diet--a plant-based diet--we can drop their homocysteine levels by 20% in just one week, from around 11 mmoles per liter down to 9 mmoles per liter. The fact that they showed rapid and significant homocysteine lowering without any pills or supplements implies that multiple mechanisms may have been at work. The researchers suggest it may be because of the fiber. Every gram of daily fiber consumption may increase folate levels in the blood nearly 2%, perhaps by boosting vitamin production in the colon by all our friendly gut bacteria. It also could be from the decreased methionine intake.

Methionine is where homocysteine comes from. Homocysteine is a breakdown product of methionine, which comes mostly from animal protein. If we give someone bacon and eggs for breakfast and a steak for dinner, we can get spikes of homocysteine levels in the blood. Thus, decreased methionine intake on a plant-based diet may be another factor contributing to lower, safer homocysteine levels.

The irony is that those who eat plant-based diets long-term, not just at a health spa for a week, have terrible homocysteine levels. Meat-eaters are up at 11 µmoles per liter, but vegetarians at nearly 14 µmoles per liter and vegans at 16 µmoles per liter. Why? The vegetarians and vegans were getting more fiber and folate, but not enough vitamin B12. Most vegans were at risk for suffering from hyperhomocysteinaemia (too much homocysteine in the blood) because most vegans in the study were not supplementing with vitamin B12 or eating vitamin B12-fortified foods, which is critical for anyone eating a plant-based diet. If you take vegans and give them B12, their homocysteine levels can drop down below 5. Why not down to just 11? The reason meat-eaters were stuck up at 11 is presumably because they weren't getting enough folate. Once vegans got enough B12, they could finally fully exploit the benefits of their plant-based diets and come out with the lowest levels of all.

This is very similar to the findings in my video Vitamin B12 Necessary for Arterial Health.

For more details on ensuring a regular reliable source of vitamin B12:

There are more benefits to lowering your methionine intake. Check out Methionine Restriction as a Life Extension Strategy and Starving Cancer with Methionine Restriction.

For more on brain health in general, see these videos:

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: Thomas Hawk / Flickr. This image has been modified.

Original Link

Reversing Diabetic Blindness with Diet

Reversing Diabetic Blindness with Diet.jpeg

Though many reported feeling better on Dr. Walter Kempner's rice and fruit diet, he refused to accept such anecdotal evidence as proof of success. He wanted objective measurements. The most famous were his "eyegrounds photographs," taken with a special camera that allowed one to visualize the back of the eye. In doing so, he proved diet can arrest the bleeding, oozing, and swelling you see in the back of the eye in people with severe kidney, hypertensive, or heart disease. Even more than that, he proved that diet could actually reverse it, something never thought possible.

In my video, Can Diabetic Retinopathy Be Reversed?, you can see before and after images of the back of patients' eyes. He found reversal to such a degree that even those who could no longer distinguish large objects were able to once again read fine print. Dr. Kempner had shown a reversal of blindness with diet.

The results were so dramatic that the head of the department of ophthalmology at Duke, where Kempner worked, was questioned as to whether they were somehow faked. He assured them they were not. In fact, he wrote in one person's chart, "This patient's eyegrounds are improved to an unbelievable degree." Not only had he never seen anything like it, he couldn't remember ever seeing a patient with such advanced disease even being alive 15 months later.

The magnitude of the improvements Kempner got--reversal of end-stage heart and kidney failure--was surprising, simply beyond belief. But as Kempner said as his closing sentence of a presentation before the American College of Physicians, "The important result is not that the change in the course of the disease has been achieved by the rice diet but that the course of the disease can be changed."

Now that we have high blood pressure drugs, we see less hypertensive retinopathy, but we still see a lot of diabetic retinopathy, now the leading cause of blindness in American adults. Even with intensive diabetes treatment--at least three insulin injections a day with the best modern technology has to offer--the best we can offer is usually just a slowing of the progression of the disease.

So, in the 21st century, we slow down your blindness. Yet a half century ago, Kempner proved we could reverse it. Kempner started out using his plant-based rice diet ultra-low in sodium, fat, cholesterol, and protein to reverse kidney and heart failure; he actually assumed the diet would make diabetes worse. He expected a 90% carbohydrate diet would increase insulin requirements, however, the opposite proved to be true. He took the next 100 patients with diabetes who walked through his door who went on the rice diet for at least three months and found their fasting blood sugars dropped despite a drop in the insulin they were taking. What really blew people away was this: Forty-four of the patients had diabetic retinopathy, and, in 30% of the cases, their eyes improved. That's not supposed to happen; diabetic retinopathy had been considered "a sign of irreversible destruction." What does this change mean in real life? Patients went from unable to even read headlines to normal vision.

The remarkable success Dr. Kempner had reversing some of the most dreaded complications of diabetes with his rice and fruit diet was not because of weight loss. The improvements occurred even in those patients who did not lose significant weight, so it must have been something specific about the diet. Maybe it was his total elimination of animal protein, animal fat, and cholesterol? Or perhaps it was his radical reduction in sodium, fat, and protein in general? We don't know.

How do we treat diabetic retinopathy these days? With steroids and other drugs injected straight into the eyeball. If that doesn't work, there's always pan-retinal laser photocoagulation, in which laser burns are etched over nearly the entire retina. Surgeons literally burn out the back of your eye. Why would they do that? The theory is that by killing off most of the retina, the little pieces you leave behind may get more blood flow.

When I see that, along with Kempner's work, I can't help but feel like history has been reversed. It seems as though it should have gone like, "Can you believe 50 years ago the best we had was this barbaric, burn-out-your-socket surgery? Thank goodness we've since learned that through dietary means alone, we can reverse the blindness." But instead of learning, medicine seems to have forgotten.

I documented the extraordinary Kempner story previously in Kempner Rice Diet: Whipping Us Into Shape and Drugs and the Demise of the Rice Diet. The reason I keep coming back to this is not to suggest people should go on such a diet (it is too extreme and potentially dangerous to do without strict medical supervision), but to show the power of dietary change to yield tremendous healing effects.

The best way to prevent diabetic blindness is to prevent or reverse diabetes in the first place. See, for example:

Why wouldn't a diet of white rice make diabetes worse? See If White Rice Is Linked to Diabetes, What About China?

For more on the nitty gritty on what is the actual cause of type 2 diabetes, see:

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: Community Eye Health / Flickr. This image has been modified.

Original Link

Reversing Diabetic Blindness with Diet

Reversing Diabetic Blindness with Diet.jpeg

Though many reported feeling better on Dr. Walter Kempner's rice and fruit diet, he refused to accept such anecdotal evidence as proof of success. He wanted objective measurements. The most famous were his "eyegrounds photographs," taken with a special camera that allowed one to visualize the back of the eye. In doing so, he proved diet can arrest the bleeding, oozing, and swelling you see in the back of the eye in people with severe kidney, hypertensive, or heart disease. Even more than that, he proved that diet could actually reverse it, something never thought possible.

In my video, Can Diabetic Retinopathy Be Reversed?, you can see before and after images of the back of patients' eyes. He found reversal to such a degree that even those who could no longer distinguish large objects were able to once again read fine print. Dr. Kempner had shown a reversal of blindness with diet.

The results were so dramatic that the head of the department of ophthalmology at Duke, where Kempner worked, was questioned as to whether they were somehow faked. He assured them they were not. In fact, he wrote in one person's chart, "This patient's eyegrounds are improved to an unbelievable degree." Not only had he never seen anything like it, he couldn't remember ever seeing a patient with such advanced disease even being alive 15 months later.

The magnitude of the improvements Kempner got--reversal of end-stage heart and kidney failure--was surprising, simply beyond belief. But as Kempner said as his closing sentence of a presentation before the American College of Physicians, "The important result is not that the change in the course of the disease has been achieved by the rice diet but that the course of the disease can be changed."

Now that we have high blood pressure drugs, we see less hypertensive retinopathy, but we still see a lot of diabetic retinopathy, now the leading cause of blindness in American adults. Even with intensive diabetes treatment--at least three insulin injections a day with the best modern technology has to offer--the best we can offer is usually just a slowing of the progression of the disease.

So, in the 21st century, we slow down your blindness. Yet a half century ago, Kempner proved we could reverse it. Kempner started out using his plant-based rice diet ultra-low in sodium, fat, cholesterol, and protein to reverse kidney and heart failure; he actually assumed the diet would make diabetes worse. He expected a 90% carbohydrate diet would increase insulin requirements, however, the opposite proved to be true. He took the next 100 patients with diabetes who walked through his door who went on the rice diet for at least three months and found their fasting blood sugars dropped despite a drop in the insulin they were taking. What really blew people away was this: Forty-four of the patients had diabetic retinopathy, and, in 30% of the cases, their eyes improved. That's not supposed to happen; diabetic retinopathy had been considered "a sign of irreversible destruction." What does this change mean in real life? Patients went from unable to even read headlines to normal vision.

The remarkable success Dr. Kempner had reversing some of the most dreaded complications of diabetes with his rice and fruit diet was not because of weight loss. The improvements occurred even in those patients who did not lose significant weight, so it must have been something specific about the diet. Maybe it was his total elimination of animal protein, animal fat, and cholesterol? Or perhaps it was his radical reduction in sodium, fat, and protein in general? We don't know.

How do we treat diabetic retinopathy these days? With steroids and other drugs injected straight into the eyeball. If that doesn't work, there's always pan-retinal laser photocoagulation, in which laser burns are etched over nearly the entire retina. Surgeons literally burn out the back of your eye. Why would they do that? The theory is that by killing off most of the retina, the little pieces you leave behind may get more blood flow.

When I see that, along with Kempner's work, I can't help but feel like history has been reversed. It seems as though it should have gone like, "Can you believe 50 years ago the best we had was this barbaric, burn-out-your-socket surgery? Thank goodness we've since learned that through dietary means alone, we can reverse the blindness." But instead of learning, medicine seems to have forgotten.

I documented the extraordinary Kempner story previously in Kempner Rice Diet: Whipping Us Into Shape and Drugs and the Demise of the Rice Diet. The reason I keep coming back to this is not to suggest people should go on such a diet (it is too extreme and potentially dangerous to do without strict medical supervision), but to show the power of dietary change to yield tremendous healing effects.

The best way to prevent diabetic blindness is to prevent or reverse diabetes in the first place. See, for example:

Why wouldn't a diet of white rice make diabetes worse? See If White Rice Is Linked to Diabetes, What About China?

For more on the nitty gritty on what is the actual cause of type 2 diabetes, see:

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: Community Eye Health / 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

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

Treating Kidney Stones with Diet

Treating Kidney Stones with Diet.jpeg

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

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

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

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

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

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

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

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

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

In health,

Michael Greger, M.D.

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

Image Credit: Sally Plank

Original Link

Treating Kidney Stones with Diet

Treating Kidney Stones with Diet.jpeg

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

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

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

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

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

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

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

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

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

In health,

Michael Greger, M.D.

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

Image Credit: Sally Plank

Original Link

Best Foods for Acid Reflux

Best Foods for Acid Reflux.jpeg

Gastroesophageal reflux disease (GERD) is one of the most common disorders of the digestive tract. The two most typical symptoms are heartburn and regurgitation of stomach contents into the back of the throat, but GERD is not just burning pain and a sour taste in your mouth. It causes millions of doctor visits and hospitalizations every year in the United States. The most feared complication is cancer.

You start out with a normal esophagus. If the acid keeps creeping up, your esophagus can get inflamed and result in esophagitis. Esophagitis can transform into Barrett's esophagus, a precancerous condition which can then turn into adenocarcinoma (a type of cancer). To prevent all that, we need to prevent the acid reflux in the first place.

In the last three decades, the incidence of this cancer in the US has increased six-fold, an increase greater than that of melanoma, breast, or prostate cancer. This is because acid reflux is on the rise. In the United States, we're up to about 1 in 4 people suffering at least weekly heartburn and/or acid regurgitation, compared to around 5% in Asia. This suggests that dietary factors may play a role.

In general, high fat intake is associated with increased risk, whereas high fiber foods appear to be protective. The reason fat intake may be associated with GERD symptoms and erosive esophagitis is because when we eat fatty foods, the sphincter at the top of the stomach that's supposed to keep the food down becomes relaxed, so more acid can creep up into the esophagus. In my video Diet & GERD Acid Reflux Heartburn, you can see a study in which researchers fed volunteers a high-fat meal--a McDonald's sausage and egg McMuffin--compared to a low-fat meal (McDonald's hot cakes), and there was significantly more acid squirted up in the esophagus after the high-fat meal.

In terms of later stages of disease progression, over the last twenty years 45 studies have been published in the association between diet and Barrett's esophagus and esophageal cancer. In general, they found that meat and high-fat meals appeared to increase cancer risk. Different meats were associated with cancers in different locations, thoughj. Red meat was more associated with cancer in the esophagus, whereas poultry was more associated with cancer at the top of the stomach. Plant-based sources of protein, such as beans and nuts, were associated with a significantly decreased risk of cancer.

Those eating the most antioxidant-rich foods have half the odds of esophageal cancer, while there is practically no reduction in risk among those who used antioxidant vitamin supplements, such as vitamin C or E pills. The most protective produce may be red-orange vegetables, dark green leafies, berries, apples, and citrus. The benefit may come from more than just eating plants. Eating healthy foods crowds out less healthy foods, so it may be a combination of both.

Based on a study of 3,000 people, the consumption of non-vegetarian foods (including eggs) was an independent predictor of GERD. Egg yolks cause an increase in the hormone cholecystokinin, which may overly relax the sphincter that separates the esophagus from the stomach. The same hormone is increased by meat, which may help explain why plant-based diets appear to be a protective factor for reflux esophagitis.

Researchers found that those eating meat had twice the odds of reflux-induced esophageal inflammation. Therefore, plant-based diets may offer protection, though it's uncertain whether it's attributable to the absence of meat in the diet or the increased consumption of healthy foods. Those eating vegetarian consume greater amounts of fruits and vegetables containing innumerable phytochemicals, dietary fiber, and antioxidants. They also restrict their consumption of animal sources of food, which tend to be fattier and can thus relax that sphincter and aggravate reflux.

GERD is common; its burdens are enormous. It relapses frequently and can cause bleeding, strictures, and a deadly cancer. The mainstay of treatment is proton pump inhibitor drugs, which rake in billions of dollars. We spend four billion dollars on Nexium alone, three billion on Prevacid, two billion on Protonix, one billion on Aciphex. These drugs can cause nutrient deficiencies and increase the risk for pneumonia, food poisoning, and bone fractures. Thus, it is important to find correctable risk factors and correct them. Known correctable risk factors have been things like obesity, smoking and alcohol consumption. Until recently, though, there hadn't been studies on specifically what to eat and what to avoid, but now we have other correctable factors to help prevent this disease.

For more on GERD, see: Diet & Hiatal Hernia, Coffee & Mortality, and Club Soda for Stomach Pain & Constipation.

I also have a video about esophageal cancer, detailing the extraordinary reversal of the kinds of precancerous changes that lead to the devastating condition--with nothing but strawberries: Strawberries versus Esophageal Cancer.

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: PDPics / Pixabay. Image has been modified.

Original Link

Best Foods for Acid Reflux

Best Foods for Acid Reflux.jpeg

Gastroesophageal reflux disease (GERD) is one of the most common disorders of the digestive tract. The two most typical symptoms are heartburn and regurgitation of stomach contents into the back of the throat, but GERD is not just burning pain and a sour taste in your mouth. It causes millions of doctor visits and hospitalizations every year in the United States. The most feared complication is cancer.

You start out with a normal esophagus. If the acid keeps creeping up, your esophagus can get inflamed and result in esophagitis. Esophagitis can transform into Barrett's esophagus, a precancerous condition which can then turn into adenocarcinoma (a type of cancer). To prevent all that, we need to prevent the acid reflux in the first place.

In the last three decades, the incidence of this cancer in the US has increased six-fold, an increase greater than that of melanoma, breast, or prostate cancer. This is because acid reflux is on the rise. In the United States, we're up to about 1 in 4 people suffering at least weekly heartburn and/or acid regurgitation, compared to around 5% in Asia. This suggests that dietary factors may play a role.

In general, high fat intake is associated with increased risk, whereas high fiber foods appear to be protective. The reason fat intake may be associated with GERD symptoms and erosive esophagitis is because when we eat fatty foods, the sphincter at the top of the stomach that's supposed to keep the food down becomes relaxed, so more acid can creep up into the esophagus. In my video Diet & GERD Acid Reflux Heartburn, you can see a study in which researchers fed volunteers a high-fat meal--a McDonald's sausage and egg McMuffin--compared to a low-fat meal (McDonald's hot cakes), and there was significantly more acid squirted up in the esophagus after the high-fat meal.

In terms of later stages of disease progression, over the last twenty years 45 studies have been published in the association between diet and Barrett's esophagus and esophageal cancer. In general, they found that meat and high-fat meals appeared to increase cancer risk. Different meats were associated with cancers in different locations, thoughj. Red meat was more associated with cancer in the esophagus, whereas poultry was more associated with cancer at the top of the stomach. Plant-based sources of protein, such as beans and nuts, were associated with a significantly decreased risk of cancer.

Those eating the most antioxidant-rich foods have half the odds of esophageal cancer, while there is practically no reduction in risk among those who used antioxidant vitamin supplements, such as vitamin C or E pills. The most protective produce may be red-orange vegetables, dark green leafies, berries, apples, and citrus. The benefit may come from more than just eating plants. Eating healthy foods crowds out less healthy foods, so it may be a combination of both.

Based on a study of 3,000 people, the consumption of non-vegetarian foods (including eggs) was an independent predictor of GERD. Egg yolks cause an increase in the hormone cholecystokinin, which may overly relax the sphincter that separates the esophagus from the stomach. The same hormone is increased by meat, which may help explain why plant-based diets appear to be a protective factor for reflux esophagitis.

Researchers found that those eating meat had twice the odds of reflux-induced esophageal inflammation. Therefore, plant-based diets may offer protection, though it's uncertain whether it's attributable to the absence of meat in the diet or the increased consumption of healthy foods. Those eating vegetarian consume greater amounts of fruits and vegetables containing innumerable phytochemicals, dietary fiber, and antioxidants. They also restrict their consumption of animal sources of food, which tend to be fattier and can thus relax that sphincter and aggravate reflux.

GERD is common; its burdens are enormous. It relapses frequently and can cause bleeding, strictures, and a deadly cancer. The mainstay of treatment is proton pump inhibitor drugs, which rake in billions of dollars. We spend four billion dollars on Nexium alone, three billion on Prevacid, two billion on Protonix, one billion on Aciphex. These drugs can cause nutrient deficiencies and increase the risk for pneumonia, food poisoning, and bone fractures. Thus, it is important to find correctable risk factors and correct them. Known correctable risk factors have been things like obesity, smoking and alcohol consumption. Until recently, though, there hadn't been studies on specifically what to eat and what to avoid, but now we have other correctable factors to help prevent this disease.

For more on GERD, see: Diet & Hiatal Hernia, Coffee & Mortality, and Club Soda for Stomach Pain & Constipation.

I also have a video about esophageal cancer, detailing the extraordinary reversal of the kinds of precancerous changes that lead to the devastating condition--with nothing but strawberries: Strawberries versus Esophageal Cancer.

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: PDPics / Pixabay. Image has been modified.

Original Link