What Animal Protein Does in Your Colon

What Animal Protein Does in Your Colon.jpeg

There's a take-off of the industry slogan, "Beef: It's What's For Dinner" - "Beef: It's What's Rotting in Your Colon." I saw this on a shirt once with some friends and I was such the party pooper--no pun intended--explaining to everyone that meat is fully digested in the small intestine, and never makes it down into the colon. It's no fun hanging out with biology geeks.

But I was wrong!

It's been estimated that with a typical Western diet, up to 12 grams of protein can escape digestion, and when it reaches the colon, it can be turned into toxic substances like ammonia. This degradation of undigested protein in the colon is called putrefaction, so a little meat can actually end up putrefying in our colon. The problem is that some of the by-products of this putrefaction process can be toxic.

It's generally accepted that carbohydrate fermentation--the fiber and resistant starches that reach our colon--results in beneficial effects because of the generation of short-chain fatty acids like butyrate, whereas protein fermentation is considered detrimental. Protein fermentation mainly occurs in the lower end of colon and results in the production of potentially toxic metabolites. That may be why colorectal cancer and ulcerative colitis tends to happen lower down--because that's where the protein is putrefying.

Probably the simplest strategy to reduce the potential harm of protein fermentation is to reduce dietary protein intake. But the accumulation of these toxic byproducts of protein metabolism may be attenuated by the fermentation of undigested plant matter. In my video, Bowel Wars: Hydrogen Sulfide vs. Butyrate, you can see a study out of Australia showed that if you give people foods containing resistant starch you can block the accumulation of potentially harmful byproducts of protein metabolism. Resistant starch is resistant to small intestine digestion and so it makes it down to our colon where it can feed our good bacteria. Resistant starch is found in cooked beans, split peas, chickpeas, lentils, raw oatmeal, and cooled cooked pasta (like macaroni salad). Apparently, the more starch that ends up in the colon, the less ammonia that is produced.

Of course, there's protein in plants too. The difference is that animal proteins tend to have more sulfur-containing amino acids like methionine, which can be turned into hydrogen sulfide in our colon. Hydrogen sulfide is the rotten egg gas that may play a role in the development of the inflammatory bowel disease, ulcerative colitis (see Preventing Ulcerative Colitis with Diet).

The toxic effects of hydrogen sulfide appear to be a result of blocking the ability of the cells lining our colon from utilizing butyrate, which is what our good bacteria make from the fiber and resistant starch we eat. It's like this constant battle in our colon between the bad metabolites of protein, hydrogen sulfide, and the good metabolites of carbohydrates, butyrate. Using human colon samples, researchers were able to show that the adverse effects of sulfide could be reversed by butyrate. So we can either cut down on meat, eat more plants, or both.

There are two ways hydrogen sulfide can be produced, though. It's mainly present in our large intestine as a result of the breakdown of sulfur-containing proteins, but the rotten egg gas can also be generated from inorganic sulfur preservatives like sulfites and sulfur dioxide.

Sulfur dioxide is used as a preservative in dried fruit, and sulfites are added to wines. We can avoid sulfur additives by reading labels or by just choosing organic, since they're forbidden from organic fruits and beverages by law.

More than 35 years ago, studies started implicating sulfur dioxide preservatives in the exacerbation of asthma. This so-called "sulfite-sensitivity" seems to affect only about 1 in 2,000 people, so I recommended those with asthma avoid it, but otherwise I considered the preservative harmless. I am now not so sure, and advise people to avoid it when possible.

Cabbage family vegetables naturally have some sulfur compounds, but thankfully, after following more than a hundred thousand women for over 25 years, researchers concluded cruciferous vegetables were not associated with elevated colitis risk.

Because of animal protein and processed food intake, the standard American diet may contain five or six times more sulfur than a diet centered around unprocessed plant foods. This may help explain the rarity of inflammatory bowel disease among those eating traditional whole food, plant-based diets.

How could companies just add things like sulfur dioxide to foods without adequate safety testing? See Who Determines if Food Additives are Safe? For other additives that may be a problem, see Titanium Dioxide & Inflammatory Bowel Disease and Is Carrageenan Safe?

More on this epic fermentation battle in our gut in Stool pH and Colon Cancer.

Does the sulfur-containing amino acid methionine sound familiar? You may remember it from such hits as Starving Cancer with Methionine Restriction and Methionine Restriction as a Life Extension Strategy.

These short-chain fatty acids released by our good bacteria when we eat fiber and resistant starches are what may be behind the second meal effect: Beans and the Second Meal Effect.

I mentioned ulcerative colitis. What about the other inflammatory bowel disease Crohn's? See Preventing Crohn's Disease With Diet and Dietary Treatment of Crohn's Disease.

In health,

Michael Greger, M.D.

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

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

Original Link

What Animal Protein Does in Your Colon

What Animal Protein Does in Your Colon.jpeg

There's a take-off of the industry slogan, "Beef: It's What's For Dinner" - "Beef: It's What's Rotting in Your Colon." I saw this on a shirt once with some friends and I was such the party pooper--no pun intended--explaining to everyone that meat is fully digested in the small intestine, and never makes it down into the colon. It's no fun hanging out with biology geeks.

But I was wrong!

It's been estimated that with a typical Western diet, up to 12 grams of protein can escape digestion, and when it reaches the colon, it can be turned into toxic substances like ammonia. This degradation of undigested protein in the colon is called putrefaction, so a little meat can actually end up putrefying in our colon. The problem is that some of the by-products of this putrefaction process can be toxic.

It's generally accepted that carbohydrate fermentation--the fiber and resistant starches that reach our colon--results in beneficial effects because of the generation of short-chain fatty acids like butyrate, whereas protein fermentation is considered detrimental. Protein fermentation mainly occurs in the lower end of colon and results in the production of potentially toxic metabolites. That may be why colorectal cancer and ulcerative colitis tends to happen lower down--because that's where the protein is putrefying.

Probably the simplest strategy to reduce the potential harm of protein fermentation is to reduce dietary protein intake. But the accumulation of these toxic byproducts of protein metabolism may be attenuated by the fermentation of undigested plant matter. In my video, Bowel Wars: Hydrogen Sulfide vs. Butyrate, you can see a study out of Australia showed that if you give people foods containing resistant starch you can block the accumulation of potentially harmful byproducts of protein metabolism. Resistant starch is resistant to small intestine digestion and so it makes it down to our colon where it can feed our good bacteria. Resistant starch is found in cooked beans, split peas, chickpeas, lentils, raw oatmeal, and cooled cooked pasta (like macaroni salad). Apparently, the more starch that ends up in the colon, the less ammonia that is produced.

Of course, there's protein in plants too. The difference is that animal proteins tend to have more sulfur-containing amino acids like methionine, which can be turned into hydrogen sulfide in our colon. Hydrogen sulfide is the rotten egg gas that may play a role in the development of the inflammatory bowel disease, ulcerative colitis (see Preventing Ulcerative Colitis with Diet).

The toxic effects of hydrogen sulfide appear to be a result of blocking the ability of the cells lining our colon from utilizing butyrate, which is what our good bacteria make from the fiber and resistant starch we eat. It's like this constant battle in our colon between the bad metabolites of protein, hydrogen sulfide, and the good metabolites of carbohydrates, butyrate. Using human colon samples, researchers were able to show that the adverse effects of sulfide could be reversed by butyrate. So we can either cut down on meat, eat more plants, or both.

There are two ways hydrogen sulfide can be produced, though. It's mainly present in our large intestine as a result of the breakdown of sulfur-containing proteins, but the rotten egg gas can also be generated from inorganic sulfur preservatives like sulfites and sulfur dioxide.

Sulfur dioxide is used as a preservative in dried fruit, and sulfites are added to wines. We can avoid sulfur additives by reading labels or by just choosing organic, since they're forbidden from organic fruits and beverages by law.

More than 35 years ago, studies started implicating sulfur dioxide preservatives in the exacerbation of asthma. This so-called "sulfite-sensitivity" seems to affect only about 1 in 2,000 people, so I recommended those with asthma avoid it, but otherwise I considered the preservative harmless. I am now not so sure, and advise people to avoid it when possible.

Cabbage family vegetables naturally have some sulfur compounds, but thankfully, after following more than a hundred thousand women for over 25 years, researchers concluded cruciferous vegetables were not associated with elevated colitis risk.

Because of animal protein and processed food intake, the standard American diet may contain five or six times more sulfur than a diet centered around unprocessed plant foods. This may help explain the rarity of inflammatory bowel disease among those eating traditional whole food, plant-based diets.

How could companies just add things like sulfur dioxide to foods without adequate safety testing? See Who Determines if Food Additives are Safe? For other additives that may be a problem, see Titanium Dioxide & Inflammatory Bowel Disease and Is Carrageenan Safe?

More on this epic fermentation battle in our gut in Stool pH and Colon Cancer.

Does the sulfur-containing amino acid methionine sound familiar? You may remember it from such hits as Starving Cancer with Methionine Restriction and Methionine Restriction as a Life Extension Strategy.

These short-chain fatty acids released by our good bacteria when we eat fiber and resistant starches are what may be behind the second meal effect: Beans and the Second Meal Effect.

I mentioned ulcerative colitis. What about the other inflammatory bowel disease Crohn's? See Preventing Crohn's Disease With Diet and Dietary Treatment of Crohn's Disease.

In health,

Michael Greger, M.D.

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

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

Original Link

White Meat May Be as Cholesterol-Raising as Red

White Meat May Be as Cholesterol-Raising as Red.jpeg

In light of recommendations for heart healthy eating from national professional organizations encouraging Americans to limit their intake of meat, the beef industry commissioned and co-wrote a review of randomized controlled trials comparing the effects of beef versus chicken and fish on cholesterol levels published over the last 60 years. They found that the impact of beef consumption on the cholesterol profile of humans is similar to that of fish and/or poultry--meaning that switching from red meat to white meat likely wouldn't make any difference. And that's really no surprise, given how fat we've genetically manipulated chickens to be these days, up to ten times more fat than they had a century ago (see Does Eating Obesity Cause Obesity?).

There are a number of cuts of beef that have less cholesterol-raising saturated fat than chicken (see BOLD Indeed: Beef Lowers Cholesterol?), so it's not so surprising that white meat was found to be no better than red, but the beef industry researchers conclusion was that "therefore you can eat beef as part of a balanced diet to manage your cholesterol."

Think of the Coke versus Pepsi analogy. Coke has less sugar than Pepsi: 15 spoonfuls of sugar per bottle instead of 16. If studies on blood sugar found no difference between drinking Coke versus Pepsi, you wouldn't conclude that "Pepsi may be considered when recommending diets for the management of blood sugars," you'd say they're both equally as bad so we should ideally consume neither.

That's a standard drug industry trick. You don't compare your fancy new drug to the best out there, but to some miserable drug to make yours look better. Note they didn't compare beef to plant proteins, like in this study published in the American Journal of Clinical Nutrition. As I started reading it, though, I was surprised that they found no benefit of switching to a plant protein diet either. What were they eating? You can see the comparison in Switching from Beef to Chicken & Fish May Not Lower Cholesterol.

For breakfast, the plant group got a kidney bean and tomato casserole and a salad, instead of a burger. And for dinner, instead of another burger, the plant protein group just got some boring vegetables. So why was the cholesterol of the plant group as bad as the animal group? They had the plant protein group eating three tablespoons of beef tallow every day--three tablespoons of straight beef fat!

This was part of a series of studies that tried to figure out what was so cholesterol-raising about meat--was it the animal protein or was it the animal fat? So, researchers created fake meat products made to have the same amount of saturated fat and cholesterol by adding extracted animal fats and cholesterol. Who could they get to make such strange concoctions? The Ralston Purina dog food company.

But what's crazy is that even when keeping the saturated animal fat and cholesterol the same (by adding meat fats to the veggie burgers and making the plant group swallow cholesterol pills to equal it out), sometimes they still saw a cholesterol lowering advantage in the plant protein group.

If you switch people from meat to tofu, their cholesterol goes down, but what if you switch them from meat to tofu plus lard? Then their cholesterol may stay the same, though tofu and lard may indeed actually be better than meat, since it may result in less oxidized cholesterol. More on the role of oxidized cholesterol can be found in my videos Does Cholesterol Size Matter? and Arterial Acne.

Just swapping plant protein for animal protein may have advantages, but if you really want to maximize the power of diet to lower cholesterol, you may have to move entirely toward plants. The standard dietary advice to cut down on fatty meat, dairy, and eggs may lower cholesterol 5-10%, but flexitarian or vegetarian diets may drop our levels 10 to 15%, vegan diets 15 to 25%, and healthier vegan diets can cut up to 35%, as seen in this study out of Canada showing a whopping 61 point drop in LDL cholesterol within a matter of weeks.


You thought chicken was a low-fat food? It used to be a century ago, but not anymore. It may even be one of the reasons we're getting fatter as well: Chicken Big: Poultry and Obesity and Infectobesity: Adenovirus 36 and Childhood Obesity.

Isn't protein just protein? How does our body know if it's coming from a plant or an animal? How could it have different effects on cardiovascular risk? See Protein and Heart Disease, another reason why Plant Protein [is] Preferable.

Lowering cholesterol in your blood is as simple as reducing one's intake of three things: Trans Fat, Saturated Fat, and Cholesterol: Tolerable Upper Intake of Zero.

What about those news stories on the "vindication" of saturated fat? See the sneaky science in The Saturated Fat Studies: Buttering Up the Public and The Saturated Fat Studies: Set Up to Fail.

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: CDC/Debora Cartagena via Freestockphotos.biz. This image has been modified.

Original Link

White Meat May Be as Cholesterol-Raising as Red

White Meat May Be as Cholesterol-Raising as Red.jpeg

In light of recommendations for heart healthy eating from national professional organizations encouraging Americans to limit their intake of meat, the beef industry commissioned and co-wrote a review of randomized controlled trials comparing the effects of beef versus chicken and fish on cholesterol levels published over the last 60 years. They found that the impact of beef consumption on the cholesterol profile of humans is similar to that of fish and/or poultry--meaning that switching from red meat to white meat likely wouldn't make any difference. And that's really no surprise, given how fat we've genetically manipulated chickens to be these days, up to ten times more fat than they had a century ago (see Does Eating Obesity Cause Obesity?).

There are a number of cuts of beef that have less cholesterol-raising saturated fat than chicken (see BOLD Indeed: Beef Lowers Cholesterol?), so it's not so surprising that white meat was found to be no better than red, but the beef industry researchers conclusion was that "therefore you can eat beef as part of a balanced diet to manage your cholesterol."

Think of the Coke versus Pepsi analogy. Coke has less sugar than Pepsi: 15 spoonfuls of sugar per bottle instead of 16. If studies on blood sugar found no difference between drinking Coke versus Pepsi, you wouldn't conclude that "Pepsi may be considered when recommending diets for the management of blood sugars," you'd say they're both equally as bad so we should ideally consume neither.

That's a standard drug industry trick. You don't compare your fancy new drug to the best out there, but to some miserable drug to make yours look better. Note they didn't compare beef to plant proteins, like in this study published in the American Journal of Clinical Nutrition. As I started reading it, though, I was surprised that they found no benefit of switching to a plant protein diet either. What were they eating? You can see the comparison in Switching from Beef to Chicken & Fish May Not Lower Cholesterol.

For breakfast, the plant group got a kidney bean and tomato casserole and a salad, instead of a burger. And for dinner, instead of another burger, the plant protein group just got some boring vegetables. So why was the cholesterol of the plant group as bad as the animal group? They had the plant protein group eating three tablespoons of beef tallow every day--three tablespoons of straight beef fat!

This was part of a series of studies that tried to figure out what was so cholesterol-raising about meat--was it the animal protein or was it the animal fat? So, researchers created fake meat products made to have the same amount of saturated fat and cholesterol by adding extracted animal fats and cholesterol. Who could they get to make such strange concoctions? The Ralston Purina dog food company.

But what's crazy is that even when keeping the saturated animal fat and cholesterol the same (by adding meat fats to the veggie burgers and making the plant group swallow cholesterol pills to equal it out), sometimes they still saw a cholesterol lowering advantage in the plant protein group.

If you switch people from meat to tofu, their cholesterol goes down, but what if you switch them from meat to tofu plus lard? Then their cholesterol may stay the same, though tofu and lard may indeed actually be better than meat, since it may result in less oxidized cholesterol. More on the role of oxidized cholesterol can be found in my videos Does Cholesterol Size Matter? and Arterial Acne.

Just swapping plant protein for animal protein may have advantages, but if you really want to maximize the power of diet to lower cholesterol, you may have to move entirely toward plants. The standard dietary advice to cut down on fatty meat, dairy, and eggs may lower cholesterol 5-10%, but flexitarian or vegetarian diets may drop our levels 10 to 15%, vegan diets 15 to 25%, and healthier vegan diets can cut up to 35%, as seen in this study out of Canada showing a whopping 61 point drop in LDL cholesterol within a matter of weeks.


You thought chicken was a low-fat food? It used to be a century ago, but not anymore. It may even be one of the reasons we're getting fatter as well: Chicken Big: Poultry and Obesity and Infectobesity: Adenovirus 36 and Childhood Obesity.

Isn't protein just protein? How does our body know if it's coming from a plant or an animal? How could it have different effects on cardiovascular risk? See Protein and Heart Disease, another reason why Plant Protein [is] Preferable.

Lowering cholesterol in your blood is as simple as reducing one's intake of three things: Trans Fat, Saturated Fat, and Cholesterol: Tolerable Upper Intake of Zero.

What about those news stories on the "vindication" of saturated fat? See the sneaky science in The Saturated Fat Studies: Buttering Up the Public and The Saturated Fat Studies: Set Up to Fail.

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: CDC/Debora Cartagena via Freestockphotos.biz. This image has been modified.

Original Link

What Not to Add to White Rice, Potatoes, or Pasta

What Not to Add to White Rice, Potatoes, or Pasta.jpeg

Rice currently feeds almost half the human population, making it the single most important staple food in the world, but a meta-analysis of seven cohort studies following 350,000 people for up to 20 years found that higher consumption of white rice was associated with a significantly increased risk of type 2 diabetes, especially in Asian populations. They estimated each serving per day of white rice was associated with an 11% increase in risk of diabetes. This could explain why China has almost the same diabetes rates as we do.

Diabetes rates in China are at about 10%; we're at about 11%, despite seven times less obesity in China. Japan has eight times less obesity than we do, yet may have a higher incidence of newly diagnosed diabetes cases than we do--nine per a thousand compared to our eight. They're skinnier and still may have more diabetes. Maybe it's because of all the white rice they eat.

Eating whole fruit is associated with lower risk of diabetes, whereas eating fruit processed into juice may not just be neutral, but actually increases diabetes risk. In the same way, eating whole grains, like whole wheat bread or brown rice is associated with lower risk of diabetes, whereas eating white rice, a processed grain, may not just be neutral, but actually increase diabetes risk.

White rice consumption does not appear to be associated with increased risk of heart attack or stroke, though, which is a relief after an earlier study in China suggested a connection with stroke. But do we want to eat a food that's just neutral regarding some of our leading causes of death, when we can eat whole foods that are associated with lower risk of diabetes, heart attack, stroke, and weight gain?

If the modern diabetes epidemic in China and Japan has been linked to white rice consumption, how can we reconcile that with low diabetes rates just a few decades ago when they ate even more rice? If you look at the Cornell-Oxford-China Project, rural plant-based diets centered around rice were associated with relatively low risk of the so-called diseases of affluence, which includes diabetes. Maybe Asians just genetically don't get the same blood sugar spike when they eat white rice? This is not the case; if anything people of Chinese ethnicity get higher blood sugar spikes.

The rise in these diseases of affluence in China over the last half century has been blamed in part on the tripling of the consumption of animal source foods. The upsurge in diabetes has been most dramatic, and it's mostly just happened over the last decade. That crazy 9.7% diabetes prevalence figure that rivals ours is new--they appeared to have one of the lowest diabetes rates in the world in the year 2000.

So what happened to their diets in the last 20 years or so? Oil consumption went up 20%, pork consumption went up 40%, and rice consumption dropped about 30%. As diabetes rates were skyrocketing, rice consumption was going down, so maybe it's the animal products and junk food that are the problem. Yes, brown rice is better than white rice, but to stop the mounting Asian epidemic, maybe we should focus on removing the cause--the toxic Western diet. That would be consistent with data showing animal protein and fat consumption associated with increased diabetes risk.

But that doesn't explain why the biggest recent studies in Japan and China associate white rice intake with diabetes. One possibility is that animal protein is making the rice worse. If you feed people mashed white potatoes, a high glycemic food like white rice, you can see in my video If White Rice is Linked to Diabetes, What About China? the level of insulin your pancreas has to pump out to keep your blood sugars in check. But what if you added some tuna fish? Tuna doesn't have any carbs, sugar, or starch so it shouldn't make a difference. Or maybe it would even lower the mashed potato spike by lowering the glycemic load of the whole meal? Instead you get twice the insulin spike. This also happens with white flour spaghetti versus white flour spaghetti with meat. The addition of animal protein makes the pancreas work twice as hard.

You can do it with straight sugar water too. If you do a glucose challenge test to test for diabetes, where you drink a certain amount of sugar and add some meat, you get a much bigger spike than without meat. And the more meat you add, the worse it gets. Just adding a little meat to carbs doesn't seem to do much, but once you get up to around a third of a chicken breast's worth, you can elicit a significantly increased surge of insulin. This may help explain why those eating plant-based have such low diabetes rates, because animal protein can markedly potentiate the insulin secretion triggered by carbohydrate ingestion.

The protein exacerbation of the effect of refined carbs could help explain the remarkable results achieved by Dr. Kempner with a don't-try-this-at-home diet composed of mostly white rice and sugar. See my video, Kempner Rice Diet: Whipping Us Into Shape.

Refined grains may also not be good for our blood pressure (see Whole Grains May Work As Well As Drugs).

What should we be eating to best decrease our risk of diabetes? See:

And check out my summary video, How Not to Die from Diabetes.

In health,
Michael Greger, M.D.

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

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

Original Link

What Not to Add to White Rice, Potatoes, or Pasta

What Not to Add to White Rice, Potatoes, or Pasta.jpeg

Rice currently feeds almost half the human population, making it the single most important staple food in the world, but a meta-analysis of seven cohort studies following 350,000 people for up to 20 years found that higher consumption of white rice was associated with a significantly increased risk of type 2 diabetes, especially in Asian populations. They estimated each serving per day of white rice was associated with an 11% increase in risk of diabetes. This could explain why China has almost the same diabetes rates as we do.

Diabetes rates in China are at about 10%; we're at about 11%, despite seven times less obesity in China. Japan has eight times less obesity than we do, yet may have a higher incidence of newly diagnosed diabetes cases than we do--nine per a thousand compared to our eight. They're skinnier and still may have more diabetes. Maybe it's because of all the white rice they eat.

Eating whole fruit is associated with lower risk of diabetes, whereas eating fruit processed into juice may not just be neutral, but actually increases diabetes risk. In the same way, eating whole grains, like whole wheat bread or brown rice is associated with lower risk of diabetes, whereas eating white rice, a processed grain, may not just be neutral, but actually increase diabetes risk.

White rice consumption does not appear to be associated with increased risk of heart attack or stroke, though, which is a relief after an earlier study in China suggested a connection with stroke. But do we want to eat a food that's just neutral regarding some of our leading causes of death, when we can eat whole foods that are associated with lower risk of diabetes, heart attack, stroke, and weight gain?

If the modern diabetes epidemic in China and Japan has been linked to white rice consumption, how can we reconcile that with low diabetes rates just a few decades ago when they ate even more rice? If you look at the Cornell-Oxford-China Project, rural plant-based diets centered around rice were associated with relatively low risk of the so-called diseases of affluence, which includes diabetes. Maybe Asians just genetically don't get the same blood sugar spike when they eat white rice? This is not the case; if anything people of Chinese ethnicity get higher blood sugar spikes.

The rise in these diseases of affluence in China over the last half century has been blamed in part on the tripling of the consumption of animal source foods. The upsurge in diabetes has been most dramatic, and it's mostly just happened over the last decade. That crazy 9.7% diabetes prevalence figure that rivals ours is new--they appeared to have one of the lowest diabetes rates in the world in the year 2000.

So what happened to their diets in the last 20 years or so? Oil consumption went up 20%, pork consumption went up 40%, and rice consumption dropped about 30%. As diabetes rates were skyrocketing, rice consumption was going down, so maybe it's the animal products and junk food that are the problem. Yes, brown rice is better than white rice, but to stop the mounting Asian epidemic, maybe we should focus on removing the cause--the toxic Western diet. That would be consistent with data showing animal protein and fat consumption associated with increased diabetes risk.

But that doesn't explain why the biggest recent studies in Japan and China associate white rice intake with diabetes. One possibility is that animal protein is making the rice worse. If you feed people mashed white potatoes, a high glycemic food like white rice, you can see in my video If White Rice is Linked to Diabetes, What About China? the level of insulin your pancreas has to pump out to keep your blood sugars in check. But what if you added some tuna fish? Tuna doesn't have any carbs, sugar, or starch so it shouldn't make a difference. Or maybe it would even lower the mashed potato spike by lowering the glycemic load of the whole meal? Instead you get twice the insulin spike. This also happens with white flour spaghetti versus white flour spaghetti with meat. The addition of animal protein makes the pancreas work twice as hard.

You can do it with straight sugar water too. If you do a glucose challenge test to test for diabetes, where you drink a certain amount of sugar and add some meat, you get a much bigger spike than without meat. And the more meat you add, the worse it gets. Just adding a little meat to carbs doesn't seem to do much, but once you get up to around a third of a chicken breast's worth, you can elicit a significantly increased surge of insulin. This may help explain why those eating plant-based have such low diabetes rates, because animal protein can markedly potentiate the insulin secretion triggered by carbohydrate ingestion.

The protein exacerbation of the effect of refined carbs could help explain the remarkable results achieved by Dr. Kempner with a don't-try-this-at-home diet composed of mostly white rice and sugar. See my video, Kempner Rice Diet: Whipping Us Into Shape.

Refined grains may also not be good for our blood pressure (see Whole Grains May Work As Well As Drugs).

What should we be eating to best decrease our risk of diabetes? See:

And check out my summary video, How Not to Die from Diabetes.

In health,
Michael Greger, M.D.

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

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

Original Link

Striving for Alkaline Pee and Acidic Poo

Stool pH and Colon Cancer.jpg

More than 30 years ago, an idea was put forward that high colonic pH promoted colorectal cancer. A high colonic pH may promote the creation of carcinogens from bile acids, a process that is inhibited once you get below a pH of about 6.5. This is supported by data which shows those at higher risk for colon cancer may have a higher stool pH, and those at lower risk have a low pH. There was a dramatic difference between the two groups, with most of the high risk group over pH 8, and most of the low risk group under pH 6 (see Stool pH and Colon Cancer).

This may help explain the 50-fold lower rates of colon cancer in Africa compared to America. The bacteria we have in our gut depends on what we eat. If we eat lots of fiber, then we preferentially feed the fiber eating bacteria, which give us back all sorts of health promoting substances like short-chain fatty acids that have anti-inflammatory and anti-cancer properties. More of these organic acids were found in the stools of native Africans than African Americans. More acids, so lower pH. Whereas putrefactive bacteria, eating animal protein, are able to increase stool pH by producing alkaline metabolites like ammonia.

The pH of the stools of white versus black children in Africa was compared. Children were chosen because you can more readily sample their stools, particularly the rural black schoolchildren who were eating such high fiber diets--whole grains, legumes, nuts, vegetables, fruits, and wild greens--that 90% of them could produce a stool on demand. Stuffed from head to tail with plants, they could give you a stool sample at any time, just as easy as getting a urine sample. It was hard to even get access to the white kids, though, who were reluctant to participate in such investigations, even though they were given waxed cartons fitted with lids while all the black kids got was a plate and a square of paper towel.

The researchers found significantly lower fecal pH in those eating the traditional, rural plant-based diets compared to those eating the traditional Western diet, who were eating far fewer whole plant foods than the black children. But, remove some of those whole plant foods, like switch their corn for white bread for just a few days and their stool pH goes up, and add whole plant foods like an extra five to seven servings of fruit every day, and their stool pH goes down even further and gets more acidic. It makes sense because when you ferment fruits, veggies, and grains, they turn sour, like vinegar, sauerkraut, or sourdough, because good bacteria like lactobacillus produce organic acids like lactic acid. Those who eat a lot of plants have more of those good bugs. So, using the purple cabbage test highlighted in my video, Testing Your Diet with Pee & Purple Cabbage, we want blue pee, but pink poo.

If you compare the fecal samples of those eating vegetarian or vegan to those eating standard diets, plant-based diets appear to shift the makeup of the bacteria in our gut, resulting in a significantly lower stool pH, and the more plant-based, the lower the pH dropped. It's like a positive feedback loop: fiber-eating bacteria produce the acids to create the pH at which fiber-eating bacteria thrive while suppressing the group of less beneficial bugs.

It might taken even as little as two weeks to bring stool pH down on a plant-based diet. In a study published in the British Journal of Cancer, a dozen volunteers carefully selected for their trustworthiness and randomized to sequentially go on regular, vegetarian, or vegan diets and two weeks in, a significant drop in fecal pH was achieved eating completely plant-based.

But there are differing qualities of plant-based diets. For example, the two groups followed in the study I mentioned earlier had dramatically different stool pH, yet both groups were vegetarian. The high risk group was eating mostly refined grains, very little fiber, whereas the low risk group was eating whole grains and beans, packed with fiber for our fiber-friendly flora to munch on.

Just as a "reduction of high serum cholesterol contributes to the avoidance of coronary heart disease," a fall in the fecal pH value may contribute to the avoidance of bowel cancer and through the same means, eating more whole plant foods.

More on colon cancer prevention in:

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: Kitti Sukhonthanit © 123RF.com. This image has been modified.

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Striving for Alkaline Pee and Acidic Poo

Stool pH and Colon Cancer.jpg

More than 30 years ago, an idea was put forward that high colonic pH promoted colorectal cancer. A high colonic pH may promote the creation of carcinogens from bile acids, a process that is inhibited once you get below a pH of about 6.5. This is supported by data which shows those at higher risk for colon cancer may have a higher stool pH, and those at lower risk have a low pH. There was a dramatic difference between the two groups, with most of the high risk group over pH 8, and most of the low risk group under pH 6 (see Stool pH and Colon Cancer).

This may help explain the 50-fold lower rates of colon cancer in Africa compared to America. The bacteria we have in our gut depends on what we eat. If we eat lots of fiber, then we preferentially feed the fiber eating bacteria, which give us back all sorts of health promoting substances like short-chain fatty acids that have anti-inflammatory and anti-cancer properties. More of these organic acids were found in the stools of native Africans than African Americans. More acids, so lower pH. Whereas putrefactive bacteria, eating animal protein, are able to increase stool pH by producing alkaline metabolites like ammonia.

The pH of the stools of white versus black children in Africa was compared. Children were chosen because you can more readily sample their stools, particularly the rural black schoolchildren who were eating such high fiber diets--whole grains, legumes, nuts, vegetables, fruits, and wild greens--that 90% of them could produce a stool on demand. Stuffed from head to tail with plants, they could give you a stool sample at any time, just as easy as getting a urine sample. It was hard to even get access to the white kids, though, who were reluctant to participate in such investigations, even though they were given waxed cartons fitted with lids while all the black kids got was a plate and a square of paper towel.

The researchers found significantly lower fecal pH in those eating the traditional, rural plant-based diets compared to those eating the traditional Western diet, who were eating far fewer whole plant foods than the black children. But, remove some of those whole plant foods, like switch their corn for white bread for just a few days and their stool pH goes up, and add whole plant foods like an extra five to seven servings of fruit every day, and their stool pH goes down even further and gets more acidic. It makes sense because when you ferment fruits, veggies, and grains, they turn sour, like vinegar, sauerkraut, or sourdough, because good bacteria like lactobacillus produce organic acids like lactic acid. Those who eat a lot of plants have more of those good bugs. So, using the purple cabbage test highlighted in my video, Testing Your Diet with Pee & Purple Cabbage, we want blue pee, but pink poo.

If you compare the fecal samples of those eating vegetarian or vegan to those eating standard diets, plant-based diets appear to shift the makeup of the bacteria in our gut, resulting in a significantly lower stool pH, and the more plant-based, the lower the pH dropped. It's like a positive feedback loop: fiber-eating bacteria produce the acids to create the pH at which fiber-eating bacteria thrive while suppressing the group of less beneficial bugs.

It might taken even as little as two weeks to bring stool pH down on a plant-based diet. In a study published in the British Journal of Cancer, a dozen volunteers carefully selected for their trustworthiness and randomized to sequentially go on regular, vegetarian, or vegan diets and two weeks in, a significant drop in fecal pH was achieved eating completely plant-based.

But there are differing qualities of plant-based diets. For example, the two groups followed in the study I mentioned earlier had dramatically different stool pH, yet both groups were vegetarian. The high risk group was eating mostly refined grains, very little fiber, whereas the low risk group was eating whole grains and beans, packed with fiber for our fiber-friendly flora to munch on.

Just as a "reduction of high serum cholesterol contributes to the avoidance of coronary heart disease," a fall in the fecal pH value may contribute to the avoidance of bowel cancer and through the same means, eating more whole plant foods.

More on colon cancer prevention in:

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: Kitti Sukhonthanit © 123RF.com. This image has been modified.

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How to Prevent Ulcerative Colitis with Diet

Preventing Ulcerative Colitis with Diet.jpg

What has driven the dramatic increase in prevalence of the inflammatory bowel disease Crohn's disease in societies that rapidly westernized--a disease practically unknown just a century ago? What has changed in our internal and external environment that has led to the appearance of this horrible disease?

Japan suffered one of the most dramatic increases, and out of all the changing dietary components, animal protein appeared to be the strongest factor. There was an exponential increase in newly diagnosed Crohn's patients and daily animal protein intake, whereas the greater the vegetable protein, the fewer the cases of Crohn's, which is consistent with data showing a more plant-based diet may be successful in both preventing and treating Crohn's disease (See Preventing Crohn's Disease With Diet and Dietary Treatment of Crohn's Disease). But what about other inflammatory bowel diseases?

In the largest study of its kind, shown in my video Preventing Ulcerative Colitis with Diet, 60,000 people were followed for more than a decade. Researchers found that high total protein intake--specifically animal protein--was associated with a significantly increased risk of the other big inflammatory bowel disease, ulcerative colitis. It wasn't just protein in general, but the "association between high protein intake and inflammatory bowel disease risk was restricted to animal protein."Since World War II, animal protein intake has increased not only in Japan but also in all developed countries. This increase in animal protein consumption is thought to explain some of the increased incidence of inflammatory bowel disease in the second half of the 20th century.

Other studies found this as well, but why? What's the difference between animal protein and plant protein? Animal proteins tend to have more sulfur containing amino acids like methionine, which bacteria in our gut can turn into the toxic rotten egg smell gas, hydrogen sulfide. Emerging evidence suggests that sulfur compounds may play a role in the development of ulcerative colitis, a chronic inflammatory disease of the colon and rectum characterized by bloody diarrhea.

The first hint as to the importance of our gut flora was in the 1970's when "analysis of stools showed that their bulk was made up of mostly bacteria, not undigested material." We're pushing out trillions of bacteria a day and they just keep multiplying and multiplying. They do wonderful things for us like create the protective compound, butyrate, from the fiber we eat, but unfortunately, the bacteria may also elaborate toxic products from food residues such as hydrogen sulfide "in response to a high-meat diet."

Hydrogen sulfide is a bacterially derived cell poison that has been implicated in ulcerative colitis. We had always assumed that sulfide generation in the colon is driven by dietary components such as sulfur-containing amino acids, but we didn't know for sure until a study from Cambridge was published. Researchers had folks eat five different diets each with escalating meat contents from vegetarian all the way up to a steak each day. They found that the more meat one ate, the more sulfide; ten times more meat meant ten times more sulfide. They concluded that "dietary protein from meat is an important substrate for sulfide generation by bacteria in the human large intestine."

Hydrogen sulfide can then act as a free radical and damage our DNA at concentrations way below what our poor colon lining is exposed to on a routine basis, which may help explain why diets higher in meat and lower in fiber may produce so-called "fecal water" that causes about twice as much DNA damage. Fecal water is like when researchers make a tea from someone's stool.

The biology of sulfur in the human gut has escaped serious attention until recently. Previously it was just thought of as the rotten egg smell in malodorous gas, but the increase in sulfur compounds in response to a supplement of animal protein is not only of interest in the field of flatology--that is, the formal study of farts--but may also be of importance in the development of ulcerative colitis.

I have several videos on our microbiome, including:

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: illustrator © 123RF.com. This image has been modified.

Original Link

How to Prevent Ulcerative Colitis with Diet

Preventing Ulcerative Colitis with Diet.jpg

What has driven the dramatic increase in prevalence of the inflammatory bowel disease Crohn's disease in societies that rapidly westernized--a disease practically unknown just a century ago? What has changed in our internal and external environment that has led to the appearance of this horrible disease?

Japan suffered one of the most dramatic increases, and out of all the changing dietary components, animal protein appeared to be the strongest factor. There was an exponential increase in newly diagnosed Crohn's patients and daily animal protein intake, whereas the greater the vegetable protein, the fewer the cases of Crohn's, which is consistent with data showing a more plant-based diet may be successful in both preventing and treating Crohn's disease (See Preventing Crohn's Disease With Diet and Dietary Treatment of Crohn's Disease). But what about other inflammatory bowel diseases?

In the largest study of its kind, shown in my video Preventing Ulcerative Colitis with Diet, 60,000 people were followed for more than a decade. Researchers found that high total protein intake--specifically animal protein--was associated with a significantly increased risk of the other big inflammatory bowel disease, ulcerative colitis. It wasn't just protein in general, but the "association between high protein intake and inflammatory bowel disease risk was restricted to animal protein."Since World War II, animal protein intake has increased not only in Japan but also in all developed countries. This increase in animal protein consumption is thought to explain some of the increased incidence of inflammatory bowel disease in the second half of the 20th century.

Other studies found this as well, but why? What's the difference between animal protein and plant protein? Animal proteins tend to have more sulfur containing amino acids like methionine, which bacteria in our gut can turn into the toxic rotten egg smell gas, hydrogen sulfide. Emerging evidence suggests that sulfur compounds may play a role in the development of ulcerative colitis, a chronic inflammatory disease of the colon and rectum characterized by bloody diarrhea.

The first hint as to the importance of our gut flora was in the 1970's when "analysis of stools showed that their bulk was made up of mostly bacteria, not undigested material." We're pushing out trillions of bacteria a day and they just keep multiplying and multiplying. They do wonderful things for us like create the protective compound, butyrate, from the fiber we eat, but unfortunately, the bacteria may also elaborate toxic products from food residues such as hydrogen sulfide "in response to a high-meat diet."

Hydrogen sulfide is a bacterially derived cell poison that has been implicated in ulcerative colitis. We had always assumed that sulfide generation in the colon is driven by dietary components such as sulfur-containing amino acids, but we didn't know for sure until a study from Cambridge was published. Researchers had folks eat five different diets each with escalating meat contents from vegetarian all the way up to a steak each day. They found that the more meat one ate, the more sulfide; ten times more meat meant ten times more sulfide. They concluded that "dietary protein from meat is an important substrate for sulfide generation by bacteria in the human large intestine."

Hydrogen sulfide can then act as a free radical and damage our DNA at concentrations way below what our poor colon lining is exposed to on a routine basis, which may help explain why diets higher in meat and lower in fiber may produce so-called "fecal water" that causes about twice as much DNA damage. Fecal water is like when researchers make a tea from someone's stool.

The biology of sulfur in the human gut has escaped serious attention until recently. Previously it was just thought of as the rotten egg smell in malodorous gas, but the increase in sulfur compounds in response to a supplement of animal protein is not only of interest in the field of flatology--that is, the formal study of farts--but may also be of importance in the development of ulcerative colitis.

I have several videos on our microbiome, including:

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: illustrator © 123RF.com. This image has been modified.

Original Link