How to Treat High Blood Pressure with Diet

How to Treat High Blood Pressure with Diet.jpeg

High blood pressure ranks as the number-one risk factor for death and disability in the world. In my video, How to Prevent High Blood Pressure with Diet, I showed how a plant-based diet may prevent high blood pressure. But what do we do if we already have it? That's the topic of How to Treat High Blood Pressure with Diet.

The American Heart Association, the American College of Cardiology, and the Centers for Disease Control and Prevention recommend lifestyle modification as the first-line treatment. If that doesn't work, patients may be prescribed a thiazide diuretic (commonly known as a water pill) before getting even more meds until their blood pressure is forced down. Commonly, people will end up on three drugs, though researchers are experimenting with four at a time. Some patients even end up on five different meds.

What's wrong with skipping the lifestyle modification step and jumping straight to the drugs? Because drugs don't treat the underlying cause of high blood pressure yet can cause side effects. Less than half of patients stick with even the first-line drugs, perhaps due to such adverse effects as erectile dysfunction, fatigue, and muscle cramps.

What are the recommended lifestyle changes? The AHA, ACC, and CDC recommend controlling one's weight, salt, and alcohol intake, engaging in regular exercise, and adopting a DASH eating plan.

The DASH diet has been described as a lactovegetarian diet, but it's not. It emphasizes fruits, vegetables, and low-fat dairy, but only a reduction in meat consumption. Why not vegetarian? We've known for decades that animal products are significantly associated with blood pressure. In fact, if we take vegetarians and give them meat (and pay them enough to eat it!), we can watch their blood pressures go right up.

I've talked about the benefits to getting blood pressure down as low as 110 over 70. But who can get that low? Populations centering their diets around whole plant foods. Rural Chinese have been recorded with blood pressures averaging around 110 over 70 their whole lives. In rural Africa, the elderly have perfect blood pressure as opposed to hypertension. What both diets share in common is that they're plant-based day-to-day, with meat only eaten on special occasion.

How do we know it's the plant-based nature of their diets that was so protective? Because in the Western world, as the American Heart Association has pointed out, the only folks getting down that low were those eating strictly plant-based diets, coming out about 110 over 65.

So were the creators of the DASH diet just not aware of this landmark research done by Harvard's Frank Sacks? No, they were aware. The Chair of the Design Committee that came up with the DASH diet was Dr. Sacks himself. In fact, the DASH diet was explicitly designed with the number-one goal of capturing the blood pressure-lowering benefits of a vegetarian diet, yet including enough animal products to make it "palatable" to the general public.

You can see what they were thinking. Just like drugs never work--unless you actually take them. Diet never work--unless you actually eat them. So what's the point of telling people to eat strictly plant-based if few people will do it? So by soft-peddling the truth and coming up with a compromise diet you can imagine how they were thinking that on a population clae they might be doing more good. Ok, but tell that to the thousand U.S. families a day that lose a loved one to high blood pressure. Maybe it's time to start telling the American public the truth.

Sacks himself found that the more dairy the lactovegetarians ate, the higher their blood pressures. But they had to make the diet acceptable. Research has since shown that it's the added plant foods--not the changes in oil, sweets, or dairy--that appears to the critical component of the DASH diet. So why not eat a diet composed entirely of plant foods?

A recent meta-analysis showed vegetarian diets are good, but strictly plant-based diets may be better. In general, vegetarian diets provide protection against cardiovascular diseases, some cancers, and even death. But completely plant-based diets seem to offer additional protection against obesity, hypertension, type-2 diabetes, and heart disease mortality. Based on a study of more than 89,000 people, those eating meat-free diets appear to cut their risk of high blood pressure in half. But those eating meat-free, egg-free, and dairy-free may have 75% lower risk.

What if we're already eating a whole food, plant-based diet, no processed foods, no table salt, yet still not hitting 110 over 70? Here are some foods recently found to offer additional protection: Just a few tablespoons of ground flaxseeds a day was 2 to 3 times more potent than instituting an aerobic endurance exercise program and induced one of the most powerful, antihypertensive effects ever achieved by a diet-related intervention. Watermelon also appears to be extraordinary, but you'd have to eat around 2 pounds a day. Sounds like my kind of medicine, but it's hard to get year-round (at least in my neck of the woods). Red wine may help, but only if the alcohol has been taken out. Raw vegetables or cooked? The answer is both, though raw may work better. Beans, split peas, chickpeas, and lentils may also help a bit.

Kiwifruits don't seem to work at all, even though the study was funded by a kiwifruit company. Maybe they should have taken direction from the California Raisin Marketing Board, which came out with a study showing raisins can reduce blood pressure, but only, apparently, compared to fudge cookies, Cheez-Its, and Chips Ahoy.

The DASH diet is one of the best studied, and it consistently ranks as US News & World Report's #1 diet. It's one of the few diets that medical students are taught about in medical school. I was so fascinated to learn of its origins as a compromise between practicality and efficacy.

I've talked about the patronizing attitude many doctors have that patients can't handle the truth in:

What would hearing the truth from your physician sound like? See Fully Consensual Heart Disease Treatment and The Actual Benefit of Diet vs. Drugs.

For more on what plants can do for high blood pressure, 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: Sally Plank. This image has been modified.

Original Link

How to Treat High Blood Pressure with Diet

How to Treat High Blood Pressure with Diet.jpeg

High blood pressure ranks as the number-one risk factor for death and disability in the world. In my video, How to Prevent High Blood Pressure with Diet, I showed how a plant-based diet may prevent high blood pressure. But what do we do if we already have it? That's the topic of How to Treat High Blood Pressure with Diet.

The American Heart Association, the American College of Cardiology, and the Centers for Disease Control and Prevention recommend lifestyle modification as the first-line treatment. If that doesn't work, patients may be prescribed a thiazide diuretic (commonly known as a water pill) before getting even more meds until their blood pressure is forced down. Commonly, people will end up on three drugs, though researchers are experimenting with four at a time. Some patients even end up on five different meds.

What's wrong with skipping the lifestyle modification step and jumping straight to the drugs? Because drugs don't treat the underlying cause of high blood pressure yet can cause side effects. Less than half of patients stick with even the first-line drugs, perhaps due to such adverse effects as erectile dysfunction, fatigue, and muscle cramps.

What are the recommended lifestyle changes? The AHA, ACC, and CDC recommend controlling one's weight, salt, and alcohol intake, engaging in regular exercise, and adopting a DASH eating plan.

The DASH diet has been described as a lactovegetarian diet, but it's not. It emphasizes fruits, vegetables, and low-fat dairy, but only a reduction in meat consumption. Why not vegetarian? We've known for decades that animal products are significantly associated with blood pressure. In fact, if we take vegetarians and give them meat (and pay them enough to eat it!), we can watch their blood pressures go right up.

I've talked about the benefits to getting blood pressure down as low as 110 over 70. But who can get that low? Populations centering their diets around whole plant foods. Rural Chinese have been recorded with blood pressures averaging around 110 over 70 their whole lives. In rural Africa, the elderly have perfect blood pressure as opposed to hypertension. What both diets share in common is that they're plant-based day-to-day, with meat only eaten on special occasion.

How do we know it's the plant-based nature of their diets that was so protective? Because in the Western world, as the American Heart Association has pointed out, the only folks getting down that low were those eating strictly plant-based diets, coming out about 110 over 65.

So were the creators of the DASH diet just not aware of this landmark research done by Harvard's Frank Sacks? No, they were aware. The Chair of the Design Committee that came up with the DASH diet was Dr. Sacks himself. In fact, the DASH diet was explicitly designed with the number-one goal of capturing the blood pressure-lowering benefits of a vegetarian diet, yet including enough animal products to make it "palatable" to the general public.

You can see what they were thinking. Just like drugs never work--unless you actually take them. Diet never work--unless you actually eat them. So what's the point of telling people to eat strictly plant-based if few people will do it? So by soft-peddling the truth and coming up with a compromise diet you can imagine how they were thinking that on a population clae they might be doing more good. Ok, but tell that to the thousand U.S. families a day that lose a loved one to high blood pressure. Maybe it's time to start telling the American public the truth.

Sacks himself found that the more dairy the lactovegetarians ate, the higher their blood pressures. But they had to make the diet acceptable. Research has since shown that it's the added plant foods--not the changes in oil, sweets, or dairy--that appears to the critical component of the DASH diet. So why not eat a diet composed entirely of plant foods?

A recent meta-analysis showed vegetarian diets are good, but strictly plant-based diets may be better. In general, vegetarian diets provide protection against cardiovascular diseases, some cancers, and even death. But completely plant-based diets seem to offer additional protection against obesity, hypertension, type-2 diabetes, and heart disease mortality. Based on a study of more than 89,000 people, those eating meat-free diets appear to cut their risk of high blood pressure in half. But those eating meat-free, egg-free, and dairy-free may have 75% lower risk.

What if we're already eating a whole food, plant-based diet, no processed foods, no table salt, yet still not hitting 110 over 70? Here are some foods recently found to offer additional protection: Just a few tablespoons of ground flaxseeds a day was 2 to 3 times more potent than instituting an aerobic endurance exercise program and induced one of the most powerful, antihypertensive effects ever achieved by a diet-related intervention. Watermelon also appears to be extraordinary, but you'd have to eat around 2 pounds a day. Sounds like my kind of medicine, but it's hard to get year-round (at least in my neck of the woods). Red wine may help, but only if the alcohol has been taken out. Raw vegetables or cooked? The answer is both, though raw may work better. Beans, split peas, chickpeas, and lentils may also help a bit.

Kiwifruits don't seem to work at all, even though the study was funded by a kiwifruit company. Maybe they should have taken direction from the California Raisin Marketing Board, which came out with a study showing raisins can reduce blood pressure, but only, apparently, compared to fudge cookies, Cheez-Its, and Chips Ahoy.

The DASH diet is one of the best studied, and it consistently ranks as US News & World Report's #1 diet. It's one of the few diets that medical students are taught about in medical school. I was so fascinated to learn of its origins as a compromise between practicality and efficacy.

I've talked about the patronizing attitude many doctors have that patients can't handle the truth in:

What would hearing the truth from your physician sound like? See Fully Consensual Heart Disease Treatment and The Actual Benefit of Diet vs. Drugs.

For more on what plants can do for high blood pressure, 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: Sally Plank. This image has been modified.

Original Link

How Much Water Should We Drink Every Day?

How Much Water Should We Drink Every Day?.jpeg

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

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

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

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

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

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

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

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

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

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

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

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

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

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

In health,

Michael Greger, M.D.

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

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

Original Link

How Much Water Should We Drink Every Day?

How Much Water Should We Drink Every Day?.jpeg

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

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

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

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

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

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

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

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

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

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

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

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

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

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

In health,

Michael Greger, M.D.

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

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

Original Link

What 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

Four Ways to Improve on the Mediterranean Diet

Improving on the Mediterranean Diet.jpg

The traditional Mediterranean diet can be considered mainly, but not exclusively, as a plant-based diet, and certainly not a whole foods, plant-based diet. Olive oil and wine can be considered essentially fruit juices. Even if one is eating a "vegiterranean diet," an entirely plant-based version, there are a number of problematic nutritional aspects that are rarely talked about. For example, the Mediterranean diet includes lots of white bread, white pasta and not a lot of whole grains.

In an anatomy of the health effects of the Mediterranean diet, the single most important component was the high consumption of plant foods. In contrast, high cereal consumption, meaning high grain consumption, did not appear to help. This may be because most grains that modern Mediterranean dieters eat are refined, like white bread, whereas the traditional Mediterranean diet was characterized by unprocessed cereals--in other words, whole grains. And while whole grains have been associated with lower risk of diabetes, heart disease and cancer, refined grain may increase the risk of diabetes, obesity, heart disease and other chronic diseases. In the PREDIMED study, those who ate the most white bread--but not whole grain bread--gained significant weight.

Alcohol may also be a problem. As a plant-centered diet, adherence to a Mediterranean diet is associated with lower cancer risk, but does not appear to lower breast cancer risk. With all the fruits, veggies, nuts, seeds, beans and low saturated fat content, you'd assume there would be lower breast cancer risk, but alcohol is a known breast carcinogen, even in moderate amounts. When researchers created a special adapted version of the Mediterranean diet score that excluded alcohol, the diet does indeed appear to reduce breast cancer risk.

The wonderful grape phytonutrients in red wine can improve our arterial function such that if you drink nonalcoholic red wine (wine with the alcohol removed), you get a significant boost in endothelial function--the ability of our arteries to relax and dilate normally, increasing blood flow. If you drink the same red wine with alcohol, it abolishes the beneficial effect and counteracts the benefit of the grape phytonutrients. So, it would be better just to eat grapes. You can find more information about this in my video Improving on the Mediterranean Diet.

Similarly, there are components of extra virgin olive oil--the antioxidant phytonutrients, that may help endothelial function, but when consumed as oil, (even extra virgin olive oil), it may impair arterial function. So even if white bread dipped in olive oil is the very symbol of the Mediterranean diet, we can modernize it by removing oils and refined grains.

Another important, albeit frequently ignored issue in the modern Mediterranean diet is sodium intake. Despite evidence linking salt intake to high blood pressure, heart disease and strokes, dietary salt intake in the U.S. is on the rise. Right now, Americans get about seven to ten grams a day, mostly from processed foods. If we were to decrease that just by three grams every year, we could possibly save tens of thousands of people from having a heart attack, prevent tens of thousands of strokes, and tens of thousands of deaths. There is a common misperception that only certain people should reduce their salt intake and that for the vast majority of the population, salt reduction is unnecessary, but in reality, the opposite is true.

There is much we can learn from the traditional Mediterranean diet. A defining characteristic of the Mediterranean diet is an abundance of plant foods, but one thing that seems to have fallen by the wayside. No main Mediterranean meal is replete without lots of greens, a key part of not only a good Mediterranean diet, but of any good diet.

Here are some of my previous videos on the Mediterranean diet:

I touch more on whole grains in How Many Meet the Simple Seven? and Whole Grains May Work As Well As Drugs.

More on breast cancer and alcohol in Breast Cancer and Alcohol: How Much Is Safe?, Preventing Skin Cancer From the Inside Out, and Breast Cancer Risk: Red Wine v. White Wine.

I've touched on olive oil in the other videos in this Mediterranean diet series, but also have an older video Extra Virgin Olive Oil vs. Nuts and more recently, Olive Oil & Artery Function.

More on sodium in Dietary Guidelines: With a Grain of Big Salt, Big Salt - Getting to the Meat of the Matter, and Can Diet Protect Against Kidney Cancer? But what if without salt everything tastes like cardboard? Not to worry! See Changing Our Taste Buds.

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

Four Ways to Improve on the Mediterranean Diet

Improving on the Mediterranean Diet.jpg

The traditional Mediterranean diet can be considered mainly, but not exclusively, as a plant-based diet, and certainly not a whole foods, plant-based diet. Olive oil and wine can be considered essentially fruit juices. Even if one is eating a "vegiterranean diet," an entirely plant-based version, there are a number of problematic nutritional aspects that are rarely talked about. For example, the Mediterranean diet includes lots of white bread, white pasta and not a lot of whole grains.

In an anatomy of the health effects of the Mediterranean diet, the single most important component was the high consumption of plant foods. In contrast, high cereal consumption, meaning high grain consumption, did not appear to help. This may be because most grains that modern Mediterranean dieters eat are refined, like white bread, whereas the traditional Mediterranean diet was characterized by unprocessed cereals--in other words, whole grains. And while whole grains have been associated with lower risk of diabetes, heart disease and cancer, refined grain may increase the risk of diabetes, obesity, heart disease and other chronic diseases. In the PREDIMED study, those who ate the most white bread--but not whole grain bread--gained significant weight.

Alcohol may also be a problem. As a plant-centered diet, adherence to a Mediterranean diet is associated with lower cancer risk, but does not appear to lower breast cancer risk. With all the fruits, veggies, nuts, seeds, beans and low saturated fat content, you'd assume there would be lower breast cancer risk, but alcohol is a known breast carcinogen, even in moderate amounts. When researchers created a special adapted version of the Mediterranean diet score that excluded alcohol, the diet does indeed appear to reduce breast cancer risk.

The wonderful grape phytonutrients in red wine can improve our arterial function such that if you drink nonalcoholic red wine (wine with the alcohol removed), you get a significant boost in endothelial function--the ability of our arteries to relax and dilate normally, increasing blood flow. If you drink the same red wine with alcohol, it abolishes the beneficial effect and counteracts the benefit of the grape phytonutrients. So, it would be better just to eat grapes. You can find more information about this in my video Improving on the Mediterranean Diet.

Similarly, there are components of extra virgin olive oil--the antioxidant phytonutrients, that may help endothelial function, but when consumed as oil, (even extra virgin olive oil), it may impair arterial function. So even if white bread dipped in olive oil is the very symbol of the Mediterranean diet, we can modernize it by removing oils and refined grains.

Another important, albeit frequently ignored issue in the modern Mediterranean diet is sodium intake. Despite evidence linking salt intake to high blood pressure, heart disease and strokes, dietary salt intake in the U.S. is on the rise. Right now, Americans get about seven to ten grams a day, mostly from processed foods. If we were to decrease that just by three grams every year, we could possibly save tens of thousands of people from having a heart attack, prevent tens of thousands of strokes, and tens of thousands of deaths. There is a common misperception that only certain people should reduce their salt intake and that for the vast majority of the population, salt reduction is unnecessary, but in reality, the opposite is true.

There is much we can learn from the traditional Mediterranean diet. A defining characteristic of the Mediterranean diet is an abundance of plant foods, but one thing that seems to have fallen by the wayside. No main Mediterranean meal is replete without lots of greens, a key part of not only a good Mediterranean diet, but of any good diet.

Here are some of my previous videos on the Mediterranean diet:

I touch more on whole grains in How Many Meet the Simple Seven? and Whole Grains May Work As Well As Drugs.

More on breast cancer and alcohol in Breast Cancer and Alcohol: How Much Is Safe?, Preventing Skin Cancer From the Inside Out, and Breast Cancer Risk: Red Wine v. White Wine.

I've touched on olive oil in the other videos in this Mediterranean diet series, but also have an older video Extra Virgin Olive Oil vs. Nuts and more recently, Olive Oil & Artery Function.

More on sodium in Dietary Guidelines: With a Grain of Big Salt, Big Salt - Getting to the Meat of the Matter, and Can Diet Protect Against Kidney Cancer? But what if without salt everything tastes like cardboard? Not to worry! See Changing Our Taste Buds.

In health,

Michael Greger, M.D.

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

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

Original Link

The Two Most Active Ingredients of the Mediterranean Diet

Which Parts of the Mediterranean Diet Extended Life.jpg

Olives and nuts are plant foods, and as such, are packed with antioxidants, raising the antioxidant level of our bloodstream resulting in lower fat oxidation and free radical DNA damage, but what's happening inside people's arteries?

Researchers measured the amount of atherosclerotic plaque in the neck arteries going to the brain in folks who for years were eating added nuts, added extra virgin olive oil or neither to their daily diets. In the control group, the plaque got worse, which is what happens when one continues to eat an artery-clogging diet, but there were no significant changes in the added extra virgin olive oil group, and the plaque in the added nut group appeared to get better. The nuts appeared to induce a regression of the disease, or at least a significant delay in the progression. The nut group was still suffering strokes, but only half as many, perhaps because the reduction in plaque height within the arteries on extra nuts was indicating a stabilization of the plaque, rendering them less likely to rupture. You can see these results in my video Which Parts of the Mediterranean Diet Extended Life?

Adding nuts to our diet may also improve endothelial function, boosting the ability of our arteries to dilate naturally by about 30 percent. If you look at the baseline adherence to Mediterranean diet principles and control for things like smoking and exercise, there were only two factors significantly associated with reduced heart attack and stroke risk: more vegetables and more nuts. No significant association with the olive oil, wine, fish or cutting back on soda and cookies. Among the individual components, only increased consumption of vegetables and nuts were related to reduced cardiovascular events.

On the one hand, cutting stroke risk in half just by eating a handful of nuts a day is pretty amazing, but those in the added nut group didn't appear to live any longer overall. This is in contrast to other studies that suggested that frequent nut consumption may extend life. For example, the Harvard health professionals studies, involving a whopping three million person-years of follow-up over decades, found nut consumption associated with fewer deaths from cancer, heart disease, respiratory disease and most importantly fewer deaths overall. This was confirmed by all the other big major prospective studies in a recent review.

So what's going on here with the study showing no longevity benefit from nuts? Did they just not wait long enough? Just because people were randomized to the nut group didn't mean they actually ate more nuts, and those randomized to the other groups didn't necessarily stay away.

If you re-analyze the data comparing the death rates of those who actually ate more nuts to those who actually didn't, nut consumption was indeed associated with significantly reduced risk of death. If you do the same kind of post hoc analysis with olive oil, even with the extra virgin, there is no benefit in terms of living longer. This is consistent with how Ancel Keys, the so-called Father of the Mediterranean diet, viewed olive oil. He thought of its benefit more as a way of just replacing animal fats; anything to get people to eat less lard and butter.

What is the best kind of nut? The greatest benefits were attributed to walnuts, particularly for preventing cancer deaths. Those eating more than three servings of walnuts a week appeared to cut their risk of dying from cancer in half.

Now it's just a matter of communicating the research to the public. All the major cancer groups emphasize a more plant-based diet, remarkably consistent with the World Health Organization guidelines for healthy eating. The far-reaching positive effects of a plant-based diet--including walnuts--may be the most critical message for the public.

Here are some of my previous videos on the Mediterranean diet:

Think the effects of adding a few nuts to one's daily diet are too good to believe? Check out my video Four Nuts Once a Month. For more on Walnuts and Artery Function check out the video, and for more on nuts and cancer prevention, see Which Nut Fights Cancer Better?

Nuts May Help Prevent Death and so may beans; see Increased Lifespan from Beans. What about Fruits and Longevity: How Many Minutes per Mouthful?

More on protecting ourselves from "brain attacks" in Preventing Strokes with Diet.

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: garlandcannon / Flickr. This image has been modified.

Original Link

The Two Most Active Ingredients of the Mediterranean Diet

Which Parts of the Mediterranean Diet Extended Life.jpg

Olives and nuts are plant foods, and as such, are packed with antioxidants, raising the antioxidant level of our bloodstream resulting in lower fat oxidation and free radical DNA damage, but what's happening inside people's arteries?

Researchers measured the amount of atherosclerotic plaque in the neck arteries going to the brain in folks who for years were eating added nuts, added extra virgin olive oil or neither to their daily diets. In the control group, the plaque got worse, which is what happens when one continues to eat an artery-clogging diet, but there were no significant changes in the added extra virgin olive oil group, and the plaque in the added nut group appeared to get better. The nuts appeared to induce a regression of the disease, or at least a significant delay in the progression. The nut group was still suffering strokes, but only half as many, perhaps because the reduction in plaque height within the arteries on extra nuts was indicating a stabilization of the plaque, rendering them less likely to rupture. You can see these results in my video Which Parts of the Mediterranean Diet Extended Life?

Adding nuts to our diet may also improve endothelial function, boosting the ability of our arteries to dilate naturally by about 30 percent. If you look at the baseline adherence to Mediterranean diet principles and control for things like smoking and exercise, there were only two factors significantly associated with reduced heart attack and stroke risk: more vegetables and more nuts. No significant association with the olive oil, wine, fish or cutting back on soda and cookies. Among the individual components, only increased consumption of vegetables and nuts were related to reduced cardiovascular events.

On the one hand, cutting stroke risk in half just by eating a handful of nuts a day is pretty amazing, but those in the added nut group didn't appear to live any longer overall. This is in contrast to other studies that suggested that frequent nut consumption may extend life. For example, the Harvard health professionals studies, involving a whopping three million person-years of follow-up over decades, found nut consumption associated with fewer deaths from cancer, heart disease, respiratory disease and most importantly fewer deaths overall. This was confirmed by all the other big major prospective studies in a recent review.

So what's going on here with the study showing no longevity benefit from nuts? Did they just not wait long enough? Just because people were randomized to the nut group didn't mean they actually ate more nuts, and those randomized to the other groups didn't necessarily stay away.

If you re-analyze the data comparing the death rates of those who actually ate more nuts to those who actually didn't, nut consumption was indeed associated with significantly reduced risk of death. If you do the same kind of post hoc analysis with olive oil, even with the extra virgin, there is no benefit in terms of living longer. This is consistent with how Ancel Keys, the so-called Father of the Mediterranean diet, viewed olive oil. He thought of its benefit more as a way of just replacing animal fats; anything to get people to eat less lard and butter.

What is the best kind of nut? The greatest benefits were attributed to walnuts, particularly for preventing cancer deaths. Those eating more than three servings of walnuts a week appeared to cut their risk of dying from cancer in half.

Now it's just a matter of communicating the research to the public. All the major cancer groups emphasize a more plant-based diet, remarkably consistent with the World Health Organization guidelines for healthy eating. The far-reaching positive effects of a plant-based diet--including walnuts--may be the most critical message for the public.

Here are some of my previous videos on the Mediterranean diet:

Think the effects of adding a few nuts to one's daily diet are too good to believe? Check out my video Four Nuts Once a Month. For more on Walnuts and Artery Function check out the video, and for more on nuts and cancer prevention, see Which Nut Fights Cancer Better?

Nuts May Help Prevent Death and so may beans; see Increased Lifespan from Beans. What about Fruits and Longevity: How Many Minutes per Mouthful?

More on protecting ourselves from "brain attacks" in Preventing Strokes with Diet.

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: garlandcannon / Flickr. This image has been modified.

Original Link