Paleo Lifestyle Change?

The thread is long gone... might as well discuss...

When enough protein is consumed, gluconeogenesis can supply all the glucose the body requires while still maintaining lean body mass.

http://www.ncbi.nlm.nih.gov/pubmed/7351177

The subjects were both sedentary and obese.

People in that condition can eat not only zero carb, but zero protein and zero fat and still be fine.

Not really, it's takes 1.6g's of protein to be converted to 1g of glucose and if no food whatsoever is consumed then lean mass is required for function. the egg protein did it's job in this scenario. i would have to look at trained people, but I would suspect that the only extra afford would be a higher consumption of protein to help stay in nitrogen balance, but I'm not sure.

That's how I read the abstract too.

I'd still be interested in learning more about the long term impact of a carb-free lifestyle.

My understanding has been that using glycogen from protein builds up toxins that can damage the liver and that the brain requires a level of glycogen that can't be met with fat alone. Sure, in the short-term survival situation we can adapt, but there are long-term effects to excluding one of the three macro-nutrients.

I'm not sure about toxins and liver damage, I've not heard of that, but there may be concerns. Also being in ketosis doesn't mean no carbs.....some trained athletes can consume 100g of carbs and still be in ketosis, most people could probably consume 50+ and still be in ketosis. Maybe look at populations that might live this way and look at their health, the Inuit for example, they seemed to thrive pretty well for the majority of the year considering they've been around 30-40,000 yrs. Anyway gluconeogenesis happens 24 hours a day regardless, so I would imagine the body doesn't see this as minor phenomena that could cause damage. But I really don't know, just a guess.

I'm not sure about toxins and liver damage, I've not heard of that, but there may be concerns. Also being in ketosis doesn't mean no carbs.....some trained athletes can consume 100g of carbs and still be in ketosis, most people could probably consume 50+ and still be in ketosis. Maybe look at populations that might live this way and look at their health, the Inuit for example, they seemed to thrive pretty well for the majority of the year considering they've been around 30-40,000 yrs. Anyway gluconeogenesis happens 24 hours a day regardless, so I would imagine the body doesn't see this as minor phenomena that could cause damage. But I really don't know, just a guess.

Because the climate of the Arctic is ill-suited for agriculture and lacks forageable plant matter for much of the year, the traditional Inuit diet is unusually low in carbohydrates and high in fat and animal protein. In the absence of carbohydrates, protein is broken down in the liver through gluconeogenesis and utilized as an energy source. Inuit studied in the 1970s were found to have abnormally large livers, presumably to assist in this process. Their urine volumes were also high, a result of the excess urea produced by gluconeogenesis.

I'm not sure about toxins and liver damage, I've not heard of that, but there may be concerns. Also being in ketosis doesn't mean no carbs.....some trained athletes can consume 100g of carbs and still be in ketosis, most people could probably consume 50+ and still be in ketosis. Maybe look at populations that might live this way and look at their health, the Inuit for example, they seemed to thrive pretty well for the majority of the year considering they've been around 30-40,000 yrs. Anyway gluconeogenesis happens 24 hours a day regardless, so I would imagine the body doesn't see this as minor phenomena that could cause damage. But I really don't know, just a guess.

The Inuit are a good example.

Because the climate of the Arctic is ill-suited for agriculture and lacks forageable plant matter for much of the year, the traditional Inuit diet is unusually low in carbohydrates and high in fat and animal protein. In the absence of carbohydrates, protein is broken down in the liver through gluconeogenesis and utilized as an energy source. Inuit studied in the 1970s were found to have abnormally large livers, presumably to assist in this process. Their urine volumes were also high, a result of the excess urea produced by gluconeogenesis.

http://en.wikipedia.org/wiki/Inuit_diet#Nutrition

It looks like they've physically adapted to a low-carb life. That's kind of fascinating.

http://www.medicalnewstoday.com/articles/180858.php

Ketosis is a condition in which levels of ketones (ketone bodies) in the blood are elevated. Ketones are formed when glycogen stores in the liver have run out.

The ketones - acetoacetate and β-hydroxybutyrate - are used for energy. Ketones are small carbon fragments that are the fuel created by the breakdown of fat stores. Ketosis is potentially a serious condition if keytone levels go too high.

However, when the body is in ketosis the individual tends to feel less hungry, and will probably eat less than he/she might otherwise do. The body switches from being a carbohydrate-burning organism into a fat-burning one. The fat stores become a primary energy source, and the person loses weight. That is why low-carb diets have become popular, and effective, especially among obese people.

The modern human body in most societies usually metabolizes glucose from carbohydrates for energy purposes, rather than energy from fat. If there is not enough glucose (from carbohydrates) in the bloodstream the body draws on fat stores for fuel, causing the appearance of ketones in the blood. Ketones are produced by the liver from fatty acids.

We need proteins and fats for building and repairing tissue and cells - proteins and fats can also be sources of energy. If necessary, the body can get all its energy from fats and proteins.

Our brain can use glucose or ketones for energy; it cannot generally burn fat for energy. A study carried out at the Psychology Department of Tufts University in Medford, Massachusetts found that women on low- or zero-carb diets performed worse in memory or thinking tests than women whose diets were not low in carbs.

When there are plenty of carbohydrates in the body, it breaks them down into glucose, which is then converted into energy and transported into the cells of our body.

If glucose cannot be broken down, as may be the case if the insulin levels are too low, or if there is a lack of glucose, then the body has to break down stored fat and convert it into energy. Metabolizing fat raises blood ketone levels, leading to ketosis. Ketosis can occur with Type 1 diabetes (not enough insulin), alcoholism, starvation, and with a low-carb, high fat/protein diet.

Ketones consist of acetone, acetoacetate or beta-hydroxybutyrate. Very high ketone levels can be toxic, making the blood more acid, and may damage such organs as the kidneys and liver.

The human body tries to lower acetone (a ketone) levels by breathing it out, causing a sweet and fruity breath. We also reduce keytone levels by expelling them through our urine.

Low Carb Diet Is Bad For Thinking And Memory
Thursday 11 December 2008 - 11am PST
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Low Carb Diet Is Bad For Thinking And Memory
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A new study from scientists in the US found that when women went on low or zero-carb diets they performed worse on thinking and memory tests compared to reducing calories without reducing carbohydrates. When they put carbs back into their diet, their thinking and memory skills went back to normal.

The study was the work of researchers from the psychology department of Tufts University in Medford, Massachusetts. It is published in the February 2009 journal Appetite and is already available to view online.

Dr Holly Taylor, professor of psychology at Tufts and corresponding author of the study, said the findings showed that:

"The food you eat can have an immediate impact on cognitive behavior."

"The popular low-carb, no-carb diets have the strongest potential for negative impact on thinking and cognition," she added.

Taylor's co-authors and research colleagues were Professor Robin Kanarek, former undergraduate Kara Watts and research associate Kristen D'Anci.

Our brain cells need glucose to work, but they have no way of storing it so they rely on a continuous supply via the bloodstream. The researchers had a hunch that reducing carbohydrate intake would reduce the body's ability to keep the brain supplied with glucose and therefore affect cognition, since glucose comes from breaking down carbohydrates.

For the study, Taylor and colleagues recruited 19 women aged 22 to 55 and let them each choose to go on either a low carb or low calorie diet as recommended by the American Dietetic Association. Nine of them chose the low carb diet and the other 10 chose the low calorie diet.

Altogether the participants attended five assessment sessions. Session 1 was just before they started on their chosen diet, sessions 2 and 3 were during the first week of dieting (when the low-carb dieters eliminated carbohydrates), and sessions 4 and 5 were in weeks 2 and 3, after the low-carb dieters started eating carbohydrates again.

During the assessment sessions the dieters performed a range of tests that measured attention, short and long term memory, visual attention and spatial memory. They also answered questions about how hungry they felt and their mood.

The results showed that:

Low carb dieters showed a gradual decrease on memory tasks compared with low-calorie dieters.

Reaction time for the low-carb dieters was slower, and their visual-spatial memory was not as good as that of the low-calorie dieters.

But low-carb dieters responded better than low-calorie dieters in the attention-vigilance tasks.

This last result is consistent with previous studies that found people on high protein or high fat diets showed short term improvements in attention.

http://www.medicalnewstoday.com/articles/180858.php

Ketosis is a condition in which levels of ketones (ketone bodies) in the blood are elevated. Ketones are formed when glycogen stores in the liver have run out.

The ketones - acetoacetate and β-hydroxybutyrate - are used for energy. Ketones are small carbon fragments that are the fuel created by the breakdown of fat stores. Ketosis is potentially a serious condition if keytone levels go too high.

However, when the body is in ketosis the individual tends to feel less hungry, and will probably eat less than he/she might otherwise do. The body switches from being a carbohydrate-burning organism into a fat-burning one. The fat stores become a primary energy source, and the person loses weight. That is why low-carb diets have become popular, and effective, especially among obese people.

The modern human body in most societies usually metabolizes glucose from carbohydrates for energy purposes, rather than energy from fat. If there is not enough glucose (from carbohydrates) in the bloodstream the body draws on fat stores for fuel, causing the appearance of ketones in the blood. Ketones are produced by the liver from fatty acids.

We need proteins and fats for building and repairing tissue and cells - proteins and fats can also be sources of energy. If necessary, the body can get all its energy from fats and proteins.

Our brain can use glucose or ketones for energy; it cannot generally burn fat for energy. A study carried out at the Psychology Department of Tufts University in Medford, Massachusetts found that women on low- or zero-carb diets performed worse in memory or thinking tests than women whose diets were not low in carbs.

When there are plenty of carbohydrates in the body, it breaks them down into glucose, which is then converted into energy and transported into the cells of our body.

If glucose cannot be broken down, as may be the case if the insulin levels are too low, or if there is a lack of glucose, then the body has to break down stored fat and convert it into energy. Metabolizing fat raises blood ketone levels, leading to ketosis. Ketosis can occur with Type 1 diabetes (not enough insulin), alcoholism, starvation, and with a low-carb, high fat/protein diet.

Ketones consist of acetone, acetoacetate or beta-hydroxybutyrate. Very high ketone levels can be toxic, making the blood more acid, and may damage such organs as the kidneys and liver.

The human body tries to lower acetone (a ketone) levels by breathing it out, causing a sweet and fruity breath. We also reduce keytone levels by expelling them through our urine.

Some misinformation there. The initial stages of low carb is the transition to ketones and the fogginess is normal, which disappears after a few weeks.

Here's the result of that study.

Low Carb Diet Is Bad For Thinking And Memory
Thursday 11 December 2008 - 11am PST
Nutrition / Diet
Neurology / Neuroscience
Psychology / Psychiatry
add your opinion
email
MNT Featured
Add your rating
Current ratings for:
Low Carb Diet Is Bad For Thinking And Memory
Public / Patient:
1 2 3 4 5
25 ratings
Health Professionals:
1 2 3 4 5
11 ratings
A new study from scientists in the US found that when women went on low or zero-carb diets they performed worse on thinking and memory tests compared to reducing calories without reducing carbohydrates. When they put carbs back into their diet, their thinking and memory skills went back to normal.

The study was the work of researchers from the psychology department of Tufts University in Medford, Massachusetts. It is published in the February 2009 journal Appetite and is already available to view online.

Dr Holly Taylor, professor of psychology at Tufts and corresponding author of the study, said the findings showed that:

"The food you eat can have an immediate impact on cognitive behavior."

"The popular low-carb, no-carb diets have the strongest potential for negative impact on thinking and cognition," she added.

Taylor's co-authors and research colleagues were Professor Robin Kanarek, former undergraduate Kara Watts and research associate Kristen D'Anci.

Our brain cells need glucose to work, but they have no way of storing it so they rely on a continuous supply via the bloodstream. The researchers had a hunch that reducing carbohydrate intake would reduce the body's ability to keep the brain supplied with glucose and therefore affect cognition, since glucose comes from breaking down carbohydrates.

For the study, Taylor and colleagues recruited 19 women aged 22 to 55 and let them each choose to go on either a low carb or low calorie diet as recommended by the American Dietetic Association. Nine of them chose the low carb diet and the other 10 chose the low calorie diet.

Altogether the participants attended five assessment sessions. Session 1 was just before they started on their chosen diet, sessions 2 and 3 were during the first week of dieting (when the low-carb dieters eliminated carbohydrates), and sessions 4 and 5 were in weeks 2 and 3, after the low-carb dieters started eating carbohydrates again.

During the assessment sessions the dieters performed a range of tests that measured attention, short and long term memory, visual attention and spatial memory. They also answered questions about how hungry they felt and their mood.

The results showed that:

Low carb dieters showed a gradual decrease on memory tasks compared with low-calorie dieters.

Reaction time for the low-carb dieters was slower, and their visual-spatial memory was not as good as that of the low-calorie dieters.

But low-carb dieters responded better than low-calorie dieters in the attention-vigilance tasks.

This last result is consistent with previous studies that found people on high protein or high fat diets showed short term improvements in attention.

Basically in low carb their memory was impared, but did better in doing tasks that required more attention and concentration. Also they said very high level of ketones can be toxic, well that's not correct. It's ketoacidosis that can be toxic and that happens in the absence of insulin.........our pH levels drop and it becomes a medical emergency. Alcoholics and type 1 diabetics could be in harms way, but the average person, pretty much negligible. A bit of a propoganda piece or maybe just repeating another article without editing.

http://www.medicalnewstoday.com/articles/180858.php

Ketosis is a condition in which levels of ketones (ketone bodies) in the blood are elevated. Ketones are formed when glycogen stores in the liver have run out.

The ketones - acetoacetate and β-hydroxybutyrate - are used for energy. Ketones are small carbon fragments that are the fuel created by the breakdown of fat stores. Ketosis is potentially a serious condition if keytone levels go too high.

However, when the body is in ketosis the individual tends to feel less hungry, and will probably eat less than he/she might otherwise do. The body switches from being a carbohydrate-burning organism into a fat-burning one. The fat stores become a primary energy source, and the person loses weight. That is why low-carb diets have become popular, and effective, especially among obese people.

The modern human body in most societies usually metabolizes glucose from carbohydrates for energy purposes, rather than energy from fat. If there is not enough glucose (from carbohydrates) in the bloodstream the body draws on fat stores for fuel, causing the appearance of ketones in the blood. Ketones are produced by the liver from fatty acids.

We need proteins and fats for building and repairing tissue and cells - proteins and fats can also be sources of energy. If necessary, the body can get all its energy from fats and proteins.

Our brain can use glucose or ketones for energy; it cannot generally burn fat for energy. A study carried out at the Psychology Department of Tufts University in Medford, Massachusetts found that women on low- or zero-carb diets performed worse in memory or thinking tests than women whose diets were not low in carbs.

When there are plenty of carbohydrates in the body, it breaks them down into glucose, which is then converted into energy and transported into the cells of our body.

If glucose cannot be broken down, as may be the case if the insulin levels are too low, or if there is a lack of glucose, then the body has to break down stored fat and convert it into energy. Metabolizing fat raises blood ketone levels, leading to ketosis. Ketosis can occur with Type 1 diabetes (not enough insulin), alcoholism, starvation, and with a low-carb, high fat/protein diet.

Ketones consist of acetone, acetoacetate or beta-hydroxybutyrate. Very high ketone levels can be toxic, making the blood more acid, and may damage such organs as the kidneys and liver.

The human body tries to lower acetone (a ketone) levels by breathing it out, causing a sweet and fruity breath. We also reduce keytone levels by expelling them through our urine.

Some misinformation there. The initial stages of low carb is the transition to ketones and the fogginess is normal, which disappears after a few weeks.

Here's the result of that study.

Low Carb Diet Is Bad For Thinking And Memory
Thursday 11 December 2008 - 11am PST
Nutrition / Diet
Neurology / Neuroscience
Psychology / Psychiatry
add your opinion
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MNT Featured
Add your rating
Current ratings for:
Low Carb Diet Is Bad For Thinking And Memory
Public / Patient:
1 2 3 4 5
25 ratings
Health Professionals:
1 2 3 4 5
11 ratings
A new study from scientists in the US found that when women went on low or zero-carb diets they performed worse on thinking and memory tests compared to reducing calories without reducing carbohydrates. When they put carbs back into their diet, their thinking and memory skills went back to normal.

The study was the work of researchers from the psychology department of Tufts University in Medford, Massachusetts. It is published in the February 2009 journal Appetite and is already available to view online.

Dr Holly Taylor, professor of psychology at Tufts and corresponding author of the study, said the findings showed that:

"The food you eat can have an immediate impact on cognitive behavior."

"The popular low-carb, no-carb diets have the strongest potential for negative impact on thinking and cognition," she added.

Taylor's co-authors and research colleagues were Professor Robin Kanarek, former undergraduate Kara Watts and research associate Kristen D'Anci.

Our brain cells need glucose to work, but they have no way of storing it so they rely on a continuous supply via the bloodstream. The researchers had a hunch that reducing carbohydrate intake would reduce the body's ability to keep the brain supplied with glucose and therefore affect cognition, since glucose comes from breaking down carbohydrates.

For the study, Taylor and colleagues recruited 19 women aged 22 to 55 and let them each choose to go on either a low carb or low calorie diet as recommended by the American Dietetic Association. Nine of them chose the low carb diet and the other 10 chose the low calorie diet.

Altogether the participants attended five assessment sessions. Session 1 was just before they started on their chosen diet, sessions 2 and 3 were during the first week of dieting (when the low-carb dieters eliminated carbohydrates), and sessions 4 and 5 were in weeks 2 and 3, after the low-carb dieters started eating carbohydrates again.

During the assessment sessions the dieters performed a range of tests that measured attention, short and long term memory, visual attention and spatial memory. They also answered questions about how hungry they felt and their mood.

The results showed that:

Low carb dieters showed a gradual decrease on memory tasks compared with low-calorie dieters.

Reaction time for the low-carb dieters was slower, and their visual-spatial memory was not as good as that of the low-calorie dieters.

But low-carb dieters responded better than low-calorie dieters in the attention-vigilance tasks.

This last result is consistent with previous studies that found people on high protein or high fat diets showed short term improvements in attention.

Basically in low carb their memory was impared, but did better in doing tasks that required more attention and concentration. Also they said very high level of ketones can be toxic, well that's not correct. It's ketoacidosis that can be toxic and that happens in the absence of insulin.........our pH levels drop and it becomes a medical emergency. Alcoholics and type 1 diabetics could be in harms way, but the average person, pretty much negligible. A bit of a propoganda piece or maybe just repeating another article without editing.

But everything I read about ketosis states that as a risk:

http://www.webmd.com/diet/high-protein-low-carbohydrate-diets

What Are the Risks Linked to High Protein, Low-Carb Diets?

High protein, low-carb diets can cause a number of health problems, including:

- Kidney failure. Consuming too much protein puts a strain on the kidneys, which can make a person susceptible to kidney disease.
- High cholesterol . It is well known that high-protein diets (consisting of red meat, whole dairy products, and other high fat foods) are linked to high cholesterol. Studies have linked high cholesterol levels to an increased risk of developing heart disease, stroke, and cancer.
- Osteoporosis and kidney stones. High-protein diets have also been shown to cause people to excrete a large amount of calcium in their urine. Over a prolonged period of time, this can increase a person's risk of osteoporosis and kidney stones. A diet that increases protein at the expense of a very restrictive intake of plant carbohydrates may be bad for bones, but not necessarily a high-protein intake alone.
- Cancer. One of the reasons high-protein diets increase the risks of certain health problems is because of the avoidance of carbohydrate-containing foods and the vitamins, minerals, fiber, and antioxidants they contain. It is therefore important to obtain your protein from a diet rich in whole grains, fruits, and vegetables. Not only are your needs for protein being met, but you are also helping to reduce your risk of developing cancer.
- Unhealthy metabolic state (ketosis). Low-carb diets can cause your body to go into a dangerous metabolic state called ketosis since your body burns fat instead of glucose for energy. During ketosis, the body forms substances known as ketones, which can cause organs to fail and result in gout, kidney stones, or kidney failure. Ketones can also dull a person's appetite, cause nausea and bad breath. Ketosis can be prevented by eating at least 100 grams of carbohydrates a day.

http://www.medicalnewstoday.com/articles/180858.php

Ketosis is a condition in which levels of ketones (ketone bodies) in the blood are elevated. Ketones are formed when glycogen stores in the liver have run out.

The ketones - acetoacetate and β-hydroxybutyrate - are used for energy. Ketones are small carbon fragments that are the fuel created by the breakdown of fat stores. Ketosis is potentially a serious condition if keytone levels go too high.

However, when the body is in ketosis the individual tends to feel less hungry, and will probably eat less than he/she might otherwise do. The body switches from being a carbohydrate-burning organism into a fat-burning one. The fat stores become a primary energy source, and the person loses weight. That is why low-carb diets have become popular, and effective, especially among obese people.

The modern human body in most societies usually metabolizes glucose from carbohydrates for energy purposes, rather than energy from fat. If there is not enough glucose (from carbohydrates) in the bloodstream the body draws on fat stores for fuel, causing the appearance of ketones in the blood. Ketones are produced by the liver from fatty acids.

We need proteins and fats for building and repairing tissue and cells - proteins and fats can also be sources of energy. If necessary, the body can get all its energy from fats and proteins.

Our brain can use glucose or ketones for energy; it cannot generally burn fat for energy. A study carried out at the Psychology Department of Tufts University in Medford, Massachusetts found that women on low- or zero-carb diets performed worse in memory or thinking tests than women whose diets were not low in carbs.

When there are plenty of carbohydrates in the body, it breaks them down into glucose, which is then converted into energy and transported into the cells of our body.

If glucose cannot be broken down, as may be the case if the insulin levels are too low, or if there is a lack of glucose, then the body has to break down stored fat and convert it into energy. Metabolizing fat raises blood ketone levels, leading to ketosis. Ketosis can occur with Type 1 diabetes (not enough insulin), alcoholism, starvation, and with a low-carb, high fat/protein diet.

Ketones consist of acetone, acetoacetate or beta-hydroxybutyrate. Very high ketone levels can be toxic, making the blood more acid, and may damage such organs as the kidneys and liver.

The human body tries to lower acetone (a ketone) levels by breathing it out, causing a sweet and fruity breath. We also reduce keytone levels by expelling them through our urine.

Some misinformation there. The initial stages of low carb is the transition to ketones and the fogginess is normal, which disappears after a few weeks.

Here's the result of that study.

Low Carb Diet Is Bad For Thinking And Memory
Thursday 11 December 2008 - 11am PST
Nutrition / Diet
Neurology / Neuroscience
Psychology / Psychiatry
add your opinion
email
MNT Featured
Add your rating
Current ratings for:
Low Carb Diet Is Bad For Thinking And Memory
Public / Patient:
1 2 3 4 5
25 ratings
Health Professionals:
1 2 3 4 5
11 ratings
A new study from scientists in the US found that when women went on low or zero-carb diets they performed worse on thinking and memory tests compared to reducing calories without reducing carbohydrates. When they put carbs back into their diet, their thinking and memory skills went back to normal.

The study was the work of researchers from the psychology department of Tufts University in Medford, Massachusetts. It is published in the February 2009 journal Appetite and is already available to view online.

Dr Holly Taylor, professor of psychology at Tufts and corresponding author of the study, said the findings showed that:

"The food you eat can have an immediate impact on cognitive behavior."

"The popular low-carb, no-carb diets have the strongest potential for negative impact on thinking and cognition," she added.

Taylor's co-authors and research colleagues were Professor Robin Kanarek, former undergraduate Kara Watts and research associate Kristen D'Anci.

Our brain cells need glucose to work, but they have no way of storing it so they rely on a continuous supply via the bloodstream. The researchers had a hunch that reducing carbohydrate intake would reduce the body's ability to keep the brain supplied with glucose and therefore affect cognition, since glucose comes from breaking down carbohydrates.

For the study, Taylor and colleagues recruited 19 women aged 22 to 55 and let them each choose to go on either a low carb or low calorie diet as recommended by the American Dietetic Association. Nine of them chose the low carb diet and the other 10 chose the low calorie diet.

Altogether the participants attended five assessment sessions. Session 1 was just before they started on their chosen diet, sessions 2 and 3 were during the first week of dieting (when the low-carb dieters eliminated carbohydrates), and sessions 4 and 5 were in weeks 2 and 3, after the low-carb dieters started eating carbohydrates again.

During the assessment sessions the dieters performed a range of tests that measured attention, short and long term memory, visual attention and spatial memory. They also answered questions about how hungry they felt and their mood.

The results showed that:

Low carb dieters showed a gradual decrease on memory tasks compared with low-calorie dieters.

Reaction time for the low-carb dieters was slower, and their visual-spatial memory was not as good as that of the low-calorie dieters.

But low-carb dieters responded better than low-calorie dieters in the attention-vigilance tasks.

This last result is consistent with previous studies that found people on high protein or high fat diets showed short term improvements in attention.

Basically in low carb their memory was impared, but did better in doing tasks that required more attention and concentration. Also they said very high level of ketones can be toxic, well that's not correct. It's ketoacidosis that can be toxic and that happens in the absence of insulin.........our pH levels drop and it becomes a medical emergency. Alcoholics and type 1 diabetics could be in harms way, but the average person, pretty much negligible. A bit of a propoganda piece or maybe just repeating another article without editing.

But everything I read about ketosis states that as a risk:

http://www.webmd.com/diet/high-protein-low-carbohydrate-diets

What Are the Risks Linked to High Protein, Low-Carb Diets?

High protein, low-carb diets can cause a number of health problems, including:

- Kidney failure. Consuming too much protein puts a strain on the kidneys, which can make a person susceptible to kidney disease.
- High cholesterol . It is well known that high-protein diets (consisting of red meat, whole dairy products, and other high fat foods) are linked to high cholesterol. Studies have linked high cholesterol levels to an increased risk of developing heart disease, stroke, and cancer.
- Osteoporosis and kidney stones. High-protein diets have also been shown to cause people to excrete a large amount of calcium in their urine. Over a prolonged period of time, this can increase a person's risk of osteoporosis and kidney stones. A diet that increases protein at the expense of a very restrictive intake of plant carbohydrates may be bad for bones, but not necessarily a high-protein intake alone.
- Cancer. One of the reasons high-protein diets increase the risks of certain health problems is because of the avoidance of carbohydrate-containing foods and the vitamins, minerals, fiber, and antioxidants they contain. It is therefore important to obtain your protein from a diet rich in whole grains, fruits, and vegetables. Not only are your needs for protein being met, but you are also helping to reduce your risk of developing cancer.
- Unhealthy metabolic state (ketosis). Low-carb diets can cause your body to go into a dangerous metabolic state called ketosis since your body burns fat instead of glucose for energy. During ketosis, the body forms substances known as ketones, which can cause organs to fail and result in gout, kidney stones, or kidney failure. Ketones can also dull a person's appetite, cause nausea and bad breath. Ketosis can be prevented by eating at least 100 grams of carbohydrates a day.