335 replies to this topic

[DukeNukem]

I am thinking to go on no carb diet since some weeks. the only thing which keeps me from doing that is that i would avoid eating tomato, apples, oranges, carrot, blueberries...that in many studies have shown to improve health.

Also, without them, i would be forced to go on supplements for many vitamins and i prefer to get all i need from food if possible.

People doing no-carb diet aren't worried to miss the health vitamins in fruit and vegetables ?

To be perfectly clear, a paleo diet is not a no-carb diet. Look at this blog entry yesterday from a paleo blogger. In other threads I've posted links to other vegetable-packed paleo meals. The key is that these vegetables are mostly water (by weight) unlike starchy veggies, beans and grains. If you just completely stay away from grains then that's most of the battle. Berries and colorful vegetables are all fair game.

[Shepard]

And, if you allow dairy and tubers in your definition of paleo, you've got those too, along with fruit. That is essentially my standard diet.

[kismet]

What about the methylglyoxal issue? I'm sure you low carbers are familiar with it. If not: http://mfoundation.o...t=methylglyoxal

Do the benefits outweigh the risks?

Edited by kismet, 19 January 2009 - 09:18 PM.

[Prometheus]

What about the methylglyoxal issue? I'm sure you low carbers are familiar with it. If not: http://mfoundation.o...t=methylglyoxal

Do the benefits outweigh the risks?

What risks? Methylglyoxals are produced from an excess of glucose.

[DukeNukem]

What about the methylglyoxal issue? I'm sure you low carbers are familiar with it. If not: http://mfoundation.o...t=methylglyoxal

Do the benefits outweigh the risks?

Get your proanthocyanidins!

Honestly, who knows how this factors in. Maybe a healthy body handles it better. Maybe in vivo it's not nearly as much as an issue. I don't have a better answer now.

[kismet]

What risks? Methylglyoxals are produced from an excess of glucose.

And to a much greater degree from ketone metabolism as outlined by MR from the mfoundation (see the posted URL).

I'm wondering what you guys think the net effects are?

Edited by kismet, 19 January 2009 - 10:12 PM.

[FunkOdyssey]

Here's the one, singular study that everyone references when they talk about ketosis and methylglyoxal levels.

Ann N Y Acad Sci. 2005 Jun;1043:201-10.

Ketosis leads to increased methylglyoxal production on the Atkins diet.

Beisswenger BG, Delucia EM, Lapoint N, Sanford RJ, Beisswenger PJ.

Dartmouth Medical School, Dartmouth Hitchcock Medical Center, 1 Medical Center Drive, Lebanon, NH 03756, USA. paul.j.beisswenger@dartmouth.edu

In the popular and widely used Atkins diet, the body burns fat as its main fuel. This process produces ketosis and hence increased levels of beta-hydroxybutyrate (BOB) acetoacetate (AcAc) and its by-products acetone and acetol. These products are potential precursors of the glycotoxin methylglyoxal. Since methylglyoxal and its byproducts are recognized as a significant cause of blood vessel and tissue damage, we measured methylglyoxal, acetone, and acetol in subjects on the Atkins diet. We found that by 14-28 days, methylghyoxal levels rose 1.67-fold (P = 0.039) and acetol and acetone levels increased 2.7- and 6.12-fold, respectively (P = 0.012 and 0.028). Samples from subjects with ketosis showed even greater increases in methylglyoxal (2.12-fold), as well as acetol and acetone, which increased 4.19- and 7.9-fold, respectively; while no changes were seen in samples from noncompliant, nonketotic subjects. The increase in methylglyoxal implies that potential tissue and vascular damage can occur on the Atkins diet and should be considered when choosing a weight-loss program.

[FunkOdyssey]

Would methylglyoxal have dropped as they adapted to a ketogenic diet? They were only followed for 28 days. Does this phenomenon occur only in the initial phase of ketosis or always? Following long-term ketogenic dieters would have been more valuable to answer that particular question. Exactly how many carbs were they eating anyway? Would a moderate approach, with a bit higher carbs (lets say, 60-80g daily vs. Atkin's 20-40g) and a bit lower degree of ketosis, have produced any rise in methylglyoxal?

I think these are relevant questions.

Edited by FunkOdyssey, 19 January 2009 - 10:30 PM.

[DukeNukem]

Would methylglyoxal have dropped as they adapted to a ketogenic diet? They were only followed for 28 days. Does this phenomenon occur only in the initial phase of ketosis or always? Following long-term ketogenic dieters would have been more valuable to answer that particular question. Exactly how many carbs were they eating anyway? Would a moderate approach, with a bit higher carbs (lets say, 60-80g daily vs. Atkin's 20-40g) and a bit lower degree of ketosis, have produced any rise in methylglyoxal?

I think these are relevant questions.

Another point is that the paleo diet is not a ketogenic diet. Does the dramatic rise in methylglyoxal only happen during ketosis?

[Shepard]

Another point is that the paleo diet is not a ketogenic diet.

Technically, no. But if you're on a paleo diet without a decent amount of fruit and tubers, you're on a ketogenic diet.

Does the dramatic rise in methylglyoxal only happen during ketosis?

Ketosis is one pathway due to the rise in acetone levels, or it could be because of elevated lipid peroxidation.

Edited by shepard, 19 January 2009 - 10:48 PM.

[Mind]

Here is something that might add to the discussion about insulin sensitivity: Intermittent Fasting Improves Insulin Sensitivity

Small sample, but interesting.

and the paper

[Forever21]

Perhaps free to invent new anti-aging therapies that will allow us to enjoy whatever we want and then clean the damage later...lol.

Oh how I wish for this to happen. I wish MF would come up with something, anything, even just a small thing that fixes damages caused by food. I can't wait to go on a beef jerky & pork rinds diet.

Edited by Forever21, 19 January 2009 - 11:40 PM.

[Mind]

I wouldn't mind having a doughnut or a little more ice cream myself. mmmmm.

[HaloTeK]

I for one do not think carbohydrates are bad. In fact I make them my primary source of food, and I still have healthy blood sugar levels throughout the day and low fasting glucose (also, I move my body which may play a big part).
Folks on real CR have excellent biomarkers predicting long lives even though they eat alot of low caloric carbs and not much fat -- the very long-lived populations exceeding lifespans of 100 years also have eaten many carbs and not much fat (the 'poor man's diet') - and basically most vegetables and fruits are kingdoms of powerful disease-fighting nutrients, which it does make sense IMO to obtain in the natural state: locked inside the actual food.

I'm not convinced carbs are the complete enemy either. However, you need not remind me of the dangers inherent in fructose or sugar. Kenj, I'm interested to know if your blood sugars are low all day because of your weight rather than type of carbohydrate. Fit and lightweight people display an amazing ability to deal with carbs. This very much fits with what is known of the Kitava <----- my favorite people (low insulin, weight, high glycemic carb diet (potatoes)).

I'm also fearful of what your diet composition looks like when you adopt a high fat paleo diet. The composition of fats becomes questionable. Do you eat 2-3 ounces of almonds (lots of polyunsaturates, or hazelnuts, or even worse nuts, macadamias have too much omega 7 fat), do you use coconut oil (refined), olive oil (refined) or butter (refined), cream (refined)? What if you have nut allergies? What about the lysine /arginine content of nuts? What if you have dairy allergies? Seems to me that only consuming animal fats, you end up getting too much animal protein (high in methionine). And there is still the question of what kind of damage happens to fats once you injest them (AGEs, methylglyoxals).

People sometimes think you always need to be in a fat burning mode. At some point your body has to lay down fat. Why not have it be the stable saturated fat your body makes from carbohydrate? If you insulin levels are low all day from being fit and lightweight (like Kenj, or the Kitavans), carbs are a nice source of low AGE and polyunsated food if you pick tubers. Not to mention the fact that you have higher SHBG on a higher carb diet (less growth = better longevity).

The body likes to vary from growth and repair. Which is why people see pritty good results with IF. It's also good to remember that certain proteins really stimulate insulin (even without the glucose, like EGGS!).

We know that a low protein, low polyunsaturated fat diet is beneficial. On a Kitavan-type diet, you can really lower polyunsaturates more than a high fat paleo diet (unless it's sky high in saturated fat <---- which may disrupt insulin signaling). Until someone proves to me that absolute lower insulin (which average is probably lower for high fat paleos vs Kitavan-- but i'm not completely sure) is more important than an absolute lowering of hormones (high SHBG in high carb diet). Or that the AGEs, methylglyoxals, or polyunsaturates are really a non-issue with the high-fat paleo diet. I'd probably rather have my body make its own fats.

I'm really interested to see the difference in inflammation marker tests in the high fat paleo diets vs a Kitavan type diet. That might be the final bullet telling us what is optimal for maximal longevity.

(Side note: if I wanted growth or ease of weightloss, I'd go with a high fat, moderate protein, low carb diet. However, it is not the best for longevity)

[woly]

What do you think are the major mechanisms by which insulin lowers life expectancy?

At least one study shows that high insulin levels is a direct cause of plaque.

Would you be able to post a reference for that? sounds interesting.

[wydell]

I don't think ice cream, donuts or beef jerky three times a week will substantially effect your health provided you otherwise eat healthy and exercise. So I say, go ahead and eat it if you want. And maybe the enjoyment is even better for you than the abstinence.

Once summer comes around, I am going back to my home made xylitol ice cream twice per week.

I wouldn't mind having a doughnut or a little more ice cream myself. mmmmm.

[Shepard]

Not to mention the fact that you have higher SHBG on a higher carb diet (less growth = better longevity).

(Side note: if I wanted growth or ease of weightloss, I'd go with a high fat, moderate protein, low carb diet. However, it is not the best for longevity)

Can you provide a reference for your comment about SHBG? Higher insulin is correlated with lower SHBG levels. (1) Unless, you're just reinforcing the argument that higher carb diets could theoretically mean lower insulin than a low-carb diet.

Why would you want a low-carb diet for growth? Glucose deprivation -> AMPK activation -> Inhibited protein synthesis (2)


1. http://jcem.endojour...t/79/4/1173.pdf

2. Fulco M., Cen Y., Zhao P., Hoffman E.P., McBurney M.W., Sauve A.A., Sartorelli V.
Glucose Restriction Inhibits Skeletal Myoblast Differentiation by Activating SIRT1 through AMPK-Mediated Regulation of Nampt
(2008) Developmental Cell, 14 (5), pp. 661-673.

[Shepard]

I am going back to my home made xylitol ice cream twice per week.

Has anyone noticed that FOS powder tastes like cotton candy? I really wonder what options lie in cooking with the stuff. Although, too much might not be so good.

[DukeNukem]

What do you think are the major mechanisms by which insulin lowers life expectancy?

At least one study shows that high insulin levels is a direct cause of plaque.

Would you be able to post a reference for that? sounds interesting.

Try this for a summary, with references:
http://drbganimalpha...plaque-and.html

[Prometheus]

Here's the one, singular study that everyone references when they talk about ketosis and methylglyoxal levels.

Ann N Y Acad Sci. 2005 Jun;1043:201-10.

Ketosis leads to increased methylglyoxal production on the Atkins diet.

Beisswenger BG, Delucia EM, Lapoint N, Sanford RJ, Beisswenger PJ.

Dartmouth Medical School, Dartmouth Hitchcock Medical Center, 1 Medical Center Drive, Lebanon, NH 03756, USA. paul.j.beisswenger@dartmouth.edu

In the popular and widely used Atkins diet, the body burns fat as its main fuel. This process produces ketosis and hence increased levels of beta-hydroxybutyrate (BOB) acetoacetate (AcAc) and its by-products acetone and acetol. These products are potential precursors of the glycotoxin methylglyoxal. Since methylglyoxal and its byproducts are recognized as a significant cause of blood vessel and tissue damage, we measured methylglyoxal, acetone, and acetol in subjects on the Atkins diet. We found that by 14-28 days, methylghyoxal levels rose 1.67-fold (P = 0.039) and acetol and acetone levels increased 2.7- and 6.12-fold, respectively (P = 0.012 and 0.028). Samples from subjects with ketosis showed even greater increases in methylglyoxal (2.12-fold), as well as acetol and acetone, which increased 4.19- and 7.9-fold, respectively; while no changes were seen in samples from noncompliant, nonketotic subjects. The increase in methylglyoxal implies that potential tissue and vascular damage can occur on the Atkins diet and should be considered when choosing a weight-loss program.

Download the study and look at the data. In figure 4 graph A, they have 1338+/-1010 (Atkins) and 218+/-146 (pre-diet). N=10.
Where I went to school, if I presented that data to support a contention I would be told to go to the toilet (1).

(1) personal observation

[Mind]

Halotek: I'm really interested to see the difference in inflammation marker tests in the high fat paleo diets vs a Kitavan type diet. That might be the final bullet telling us what is optimal for maximal longevity.

Speaking from a layman's point of view, you are probably correct in that some people have a different body type/genetic make-up that helps them maintain low blood glucose levels and from a pure longevity standpoint they could probably handle more carbs than most (although overdoing it would still be bad), however that does not seem to be most people in the U.S. seeing that there is a raging obesity epidemic. For the average person looking for an healthy average lifespan it seems lower carbs would be the best advice (not necessarily zero carbs, but lower carbs: blueberries instead of bananas, whole grain instead of refined grains, etc...)

[Matt]

Although I think lower carb might be a better approach, I don't think it is needed to go as low as something like atkins in my opinion. Me personally, whatever I ate I had goog glucose control. When I used to eat 5 packets of crisps a day, chocolate bars, half a packet of chocolate biscuits, chips all the time and just complete crap. my fasting and non fasting glucose reading during that time was actually quite good at 4.5 (81mg/dl fasting. Though looking back I regret eating this way, but I think the being extremely fit and lean all my life probably helped a huge deal. Playing football for 4 hours a day for 12 years helped i'm sure LOL. I wish I knew about nutrition back then and my performance would have probably been far better. Just gotta look forward now I suppose

Edited by Matt, 20 January 2009 - 07:30 PM.

[Matt]

There was a great post by Michael in the CR Society lists where he talks about macronutrient ratios. Some older CR studies indicated that a higher protein (upto 50%) or a higher fat (upto 40% (60% fat was worse)) increases CR group maximum lifespan even further. Something to think about!

Edited by Matt, 20 January 2009 - 07:31 PM.

[stephen_b]

Did anyone else read these three articles, Low Carb Craziness: Part 1, Part 2, Part 3? It's not scientific in that he doesn't provide references for his conclusions, but I found his conclusions to track many of my own.

Some claims:

The intestinal tract simply does not tolerate that much meat. Studies have shown that when meat consumption goes over about 4 oz a day, beneficial bacterial counts in the colon drop by about 90%, and E. coli counts increase by some 900%.

* Generalization: Fat is bad. Specific: That's wrong! It misses the distinction between good (essential) fats and bad fats.

* Generalization: Saturated fat is bad. Specific: Wrong again! The right kind of saturated fat is essential. Coconut oil, one of the most saturated fats in existence, is one of the healthiest fats you can eat.

* Generalization: Carbohydrates are bad. Specific: Strike three! There are good carbs and bad carbs and, in fact, some carbs are just plain essential. (By the way, kudos to Dr. Mercola, who avoids this trap by calling his diet the No Grain Diet. But as it turns out, even that statement, as specific as it first seems, is still too much of a generalization and misses the mark!)

He likes (and has a financial stake in, it seems) sprouted barley for having a low glycemic index, 4+ hour digestion times, and high levels of beta glucans with enzymes preserved by the process this Swiss company developed. I don't know precisely how beta glucans and enzymes stack against the nutrients in leafy greens, for example, though of course one can have both.

StephenB

[Shepard]

Dude:

* Provides 400% more energy per calorie than meat

Uh, that's like saying a pound of feathers is more than a pound of steel.

There are good carbs and bad carbs and, in fact, some carbs are just plain essential.

Really, dietary carbs are essential? Like....what?

That's just after a couple of seconds of scanning. There are probably a few other good ones in there.

[FunkOdyssey]

The intestinal tract simply does not tolerate that much meat. Studies have shown that when meat consumption goes over about 4 oz a day, beneficial bacterial counts in the colon drop by about 90%, and E. coli counts increase by some 900%.

And let me guess, when you eat 4oz a day of sprouted barley, E. coli drops by 900% and beneficial bacterial counts rise 9000%? Just keep adding zeroes to your fake statistics until they pop off the page.

[stephen_b]

Wow, tough crowd. Maybe low carb eating does make you cranky.

Uh, that's like saying a pound of feathers is more than a pound of steel.

What's wrong with the following line of reasoning?

As it turns out, there are two different ways to test for caloric value. The traditional way is by burning the product to determine the energy released. This is the FDA approved standard. However, a more meaningful test is to measure the metabolic calorie value -- that is: how much energy the BODY can use or produce from the food in question.

It sounds reasonable to me that, since we don't burn our food in our digestive systems, maybe measuring the calories in a peanut by burning it misses out on some of the complexities of digestion.

Funk, four ounces of meat doesn't sound like that much, but my question is does meat intake past some point cause gut issues?

Unfortunately, the microbiota may also elaborate toxic products from food residues such as genotoxic hydrogen sulfide by sulfur-reducing bacteria in response to a high-meat diet. ... Evidence suggests that the diet directly influences the diversity of the microbiota, providing the link between diet, colonic disease, and colon cancer.

StephenB

Edit: PMID 16671057 would be an interesting paper to read, as it talks about how dietary AGEs affect gut populations.

Edited by stephen_b, 20 January 2009 - 08:50 PM.

[FunkOdyssey]

Funk, four ounces of meat doesn't sound like that much, but my question is does meat intake past some point cause gut issues?

Yes, beyond some point it probably does shift the colonic flora in ways that are undesirable -- I was just poking fun at the make-believe numbers that guy came up with. I could envision a meat-only diet increasing the risk of colon cancer. Fortunately, most paleo and healthy low-carb diets include copious amounts of dietary fiber which would support high populations of beneficial fermentative bacteria.

[Shepard]

What's wrong with the following line of reasoning?

As it turns out, there are two different ways to test for caloric value. The traditional way is by burning the product to determine the energy released. This is the FDA approved standard. However, a more meaningful test is to measure the metabolic calorie value -- that is: how much energy the BODY can use or produce from the food in question.

It sounds reasonable to me that, since we don't burn our food in our digestive systems, maybe measuring the calories in a peanut by burning it misses out on some of the complexities of digestion.

The human body is not a bomb calorimeter, no.

For Aktivated Barley, the metabolic calorie value is 400% higher than a standard calorie such as fat. Or to look at it another way, with Aktivated Barley you get the same energy on 1/4 the calories VS standard calories.

So, he's either suggesting that the human body doesn't extract energy well from non-barley food (unlikely considering the fat-assness of the population), or the body is producing more energy than is available and violating the laws of thermodynamics.

[kismet]

Download the study and look at the data. In figure 4 graph A, they have 1338+/-1010 (Atkins) and 218+/-146 (pre-diet). N=10.
Where I went to school, if I presented that data to support a contention I would be told to go to the toilet (1).

(1) personal observation

I think testing mechanistic markers does not require big sample sizes. I'm assuming the SD is explained by the "Atkins-cheaters" who were not in ketosis. Still the data is rather lacking, but it could be backed if we knew the pathways of ketone energy metabolism (maybe there are some known pathways directly leading to methyglyoxal production which would make the case pretty clear).

It is backed by in vitro data (yay!), but the link is still described as putative.

Metabolism. 2008 Sep;57(9):1211-20.
Methylglyoxal production in vascular smooth muscle cells from different metabolic precursors.
Dhar A, Desai K, Kazachmov M, Yu P, Wu L.