My Paleo

While trying to figure out the biological mechanisms is interesting, I think it really is simple. We are omnivores. We can and do thrive on either a high fat or high carb diet. Environment would play the biggest role. In the the summer more carbs where available, in winter meat/fat would be the bulk of the diet if not exclusively. In tropical environments coconut, cassava, and taro are diet staples available year round. There is probably a certain amount of variation between populations/individuals on whether they do better on one side or the other. Another interesting theory Ive hear is that it may be good to continually switch from one to the other.
One things for certain, processed food culture is way higher in carb calories and very low on satiety. Add in the engineered addictive tastes and oxidized omega 6 oils and its a recipe for disaster.
there is no denying that tons of people have turned their health around in shockingly dramatic ways be eating low carb whole foods. That doesn't mean "carbs" are bad just that something about a life time of eating a very high carb junk food diet did something to the metabolism and the brain that a temporary low carb diet helped heal. Diabetics are another matter and I won't pretend to know much about that side of it.
I know I spent over a year doing daily fasts and eating very low carb and I had more energy then I ever had. I didn't bonk. I would do what ever activity I was doing until I was too sore or ran out of breath. I had no need to "refuel". Food made me tired and lazy like after a Thanksgiving meal so I on;y eat something of substance at night after work when I was ready for rest and sleep. That life style worked better when I was single and could plan out my days and meals more strictly, now I usually eat twice a day and eat much higher carb ( root vegetables mostly). My energy is not as high as it once was but I feel good. Ill be much better when spring comes and I can be more active outside.

Jeremy, very big +1 to Gary Taubes. His book "Good Calories, Bad Calories" is what originally got me started on all this. I first learned about it when I was hiking the Juan de Fuca Marine Trail on Vancouver Island, Canada, back in 2009. I by chance met someone at the youth hostel I was staying at in Victoria who asked to go on the walk with me. It turned out he was a licensed diabetic educator and he recommended the book to me (though now that I look back at it, his peanut butter and jam stuffed tortilla rolls that he exclusively ate weren't much inspiration! o_O" ). It took about a year before I mustered up the energy to tackle this tome, but when I did it completely turned everything I knew about food on its head, and especially put into perspective how the American food industry, medical establishment, and government had willfully distorted or neglected to balance out the information we have had about carbohydrates and fat. It is one of the best written, fair, and well-researched examples of scientific journalism that I have read. I very highly recommend it as a start to understanding why much of the medical advice about food that have dominated the media and medical profession for the last 40 years needs to be critically reexamined. It is also a good start for understanding the basics of why a fat-centered metabolism is so important.

I just read an excellent article:

http://boingboing.net/2012/03/09/seduced-by-food-obesity-and-t.html

I think this article will help clarify things for people who still believe in the status quo views on obesity. He gives a good laymans explanation of the energy homeostasis system. A fact of human biology the government and media ( at the behest of big-Agra ) don't ever want you know about.

A lot of paleo proponents (including Stephan Guyenet who wrote the boing boing article) are moving away from the Gary Taubes theory of obesity (Carbs lead to high insulin lead to fat storage).

A lot of paleo proponents (including Stephan Guyenet who wrote the boing boing article) are moving away from the Gary Taubes theory of obesity (Carbs lead to high insulin lead to fat storage).

Hmm. Except that when you're a diabetic you use a blood glucose meter everyday to measure how much sugar is in your blood at any given time. I've been keeping records four times a day now for 2 years, comparing the level of my blood sugar after any carb and fat ingestion (I've been keeping BG records for 12 years, but without the extra watching of carb ingestion). Every time I eat a certain amount of carbs my blood sugar shoots up a certain amount. Every time I eat mostly fat my blood sugar doesn't budge. I have to increase or decrease the amount of insulin I inject according to how high my blood sugar is. Every diabetic knows this and has the same experience. The amount of carbs we eat, and correspondingly how much insulin we inject also directly affects how much fat we put on. It most definitely is not a "theory". I measure and watch it everyday. Millions of diabetics do.

"My point is more that glucose metabolism shouldn't necessarily be considered the body's "primary energy source", even though that's what tends to get taught first in school."

We are in complete agreement there, Jeremy.

At this point I do have clear the air, at least from my point of view. In our dialogue to date, I get the impression that both you and Miguel think I am saying that glucose metabolism is the body's primary energy source. Nothing could be further from the truth, and nothing I have posted to date implies that. So, to state it as clearly as I can:

1) At normal levels of activity, fat is the primary source of energy for human metabolism.

2) Some glucose is used to support the efficient of fat at any level of activity where fat is being used, assuming glucose is available.

3) As the intensity of exercise increases, glucose will provide an increasing amount of the energy required to support that level of activity until the glucose supply is exhausted or the activity level decreases, at which point the process reverses. It is not a black and white situation, rather a sliding scale where the ration of fat to glucose varies with the intensity of the activity.

4) The glucose system is not an emergency system. Rather, it is an integral part of a very flexible energy supply system that allows for maximum performance under widely varying conditions.

"Such "endurance training" results in reduced use of carbohydrate for a given level of exercise, and a higher aerobic capacity will also allow a greater amount of energy to come from fatty acid metabolism. (Fatty acids are preferentially metabolized over glucose.)"

Again, no argument whatsoever. That is the way the system works, and has for millenia, but that does not reduce the glucose system to the status of an emergency system. It is part of the mix at all times, assuming glucose is available. The true emergency system, as I posted above, is the stored ATP/Creatine phosphate system, which enables a person to respond almost instantaneously and anaerobically to an unexpected threatening or opportunistic event at a very high level of intensity that could not be supported by either the glucose or fat components of the energy system. At lower levels of activity, the emergency system would be ketosis, and to a lesser degree gluconeogenisis, which enable an individual to function but at a much lower level of intensity and efficiency.

Tom,

It seems that we're all in agreement then, and your and Jeremy's explanations about the biochemistry have definitely added to my understanding of all this.

Using the words "emergency system" is probably incorrect. Thanks for clearing that up.

However, I'd have to argue that staying at a lower level of activity and using a slow burn to keep yourself going is a very efficient state to be in. All animals and plants do as much as possible to use as little energy as possible to get through their days, only upping their exertion levels when hunting or fleeing or mating or playing. So I'd say keeping exertion levels low and steady is the preferred state for the body.

"If you think about it, Tom, even your scenario of hunting logically supports fat metabolism as the primary, day-in and day-out energy source."

Miguel, I am mystified by your continued assumption that I think glucose is the primary energy source for humans. As I posted to Jeremy, nothing I have said to date remotely implies that. What I did say, and repeat in my latest post to Jeremy, is that the glucose energy system is an integral part of the overall human energy system and is active all the time, to one degree or another, depending on the activity level and the individual's cardio vascular fitness. The exception is when there is a true emergency that requires an immediate high intensity response or when glucose supplies have been exhausted. Nor have I ever advocated a high carb diet. My only staterment to date on diet was to state my belief in a balanced approach. The human body does not need to switch over to burning fat. It has been doing so for as long as the human race has been around, just like our ancestors before us on down the line to early mammals. The energy system we have inherited has been around for a very long time.

"And thereby marathon runners experience "the wall" "

It is a bit more complicated than that. Hitting the wall has a lot to do with the intensity of the exercise and a person's VO2 max. The higher one's VO2 max, the more fat will be in the mix, which means the longer that person can go before exhausting their glucose supply that is being used to support the metabolism of fat. World class runners have such a high VO2 max that they do not slow down appreciably all the way to the finish. For the rest of us the wall is a fact of life. For some it will be 18 miles, for others 20, and so on. For those who go out too fast it will come perhaps half way thru the race, reflecting an over dependence on glucose due to a lower VO2 max. The salient point here is that the more oxygen you can deliver to the cells, the more you will be able to utilize your fat stores and spare your glucose, thereby extending your ability to perform at a high intensity, or for a longer time at a lower intensity. At a very slow pace, guys like Mittelman can extend their effort for a very long time, but eventually it will also require taking in food, including carbs, as the race continues. This is how ultra marathoners do their thing, a lesson I learned the hard way once upon a time.

"Hunting long distances could not have been maintained with constant all out effort; as you detailed, the high energy output could only have gone on for about 6 to 8 miles. Most of the "running" would have been in the realm of endurance athletes today (like Stu Mittleman, who has run across the breadth of the United States in one go), which stays at a relatively slow pace (Mittleman beats his opponents in being able to maintain a very low pace for very sustainable periods, and repeating that over and over again until he wears everyone else down) that utilizes the fat mechanism most of the time, and the glucose mechanism only when short bursts of energy are needed."

Agreed, except that the glucose system is involved all the time, just at a lower level. It is not an either/or system, Miguel. As long as glucose is available, it will supply some of the energy. One of the most basic axioms of exercise physiology is: "Fat burns in a carbohydrate flame". It has to do with the specific series of biochemical reactions that oxidize fatty acids and glucose. I'll leave it at that to avoid a horrifically complicated and unnecessary explanation that would give us all a headache.

"However, I'd have to argue that staying at a lower level of activity and using a slow burn to keep yourself going is a very efficient state to be in. All animals and plants do as much as possible to use as little energy as possible to get through their days, only upping their exertion levels when hunting or fleeing or mating or playing. So I'd say keeping exertion levels low and steady is the preferred state for the body."

A big plus one!

"It seems that we're all in agreement then, and your and Jeremy's explanations about the biochemistry have definitely added to my understanding of all this."

The end result of a very good dialogue. Thanks Miguel, Jeremy, and others.

The energy system we have inherited has been around for a very long time.

And that's what the whole paleo thought process tries to work with and understand. No? That's even why it's called, "paleo". However, much of what we eat today definitely has not been around a very long time.

It is a bit more complicated than that.

Yes, I really do understand that. Just bringing up one of the points about how to eat for long distances and high exertion. I'm certain that there is much more going on than my simplistic explanation allows.

Agreed, except that the glucose system is involved all the time, just at a lower level. It is not an either/or system, Miguel.

Er, are we both not reading each other's posts all the way through? I thought I just explained, through my example of how insulin is used in diabetes, that I am aware of glucose being constantly in use.

I'll leave it at that to avoid a horrifically complicated and unnecessary explanation that would give us all a headache.

This is definitely a maddeningly complicated subject! Most definitely! The more I inch my way through the information, the more confusing it gets. I don't know how anyone could possibly understand it all with any degree of certainty.

Tom, if I seem argumentative, sorry. It's just that I'm confused by your posts. On one hand you seem to be agreeing with what Jeremy and I have been saying, and yet on the other you seem annoyed by what we are saying. Aren't we in agreement at this point, but perhaps finding it hard to see it because of the abstraction of discussing this via the Internet? And again, please understand that I cannot go on to discuss the biochemical background behind all this. I just don't know enough. But I think I am getting the gist of it, no?

Edit: Tom, it seems I just missed your last post! Things are looking up! (^J^)/"

"However, much of what we eat today definitely has not been around a very long time."

I think that is exactly the problem. Abuse of a system that has served mankind well for a very long time. It just wasn't designed to handle either the amount of food we take in or the amount of carbs, especially the high GI refined variety, we throw at it these days.

"Er, are we both not reading each other's posts all the way through?"

I think we were posting at the same time based on each other's previous posts.

"I thought I just explained, through my example of how insulin is used in diabetes, that I am aware of glucose being constantly in use."

True, but I distinguish between the blood glucose you measure and that which is being used in the muscle cells, either for energy production or storage as glycogen for later use. Maybe I'm being picky, but the latter is not a cause for concern, whereas the former clearly can be.

"I don't know how anyone could possibly understand it all with any degree of certainty."

I don't think anybody does. There are gaps in our knowledge, and ongoing research is bringing new discoveries constantly. Also, evolution does not stand still; change is constant and you can be sure that, as we change our environment as an evolutionarily breakneck rate, our bodies are adapting or attempting to adapt. There will always be much to learn.

"Tom, if I seem argumentative, sorry. It's just that I'm confused by your posts. On one hand you seem to be agreeing with what Jeremy and I have been saying, and yet on the other you seem annoyed by what we are saying."

I wasn't at all annoyed by what you and Jeremy were saying, but I was frustrated that you seemed to be ignoring or misinterpreting what I was saying. It also occurred to me that I wasn't being clear enough, which is why I re-posted my basic premises in bullet form. Then there is the difficulty inherent in trying to conduct a dialogue on a subject as complex as this one via the Internet, as yo0u point out.

"But I think I am getting the gist of it, no?"

Very much so, and that was my main reason for posting in the first place. Now you will be in a much better position to evaluate what you read in your ongoing quest to manage your diabetes in a way that maximizes your enjoyment of your life. I also got a lot out of this thread, and will be following this and any future threads having to do with the subject, be they Paleo, ketogenic diet, diabetes, or…. One of my quirks is that while I am not a gear nerd, I do confess to a certain nerdishness when it comes to optimizing the food I carry when backpacking for performance and weight. Any discussion like this one helps me refine my thinking and reevaluate what I am doing, so it is a win win situation. Not to mention I really enjoy a lively discussion that remains civil and focused. This one has been a model in that regard from my point of view. Thanks to all.

"Hmm. Except that when you're a diabetic you use a blood glucose meter everyday to measure how much sugar is in your blood at any given time. I've been keeping records four times a day now for 2 years, comparing the level of my blood sugar after any carb and fat ingestion (I've been keeping BG records for 12 years, but without the extra watching of carb ingestion). Every time I eat a certain amount of carbs my blood sugar shoots up a certain amount. Every time I eat mostly fat my blood sugar doesn't budge. I have to increase or decrease the amount of insulin I inject according to how high my blood sugar is. Every diabetic knows this and has the same experience. The amount of carbs we eat, and correspondingly how much insulin we inject also directly affects how much fat we put on. It most definitely is not a "theory". I measure and watch it everyday. Millions of diabetics do."

Hi Miguel

The part of the Taubes theory that many question is that the raised insulin leads to obesity. I think it's a pretty well established fact that eating carbs raises insulin. But many paleo proponents are doubting that the insulin "spikes" that you get after eating carbs are somehow driving fat storage. Insulin spikes would be in the context of a non diabetic individual. This would be very different from someone who is insulin resistant and has chronically elevated insulin levels. The human body is pretty complicated and there is lots more going on with other hormones like leptin etc that seem to be involved in getting fat. I certainly don't understand it all. I don't doubt your observations in your own case and would probably follow something nearly identical if I was in your own shoes.

I've followed a more or less "Paleo" diet for the last 2 years. I have never been obese, more like carrying an extra 20 lbs that I was not able to loose with the standard diets (whole grains/low fat yada yada) which only made me hungry and I was never able to loose more than a couple of lbs with. I more or less followed the Mark Sisson Approach keeping carbs under 150 grams/day. It was the only diet that seemed to work for me and I lost a good amount of weight but I kind of doublt that it was just cutting carbs that did it. Another "Paleo" blogger that I followed and respect is Kurt Harris (Archevore blog). His Archevore diet steps pretty much summarize his philosophy, which is essentially to avoid what he calls the neolithic agents of disease. The big ones are wheat, sugar and seed oils. The blog is worth a read.

The part of the Taubes theory that many question is that the raised insulin leads to obesity. I think it's a pretty well established fact that eating carbs raises insulin. But many paleo proponents are doubting that the insulin "spikes" that you get after eating carbs are somehow driving fat storage. Insulin spikes would be in the context of a non diabetic individual.

Daniel, thanks for the detailed reply. I have to disagree with you about there being a difference between a diabetic and a normal person. Insulin and carbs work exactly the same way for all human beings, regardless of whether they are normal, have obesity, or are diabetic. The insulin spikes I get are exactly the same as when your blood sugar gets elevated when you eat carbs, especially simple sugars. The only difference is that there has been so much spiking of insulin production in my body (most likely because my body just happened to be more sensitive to carbs than most people) my pancreas became exhausted and stopped producing insulin, and so, without taking artificial insulin (or for people who can still produce some insulin, insulin inducing medicine) the sugar in my blood and muscles keeps elevating higher and higher until eventually I would die. Diabetics are normal in every way except the inability to produce insulin, as I've pointed out several times. I'm not sure why people always assume that diabetics are somehow different. There is no foreign agent in our bodies. We just can't produce insulin.

I think it is very telling that the lack of insulin and the presence of high amounts of glucose in the body can produce such horrific results, and should very much serve to warn those who are not yet diabetic of the dangers of carbs. I see full blown diabetes as the far end of a spectrum of reactions to too much sugar in the blood… obesity being a stepping stone towards diabetes and related to it. Obesity is also known as "hyperinsulinemia"… where the body overproduces insulin in response to too much ingestion of carbs.

Diabetics tend to be fat, especially Type 2 diabetics. They are fat before they become diabetic and after they start taking insulin. However, at the onset of diabetes they suddenly severely lose weight. One of the classic signs of becoming diabetic is emaciation and terrible hunger. Pre-treated diabetics can eat, and eat, and never get satiated, while losing more and more weight until they die. It is the absence of insulin that causes this. The more carbs an untreated diabetic eats, the more they will lose weight. In the days before artificial insulin, diabetics were kept alive by going on severely carb restricted diets. With the invention of insulin, diabetics could once again eat regular food, including carbs, and gain their weight back. However, because they have become sensitive to carbs, they must keep the carbs lower than normal people. Eating too many carbs means increasing the dosages of insulin, which in turn brings on the fat.

The normal human body works exactly the same way, but the natural insulin that humans produce is a 1000 times more effective than artificial insulin and is far more finely regulated. Only about 40% of artificial insulin is actually effective, and therefore more insulin has to be injected to counteract the ingestion of carbs. More injected insulin means a greater liability to gain weight.

I acknowledge that it is all far more complicated than what I just wrote, but the principles that Mark Sisson talks about and how he explains getting healthy for normal people, work on exactly the same principles that endocrinologists work with with diabetics.

I have been reading Archevore for quite some time. Great blog. And definitely challenges certain assumptions that paleo enthusiasts make. He's occasionally a bit more technical than I can keep up with, but he definitely knows he stuff very well.

Pretty significant boost to the idea that going low-fat is the cause of today's obesity, diabetes, heart disease epidemics: World Renowned Heart Surgeon Speaks Out On What Really Causes Heart Disease.

I googled it and found this:
http://www.preventdisease.com/news/12/030112_World-Renown-Heart-Surgeon-Speaks-Out-On-What-Really-Causes-Heart-Disease.shtml

Also many other links to the exact same title

Unfortunately they're all to obscure sources and I always have a feeling they're trying to con me into buying something : )

But he says simple carbs like sugar, white flour, potatoes, and white rice are killing us

and omega 6 fatty acids which you find in corn, soy, and sun flower oils

I didn't see him mention it, but you also find omega 6 in your regular corn fed beef

"But he says simple carbs like sugar, white flour, potatoes, and white rice are killing us"

It's because most Americans eat far too much of it in processed foods and do far too little exercise. They take in too many calories and so they get fat and can't figure out why their hearts give out.

Not sure if the medical profession is 'coming around' or one heart surgeon is but I am ignoring the generalization.

It is, of course, the nature of the beast – forget moderation and swing completely the 'other' way.

Speaking of weird reports, there was one today:

Why Are Animals Getting Fatter, Too?

As many have said above, one study is not an end-truth. That said, it sure ranks under “weird ideas.”

Miguel has summed it up pretty well. As a Type 2 diabetic (caused by a combination of genetics and very poor lifestyle choices) I can concur with what he has said about the disease as it relates to T2 diabetes. When someone becomes obese or even overweight, especially around the abdomen, they can become diabetic. In fact, it is epicdemic in North America. There has also been some research done on the chemicals in our environment (BPA for example) and the effects on obesity and the endocrin system.

Non-diabetics, especially when doing vigorous activities, can have low blood sugars just like diabetics do. They don't have the highs because their body produces insulin in balance to the food. I ask the non-diabetics here… do you ever get that energy crash followed by extreme hunger? That's what a low is like for a diabetic too… although it can be deadly for a diabetic and it includes lack of concentration, reduced coordination, etc.. The antidote for a low… carbs. During exercise our muscles use up glycogen and if there isn't enough available fuel (from carbs) then the pancreas produces glucagon which gets the liver to convert the stored glycogen into glucose to replenish the stores. This is why sometimes diabetics can get a high glucose reading an hour after exercise if they haven't had enough carbohydrate for the activity. That is generally followed by a sudden drop. Also the blood glucose lowering affect can last 24 hours.

I think the goodness of the paleo diet is because it avoids sugar

See 60 Minutes piece:

http://www.cbsnews.com/8301-18560_162-57407294/is-sugar-toxic/?tag=contentMain;cbsCarousel

Sugar causes heart disease, obesity, diabetes, and cancer – explains the epedemic in the U.S. and huge health care costs

I'll throw in that white flour, white rice, and potatoes are just as bad, but normally people don't eat them to excess like sugar

This also explains goodness of low carb diets

Best thing about the piece is talking to a sugar grower representative who was in denial – sort of like tobacco people and global warming deniers.

Tom wrote "This amount of energy is enough to run 18-20 miles using very little fat for energy, at which point the glycogen is exhausted and the body must rely on fat and protein for its energy if it is to continue moving. When this happens, the runner's pace will tail off dramatically. It occurs to most marathoners somewhere between 18 and 20 miles, and is called 'hitting the wall'."

Tom, as a diabetic runner (unmedicated other than lifestyle) I've noticed something now that I've increased to 5K distances (which is considerably less than what you refer to). I need carbs or I hit my own personal wall at around the 3.5 K mark. Big time. If my blood sugar is at 5.0 mmol/L pre-run and I don't consume at least 35 to 45 grams of carbohydrate… then I finish the run utterly depleted. I've also found that not having enough carbs starts to make me deplete muscle and on the advice of my doc (Sports Med) I've had to increase carbohydrate intake. I've lost, since December 1st, 15 pounds and more importantly I've increased muscle mass with balancing the carb with adequate protein intake. I've also noticed that there are toned shape changes in my body (still with some room for improvement).

I've noticed that blood glucose is lower for 24 to 48 hours post run and that I seem to be metabolizing calories better.

Now on the days when I don't have enough carbs and I push myself through my personal barrier/wall… I have abnormally high blood glucose readings for several hours after while my liver has gone into hyper-drive to counteract the fact that I didn't have enough sustainable energy for the run.

While the Paleo might be good for sedentary weight loss I find it very difficult to make it fit within what I am doing from an activity/fitness perspective… I find it makes me feel like utter crap and I just don't have the endurance without the carb for energy.

Everyone has to find what works for them (with common sense of course).

Jerry wrote "Sugar causes heart disease, obesity, diabetes, and cancer – explains the epedemic in the U.S. and huge health care costs. I'll throw in that white flour, white rice, and potatoes are just as bad, but normally people don't eat them to excess like sugar"

I disagree…. keeping in mind that I have been at both ends of the scale. Sugar isn't the enemy and there are different types of sugar.

Take juice vs whole fruit as an example here. 1 cup of OJ is roughly equivalent to the juice of 3 or 4 oranges depending on the size. Some people drink juice as they would water. Choose the single whole orange and have it with a glass of water. You have the benefit of the fibre which makes the glycemic index lower. Juice is as bad as pop.

Pop (soda or whatever you choose to call it) is bad too. You wouldn't sit down and consume 10 to 15 packets of sugar, yet the average large pop from a take-out joint has about that much. I know folks who consume 2L of that a day and wonder why they are gaining weight.

Potatoes and sweet potatoes are not unhealthy and have nutrients but people slather them in butter and sour cream or other fats. Some people consume more than a standard serving. Four baby new potatoes have a mere 15 grams of carb. That is about the same as a small boiling potato or half a baking potato.

Refined sugars are bad. But it isn't just that…

It's being sedentary. Eating too much fat. Eating the wrong kinds of fat and sugars. Processed and convenience foods. Increased sodium intake. Take out foods. Portions that are too big… people eat far too much at one sitting. Being sedentary.

I know I said sedentary twice but many many of the cases of T2 diabetes aren't caused just by sugar intake. They are caused by belly fat from inactivity and ingesting more than the body can burn. The fatter around the middle you are the more at risk you are for diabetes because it disrupts insulin sensitivity. It also puts you at greater risk for cardiovascular disease. If you have diabetes you are at 6x greater risk for heart attack or stroke.

From a diabetic perspective… if blood glucose drops way too low the body craves carbs. In a non-diabetic eating too much refined sugar and processed carbohydrate can produce an increase in the bodies insulin and then trigger a lower blood sugar and further carb cravings. Then the body stores fat. That's why portion and moderation are key to preventing diabetes and obesity.

Choose the carbs wisely, limit the portion sizes, eat little amounts more frequently and live an active lifestyle is the preventative medicine… it's also the way to reverse T2 diabetes. I know, because I've done it. I was insulin dependent and now I live medication free while maintaining an hbA1C between 4.2 mmol/L and 5.0 mmol/L for a year now. The body was meant to move… not just every few weeks on a backpacking trips, but every single day.

Lifestyle, moderation, and physical activity are the keys to health. I'm walking or should I say running proof of that.

"While the Paleo might be good for sedentary weight loss I find it very difficult to make it fit within what I am doing from an activity/fitness perspective… I find it makes me feel like utter crap and I just don't have the endurance without the carb for energy."

Personal experience is the best teacher, Laurie. I could've gone on for pages and failed to convince you, or anyone else for that matter. What it boils down to is that you will use proportionally more carbs than fat as the intensity of the exercise increases, which is what you experienced with running. If you don't have carbs, the body will convert protein to carbs in an attempt to meet your carb need. The principles are the same for everybody. That said, the Paleo approach should work OK for less intense exercise, at least as far as the energy source is concerned. I still wonder about the long term effects of the Paleo diet on a person's health, though.

I hope you keep running the rest of your life. :)

You and I and the 60 Minutes piece do not disagree : )

They specifically gave the example that eating fruit is fine because the fiber delays metabolizing the sugar, i.e. has lower glycemic index, but drinking juice is as bad as soda.

The problem is that they put sugar (high fructose corn syrup) in everything and that's causing the epidemic of obesity, heart disease, diabetes, and cancer.

"While the Paleo might be good for sedentary weight loss I find it very difficult to make it fit within what I am doing from an activity/fitness perspective… I find it makes me feel like utter crap and I just don't have the endurance without the carb for energy."

I pretty much agree with what Tom said. Running 10 miles in an hour is a lot different than hiking 10 miles or even 20 miles in a day, in most situations.

But most of us aren't athletes running 100 miles per week. So there is a balance.

I don't think anyone can absolutely say how physically active our ancient ancestors were. But my studies on Native Americans indicate they were not out hunting or gathering everyday. A big kill or large harvest was not an on going struggle. They moved with the seasons to food sources and probably don't come close to the exertion of a marathoner in training/racking or a thru hiker. We can only speculate. It seems logical to me that a Paleo diet would would well for the average backpacker who maybe hikes a couple weekends a month and one or two longer trips during the year — that activity is probably similar to our ancient ancestors.

"The problem is that they put sugar (high fructose corn syrup) in everything and that's causing the epidemic of obesity, heart disease, diabetes, and cancer."

That's it, Jerry. When you start reading labels, it's amazing how ubiquitous high fructose corn syrup is. It seems like 3/4ths of the processed food we eat is basically flavored sugar.