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Nutrition Past and Future

TPNS 47-48: Low Carb, High Fad

Primitive Nutrition 47:
Low Carb, High Fad, Part I


The phrase low carb usually really means Low Carb High Fat.  It is nearly a consensus position in the low carb world that low carb high protein is not sustainable.  The objective in low carb high fat diets is to attain an unusual metabolic state called ketosis, in which the body's carbohydrate stores, in the form of glycogen, are depleted.  Consequently, acidic ketone bodies are created from stored fat, and they partially replace glucose as a fuel for your cells.

Ketogenic diets, or diets that induce ketosis, have been used since the 1920s to control intractable epileptic seizures in children.  It is from this therapeutic use that much of our understanding of these diets comes.  High fat diets have many of the same problems as high protein diets.  By limiting the consumption of healthy plant based foods they limit the intake of important nutrients.  While not saying so explicitly, low carb promoters acknowledge the nutritional inadequacy of these diets because they demand the use of multivitamins and other supplements. 

As we review some of the primitive nutrition logic that underlies low carb diets these days, remember that this aspect of the diet is quite necessarily modern.  Our ancestors did not have bottles of pills and powders.

Vitamin supplements are not a substitute for food.  Whereas plant foods have well-recognized disease fighting powers, the evidence for the benefits of vitamin supplements is a mixed bag.

Some actually can be harmful.

You won't find a well-designed study showing ill-effects from eating whole *plant foods, but vitamins have had a *bad run recently.

Multivitamins have recently been linked to breast cancer, for example.

And here they were found to just be mostly a waste of money.

Extracts of fruits and vegetables probably won't do you much good, either.  You have to actually eat these healthy foods, which would necessarily displace the low carb foods in your diet.

The fact is you just can't create a nutritious diet from vitamin supplements, at least not yet.  This is the conclusion I draw from the proven inadequacy of elemental diets.  Elemental diets are purified, easily-assimilated, supposedly complete nutrition formulas given to patients who cannot digest normal food.

Despite their increasing sophistication, deficiencies still result from them.  Generally they are used as little as possible, and this is one reason why. 

Dietary antioxidants make important contributions to health.  Beef USA will tell you that you should get them from food, not pills.  They'll also tell you fruits and vegetables are the best food sources of antioxidants.

Atkins himself knew that in his diet, you had no choice but to take supplements to have a chance of obtaining adequate nutrition. 

You might think this fact would be a problem for the Atkins people.  Far from it.  It creates an opportunity for them to sell supplements to the gullible people following their extreme diet.

Why would someone consider such a deficient diet?  It seems serious nutritional inadequacy is a pretty major flaw for a diet to have.  The research must say there are some really great benefits to low carb, high fat to overcome this, right?  I’ll show you lots of research into low carb soon and let you be the judge of that.

Low carbers imagine the body's metabolism is fragile, and easily broken by even the healthiest high-carb foods.  Somehow we are to believe that only some people can tolerate starches, for example, even though all the world’s population centers have historically eaten diets dominated by them. 

I have a hard time understanding how this type of reasoning makes it past the laugh test.  Here are some high carb Indians from around 1910.  Do they look overweight to you?

Here are some Fakirs from around the same time.  What about them?  What do you think they ate?  Now maybe they appear undernourished to you.  But the point is, carbs did not make them fat.  I found these pictures randomly, but you can easily go on Google Books and find many more old photos of people from high-carb cultures.  Good luck finding someone who looks fat.

Poor people in pretty much every society used to eat primarily starch-based diets.  Poverty has not been associated with obesity until recent times.  Of course, diet is only one factor in explaining this, but I would think the idea that carbs make you fat would be hard to accept for any rational person with a sense of food history.

On the other hand, low carbers tell us that somehow liberal amounts of fats, meats and oils can somehow promote weight loss.  It's hard to figure.

Who doesn't know that fats are the most calorie-dense macronutrient?  It seems this fact creates some difficult math to overcome for low carb promoters.  I'll talk about this more in the next section, but for now, let's look at the research out there for low carb diets. 

First, let's start with the basics.  It is the consensus view of obesity researchers that the most important factor for weight loss is creating a calorie deficit.  You need to use up more energy than you eat, simple as that.  The particular diet you use doesn't matter much as long as you create a calorie deficit.  If you need to lose weight and you do so successfully, you will be probably be at least a little bit better off regardless of your strategy.  Here, for example, no advantage was found for a high-protein diet.

No particular macronutrient balance was seen to have an advantage in this one, too. 

Have you ever noticed that people doing low carb diets can't stay with them very long?  They seem to fall off the wagon a lot more than vegans do.  This slide might give us an explanation for all that.  To stay on a diet you need willpower.  But to have willpower you need glucose.  Low carb aims to keep your glucose low, so you probably won't have much of a chance of sticking with it very well.  How ironic!

Adequate levels of blood glucose will also keep you from craving fatty, unhealthy, high-calorie foods, too.  If you are more likely to crave high calorie foods, you will probably have a harder time achieving and maintaining your optimum weight.  A dietary approach that endeavors to give you low blood sugar doesn’t seem like a great strategy for having a healthy long term relationship with food. 

As I said, you would think there must be some really great research out there that makes low carb look good.  The most important fact you need to understand about the favorable low carb studies is that all of them are short term.  Even a year- or two- year-long study is too short to show all the harmful effects of a diet.  The harm associated with high saturated fat consumption can take decades to build.  A short study won't show that. But make no mistake, there is a lot of research that suggests these diets are harmful over the long term. If you're a low carber, as I go through these studies, I'd like you to ask yourself: If all this negative research were about vegan diets instead of high fat animal food diets, wouldn't it make you question the safety of vegan diets?

High-fat diets are associated with brain aging...

and cognitive decline.  This study saw heart impairment as well.  There is also a lot of reason to worry about what these diets will do to your heart.  I'll show you what I mean in the Part II.


Primitive Nutrition 48:
Low Carb, High Fad, Part II


Let’s see what low carb can mean to your heart.

High fat diets are shown to be harmful to cardiovascular health in numerous animal studies.  Here in baboons, for example, a high-fat, high-cholesterol diet was shown to damage the ability of cells within arteries to the point they can't replicate.  This is called cellular senescence and it is a known cause of inflammation and aging.

High fat diets are known to hurt human arteries as well.  The health of the endothelial lining of the arteries is assessed through the measurement of flow mediated dilation.  Here in a comparison of different diets, only a diet high in saturated fats harmed this function.

Flow mediated dilation was also a problem in this low carb study.

In this one, low carb caused damage to heart metabolic function suggesting it could raise the risk of heart failure.

And in this one it hardened arteries.

We can also look at traditional measurements of heart health to see problems.  In this comparison of diets, only the high-fat diet increased LDL cholesterol.  This is a running theme for high fat diets.

In this year long study a high fat diet raised LDL and worsened a lot of other measurements, too.  Uffe Ravnskov should note the mention of fibrinogen.

The most famous low-carber, Dr Atkins had significant atherosclerosis at the end of his life.

With their lack of plant foods, low carb diets increase the chance of damage to your digestive system as well.

But the most concerning studies link low carb diets to an increased death rate.  This one really raised hackles among low carbers.  Diets based on animal foods and lacking in healthy carbs were associated with higher all-cause mortality.  Every conceivable objection has been raised.  They weren't really hard core low carbers, or they didn't eat the right animal foods, or the people in the study had bad memories, but really, those arguments are pretty weak, especially since there are other studies that have shown the same thing.

This study of Swedish women found higher mortality on low carb, too.

And so did this study of elderly Swedish men.  Think about how long it would take to complete a study that shows the effects of diet on mortality and you'll know why epidemiological studies like Ancel Keys' Seven Countries Study were and are necessary.  You can’t take people and put them in controlled lab conditions for decades. There will probably never be a perfect study assessing diet and mortality for this reason.  Low carbers will always have a way of dismissing a study if they want to.  That doesn't mean they are right.

High fat diets also seem to scramble our metabolism.  We can see metabolic dysfunction in people with normal metabolism but who are at risk of diabetes after only one meal.

And we can see in primates that a maternal high-fat diet causes metabolic dysfunction in offspring.

And here you see something similar in rodents.

And here, too.

There has been a lot of research into the effects of a high-fat diet on rodents.  Do your own search on "high fat diet" and "mouse" or "rat" and you'll see how much bad news is out there.  With lab animals, researchers can examine what a fatty diet can do in great detail. It seems no one is asking whether a fatty diet is harmful but rather how it is harmful.  This one got low carbers upset but you can see this is a very sophisticated study.  Impaired glucose-sensing was observed in these mice.

Here rats were fatter and more insulin resistant and generally more dysfunctional with higher fat consumption.

Here resistance to growth hormone was induced.

In this one a high fat diet reduced the activity of a gene controlling a key enzyme, setting the stage for dysfunction.

Here a high-fat diet caused insulin resistance and lessened fat-burning.

A high fat diet caused intestinal inflammation in these mice.

These rats were so damaged by a high-fat diet that when they went back to normal food, they gained more fat than they otherwise would have without actually eating more calories.  If it works the same way in humans, it's easy to imagine how a low carb fatty diet sets the stage for yo-yo weight-loss and gain, or weight cycling as it is properly named.

Weight cycling is likely harmful to both your physical and mental health.  It seems more efficient to skip the fad diets and adopt a healthy and sustainable lifestyle based on the best modern science.

I think you are getting the point, but here is just one more rodent study.  I like this article because it tells you why all these studies are done.  I doubt these studies are being funded to prove low carb is bad or fat is bad, and they are certainly not to figure out the best way to feed mice.  No, these are to develop new drugs to combat obesity.  Obesity represents a serious and growing public health concern, as well as an opportunity to create profitable therapies.  This researcher does acknowledge there might be a healthier solution than drugs.  He says a healthy diet is a noble thing to strive for.  After seeing all this research, it seems to me it's much more than that.  I'd say it's the only option if you want to have real and lasting good health.

If that is what you want for yourself, I'll show a you a better way to achieve that than low carb in the next video.

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