Low Grain Carbohydrate Diets Treat Hypoglycemia, Heart Disease, Diabetes Cancer

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Low Grain and Carbohydrate Diets Treat Hypoglycemia, Heart Disease, Diabetes

Cancer and Nearly ALL Chronic Illness.

by Joseph Brasco, MD

 

 

Unfortunately, the debate over the validity of this concept has primarily been

waged in the media and lay publications and not in the scientific journals. Many

of the popular books which support this position are gimmicky, and often, lack

adequate scientific referencing. Yet, at their core is very important concept --

limiting the intake of carbohydrates, (especially as cereal grains and

starches), will improve human health.

 

Some critics claim that reduced carbohydrate diets are a fashion trend. Well,

this so called trend actually dates back some time. Anthropological study of

early hominids has concluded that they lived as hunters-gathers. While nuts,

seeds, vegetation and fruit made up an important part of the hunter- gather's

diet, his mainstay was hunted or scavenged animal prey.

 

More recent evaluations of early man's nutritional patterns by Dr. Loren

Cordain, estimate that as much as 65 percent of his calories were derived from

animal products. Granted, early man was not eating corn fed Angus beef from

Jewel, but he was eating the meat, the organs and the bones of his prey.

Essentially, a high protein/fat diet. It was a mere 10,000 years ago (or less)

that man began exploiting an agricultural niche.

 

This transition was made due to decreasing population of large game prey and an

increasing population of humans. While undeniable good has transcended this

dietary shift, i.e., growth of the human population, establishment of permanent

settlements, the inception of civilization itself - man's health may have

suffered in the transition.

 

Generally, in most parts of the world, whenever cereal-based diets were first

adopted as a staple food replacing the primarily animal-based diets of

hunter-gatherers, there was a characteristic reduction in stature, a reduction

in life span, an increase in infant mortality, an increased incidence of

infectious disease, an increase in diseases of nutritional deficiencies (i.e.,

iron deficiency, pellagra), and an increase in the number of dental caries and

enamel defects.

 

In a review of 51 references examining human populations from around the earth

and from differing chronologies, as they transitioned from hunter-gathers to

farmers, one investigator concluded that there was an overall decline in both

the quality and quantity of life.

 

There is now substantial empirical and clinical evidence to indicate that many

of these deleterious changes are directly related to the predominately

cereal-based diets of these early farmers. Since 99.99% of our genes were formed

before the development of agriculture, from a biological perspective, we are

still hunter-gathers.

 

Thus, our diet should reflect the sensibilities of this nutritional niche: lean

meats; fish; seafood; low glycemic vegetables and fruit, (modern agriculture has

significantly increased the sugar and starch content of vegetables and fruits

over their Paleolithic counterparts), nuts and seeds - the evolutionary diet.

 

Glycemic Index

 

The term glycemic index, (GI) (a qualitative indicator of carbohydrate's ability

to raise blood glucose levels), has seen a lot of mileage among the many

non-ketogenic low carbohydrate diets. Most of these diets attribute the rise in

obesity to the over consumption of high glycemic carbohydrates, and the

subsequent over production of insulin.

 

While this may be an oversimplification, there is growing evidence to support a

relationship between GI and non-insulin dependent diabetes (NIDDM), and obesity.

In a prospective study of 65,000 US women, researchers were able to demonstrate

that the dietary GI was positively associated with the risk of NIDDM.

 

The authors concluded that diets with a high GI increase insulin demand and thus

cause hyperinsulinemia among patients with NIDDM, as well as in normal subjects.

If chronic, this hyperinsulinemia can increase the risk for, as well as

exacerbate NIDDM.

 

The issue of carbohydrates and insulin has more recently been addressed in a

review article by Grundy. Grundy states that because secretion by pancreatic

beta-cells is glucose sensitive, a high intake of carbohydrates has been

reported to produce higher post prandial insulin levels. Moreover, it is

possible that repeated stimulation of a high insulin output by high-carbohydrate

diets could hasten an age-related decline in insulin secretion and lead to an

earlier onset of NIDDM.

 

However, chronic hyperinsulinemia is not only associated with NIDDM, but is also

related to a host of other medical conditions jointly known as Syndrome X. The

constellation of disorders comprising Syndrome X include hypertriglyceridemia,

increased LDL cholesterol, decreased HDL cholesterol, hypertension,

hyperuricemia and obesity.

 

If high GI carbohydrates in fact contribute to chronic hyperinsulinemia as

multiple studies suggest, they are likely to be causative of these other

conditions as well. In addition to their role in hyperinsulinemia, studies have

also linked high GI foods with overeating.

 

One study found an inverse relationship between satiety and both glycemic and

insulin index. In another study,it was found that voluntary energy intake after

a high GI meal was 53% greater than after a medium GI meal and was 81% greater

than after the low GI meal. The authors concluded that a high GI meal promotes

excessive food intake in obese subjects. The literature clearly points to a role

of high GI carbohydrates in the development of insulin resistance and its

subsequent disorders.

 

However, GI is obviously not the whole story. One researcher examined the

insulin demand generated by isoenergetic portions of common foods. While some of

the results were predictable, i.e., the fact that glucose and insulin sources

were highly correlated, some were unexpected, i.e., some protein-based foods

induced as much insulin secretion as did some carbohydrate rich foods. At first

glance, these results seem confounding. However, if one looks at the broader

function of insulin, they are consistent.

 

Insulin is not just responsible for glucose disposal, but for storage and uptake

of multiple nutrients. Whether these other nutrients can result in a chronic

hyperinsulinemic state, as seen with high GI diets, is not known; it is unlikely

due to their compensatory effect on glucagon. The other major difference between

the insulin response of other nutrients versus carbohydrate is their effect on

blood glucose.

 

While protein and fat stimulate insulin response, their effect on glucose is

minimal. This lack of effect on blood sugar is more than trivial difference. It

actually may be the glycosylation of end organs (especially the pancreatic

beta-cells) that ultimately leads to NIDDM and its associated conditions. Thus,

while a hyperinsulinemic state is not desirable for human health under any

circumstance, the combination of hyperinsulinemia with impaired glucose

homeostasis is likely to prove even more deliterious.

 

While the current literature would support limiting the consumption of high GI

foods, GI certainly does not provide the final answer. If one was to follow this

concept literally (as some popular books suggest) one could argue that potato

chips at a GI of 50-59% were more beneficial than carrots at a GIU of 90-99%.

 

A better way of looking at carbohydrates is to return to the principles of the

" evolutionary diet. " Robert Crayhon, M.S., author and champion of the

" Paleolithic diet " , divides carbohydrates into two basic groups, paleocarbs and

neocarbs. Paleocarbs include vegetables, fruits and perhaps tubers. Neocarbs

(carbohydrates introduced within the last 10,000 years or less), include grains,

legumes, and especially flour products, which did not exist for most of human

history.

 

The worst of the neocarbs include sugar and white flour products. If we follow

the simple guidelines of restricting ourselves to paleocarbs, we will in general

be eating fiber rich, nutrient dense, low glycemic carbohydrates, the best

nature has to offer.

 

Epidemiological Data

 

Another argument against carbohydrate restriction is based on epidemiological

evidence, and the Pima Indians are frequently cited. The Arizona Pima Indians

have received the attention of the medical community because of their prodigious

rates of obesity, which is nearly 70% among the adult population. Along with the

reputation of being one of the most obese people known, the Arizona Pima has a

rate of diabetes 8 times the national average with nearly 50% of the adult

population over 35 afflicted with this condition.

 

In spite of innumerable studies, examining the Pima from every imaginable

vantage point, there has been no defining discovery explaining the Pima's

plight. One hypothesis favored by Eric Ravussn, Ph. D, is that after generations

of living in the desert, the only Pima who survived famine and drought were

those highly adept at storing fat in times of plenty. These " thrifty " genes

which once ensured the Pima's' survival are now at the root of his demise.

 

Although it is not known for certain what metabolic processes these " thrifty "

genes control, insulin resistance and glucose homeostasis are thought to be at

the heart of the matter. Since preagricultural, man's diet was primarily derived

from animal sources (protein/fat), an insulin resistant genotype would have

minimized glucose utilization and thus, proven to be of an evolutionary

advantage.

 

As primitive peoples have become acculturated and have assumed a modern diet,

the constant supply of highly refined, high glycemic index carbohydrates has

resulted in postprandial hyperinsulinemia and the subsequent diseases associated

with this condition i.e. obesity, diabetes, cardiovascular disease, etc.

 

The Arizona Pima's diet prior to acculturation was essentially that of a

hunter-gather with some subsistence farming: (chollacatus buds, honey mesquite,

poverty weed, prickly pears, mule deer, white-winged dove, black-tailed

jackrabbit, squawfish, and they raised wheat, squash and beans). However, by the

end of the second World War, the Pima had almost entirely left their traditional

lifestyle and adopted the typical American diet.

 

There are many problems with the typical American diet, and to blame the Pima's

situation on just one element of that diet would be disingenuous. However, given

the current scientific and anthropological studies, one could suggest that the

high availability of sugar and highly refined, high glycemic carbohydrates (i.e.

neocarbs), are at the core of the Pima's health crisis. It could also be

extrapolated that, while the Pima's " thrifty " genes may work at a more

accelerated pace, it is the same set of genes interacting with the same diet and

producing the same results in the average American.

 

In 1991, the Pima's story became even more interesting. Peter Bennett FRCP, the

lead epidemiologist studying the Arizona Pima, discovered in Sierra Madre,

Mexico, the remnants of a tribe that once comprised the Southern half of the

Pima Nation. However, unlike their Northern brothers, the Mexican Pima remained,

in general, unacculterated and living a traditional lifestyle.

 

Also, unlike their northern counterparts, the Mexican Pimas were not obese, nor

did they share in the Arizona Pima's high rate of diabetes and degenerative

diseases. This dichotomy has been termed the " Pima Paradox. " Since the Mexican

Pima consume a diet comprised mostly of beans, potatoes, corn tortillas and the

occasional animal product, (i.e. chicken) , this has often been used as the

epidemiological case study for the benefit of high carbohydrate diets in obesity

management.

 

However, two issues confound this example. First, on average, the Mexican Pima's

have 23 to 26 hours/week of occupational physical activity versus the Arizona

Pima's 5 hours or less. Certainly, such high levels of activity could mitigate

the hyperinsulinemic effects of the Mexican Pima's diet.

 

The second issue is the " Enigma " within the " Paradox " . Although the Mexican Pima

does not have the health issues of the Arizona Pima, they still have a

prevalence rate of diabetes at 6.4% (approximately 1.5x greater that the non

Pima Mexicans), and a 13% incidence of obesity among the adult population.

 

While these numbers are impressive compared to the US population, and stellar

compared to the Pima population, the question remains why should an essentially

unacculturated population performing on average 23-26 hours of physical labor

per week have any incidence of diabetes or obesity.

 

When modern day hunter-gatherers were studied by anthropologists, incidence of

these conditions were non existent, even among the eldest members of tribe. The

" evolutionary diet " model would thus suggest, in spite of their improved health

over the Arizona Pimas, the Mexican Pimas are still consuming a less than

optimal diet.

 

Although conclusions drawn from epidemiological data can sometimes be

misleading, the real message that can be taken from the Pimas is that as a

species we have proclivity towards obesity, a proclivity that will vary based on

our genetic stock.

 

This genetic predisposition, while multifactorial in nature, probably centers

around insulin resistance and glucose homeostasis. Since our preagricultural

ancestors did not have ready access to simple carbohydrates, fats were the

preferred source of caloric energy, and glucose conservation was evolutionarily

advantageous.

 

In modern times, the detrimental combination of low physical activity,

hypercaloric intake, and over consumption of neocarbs is at the root of our

obesity crisis. A return to an evolutionary based diet - lean meats, seafood,

fish, vegetables, fruits, (raw) nuts and seeds and moderate physical activity,

will ultimately be the cure.

 

Health Risk Associated with reduced Carbohydrate Intake

 

Another argument against carbohydrate restriction focuses on the purported

health risk of this dietary approach. Of the three macronutrients, protein, fat

and carbohydrate, it is only carbohydrate that is nonessential to the human

diet. Humans can exist for extraordinarily long periods of time without

carbohydrate consumption as long as essential protein and fat needs are met. It

is thus perplexing why nutritional dogma ascribes so many risks to the

restriction of this non-essential nutrient.

 

Ketosis

 

Ketosis is a natural physiologic state induced during prolonged states of

decreased glucose availability. It is triggered by severe coloric restriction or

when carbohydrate intake falls below 20-30 grams, (most of the current low

carbohydrate diets are nowhere near this level of restriction).

 

In ketosis, a set of elaborate metabolic processes occur which have the net

result of decreasing insulin secretion, increasing glucagon secretion, switching

off glycolysis, turning on lipolysis, switching muscles from glucose to almost

entirely fatty acids for fuel, and ultimately providing ketone bodies (produced

in the liver), markedly diminishing the need for glucose by the brain in

particular and the body in general.

 

Ketosis was an absolutely vital survival mechanism for early man. It allowed him

to survive periods of starvation as well as long periods of carbohydrate

deprivation. Despite the role ketosis plays in normal human physiology, its'

modern application has often been portrayed with multiple negative health

connotations.

 

However, both scientific and epidemiological data has failed to justify these

concerns. The ketogenic diet has been used for nearly 70 years to treat

refractory seizures in the pediatric population. Multiple recent studies have

described nutritionally balanced, food varied versions of this diet.

 

One investigator looked at the health profiles of adults who had been treated

during childhood with ketogenic diet. He found no evidence of adverse effects on

cardiovascular function, including arteriosclerosis, hypertension or cardiac

abnormalities. Blood cholesterol determinations were performed on these adults

and all were normal. These studies thus fail to reveal any short term

complication or long term sequelae associated with ketogenic diets.

 

In the mid twenties to late thirties, the famed anthropologist V. Stefansson

chronicled the life and culture of the Eskimo in a series of books and journal

articles. Of the many observations made by Stefansson, he was most intrigued

with their diet and health. In spite of a nearly 100% animal based diet, the

Eskimo people enjoyed an excellent state of well being and a freedom from many

western diseases.

 

This observation was greeted with a high degree of skepticism in a scientific

community that was becoming increasingly hostile toward the role of protein and

fat in the American diet. To silence his critics, Steffansson devised a study

whereby he would consume an all meat diet for one year.

 

Under observation at Bellvue Hospital in New York City, Stefansson and a

colleague did in fact consume for one year an all meat diet. At years end, to

the surprise of the scientific community, both investigators were in excellent

health. They demonstrated weight loss with reduction in body fat, normal kidney

and liver function, and improvement in blood lipids (within the limits of

diagnostic testing of the time).

 

The " Bellvue ward study " created quite a stir in the scientific community and

was detailed in numerous articles appearing both in popular and professional

literature. Although long term commentary cannot be made, this remarkable study

certainly speaks to the short term safety of a ketogenic diet. Ample scientific,

epidemologic and anthropological data exists to support the general safety of a

ketogenic diet. However, this data does not exonerate all the modern inceptions

of this diet.

 

Traditional cultures who consumed a largely animal based diet, derived a great

deal of their vitamins and nutrients by consuming the organs, eyes, glands and

gonads of their prey. Modern ketotic diets are primarily based on common

American foods, i.e. meats, eggs and cheeses. They do not qualify the source of

animal products (i.e. salmon versus bacon), and are usually overloaded with

salt. In general, these diets are only concerned about limiting carbohydrate

intake without overall regard to food quality.

 

In the most popular version of the ketogenic diet, Dr. Atkins New Diet

Revolution, Dr. Atkin's writes " at the other end of the spectrum is a

convenience food that sounds terrible fatty, but in fact, contains nearly none.

Those are the maximizers of crispness - fried pork rinds - the zero carbohydrate

consolation prize for corn or potato chip addicts. Virtually all the fat has

been rendered off, leaving you with the protein matrix that held the pork fat

together. Your pate, sour-cream based dips and guacamole find an exceedingly

crisp and comfortable home atop a fried pork rind.

 

In spite of their potential physiologic benefits, the modern ketogenic diets

with their unbalanced, nutrient poor and often absurd dietary suggestion are

difficult to support. However, ketogenic diet based on evolutionary appropriate

foods would be interesting to pursue in clinical practice.

 

Lack of fruits, vegetables and grains Aside from the ketogenic diets, most other

reduced carbohydrate programs allow for the ample consumption of vegetables and

the modest consumption of low glycemic fruit, (the best sources of nutrients and

phytonutrients available to man).

 

Of the major carbohydrate sources mentioned, only grain is heavily restricted.

Although present diet dogma portrays grain as the quintessential food source,

(it is at the base of the food pyramid after all), many nutritional scientist

have called this assertion into question. In a work of prodigious proportions

(342 literature citations), Dr. Loren Cordain examines mans double edged

relationship with grain.

 

On one hand man is utterly dependent upon grain as a primary caloric source and

yet grain may be at the core of many of our common maladies. As would be

predicted by the evolutionary diet model, Dr. Cordain concludes that grain is

biologically novel to the diet of mankind as it was introduced as a staple food

only 10,000 years (or less) ago. Due to its relatively recent introduction, our

species has not fully adapted physiologically to its digestion and metabolism.

 

In spite of the impressive nutrient profiles of grain, the vitamins and minerals

often occur in forms that have low bioavaildality to the human digestive tract.

In addition to these poorly utilizable nutrients, grain contains many secondary

metabolic components commonly categorized as anti-nutrients.

 

Anti-nutrients are chemical compounds naturally occurring in grains, which

evolved to protect the plants from predators. Processing and cooking does not

not fully rid the grain of these elements, thus making them prominent in our

diet. Recent scientific study has linked these anti-nutrients to a number of

negative biological consequences which include: allergen based disorders;

pancreatic hypertrophy and disruption of the gut cell wall tight junctions (thus

exposing the systemic circulation to food allergens and gut flora).

 

One of the most curious of these negative processors associated with grain

anti-nutrients is a phenomenon known as molecular mimicry. Molecular mimicry is

when a similarity of structure is shared by products of dissimilar genes. When

this phenomenon occurs within the human body, the potential for developing an

autoimmune reaction is created.

 

The main body of evidence implicates viral and bacterial pathogens as initiators

of cross-reactivity and autoimmunity. However, there is an emerging body of

literature supporting the view that dietary antigens including cereal grains may

also induce cross-reactivity and hence autoimmunity by virtue of peptide

structures homologous to those in the host.

 

The diseases that may share this common origin are numerous and varied. They may

include everything from aphthous ulcers (canker sores), to rheumatoid arthritis

to non-insulin dependent diabetes to multiple sclerosis. While many of these

assertions may seem preposterous to a society reared on grain, evolutionary

pressures would suggest otherwise. The primate gut was initially adapted to both

the nutritive and defensive components of dicotyledonous plants rather that the

nutritive and defense components of mono- cotyledons cereal grains.

 

Consequently, humans, like other primates, have had little evolutionary

experience in developing a physiology that can both fully utilize and defend

against the compounds which naturally occur in cereal grains. So, while the

motives for limiting grains may be completely unrelated, many of the popular

incarnations of reduced carbohydrate diets may be paying their readers a great -

albeit - indirect service.

 

Continued on Page 2

 

 

 

 

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