Superb Health

Dr. Lynch explains how to avoid common western disease with food.

 Research Article of the Month

July, 2009

Prepared by Shane J. Lynch, D.C.

Cordain L et al. Orgins and evolution of the Western diet: health implications for the 21st century. Am J Clin Nutr 2005; 81(2): 341-54.

The major premise of this article is that the majority of chronic diseases of Western civilization have emerged as a result of diet. The authors hypothesize that with the advent of agriculture, especially the industrial revolution approximately 200 years ago (y.o.), the corresponding change in food staples have been too much for our genome (i.e. exceeds the capabilities of our organs and glands) resulting in the emergence of chronic diseases in epidemic proportions. The authors go on to write that “in the U.S. and most Western countries, diet related chronic diseases represent the single largest cause of morbidity and mortality”. The authors specifically state that major changes in our food staples have had dramatic effects on 1) Glycemic index, 2) fatty acid composition, 3) macronutrient composition 4) micronutrient composition 5) acid-base balance, 6)sodium-potassium ratio and 7) fiber content.

1. Glycemic index
This is roughly a rating of how quickly individual foods can raise blood glucose (sugar) levels.
Some carbohydrates (sugars) in foods have the ability to raise blood glucose levels quicker than others. For example, refined grains (found in breads) and processed sugary foods and drinks have higher glycemic indices than unprocessed (no additives) fruits and vegetables.
Pre-agricultural populations consumed diets with low glycemic indices and the current over consumption of high glycemic index foods have lead to “physiologic changes that promote insulin (hormone released by pancreas in response to blood sugar; stimulates cell receptors to allow sugar to enter) resistance disease”.
Diseases of insulin resistance (AKA Disease of civilization) include: type 2-diabetes, obesity, coronary heart disease (CHD), hypertension and dyslipedemia (increased triglyacylglycerols, LDL=bad cholesterol and decreased HDL=good cholesterol).
What to do: Substitute processed grains (cereals, breads, bagels, chips, etc.) and sugary foods (candy, soda, sugar in coffee, doughnuts, etc.) with fruits, vegetables, water, tea and breakfast foods such as eggs.

2. Fatty acid consumption

There are three major categories of fatty acids (fats): saturated fatty acids (SFA), mono-unsaturated fatty acids and poly unsaturated fatty acids.
Current evidence suggest that decreasing dietary intake of certain fats while subsequently increasing the consumption of more beneficial fats is more important in disease prevention than avoiding fats all together. For example, SFA and trans fats “increase the risk of coronary vascular (CVD) disease by increasing blood concentrations of total and LDL cholesterol”. Omega 3 polyunsaturated (N-3) fats, on the other hand, decrease CVD by decreasing blood clotting, serum triacylglycerols (fat levels) and growth of atherosclerotic plaques, among other things.
Increased dietary intakes of N-3 fatty acids prevent and reduce progression of many inflammatory and autoimmune diseases.
Prior to development of agriculture, MUFA and PUFA’s dominated the diet; SFA were to a minimum.
The 6 major sources of SFA’s in the U.S. diet are fatty meats, baked goods, cheese, milk, margarine and butter.
The advent of the oil-seed processing (i.e. used to make cooking oils) industry at the beginning of the 20th century has increased our dietary intake of n-6 PUFA (inflammatory; not good in diet) at the expense of N-3 PUFA’s (anti-inflammatory; good in diet). Consumption of N-6 PUFA also increased during this time as livestock primarily were and still are raised on grains versus grass.
The current ratio of N-6/N-3 PUFA is ~10:1; hunter gathers had a diet estimated to be ~2.5/1.
The hydrogenation process, invented in 1897, introduced trans fatty acids to our diets, which increase blood cholesterol (LDL) leading to increased risk of developing CVD.
What to do: Avoid trans fatty acids, decrease saturated fat intake, and substitute salad dressings (high in N-6 PUFA) with olive oil and vinegar, for example.

3. Macronutrient consumption

Macronutrients in diet are carbohydrates, fat and protein. In America 51.8% of total food energy comes from carbohydrates, 32.8% from fat and 15.4 from protein.
Pre-agricultural diets were believed to be much higher in protein than they currently are.
High protein diets improve blood lipid (fat) levels, decreasing the risk of developing CVD. Furthermore, high protein diets have been shown to decrease blood pressure, improve insulin sensitivity (i.e. cells effectively respond to insulin) and prevent muscle loss.
Protein has a greater satiety (provides a sense of fullness) value than do fat or carbohydrates.
What to do: Increase consumption of lean meats (animals that are grass fed), leafy greens, mushrooms, eggs and decrease consumption of carbohydrates.

4. Micronutrient consumption

Micronutrients are vitamins and minerals.
Refined sugars contain no vitamins or minerals.
Overconsumption of refined sugars, grains, vegetable oils and dairy products has “considerable potential to influence the risk of vitamin and mineral deficiencies”.
At least ½ of the U.S. population fails to meet the Recommended Dietary Allowance (RDA) for vitamins B-6, A , magnesium, calcium and zinc.
33% of the U.S. population does not meet the RDA for folate.
Folate and B6, among other functions, decrease the development of CVD, strokes, and deep vein thrombosis.
The Neolithic (10,000-5,500 Y.O) introduction of dairy foods and cereal grains as staples in the diet, at the expense of lean meats and seafood has lowered our overall micronutrient consumption.
Consequences of low micronutrient consumption “promote the development of vitamin-deficiency diseases” and numerous “infectious and chronic diseases”.
What to do: Consume less refined sugars, grains, vegetable oils and diary products and at the same time increase your consumption of fruits, vegetables, lean meats and seafood.

5. Acid-base balance

“ After digestion, absorption, and metabolism, nearly all foods release either acid of bicarbonate (base) into the systemic circulation (blood)”.
Acidic foods: Fish, meat, poultry, eggs, shellfish, cheese, milk and cereal grains (Note, all protein foods are acidic).
Fruit, vegetables, roots and nuts are base producing foods.
Legumes (beans) are neutral.
Salt is net acid producing.
The typical Western diet is primarily acidic, which results in a “chronic low-grade pathogenic (disease producing) acidosis that worsens with age as kidney function declines”.
Virtually all pre-agricultural diets were net base yielding.
Health benefits of a net base yielding diet includes: prevention and treatment of osteoporosis, age-related muscle wasting, calcium kidney stones, hypertension, and exercise-induced asthma.
A net base producing diet also slows progression of age and disease-related, chronic renal (kidney) insufficiency.
What to do: Balance acid rich foods (i.e. high protein foods) with base producing fruits and vegetables.

6. Sodium-potassium ratio

Salt consumption in the U.S. significantly outweighs potassium consumption. This is attributed to high a reliance on processed foods (high in sodium), over consumption of vegetable oils and refined sugars (devoid of potassium) and displacement of fruits and vegetables with whole grains and milk products.
Between the Neolithic and Industrial period a 400% decrease in potassium intake and a 400% increase in sodium occurred.
Diets low in potassium and high in sodium may “partially or directly underlie or exacerbate a variety of maladies and chronic illnesses, including hypertension, stroke, kidney stones, osteoporosis, GI (gastrointestinal) tract cancers, asthma, exercise induced asthma, insomnia, air sickness, high-altitude sickness, and Menier’s syndrome (ear ringing)”.
What to do: Increase potassium consumption (fruits and vegetables) and decrease sodium intake (the best way to do this is to avoid prepackaged/processed foods).

7. Fiber content

“Refined sugars, vegetable oils, diary products and alcohol are devoid of fiber and constitute an average of 48.2% of energy in U.S. diet.”
“Fiber-depleted refined grains represent 85% of the grains consumed in the U.S.”
“Fresh fruit typically contains two times the amount of fiber in whole grains, and nonstarchy vegetables contain almost eight times the amount of fiber in whole grains”.
“Soluble fibers (those found primarily in fruit and vegetables) modestly reduce total and LDL cholesterol concentrations beyond those achieved by a diet low in saturated fat and fiber”.
Low fiber diets may “underlie and exacerbate constipation, appendicitis, hemorrhoids, deep vein thrombosis, varicose veins, diverticulitis, hiatal hernia and gastrointestinal reflux (cause of heartburn).

Summary

“In the U.S. and most Western countries, diet related diseases represent the single largest cause of morbidity and mortality”.
“The ultimate factor underlying diseases of civilization is the collision of our ancient genome with new conditions of life in affluent nations, including nutritional qualities of recently introduced foods”.