Our Evolutionary Past
Our dietary requirements are a legacy of our evolutionary past. Our Early ancestors
who roamed the grasslands and savannahs gathering vegetables, fruits, legumes,
and nuts evolved a fast metabolism based on carbohydrates. Those who lived in cold
climates and relied on hunting developed a slower metabolism based on fatty meats.
Still other early ancestors evolved in temperate climates and developed a metabo-
lism for a hybrid diet of both meat and vegetation. The agricultural revolution that
occurred 6,000 years ago added grains and dairy products, and has recently been
followed by the industrial revolution whereby both food and the environment are be-
ing modified at an ever increasing pace. During this moment in evolution, the three
metabolic types remain essentially unchanged.
Carbohydrate / Fat / Protein Ratios
The importance of the percentage of calories coming from carbohydrates, fats, and
proteins was established by the Senate Dietary Goals (SDG), a panel of experts ap-
pointed by congress. The SDG diet recommends 58% carbohydrates, 30% fat, and
12% protein. The typical American diet consists of 46% carbohydrates, 42% fat, and
12% protein. The SDG diet also recommends natural carbohydrates, whereas the
typical American diet emphasizes refined carbohydrates. The SDG diet corresponds
to an intermediate metabolism; small adjustments to the SDG in carbohydrate and
fat percentages serve the other metabolic types.
Primitive vs. Modern Diets
The starting point for balanced nutrition is a comparison of modern vs. primitive diets.
The ratio of sodium to potassium has incresed 64-fold from 1:4 to 16:1; the ratio of sat-
urated to unsaturated fats has increased 9-fold from 1:3 to 3:1. The primitive diet had
ten times as much vitamin C and six times as much fiber as a modern diet. Modern
modes of transportation make food available year-round with the result that people
eat tropical fruit in winter, a metabolic mismatch. Chemicals, preservatives and re-
fining processes have promoted an abundance of food at the price of reduced den-
sities of nutrients. Furthermore, carbohydrates yielding only empty calories are con-
sumed in far greater quantities than in any primitive diet. It is imperative to account
for both the past and present environments, modern nutrients, and metabolic types to
achieve balanced nutrition.
The nutritional guide gives guide lines for developing a balanced diet that is healthy
and nourishing. Several references to balancing diets are in the Reference link.
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