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Guide Index

A Feast at Plimoth

Feast or Famine

Truth or Consequences


Mushroom Mania

The Bite Stuff
in the classroom

ABOUT ALL YOU CAN EAT: Feast or Famine

One of the greatest mysteries of medical science -- the case of the Pima Indians -- may soon be solved. The Pimas (known by their traditional name as Akimel O'odham) of Arizona suffer from the world's highest rate of obesity and a disease often associated with it, diabetes. Scientists suspect that a gene may predispose them to obesity, but life-styles and eating habits may also be at fault. Close relatives living in Mexico provide the ideal control group for researchers to test their theories.

Curriculum Links
Activity: Testing a Theory
Corn in the Life of a Hopi



genetics, respiration

calories, energy consumption

Hispanic culture

calorie physiology,
plant biology


diet and nutrition,

disease, metabolism

energy conversions

agriculture, Mesoamerica,
Native Americans


Mesquite and cactus may not have much appeal for people accustomed to contemporary American diets, but for some Native Americans, these plants may be lifesavers.

Ethnobotanist Gary Paul Nabhan has been working for many years with the Akimel O'odham, the same group in the Frontiers story. The Akimel and the Tohono O'odham (formerly Papago), share a heritage that includes a diet of desert plants. Some scientists are investigating the value of these plants in controlling obesity and diabetes. Some studies have shown that a return to low-fat, high-fiber plant foods such as cactus, grains, certain beans, even tumbleweed, can lower cholesterol and help control blood sugar levels.

Nabhan theorized that as the two groups of Native Americans adapted to a high-fat, low-fiber Western diet, they gained weight and many developed adult-onset diabetes. He decided to set up an experiment to see if returning to their ancient diet and earlier levels of daily exercise would help the Akimel and Tohono O'odham regain their health.

CHALLENGE: How would you set up an experiment to test Nabhan's theory?
  1. How many different groups of people would you need? Would all the groups eat the same diet or would some continue on the high-sugar diet?

  2. If you believed that the current high-sugar diet was not healthful for people with diabetes, could you ethically ask them to continue it for the experiment?

  3. What information must you always give people who participate in experiments?

  4. If you wanted to see if the diet and the exercise each worked independently from one another, how would you structure the experiment?

  5. Do you have a theory about weight and/or exercise? How would you design the experiment?

Notes: Both Nabhan and the scientists seen on Frontiers are working with groups of Native Americans to try to solve serious health problems. Scientists investigate problems from different angles and look at all facets of a situation. Related topics of discussion might include: ethnobotany, diabetes and the value of such studies for society. You might also want to look at how experiments are set up in the other stories in this episode of Frontiers.


"When a child was born, his Corn Mother fetish was placed beside him, where it was kept for twenty days, and during this period he was kept in darkness . . . Early on the morning of the twentieth day, the mother, holding the child in her arms and the Corn Mother in her right hand, and accompanied by her own mother -- the child's grandmother -- left the house and walked to the east. They stopped, facing east, and prayed silently, casting pinches of cornmeal to the rising sun. When the sun cleared the horizon the mother stepped forward, held up the child to the sun, and said, 'Father Sun, this is your child.'"
-- from The Native Americans: An Illustrated History (Turner Publishing, 1993)

Corn held a central significance for the Hopi, as it did for many Native American tribes. As anthropologist Sol Katz demonstrates in "Superfoods," another story in this episode of Frontiers, Native Americans figured out how to unlock the nutrition in corn by processing it with an alkali. Secrets of the alkali processing were known to the Hopi and Zuni tribes, descendants of the Anasazi. The O'odham groups are believed to be descended from the Hohokam, who grew drought-resistant corn thousands of years ago in the desert.

(For more activities and facts about corn, see Superfoods in this guide.)


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.