Chapter Introduction

1

THE SCIENCE AND SCOPE OF NUTRITION

image
Exploring the Science of Nutrition A NEW FIELD IN NUTRITION RESEARCH IS REVEALING SURPRISING DETAILS ABOUT HOW FOOD AFFECTS OUR GENES. Natasha Vasilijevic/Gallery Stock

LEARNING OBJECTIVES

  • Define the scope and science of nutrition (Infographic 1.1)

  • Explain the connection between nutrition and chronic disease (Infographic 1.2)

  • Define and identify the major macronutrients and micronutrients (Infographics 1.3 and 1.4)

  • Summarize the purpose of the Dietary Reference Intake (DRI) values (Infographic 1.5)

  • Distinguish between the different types of DRI values, and what each represents (Infographics 1.6 and 1.7)

  • Understand/explain the basis of the scientific method and how it is used in nutrition research (Infographic 1.8)

  • Describe three types of experimental design and the primary advantages of each (Infographic 1.9)

  • Describe reliable sources of nutrition information (Infographic 1.10)

It was the final months of World War II, and the Dutch people were starving. As a last-ditch effort to hold on to the Netherlands, the Germans had blocked the transport of food from rural areas to western cities. By February, people were eating only a few hundred calories per day, typically a couple of small slices of bread and potatoes. Some people used paper to thicken soup. This period, now known as the Dutch Hunger Winter, lasted from October 1944 until the Netherlands was liberated in May 1945.

Thirty years later, a husband and wife team of scientists at Columbia University decided to investigate whether these extreme nutritional conditions had any long-lasting effects on the Dutch people.

After examining Dutch army records from 300,000 19-year-old men born around the time of the famine, the researchers made a startling discovery.

They found that men whose mothers endured the famine during the first months of their pregnancy were significantly more likely to be obese. But men whose mothers starved during the last months of their pregnancy, and into the first months of their life, were less likely to be obese. The explanation for this pattern wasn’t clear—but it appeared as if a woman’s diet during pregnancy could potentially have a strong influence on the weight of her future children.

image
Surviving World War II. An emaciated Dutch boy, Netherlands, circa 1944.
Hulton Archive/Getty Images

Other research soon followed. In the late 1980s, scientist David Barker, MD, PhD, found that babies with low birth weight were more likely to develop heart disease later in life—a finding that helped generate the “developmental origins hypothesis,” which states that certain diseases originate from conditions during pregnancy and infancy. Specifically, poor nutrition during that crucial time can permanently affect the way the baby’s body responds to food throughout his or her life. Subsequent research has also shown that a woman’s body weight and diet at the time of conception affects the health of her babies.

Prompted by these findings, nutrition scientists were asking many new questions about how food and nutrients affect the body. Could a mother’s nutrition have such long-lasting effects on her unborn child? Are we not, as the common phrase states, what we eat?—are we also what our mothers ate? And if so, how was this effect carried out in the body?

■ ■ ■