History of Research at the
U.S. Department of Agriculture and Agricultural Research Service
Founding
American Nutrition Science
|
Back to
Features
Watch a video to learn about this and other
discoveries that improve our daily lives.
Today's simple food charts aim to help everyone eat well.
|
In early 1893,
the odds that Wilbur Olin Atwater would get public support for his grand plan
for food investigations were slim to none. In fact, the future of the Office of
Experiment Stations, which he had worked so hard to establish, was in doubt.
But as often happens to people of vision, an angel
intercededin the form of a close personal friend of the Secretary of
Agriculture who knew and admired Atwater.
On May 23, the Secretary wrote: Mr.
Edward Atkinson of Boston suggests the expediency of establishing food
laboratories ....
With those simple words, the door was pried
open for the first federal funding of human nutrition research in the United
States. Although it took another year of intensive skirmishing and skillful
diplomacy, Atwater's efforts paid off. In May 1894, the agricultural
appropriations bill included $10,000 for food investigations.
Today, we take for granted federal funding
of nutrition research. In fact, in FY 1992, federal support of all U.S.
Department of Agriculture activities in human nutrition research was about $82
million; nearly $200 million was spent on nutrition education and information
programs.
And these figures do not include nutrition
programs in other federal departments such as Health and Human Services. But in
the 1890's, nutrition studies were quite new in the United States, and most of
them were being done by Atwater himself.
It is scarcely 50 years since the
classical researches of Liebig [the renowned German chemist] began to pave the
way for finding practically everything we know today of the ingredients of our
food materials, the way in which they are used in the body, and the kinds and
combinations which are best adapted to health and purse. Nearly all of the best
experimental inquiry in these lines has been carried on in Europe, wrote
A.C. True in introducing the first of Atwater's landmark publications, Bulletin
No. 21, shortly after the new funding was granted.
Knowledge of the nutrients and their
functions was very limited. Carbohydrates and fat provided energy to maintain
body temperature and do muscular work. Protein had the added duty of building
and repairing tissues. Vitamins were unknown. And only a few major minerals,
such as calcium and phosphorus, were recognized as somehow essential, but their
role in the body was unclear.
Atwater's quest for a scientific
understanding of nutrition was coupled with the social consciousness of the
day. In a 1894 letter, he wrote: The individual man is coming to realize
that he is his brother's keeper, and that his brother is not only of his
household but may live on the other side of the world. With all these
thoughtful people the conviction is growing that there is one fundamental
condition of the intellectual and moral elevation of the poor, the ignorant,
the weak, the destitute, namely the improvement of their physical
condition.
|
View related
stories:
Prospecting for
Health Protectants in Soy
Nutrition for
the Very Young
|
Atwater joined
the thinkers of the day in the conviction . . .that the intellectual and
moral condition and progress of men and women is largely regulated by their
plane of living; that the plane of their intellectual and moral life depends
upon how they are housed and clothed and fed.
A Man of Action
The son of a Methodist minister, Atwater was
born in Upstate New York on May 3, 1844, but was reared in Vermont. He attended
the University of Vermont for 2 years and graduated from Wesleyan University in
Middletown, Connecticut.
After a short period as a schoolteacher and
principal, he entered Yale University's Sheffield Scientific School, where his
interest in agricultural chemistry was kindled. For his doctoral thesis,
Atwater made the first modern analysis of a foodin this case, feed
cornin the United States.
With the ink still fresh on his doctorate,
he set out for Leipzig and Berlin to study physiological chemistry with the
masters. During his 2 years abroad, he became familiar with European
agricultural experiment stations. This spurred him to campaign actively for a
similar scientific program in the United States.
Two years after returning home, he found his
way back to his alma mater and remained at Wesleyan University until his death
in 1907. But he didn't teach much at Wesleyan; research was his love. Atwater's
son recalled that his father was threatened with having his salary cut in half
if he persisted in outside experiments.... However, he was given
the alternative of hiring a teaching assistant at his own expensewhich he
did.
One experiment Atwater did not plan occurred
accidentally while he was in Parisin early 1893, and it illustrates his
equanimity. He related the episode to his close friend and colleague C.D. Woods
back in Middletown:
You know I have long wanted to know
the action of ptomaines from the flesh of fish. In accordance with my usual
theory that the best way to learn is by practical experiment, I have been
eating fish with the ptomainesat least that is what the doctor
says.
|
These two-dimensional drawings represent foods that mound on a plate, such as
casseroles, vegetables, or rice. The plate and knife provide a size reference.
|
Literally from the crown of my head to the sole of my feet I
have been covered with swelling and blotches, feel as big as an ox, have a
color approaching that of beefsteak, and a variety of aches and bruises which
have left me with no lack of entertainment.... I think this one experiment will
suffice of the demonstration.
Even under duress, Atwater showed good
humor, though quite dismayed that the illness took ten precious days out
of my working time. He was a man of action.
As a special agent for USDA, he scouted top
European laboratories and solicited articles and abstracts from the foremost
researchers in agricultural and human nutrition studies. These would be
translated and printed in the Experiment Station Record, one of three
periodicals Atwater began as director of USDA's Office of Experiment
Stations.
With utmost courtesy, Atwater badgered the
European heavyweights for articles, abstracts, and answers. He wanted to
lift the Record and Bulletins to a higher scientific level, he wrote to a
USDA contact. These publications were intended to inform researchers in the
fledgling stations about the state of physiological research and guide them in
designing their own studies.
But Atwater was aiming even higher. My
opinion, he noted, is that we are in a fair way to make the Record
and Bulletins the best publications of their kind in any language, and that if
we keep on improving they will come to be recognized as such.
His leadership had been a major factor in
getting Congress to provide $15,000 annually to each state and territory for
the support of agricultural experiment stations. In fact, Atwater served as the
first director of the new Office of Experiment Stations, on the condition that
he could continue his research as professor at Wesleyan and director of the
state station at Storrs, Connecticut.
When the workload grew to require full-time
management in 1891, Atwater resigned his positionbut not his mission. In
fact, his life's calling was just beginning to crystallize. He began
formulating plans for comprehensive studies of the chemical composition of
foods, the effects of cooking and processing on nutrient content, the amount
and types of food consumed by different groups of Americans, and the amount of
energy (calories) people burned each day and thus needed to replace. He focused
on soliciting funds to support this research. After all, these were uncharted
waters, and there was no guarantee that USDA would come through.
|
Science supports grandmother's advice that oats are good for you-they can help
lower cholesterol levels.
|
So Atwater
talked nutrition to church groups, businessmen's clubs, wealthy potential
patrons, and government officials, notes Ross A. Gortner, Jr., a
successor of Atwater's at Wesleyan University. On many occasions, he
financed the purchase of new equipment out of his own pocket. His staff, too,
shared his enthusiasm and at times carried on their share of the work knowing
that there might not be funds to cover their salaries.
Atwater even succumbed to showmanship. In
October 1893, at the Chicago World Fair, he assembled l6 chemists who prepared
and analyzed food before wide-eyed onlookers. The demonstrations stirred public
interest and no doubt gave nutrition research a big push.
Atwater's most persistent trait was
persistence itself. He did not become the father of American nutrition on
intellect, charm, and vision alone. He simply never gave up.
In the 10 years that Atwater headed the
federal nutrition program, he conducted or coordinated research in four
areas:
- Types and amounts of foods consumed by
different groups.
- Chemical composition of foods.
- Effects of cooking and food processing on
nutritional quality.
- Amounts and types of nutrients people need
to function at their best; this entailed studies of human metabolism and
respiration.
The fact that these four research areas are
still pursued actively today is testimony to Atwater's vision. He could not
have imagined the scale or scope of today's research, but he would have
applauded the emphasis on maintaining health through a good diet. The following
sampling of today's research at the five human nutrition research centers under
USDA's Agricultural Research Service attempts to bridge the gap between then
and now.
Atwater oversaw more than 300 food
consumption studies of families and institutions in 17 states, involving more
than 10,000 men, women, and children. These included students, college
athletes, the families of professional men, mechanics, farmers, and laborers,
in widely separated states and of diverse ethnic groups.
|
Nutritionist Margaret Bogle talks about the importance of eating fresh
vegetables with students.
|
Concerned
about the nutrition of the poor and disadvantaged, Atwater supervised intake
studies of black sharecroppers, Mexican families, poor whites, and inmates in
state mental institutions. His observations ring true even today: The
differences in diet. . . are influenced, to some extent, by race habits, and to
a still larger extent, by the material conditions of the consumer. .
.especially the income.
Then and Now
Atwater left no stone unturned in gathering
data on the eating habits of people worldwide. He scoured the European
literature, wrote to missionaries in India, and cited studies of Chinese living
on the U.S. Pacific coast, among others.
But the data he collated would pale beside
the hundreds of intake studies done today, ranging from surveys of small
population subgroups to those of national scope. Unlike the earlier surveys,
today's studies are based on scientific samplings that accurately reflect the
populations under scrutiny.
USDA's Human Nutrition Information Service
(HNIS) and the Department of Health and Human Service's National Center for
Health Statistics are the two federal agencies responsible for conducting the
major national surveys. Happily, the two agencies are located side-by-side in
Hyattsville, Maryland.
ARS, while rarely involved in population
surveys, develops or improves tools used in collecting and analyzing such data.
For example, researchers at the Western Human Nutrition Research Center in San
Francisco have automated the recordkeeping for smaller surveys.
Volunteers need only enter bar codes of the
food they eat and weigh the portions. A laptop computer connected to the scale
computes and stores the data for later evaluation.
Studies done with NESSYthe Nutrition
Evaluation Scale Systemshow it doesn't cause people to eat less than they
normally would. That's been a problem before, when people are asked to write
down everything that passes through their lips.
|
Human nutrition study participants eat meals low in folic acid.
|
All five ARS
centers develop or improve methods to assess people's nutritional status,
particularly by noninvasive means. But it is a major emphasis at the Western
center. Scientists there focus on marginal vitamin and mineral
deficiencieswhich are much more common than severe malnutrition in this
countryand also on the consequences of excess intakes.
More than a decade ago, the Human Nutrition
Research Center on Aging at Tufts in Boston was launched to study the role of
nutrition in keeping people healthy well into old age. One of the first orders
of business was to get a nutritional profile of the over-60 population.
Center scientists gathered data on the diets
and nutritional status of nearly 700 people living on their own in the Boston
area and of some 350 living in nursing homes. The eldest was 102. The survey
provided much data on this rapidly growing segment of the U.S. population and
has served to guide researchers to problem areas or unanswered
questions.
In 1896, Atwater and Wesleyan graduate
student A.P. Bryant published The Chemical Composition of American Food
Materials, or simply, Bulletin No. 28. This bulletin would become the
forerunner of USDA's Agriculture Handbook 8the dietitian's bible. It
listed the minimum, maximum, and average values of the known nutrients in all
American foods analyzed by July 1895.
Within 4 years, so many new analyses
had appeared that a revised edition of the bulletin was issued, wrote
Ross A. Gortner, Jr., who followed Atwater at Wesleyan University. More
than a third of all these analyses were performed by Atwater and his associates
in the chemical laboratory at Wesleyan.
A 1906 reprinting of the bulletin, with only
minor changes, stood until June of 1940 when USDA Circular No. 549 was
published. Gortner noted, I'm sure that [Atwater] could not have
anticipated that it would not be superseded until some 40 years
later....
The responsibility for maintaining and
updating data on the composition of American foods now lies with the HNIS.
Chemists at ARS' Human Nutrition Research Center in Beltsville, Maryland, work
hand in hand with HNIS to develop faster, simpler, or more accurate analytical
methods and to ensure quality control in the testing laboratories.
|
Sweet, juicy strawberries not only taste good, they're also full of nutrition.
Low in calories and carbohydrates, the raw fruit is a good source of fiber
potassium, iron, and vitamin C.
|
For example,
they have streamlined the official analytical methods for assessing dietary
fiber as well as for cholesterol in mixed foods. And they have developed
several food standards that testing laboratories use to check their procedures
for accuracy.
Research is also being conducted on vitamins
and other food constituents that appear to prevent heart disease or cancer,
such as carotenoids and flavonoids. These two classes of compounds are abundant
in many fruits and vegetables and give these foods their distinctive colors and
flavors.
The analytical sensitivity of many of
the methods that are being used could not have been imagined by scientists
during the time of Atwater, says Joseph T. Spence, director of the Beltsville
center.
What Do Fresh Foods Lose?
Atwater also wanted to know how cooking and
processing affected the nutritional quality of foods. He launched studies on
nutrient losses during the boiling of vegetables, digestibility of breakfast
cereals, changes incurred in the cooking of meats, and effects of milling and
baking bread.
Because he was concerned only with fats,
carbohydrates, and proteins, some of Atwater's conclusions are faulty today.
For instance, he found that people absorbed more of these nutrients from bread
when the flour was finely ground. So he concluded that milling wheat to retain
a large proportion of the bran and germ decreased its nutritional value.
Today, we know that whole wheat flour
contains vitamins, minerals, and fiber not found in white flour.
This line of research is now largely in the
hands of state universities, although a good deal is conducted by the food
industry for its own use. ARS, on the other hand, is heavily involved in
breeding crops having better balance and availability of nutrients, such as
beta carotene or beta glucans, and meat animals with less fat or less saturated
fat.
|
Biological aide Ellie Giron (left) and ARS chemist Phyllis Johnson prepare a
sample for analysis at the ARS Grand Forks Human Nutrition Research Center in
Grand Forks, North Dakota.
|
One ARS study,
however, captured the news in 1992. It looked at the effects of trans fatty
acids on blood cholesterol. These fats are formed when vegetable oils are
hydrogenated to make margarine and many other products. The study showed that
they have the potential to raise cholesterol and their place in the diet has
become a matter of controversy. Now Beltsville researchers are working to
define the circumstances under which this might occur.
Just the Right Amount?
Most of the research done by ARS nutrition
centers is about nutrient requirements. Knowledge of the types and amounts of
nutrients we need to consume each day has grown exponentially since the days of
Atwater. All of the vitamins and most of the minerals and trace elements known
to date were discovered after his death in 1907. And other food constituents
are proving their value against cancer, diabetes, or heart disease.
What's more, the emphasis is no longer on
increasing human physical output or preventing deficiency diseases. Research
today aims at enabling everyone to reach their optimum health, given the genes
they are dealt at conception, and to maintain it as long as they live.
The best way to maintain good health
throughout life is to get off to a good start. That's why the Children's
Nutrition Research Center was begun in 1978 as a cooperative venture with
Baylor College of Medicine and Texas Children's Hospital in Houston.
Most of the studies have dealt with infants,
including the tiniest preemies, pregnant women, and nursing mothers. But
research here is expanding to address energy and other nutrient requirements of
children and the special needs of pregnant and nursing teenagers.
Houston researchers are finding that the
proteins and fats in mother's milk do more than nourish the infant. Some of
them signal the infant's immune and digestive systems to mature, as well as
affect the infant's overall health.
This could explain why breast-fed infants
took in one-fourth fewer calories and one-half less protein than formula-fed
infants, yet gained and developed with greater efficiency, says center director
Buford Nichols. He believes that the search for these and other
'molecular messages in the diet of infants and adults will continue to dominate
nutrition research into the next century.
|
Thanks to research, carrots, onions, garlic and cucumbers taste better and
contain more nutrients.
|
A substantial
amount of the center's work goes into developing safe and noninvasive studies
that can be done on infants, even those born before term. Researchers have
perfected the use of stable isotopesthose nonradioactive variants of
nature's elements. They can determine which amino acids an infant is
synthesizing at a given time or how fast it is making its own cholesterol.
These data will help nutritionists establish optimum diets for infants.
At the Western center, scientists are
learning how adults can get a proper balance of nutrients when faced with the
vast selection of foods in the marketplaceespecially when health
organizations and the federal government are recommending major changes in our
diets. With only slight changes in food items, researchers were able to select
diets containing 25 to 30 percent of calories from fat, much less cholesterol,
and a higher ratio of polyunsaturated to saturated fat than in average
contemporary diets.
The diets not only reduced serum
cholesterol, says acting center director Judith R. Turnlund, they also had a
dramatically higher vitamin and mineral content because of extra
carbohydrates.
Studies at the Grand Forks [North Dakota]
Human Nutrition Research Center over the past 20 years have resulted in the
discovery of new trace elementssuch as boronas wel1 as new
functions for known ones. That's the main mission of the Grand Forks center,
although the Western and Beltsville centers are also involved in trace element
research.
But discovery is just the beginning.
Researchers need to determine how much is essential, what foods supply the
element, what factors interfere with or enhance the body's absorption or use of
it, and more. What's more, they also study established trace elements that are
consumed in only thousandths or millionths of a gram, to learn the consequences
of marginal intakes.
For example, in studies at Grand Forks,
boron is proving to play a role in maintaining healthy bones and optimal brain
and motor function. And adequate intakes of two well-known trace
elementsiron and zinchave been found necessary for people to
maintain body temperature in the cold, in addition to their established
functions. [See Agricultural Research, October 1992, pp. 4-11.]
Researchers at all five centers are
developing or improving methods for measuring body fat and lean tissue. Many
Americans are overfed: A high fat-to-lean ratio is our biggest health hazard.
It's especially serious in the elderly, because they lose lean tissue at a much
faster rate than younger people.
|
|
The Boston
center, established in 1980, operates under a contract between ARS and Tufts
University. Researchers there are breaking new ground in learning the special
needs of older people.
Recommended Dietary Allowances have been
estimated largely from studies of younger adults because of the paucity of data
on the aging population. In fact, the RDA's currently put all people over 50
into a single category. But an 80-year-old is no more like a 50-year old than
the latter is like a 20-year-old.
Center studies have shown that the loss of
acid-secreting cells in the stomacha common problem with agingcan
interfere with absorption of vitamin B-12 from food but not from supplements.
It also appears that senior citizens need to consume more vitamin B6 than
currently recommended for their age group. And women past menopause need more
vitamin D, as well as adequate calcium, to prevent osteoporosis.
A good deal of research at the Boston center
deals with antioxidants, such as vitamins C and E and beta carotene. If the
process of aging that we once took for granted is due to cumulative damage by
oxygen free radicals, then increasing antioxidants may help prevent it, theory
holds. And studies suggest that antioxidant vitamins may delay cataracts or
boost a flagging immune system.
The most promising news out of the center
shows that declines in cardiovascular fitness and muscle strength are due to
inactivity rather than aging. Elderly people can vastly improve both functions
with the right exercises. There truly is no age limit on getting fit.
Atwater recognized his limited knowledge
when he wrote in the 1894 USDA Yearbook of Agriculture: Some foods have
at times a great value outside of their use for nourishment. Fruits and garden
vegetables often benefit people greatly not as mere nutriment.... His
words were prophetic: These foods provide a wealth of vitamins, minerals, and
compounds like carotenoids; they also provide a lot of fiber.
And the concept of nutriment continues to
grow.
Who knows how many food
constituentsunknown or ignoredfuture research will show to have
unsuspected effects on our metabolic processes? That's why it is so important
to get our nutrients from a variety of fresh foods instead of relying on
vitamin supplements to substitute for a poor diet. Look what we might be
missing.By Judy McBride, ARS, with contributions from nutrition
research center directors Buford Nichols, Forrest Nielsen, Joseph
Spence, and Judith Turnlund.
|
This article appeared as "W.O. Atwater - Father of
American Nutrition Science", published in the June 1993 issue of Agricultural Research magazine.
Send comments or questions about this historical timeline to
Sean Adams.
|
|
|
|