Introduction
More than a decade and a half ago, the U.S. Department of Agriculture
(USDA) created a powerful and enduring icon: the Food Guide Pyramid.
This simple illustration conveyed in a flash what the USDA said were the
elements of a healthy diet. The Pyramid was taught in schools, appeared
in countless media articles and brochures, and was plastered on cereal
boxes and food labels.
Tragically, the information embodied in this pyramid didn’t point the
way to healthy eating. Why not? Its blueprint was based on shaky
scientific evidence, and it barely changed over the years to reflect
major advances in our understanding of the connection between diet and
health.
With much fanfare, in 2005, the USDA retired the old Food Guide
Pyramid and replaced it with MyPyramid, a new symbol and “interactive
food guidance system.” The new symbol is basically the old Pyramid
turned on its side.
The good news is that this dismantles and buries the flawed Pyramid.
The bad news is that the new symbol doesn’t convey enough information to
help you make informed choices about your diet and long-term health.
And it continues to recommend foods that aren’t essential to good
health, and may even be detrimental in the quantities included in
MyPyramid.
As an alternative to the USDA’s flawed pyramid, faculty members at
the Harvard School of Public Health built the Healthy Eating Pyramid. It
resembles the USDA’s in shape only. The Healthy Eating Pyramid takes
into consideration, and puts into perspective, the wealth of research
conducted during the last 15 years that has reshaped the definition of
healthy eating.
Pyramid Building
In the children’s book
Who Built the Pyramid?,
(
1)
different people take credit for building the once-grand pyramid of
Senwosret. King Senwosret, of course, claims the honor. But so does his
architect, the quarry master, the stonecutters, slaves, and the boys who
carried water to the workers.
The USDA’s MyPyramid also had many builders. Some are obvious—USDA
scientists, nutrition experts, staff members, and consultants. Others
aren’t. Intense lobbying efforts from a variety of food industries also
helped shape the pyramid.
In theory, the USDA pyramid should reflect the nutrition advice assembled in the
Dietary Guidelines for Americans.
According to the USDA, the guidelines “provide authoritative advice for
people two years and older about how good dietary habits can promote
health and reduce risk for major chronic diseases.”
This document, which by law must be revised every five years, aims to
offer sound nutrition advice that corresponds to the latest scientific
research. The panel assembled to create the guidelines usually generates
100 or so pages of dense nutrition-speak. This document is translated
into a reader friendly
brochure
aimed at helping the average person choose a balanced and healthy diet.
Of far greater importance, the Dietary Guidelines for Americans set the
standards for all federal nutrition programs, including the school
lunch program, and helps determine what food products Americans buy. In
other words, the guidelines influence how billions of dollars are spent
each year. So even minor changes can hurt or help a food industry.
According to federal regulations, the panel that writes the dietary
guidelines must include nutrition experts who are leaders in pediatrics,
obesity, cardiovascular disease, and public health. Selecting the
panelists is no easy task, and is subject to intense lobbying from
organizations such as the National Dairy Council, United Fresh Fruit and
Vegetable Association, Soft Drink Association, American Meat Institute,
National Cattlemen’s Beef Association, and Wheat Foods Council. (
2)
Dietary Guidelines 2005: Two Steps Forward, One Step Back
Released in early January 2005, the Dietary Guidelines for Americans
2005 continues to reflect the tense interplay of science and the
powerful food industry. Several of the recommendations in the current
version represent important steps in the right direction:
- The current guidelines emphasize the importance of controlling
weight, which was not adequately addressed in previous versions. And
they continue to stress the importance of physical activity.
- The recommendation on dietary fats makes a clear break from the
past, when all fats were considered bad. The guidelines now emphasize
that intake of trans fats should be as low as possible and that
saturated fat should be limited. There is no longer an artificially low
cap on fat intake. The latest advice recommends getting between 20 and
35 percent of daily calories from fats and recognizes the potential
health benefits of monounsaturated and polyunsaturated fats.
- Instead of emphasizing “complex carbohydrates,” a term used in the
past that has little biological meaning, the new guidelines urge
Americans to limit sugar intake and they stress the benefits of whole
grains.
Others remain mired in the past:
- The guidelines suggest that it is fine to consume half of our grains
as refined starch. That’s a shame, since refined starches, such as
white bread and white rice, behave like sugar. They add empty calories,
have adverse metabolic effects, and increase the risks of diabetes and
heart disease.
- In terms of protein, the guidelines continue to lump together red
meat, poultry, fish, and beans (including soy products). They ask us to
judge these protein sources by their total fat content, and “make
choices that are lean, low-fat, or fat-free.” This ignores the evidence
that these foods have different types of fats. It also overlooks
mounting evidence that replacing red meat with a combination of fish,
poultry, beans, and nuts offers numerous health benefits.
- The recommendation to drink three glasses of low-fat milk or eat
three servings of other dairy products per day to prevent osteoporosis
is another step in the wrong direction. Of all the recommendations, this
one represents the most radical change from current dietary patterns.
Three glasses of low-fat milk a day amounts to more than 300 extra
calories a day. This is a real issue for the millions of Americans who
are trying to control their weight. What’s more, millions of Americans
are lactose intolerant, and even small amounts of milk or dairy products
give them stomachaches, gas, or other problems. This recommendation
ignores the lack of evidence for a link between consumption of dairy
products and prevention of osteoporosis. It also ignores the possible
increases in risk of ovarian cancer and prostate cancer associated with
dairy products.
Dietary Guidelines 2010: Progress, Not Perfection
The long-awaited new U.S. dietary guidelines, released on January 31,
2011, are a step in the right direction, but they don’t go quite far
enough to spell out what Americans need to do to stay healthy—not a
surprise, given the strong influence of the food industry on U.S. food
policy.
Read more about the new Dietary Guidelines for Americans 2010.
The USDA Pyramid, Brick by Brick
Distilling nutrition advice into a pyramid was a stroke of genius.
The shape immediately suggests that some foods are good and should be
eaten often, and that others aren’t so good and should be eaten only
occasionally. The layers represent major food groups that contribute to
the total diet. MyPyramid tries to do this in an abstract way, and
fails.
Six swaths of color sweep from the apex of MyPyramid to the base:
orange for grains, green for vegetables, red for fruits, a teeny band of
yellow for oils, blue for milk, and purple for meat and beans. Each
stripe starts out as the same size, but they don’t end that way at the
base. The widths suggest how much food a person should choose from each
group. A band of stairs running up the side of the Pyramid, with a
little stick figure chugging up it, serves as a reminder of the
importance of physical activity.
MyPyramid contains no text. According to the USDA, it was “designed
to be simple,” and details are at MyPyramid.gov. Unless you’ve taken the
time to become familiar with the Pyramid, though, you have no idea what
it means. Relying on the Web site to provide key information—like what
the color stripes stand for and what the best choices are in each food
group—guarantees that the millions of Americans without access to a
computer or the Internet will have trouble getting these essential
facts.
The USDA also chose not to put recommended numbers of servings on the
new Pyramid because these differ from individual to individual
according to weight, gender, activity level and age. Instead, it offers
personalized Pyramids at
MyPyramid.gov.
Building a Better Pyramid
If the only goal of MyPyramid is to give us the best possible advice
for healthy eating, then it should be grounded in the evidence and be
independent of business.
Instead of waiting for this to happen, nutrition experts from the
Harvard School of Public Health created the Healthy Eating Pyramid, and
updated it in 2008. The Healthy Eating Pyramid is based on the best
available scientific evidence about the links between diet and health.
This new pyramid fixes fundamental flaws in the USDA pyramid and offers
sound information to help people make better choices about what to eat.
(View a larger PDF image of the new pyramid, in a separate window.)
The Healthy Eating Pyramid sits on a foundation of daily exercise and
weight control. Why? These two related elements strongly influence your
chances of staying healthy. They also affect what you eat and how your
food affects you.
Exercise and weight control are also linked through the simple rule
of energy balance: Weight change = calories in – calories out. If you
burn as many calories as you take in each day, there’s nothing left over
for storage in fat cells, and weight remains the same. Eat more than
you burn, though, and you end up adding fat and pounds. Regular exercise
can help you control your weight, and it is key part of any weight-loss
effort.
The other bricks of the Healthy Eating Pyramid include the following:
Whole Grains
The body needs carbohydrates mainly for energy. The best sources of
carbohydrates are whole grains such as oatmeal, whole wheat bread, and
brown rice. They deliver the outer (bran) and inner (germ) layers along
with energy-rich starch. The body can’t digest whole grains as quickly
as it can highly processed carbohydrates such as white flour. This keeps
blood sugar and insulin levels from rising, then falling, too quickly.
Better control of blood sugar and insulin can keep hunger at bay and may
prevent the development of type 2 diabetes. Plus, a growing body of
research suggests that eating a diet rich in whole grains may also
protect against heart disease.
Healthy Fats and Oils
Surprised that the Healthy Eating Pyramid puts some fats near the base,
indicating they are okay to eat? Although this recommendation seems to
go against conventional wisdom, it’s exactly in line with the evidence
and with common eating habits. The average American gets one-third or
more of his or her daily calories from fats, so placing them near the
foundation of the pyramid makes sense. Note, though, that it
specifically mentions healthy fats and oils, not all types of fat. Good
sources of healthy unsaturated fats include olive, canola, soy, corn,
sunflower, peanut, and other vegetable oils, trans fat-free margarines,
nuts, seeds, avocados, and fatty fish such as salmon. These healthy fats
not only improve cholesterol levels (when eaten in place of highly
processed carbohydrates) but can also protect the heart from sudden and
potentially deadly rhythm problems.
Vegetables and Fruits
A
diet rich in vegetables and fruits has bountiful benefits. Among them:
It can decrease the chances of having a heart attack or stroke; possibly
protect against some types of cancers; lower blood pressure; help you
avoid the painful intestinal ailment called diverticulitis; guard
against cataract and macular degeneration, the major causes of vision
loss among people over age 65; and add variety to your diet and wake up
your palate.
Nuts, Seeds, Beans, and Tofu
These plant foods are excellent sources of protein, fiber, vitamins,
and minerals. Beans include black beans, navy beans, garbanzos, lentils,
and other beans that are usually sold dried. Many kinds of nuts contain
healthy fats, and packages of some varieties (almonds, walnuts, pecans,
peanuts, hazelnuts, and pistachios) can now even carry a label saying
they’re good for your heart.
Fish, Poultry, and Eggs
These foods are also important sources of protein. A wealth of research
suggests that eating fish can reduce the risk of heart disease, since
fish is rich in heart-healthy omega-3 fats. Chicken and turkey are also
good sources of protein and can be low in saturated fat. Eggs, which
have long been demonized because they contain fairly high levels of
cholesterol, aren’t as bad as they’ve been cracked up to be. In fact, an
egg is a much better breakfast than a doughnut cooked in an oil rich in
trans fats or a bagel made from refined flour. People with diabetes or
heart disease, however, should limit their egg yolk consumption to no
more than 3 a week. But egg whites are very high in protein and are a
fine substitute for whole eggs in omelets and baking.
Dairy (1 to 2 Servings Per Day) or Vitamin D/Calcium Supplements
Building bone and keeping it strong takes calcium, vitamin D, exercise,
and a whole lot more. Dairy products have traditionally been Americans’
main source of calcium and, through fortification, vitamin D. But most
people need at least 1,000 IU of vitamin D per day, far more than the
100 IU supplied by a glass of fortified milk. (See the multivitamins
section, below, for more information on vitamin D needs.) And there are
other healthier ways to get calcium than from milk and cheese, which can
contain a lot of saturated fat. Three glasses of whole milk, for
example, contains as much saturated fat as 13 strips of cooked bacon. If
you enjoy dairy foods, try to stick mainly with no-fat or low-fat
products. If you don’t like dairy products, taking a vitamin D and
calcium supplement offers an easy and inexpensive way to meet your daily
vitamin D and calcium needs.
Use Sparingly: Red Meat, Processed Meat, and Butter
These sit at the top of the Healthy Eating Pyramid because they
contain lots of saturated fat. Processed meats, such as bacon, hot dogs,
and deli meats are also very high in added sodium. Eating a lot of red
meat and processed meat has been linked to increased risk of heart
disease, diabetes, and colon cancer. If you eat red meat every day,
switching to fish, chicken, or beans several times a week can improve
cholesterol levels. So can switching from butter to olive oil. And
eating fish has other benefits for the heart.
Use Sparingly: Refined Grains—White Bread, Rice, and Pasta; Potatoes; Sugary Drinks and Sweets; Salt
Why are these all-American staples at the top, rather than the
bottom, of the Healthy Eating Pyramid? White bread, white rice, white
pasta, other refined grains, potatoes,
sugary drinks,
and sweets can cause fast and furious increases in blood sugar that can
lead to weight gain, diabetes, heart disease, and other chronic
disorders. Whole grain carbohydrates cause slower, steadier increases in
blood sugar that don’t overwhelm the body’s ability to handle
carbohydrate. The
salt shaker
is a new addition to the “Use Sparingly” tip of the Healthy Eating
Pyramid, one that’s based on extensive research linking high-sodium
diets to increased risk of heart attack and stroke. (Read more about
why cutting back on salt is good for your health, and try these
delicious recipes from The Culinary Institute of America that spare the salt.)
Multivitamin with Extra Vitamin D (For Most People)
A daily multivitamin, multimineral supplement offers a kind of
nutritional backup, especially when it includes some extra vitamin D.
While a multivitamin can’t in any way replace healthy eating, or make up
for unhealthy eating, it can fill in the nutrient holes that may
sometimes affect even the most careful eaters. You don’t need an
expensive name-brand or designer vitamin. A standard, store-brand,
RDA-level one is fine for most nutrients—except vitamin D. In addition
to its bone-health benefits, there’s growing evidence that getting some
extra vitamin D can help lower the risk of colon and breast cancer. Aim
for getting at least 1,000 IU of vitamin D per day; multiple vitamins
are now available with this amount. (Many people, especially those who
spend the winter in the northern U.S. or have darker skin, will need
extra vitamin D, often a total of 3,000 to 4,000 IU per day, to bring
their blood levels up to an adequate range. If you are unsure, ask your
physician to check your blood level.) Look for a multivitamin that meets
the requirements of the USP (U.S. Pharmacopeia), an organization that
sets standards for drugs and supplements.
Optional: Alcohol in Moderation (Not for Everyone)
Scores of studies suggest that having an alcoholic drink a day lowers
the risk of heart disease. Moderation is clearly important, since
alcohol has risks as well as benefits. For men, a good balance point is
one to two drinks a day; in general, however, the risks of drinking,
even in moderation, exceed benefits until middle age. For women, it’s at
most one drink a day; women should avoid alcohol during pregnancy.
Forget about Numbers and Focus on Quality
You’ll notice that the Healthy Eating Pyramid does not give specific
advice about the numbers of cups or ounces to have each day of specific
foods. That’s because it’s not meant to be a rigid road map, and the
amounts can vary depending on your body size and physical activity. It’s
a simple, general, flexible guide to how you should eat when you eat.
There’s just one basic guideline to remember: A healthy diet includes
more foods from the base of the pyramid than from the higher levels of
the pyramid. Within this guideline, however, there’s plenty of
flexibility for different styles of eating and different food choices. A
vegetarian can follow the Healthy Eating Pyramid by emphasizing nuts,
beans, and other plant sources of protein, and choosing non-dairy
sources of calcium and vitamin D; someone who eats animal products can
choose fish or chicken for protein, with occasional red meat.
Choosing a variety of fresh, whole foods from all the food groups
below the “Use Sparingly” category in the Healthy Eating Pyramid will
ensure that you get the nutrients you need. It will also dramatically
lower your salt intake, since most of the salt in the U.S. diet lurks in
processed food—canned soups, frozen dinners, deli meats, snack chips,
and the like.
Perhaps the only foods that are truly off-limits are foods that
contain trans fat from partially hydrogenated oils. Luckily, in the U.S.
and Canada, trans fats must be listed on nutrition labels. More and
more food manufacturers, restaurants, and even entire communities are
going trans fat-free, making it easier to avoid this health-damaging
type of fat.
Other Alternatives
The Healthy Eating Pyramid summarizes the best dietary information
available today. It isn’t set in stone, though, because nutrition
researchers will undoubtedly turn up new information in the years ahead.
The Healthy Eating Pyramid will change to reflect important new
evidence.
This isn’t the only alternative to the USDA’s MyPyramid. The Asian, Latin, Mediterranean, and vegetarian pyramids promoted by
Oldways Preservation and Exchange Trust
are also good, evidence-based guides for healthy eating. The Healthy
Eating Pyramid takes advantage of even more extensive research and
offers a broader guide that is not based on a specific culture. The
original Healthy Eating Pyramid is described in greater detail in
Eat, Drink, and Be Healthy: The Harvard Medical School Guide to Healthy Eating,
by Walter C. Willett, M.D. (the Fredrick John Stare Professor of
Epidemiology and Nutrition in the Departments of Nutrition and
Epidemiology at Harvard School of Public Health) with Patrick J.
Skerrett (published by Free Press, 2005).
Failing the Test
Back in the 1990s, the USDA’s Center for Nutrition Policy and
Promotion created the Healthy Eating Index “to measure how well American
diets conform to recommended healthy eating patterns.” (
3)
In its original form, this score sheet used five elements from the
longstanding USDA Food Guide Pyramid (number of daily servings of
grains, vegetables, fruits, meat, and dairy products) and five from the
1995 Dietary Guidelines for Americans (total fat in the diet, percentage
of calories from saturated fat, cholesterol intake, sodium intake, and
variety of the diet). A score of 100 meant following the federal
recommendations to the letter while a score of 0 meant totally ignoring
them. (The USDA has since
updated the score sheet to reflect the Dietary Guidelines for Americans 2005.)
To see how well the principles embodied in the Healthy Eating Pyramid
stacked up against the government’s advice, Harvard School of Public
Health researchers created an Alternate Healthy Eating Index with a
scoring system similar to the USDA’s index. They then compared the two
indexes, using information about daily diets collected from more than
100,000 female nurses and male health professionals taking part in two
long-term studies.
Men who scored highest on the USDA’s original Healthy Eating Index
(meaning their diets most closely followed federal recommendations)
reduced their overall risk of developing heart disease, cancer, or other
chronic disease by 11 percent over 8 to 12 years of follow-up compared
to those who scored lowest. Women who most closely followed the
government’s recommendations were only 3 percent less likely to have
developed a chronic disease. (
4)
In comparison, scores on the Alternate Healthy Eating Index did appear
to correlate more closely with disease in both sexes. Men with high
scores (those whose diets most closely followed the Healthy Eating
Pyramid guidelines) were 20 percent less likely to have developed a
major chronic disease than those with low scores. Women with high scores
lowered their overall risk by 11 percent. Men whose diets most closely
followed the Healthy Eating Pyramid lowered their risk of cardiovascular
disease by almost 40 percent; women with high scores lowered their risk
by almost 30 percent.
Table of Contents
Introduction
More than a decade and a half ago, the U.S. Department of Agriculture
(USDA) created a powerful and enduring icon: the Food Guide Pyramid.
This simple illustration conveyed in a flash what the USDA said were the
elements of a healthy diet. The Pyramid was taught in schools, appeared
in countless media articles and brochures, and was plastered on cereal
boxes and food labels.
Tragically, the information embodied in this pyramid didn’t point the
way to healthy eating. Why not? Its blueprint was based on shaky
scientific evidence, and it barely changed over the years to reflect
major advances in our understanding of the connection between diet and
health.
With much fanfare, in 2005, the USDA retired the old Food Guide
Pyramid and replaced it with MyPyramid, a new symbol and “interactive
food guidance system.” The new symbol is basically the old Pyramid
turned on its side.
The good news is that this dismantles and buries the flawed Pyramid.
The bad news is that the new symbol doesn’t convey enough information to
help you make informed choices about your diet and long-term health.
And it continues to recommend foods that aren’t essential to good
health, and may even be detrimental in the quantities included in
MyPyramid.
As an alternative to the USDA’s flawed pyramid, faculty members at
the Harvard School of Public Health built the Healthy Eating Pyramid. It
resembles the USDA’s in shape only. The Healthy Eating Pyramid takes
into consideration, and puts into perspective, the wealth of research
conducted during the last 15 years that has reshaped the definition of
healthy eating.
Pyramid Building
In the children’s book
Who Built the Pyramid?,
(
1)
different people take credit for building the once-grand pyramid of
Senwosret. King Senwosret, of course, claims the honor. But so does his
architect, the quarry master, the stonecutters, slaves, and the boys who
carried water to the workers.
The USDA’s MyPyramid also had many builders. Some are obvious—USDA
scientists, nutrition experts, staff members, and consultants. Others
aren’t. Intense lobbying efforts from a variety of food industries also
helped shape the pyramid.
In theory, the USDA pyramid should reflect the nutrition advice assembled in the
Dietary Guidelines for Americans.
According to the USDA, the guidelines “provide authoritative advice for
people two years and older about how good dietary habits can promote
health and reduce risk for major chronic diseases.”
This document, which by law must be revised every five years, aims to
offer sound nutrition advice that corresponds to the latest scientific
research. The panel assembled to create the guidelines usually generates
100 or so pages of dense nutrition-speak. This document is translated
into a reader friendly
brochure
aimed at helping the average person choose a balanced and healthy diet.
Of far greater importance, the Dietary Guidelines for Americans set the
standards for all federal nutrition programs, including the school
lunch program, and helps determine what food products Americans buy. In
other words, the guidelines influence how billions of dollars are spent
each year. So even minor changes can hurt or help a food industry.
According to federal regulations, the panel that writes the dietary
guidelines must include nutrition experts who are leaders in pediatrics,
obesity, cardiovascular disease, and public health. Selecting the
panelists is no easy task, and is subject to intense lobbying from
organizations such as the National Dairy Council, United Fresh Fruit and
Vegetable Association, Soft Drink Association, American Meat Institute,
National Cattlemen’s Beef Association, and Wheat Foods Council. (
2)
Dietary Guidelines 2005: Two Steps Forward, One Step Back
Released in early January 2005, the Dietary Guidelines for Americans
2005 continues to reflect the tense interplay of science and the
powerful food industry. Several of the recommendations in the current
version represent important steps in the right direction:
- The current guidelines emphasize the importance of controlling
weight, which was not adequately addressed in previous versions. And
they continue to stress the importance of physical activity.
- The recommendation on dietary fats makes a clear break from the
past, when all fats were considered bad. The guidelines now emphasize
that intake of trans fats should be as low as possible and that
saturated fat should be limited. There is no longer an artificially low
cap on fat intake. The latest advice recommends getting between 20 and
35 percent of daily calories from fats and recognizes the potential
health benefits of monounsaturated and polyunsaturated fats.
- Instead of emphasizing “complex carbohydrates,” a term used in the
past that has little biological meaning, the new guidelines urge
Americans to limit sugar intake and they stress the benefits of whole
grains.
Others remain mired in the past:
- The guidelines suggest that it is fine to consume half of our grains
as refined starch. That’s a shame, since refined starches, such as
white bread and white rice, behave like sugar. They add empty calories,
have adverse metabolic effects, and increase the risks of diabetes and
heart disease.
- In terms of protein, the guidelines continue to lump together red
meat, poultry, fish, and beans (including soy products). They ask us to
judge these protein sources by their total fat content, and “make
choices that are lean, low-fat, or fat-free.” This ignores the evidence
that these foods have different types of fats. It also overlooks
mounting evidence that replacing red meat with a combination of fish,
poultry, beans, and nuts offers numerous health benefits.
- The recommendation to drink three glasses of low-fat milk or eat
three servings of other dairy products per day to prevent osteoporosis
is another step in the wrong direction. Of all the recommendations, this
one represents the most radical change from current dietary patterns.
Three glasses of low-fat milk a day amounts to more than 300 extra
calories a day. This is a real issue for the millions of Americans who
are trying to control their weight. What’s more, millions of Americans
are lactose intolerant, and even small amounts of milk or dairy products
give them stomachaches, gas, or other problems. This recommendation
ignores the lack of evidence for a link between consumption of dairy
products and prevention of osteoporosis. It also ignores the possible
increases in risk of ovarian cancer and prostate cancer associated with
dairy products.
Dietary Guidelines 2010: Stay Tuned
What is on the horizon for the next version of the Dietary Guidelines
for Americans, due out before the end of 2010? The scientific advisory
committee for the 2010 guidelines released its
report
on June 15, 2010. The committee recommended that the next iteration of
the guidelines call for reducing overall calorie intake across the U.S.
population and increasing physical activity to reduce the number of
Americans who are overweight or obese; shifting to a more plant-based
diet; and reducing the intake of foods containing added sugars and solid
fats (which deliver calories but few nutrients), excess salt, and
highly refined grains. It remains to be seen how these recommendations
will be distilled into the final guidelines.
Read more about the making of the 2010 Dietary Guidelines Advisory Committee report.
Read a commentary from Dr. Walter Willett (PDF) and colleagues on the 2010 Dietary Guidelines Advisory Committee report.
The USDA Pyramid, Brick by Brick
Distilling nutrition advice into a pyramid was a stroke of genius.
The shape immediately suggests that some foods are good and should be
eaten often, and that others aren’t so good and should be eaten only
occasionally. The layers represent major food groups that contribute to
the total diet. MyPyramid tries to do this in an abstract way, and
fails.
Six swaths of color sweep from the apex of MyPyramid to the base:
orange for grains, green for vegetables, red for fruits, a teeny band of
yellow for oils, blue for milk, and purple for meat and beans. Each
stripe starts out as the same size, but they don’t end that way at the
base. The widths suggest how much food a person should choose from each
group. A band of stairs running up the side of the Pyramid, with a
little stick figure chugging up it, serves as a reminder of the
importance of physical activity.
MyPyramid contains no text. According to the USDA, it was “designed
to be simple,” and details are at MyPyramid.gov. Unless you’ve taken the
time to become familiar with the Pyramid, though, you have no idea what
it means. Relying on the Web site to provide key information—like what
the color stripes stand for and what the best choices are in each food
group—guarantees that the millions of Americans without access to a
computer or the Internet will have trouble getting these essential
facts.
The USDA also chose not to put recommended numbers of servings on the
new Pyramid because these differ from individual to individual
according to weight, gender, activity level and age. Instead, it offers
personalized Pyramids at
MyPyramid.gov.
Building a Better Pyramid
If the only goal of MyPyramid is to give us the best possible advice
for healthy eating, then it should be grounded in the evidence and be
independent of business.
Instead of waiting for this to happen, nutrition experts from the
Harvard School of Public Health created the Healthy Eating Pyramid, and
updated it in 2008. The Healthy Eating Pyramid is based on the best
available scientific evidence about the links between diet and health.
This new pyramid fixes fundamental flaws in the USDA pyramid and offers
sound information to help people make better choices about what to eat.
(View a larger PDF image of the new pyramid, in a separate window.)
The Healthy Eating Pyramid sits on a foundation of daily exercise and
weight control. Why? These two related elements strongly influence your
chances of staying healthy. They also affect what you eat and how your
food affects you.
Exercise and weight control are also linked through the simple rule
of energy balance: Weight change = calories in – calories out. If you
burn as many calories as you take in each day, there’s nothing left over
for storage in fat cells, and weight remains the same. Eat more than
you burn, though, and you end up adding fat and pounds. Regular exercise
can help you control your weight, and it is key part of any weight-loss
effort.
The other bricks of the Healthy Eating Pyramid include the following:
Whole Grains
The body needs carbohydrates mainly for energy. The best sources of
carbohydrates are whole grains such as oatmeal, whole wheat bread, and
brown rice. They deliver the outer (bran) and inner (germ) layers along
with energy-rich starch. The body can’t digest whole grains as quickly
as it can highly processed carbohydrates such as white flour. This keeps
blood sugar and insulin levels from rising, then falling, too quickly.
Better control of blood sugar and insulin can keep hunger at bay and may
prevent the development of type 2 diabetes. Plus, a growing body of
research suggests that eating a diet rich in whole grains may also
protect against heart disease.
Healthy Fats and Oils
Surprised that the Healthy Eating Pyramid puts some fats near the base,
indicating they are okay to eat? Although this recommendation seems to
go against conventional wisdom, it’s exactly in line with the evidence
and with common eating habits. The average American gets one-third or
more of his or her daily calories from fats, so placing them near the
foundation of the pyramid makes sense. Note, though, that it
specifically mentions healthy fats and oils, not all types of fat. Good
sources of healthy unsaturated fats include olive, canola, soy, corn,
sunflower, peanut, and other vegetable oils, trans fat-free margarines,
nuts, seeds, avocados, and fatty fish such as salmon. These healthy fats
not only improve cholesterol levels (when eaten in place of highly
processed carbohydrates) but can also protect the heart from sudden and
potentially deadly rhythm problems.
Vegetables and Fruits
A
diet rich in vegetables and fruits has bountiful benefits. Among them:
It can decrease the chances of having a heart attack or stroke; possibly
protect against some types of cancers; lower blood pressure; help you
avoid the painful intestinal ailment called diverticulitis; guard
against cataract and macular degeneration, the major causes of vision
loss among people over age 65; and add variety to your diet and wake up
your palate.
Nuts, Seeds, Beans, and Tofu
These plant foods are excellent sources of protein, fiber, vitamins,
and minerals. Beans include black beans, navy beans, garbanzos, lentils,
and other beans that are usually sold dried. Many kinds of nuts contain
healthy fats, and packages of some varieties (almonds, walnuts, pecans,
peanuts, hazelnuts, and pistachios) can now even carry a label saying
they’re good for your heart.
Fish, Poultry, and Eggs
These foods are also important sources of protein. A wealth of research
suggests that eating fish can reduce the risk of heart disease, since
fish is rich in heart-healthy omega-3 fats. Chicken and turkey are also
good sources of protein and can be low in saturated fat. Eggs, which
have long been demonized because they contain fairly high levels of
cholesterol, aren’t as bad as they’ve been cracked up to be. In fact, an
egg is a much better breakfast than a doughnut cooked in an oil rich in
trans fats or a bagel made from refined flour. People with diabetes or
heart disease, however, should limit their egg yolk consumption to no
more than 3 a week. But egg whites are very high in protein and are a
fine substitute for whole eggs in omelets and baking.
Dairy (1 to 2 Servings Per Day) or Vitamin D/Calcium Supplements
Building bone and keeping it strong takes calcium, vitamin D, exercise,
and a whole lot more. Dairy products have traditionally been Americans’
main source of calcium and, through fortification, vitamin D. But most
people need at least 1,000 IU of vitamin D per day, far more than the
100 IU supplied by a glass of fortified milk. (See the multivitamins
section, below, for more information on vitamin D needs.) And there are
other healthier ways to get calcium than from milk and cheese, which can
contain a lot of saturated fat. Three glasses of whole milk, for
example, contains as much saturated fat as 13 strips of cooked bacon. If
you enjoy dairy foods, try to stick mainly with no-fat or low-fat
products. If you don’t like dairy products, taking a vitamin D and
calcium supplement offers an easy and inexpensive way to meet your daily
vitamin D and calcium needs.
Use Sparingly: Red Meat and Butter
These sit at the top of the Healthy Eating Pyramid because they
contain lots of saturated fat. Eating a lot of red meat may also
increase your risk of colon cancer. If you eat red meat every day,
switching to fish , chicken, or beans several times a week can improve
cholesterol levels. So can switching from butter to olive oil. And
eating fish has other benefits for the heart.
Use Sparingly: Refined Grains—White Bread, Rice, and Pasta; Potatoes; Sugary Drinks and Sweets; Salt
Why are these all-American staples at the top, rather than the
bottom, of the Healthy Eating Pyramid? White bread, white rice, white
pasta, other refined grains, potatoes,
sugary drinks,
and sweets can cause fast and furious increases in blood sugar that can
lead to weight gain, diabetes, heart disease, and other chronic
disorders. Whole grain carbohydrates cause slower, steadier increases in
blood sugar that don’t overwhelm the body’s ability to handle
carbohydrate. The
salt shaker
is a new addition to the “Use Sparingly” tip of the Healthy Eating
Pyramid, one that’s based on extensive research linking high-sodium
diets to increased risk of heart attack and stroke. (Read more about
why cutting back on salt is good for your health, and try these
delicious recipes from The Culinary Institute of America that spare the salt.)
Multivitamin with Extra Vitamin D (For Most People)
A daily multivitamin, multimineral supplement offers a kind of
nutritional backup, especially when it includes some extra vitamin D.
While a multivitamin can’t in any way replace healthy eating, or make up
for unhealthy eating, it can fill in the nutrient holes that may
sometimes affect even the most careful eaters. You don’t need an
expensive name-brand or designer vitamin. A standard, store-brand,
RDA-level one is fine for most nutrients—except vitamin D. In addition
to its bone-health benefits, there’s growing evidence that getting some
extra vitamin D can help lower the risk of colon and breast cancer. Aim
for getting at least 1,000 IU of vitamin D per day; multiple vitamins
are now available with this amount. (Many people, especially those who
spend the winter in the northern U.S. or have darker skin, will need
extra vitamin D, often a total of 3,000 to 4,000 IU per day, to bring
their blood levels up to an adequate range. If you are unsure, ask your
physician to check your blood level.) Look for a multivitamin that meets
the requirements of the USP (U.S. Pharmacopeia), an organization that
sets standards for drugs and supplements.
Optional: Alcohol in Moderation (Not for Everyone)
Scores of studies suggest that having an alcoholic drink a day lowers
the risk of heart disease. Moderation is clearly important, since
alcohol has risks as well as benefits. For men, a good balance point is
one to two drinks a day; in general, however, the risks of drinking,
even in moderation, exceed benefits until middle age. For women, it’s at
most one drink a day; women should avoid alcohol during pregnancy.
Forget about Numbers and Focus on Quality
You’ll notice that the Healthy Eating Pyramid does not give specific
advice about the numbers of cups or ounces to have each day of specific
foods. That’s because it’s not meant to be a rigid road map, and the
amounts can vary depending on your body size and physical activity. It’s
a simple, general, flexible guide to how you should eat when you eat.
There’s just one basic guideline to remember: A healthy diet includes
more foods from the base of the pyramid than from the higher levels of
the pyramid. Within this guideline, however, there’s plenty of
flexibility for different styles of eating and different food choices. A
vegetarian can follow the Healthy Eating Pyramid by emphasizing nuts,
beans, and other plant sources of protein, and choosing non-dairy
sources of calcium and vitamin D; someone who eats animal products can
choose fish or chicken for protein, with occasional red meat.
Choosing a variety of fresh, whole foods from all the food groups
below the “Use Sparingly” category in the Healthy Eating Pyramid will
ensure that you get the nutrients you need. It will also dramatically
lower your salt intake, since most of the salt in the U.S. diet lurks in
processed food—canned soups, frozen dinners, deli meats, snack chips,
and the like.
Perhaps the only foods that are truly off-limits are foods that
contain trans fat from partially hydrogenated oils. Luckily, in the U.S.
and Canada, trans fats must be listed on nutrition labels. More and
more food manufacturers, restaurants, and even entire communities are
going trans fat-free, making it easier to avoid this health-damaging
type of fat.
Other Alternatives
The Healthy Eating Pyramid summarizes the best dietary information
available today. It isn’t set in stone, though, because nutrition
researchers will undoubtedly turn up new information in the years ahead.
The Healthy Eating Pyramid will change to reflect important new
evidence.
This isn’t the only alternative to the USDA’s MyPyramid. The Asian, Latin, Mediterranean, and vegetarian pyramids promoted by
Oldways Preservation and Exchange Trust
are also good, evidence-based guides for healthy eating. The Healthy
Eating Pyramid takes advantage of even more extensive research and
offers a broader guide that is not based on a specific culture. The
original Healthy Eating Pyramid is described in greater detail in
Eat, Drink, and Be Healthy: The Harvard Medical School Guide to Healthy Eating,
by Walter C. Willett, M.D. (the Fredrick John Stare Professor of
Epidemiology and Nutrition in the Departments of Nutrition and
Epidemiology at Harvard School of Public Health) with Patrick J.
Skerrett (published by Free Press, 2005).
Failing the Test
Back in the 1990s, the USDA’s Center for Nutrition Policy and
Promotion created the Healthy Eating Index “to measure how well American
diets conform to recommended healthy eating patterns.” (
3)
In its original form, this score sheet used five elements from the
longstanding USDA Food Guide Pyramid (number of daily servings of
grains, vegetables, fruits, meat, and dairy products) and five from the
1995 Dietary Guidelines for Americans (total fat in the diet, percentage
of calories from saturated fat, cholesterol intake, sodium intake, and
variety of the diet). A score of 100 meant following the federal
recommendations to the letter while a score of 0 meant totally ignoring
them. (The USDA has since
updated the score sheet to reflect the Dietary Guidelines for Americans 2005.)
To see how well the principles embodied in the Healthy Eating Pyramid
stacked up against the government’s advice, Harvard School of Public
Health researchers created an Alternate Healthy Eating Index with a
scoring system similar to the USDA’s index. They then compared the two
indexes, using information about daily diets collected from more than
100,000 female nurses and male health professionals taking part in two
long-term studies.
Men who scored highest on the USDA’s original Healthy Eating Index
(meaning their diets most closely followed federal recommendations)
reduced their overall risk of developing heart disease, cancer, or other
chronic disease by 11 percent over 8 to 12 years of follow-up compared
to those who scored lowest. Women who most closely followed the
government’s recommendations were only 3 percent less likely to have
developed a chronic disease. (
4)
In comparison, scores on the Alternate Healthy Eating Index did
appear to correlate more closely with disease in both sexes. Men with
high scores (those whose diets most closely followed the guidelines in
the Healthy Eating Pyramid) were 20 percent less likely to have
developed a major chronic disease than those with low scores. Women with
high scores lowered their overall risk by 11 percent. Men whose diets
most closely followed the Healthy Eating Pyramid lowered their risk of
cardiovascular disease by almost 40 percent; women with high scores
lowered their risk by almost 30 percent.
Julian
seemed to have been aware that Carlos was going to be good at commerce
and would educate him on business dealings. Although he was only 12
years old when his father died, Carlos inherited his fathers business
talents, whose work ethic and business acumen was extraordinary.
Carlos Slim has a mansion in Mexico City
where he has hosted American presidents and famous Mexican novelists.
He claims to live a rather rustic life, not traveling much and enjoying
baseball as he roots for the New York Yankees. Rather, he enjoys staying
at home and reading about the military strategies of Genghis Khan.
“All times are good time for those who know how to work and have the tools to do so.” – Carlos Slim
Provided:
Every organism needs to obtain energy in order to live. For example, plants get energy from the sun, some animals eat plants, and some animals eat other animals.
Subject:
A Food chain is the sequence of who eats whom in a biological community (an ecosystem) to obtain nutrition. A Food chain starts with the primary energy source, usually the sun or boiling-hot deep sea vents. The next link in the chain is an organism that make its own Food from the primary energy source -- an example is photosynthetic plants that make their own Food from sunlight (using a process called photosynthesis) and chemosynthetic bacteria that make their Food energy from chemicals in hydrothermal vents. These are called autotrophs or primary producers.
Next come organisms that eat the autotrophs; these organisms are called herbivores or primary consumers -- an example is a rabbit that eats grass.
The next link in the chain is animals that eat herbivores - these are called secondary consumers -- an example is a snake that eat rabbits.
In turn, these animals are eaten by larger predators -- an example is an owl that eats snakes.
The tertiary consumers are are eaten by quaternary consumers -- an example is a hawk that eats owls. Each Food chain end with a top predator, and animal with no natural enemies (like an alligator, hawk, or polar bear).
The arrows in a Food chain show the flow of energy, from the sun or hydrothermal vent to a top predator. As the energy flows from organism to organism, energy is lost at each step. A network of many Food Chains is called a Food web.
Trophic Levels:
The trophic level of an organism is the position it holds in a Food chain.
1. Primary producers (organisms that make their own Food from sunlight and/or chemical energy from deep sea vents) are the base of every Food chain - these organisms are called autotrophs.
2. Primary consumers are animals that eat primary producers; they are also called herbivores (plant-eaters).
3. Secondary consumers eat primary consumers. They are carnivores (meat-eaters) and omnivores (animals that eat XXXX animals and plants).
4. Tertiary consumers eat secondary consumers.
5. Quaternary consumers eat tertiary consumers.
6. Food Chains "end" with top predators, animals that have little or no natural enemies.
When any organism dies, it is eventually eaten by detrivores (like vultures, wormsand crabs) and broken down by decomposers (mostly bacteria and fungi), and the exchange of energy continues.
Some organisms' position in the Food chain can vary as their diet differs. For example, when a bear eats berries, the bear is functioning as a primary consumer. When a bear eats a plant-eating rodent, the bear is functioning as a secondary consumer. When the bear eats salmon, the bear is functioning as a tertiary consumer (this is because salmon is a secondary consumer, since salmon eat herring that eat zooplankton that eat phytoplankton, that make their own energy from sunlight). Think about how people's place in the Food chain varies - often within a single meal.
Numbers of Organisms:
In any Food web, energy is lost each time one organism eats another. Because of this, there have to be many more plants than there are plant-eaters. There are more autotrophs than heterotrophs, and more plant-eaters than meat-eaters. Although there is intense competition between animals, there is also an interdependence. When one species goes extinct, it can affect an entire chain of other species and have unpredictable consequences.
Equilibrium
Conclusion
As the number of carnivores in a community increases, they eat more and more of the herbivores, decreasing the herbivore population. It then becomes harder and harder for the carnivores to find herbivores to eat, and the population of carnivores decreases. In this way, the carnivores and herbivores stay in a relatively stable equilibrium, each limiting the other's population. A similar equilibrium exists between plants and plant-eaters