Functional
Foods — How They Fare in the New Pyramid
By David A. Mark, PhD
Today’s Dietitian
Vol. 7 No. 9 P. 30
Some functional foods are stars in the new food
guide pyramid, but others are still waiting in the wings.
Alice’s clients want to live forever. To do
so, they often ask Alice about what functional foods to eat to forestall
heart disease, cancer, dementia, and osteoporosis. Alice has a clear
idea about what is functional about “functional” foods
(and which ones are claiming more than they deliver), but she wants
to know whether the new USDA MyPyramid can be a helpful tool to
functional food recommendations for her clients.
MyPyramid does not cover diseases. Introduced in
April, the USDA MyPyramid food and exercise guide specifically states:
“The recommendations in the Dietary Guidelines and in MyPyramid
are for the general public over 2 years of age. MyPyramid is not
a therapeutic diet for any specific health condition. Individuals
with a chronic health condition should consult with a health care
provider to determine what dietary pattern is appropriate for them.”
Alice, our emblematic dietitian, is such a healthcare
provider. She knows that most adults in the United States have one
or more chronic health conditions that may benefit from a functional
food. What she will learn here is that some functional foods have
an FDA-approved health claim and also fall within the new USDA MyPyramid
food guidance system. These are easy to recommend with a clear conscience.
Other functional foods are beyond the pale, either because evidence
does not yet support FDA approval of a health claim on the label,
or because calories, fat, or sodium represent significant negatives.
These will need a critical evaluation and customized recommendation
to her clients and patients.
A Brief History
The USDA was founded in 1862 by President Lincoln to help farmers
who needed good seeds and information to grow their crops. Although
its prime directive is to support U.S. agriculture, which now represents
more than $500 billion in annual sales, the USDA has taken on other
responsibilities. It has periodically issued food consumption guidelines
dating as far back as 1916. The Basic Four Food Groups ‘box’
diagram of Dairy, Meat, Vegetables & Fruits, Bread & Cereal
was formalized in 1956. For the 35 years of its existence, it served
as an excellent teaching tool for children and adults. In a time
when many people still faced poverty and limited food choices, the
Basic Four promoted protein-, vitamin-, and mineral-rich foods.
When the Basic Four was established, obesity, heart
disease, diabetes, hypertension, and cancer were not considered
to be lifestyle influenced diseases. By the 1980s, the results of
the Bogalusa, Framingham, and other long-term population studies
had begun to define the connections between diet and disease. The
Basic Four plan could not be easily modified to cover foods to avoid.
Drafts of a new program, named the USDA Eating Right Pyramid, began
to circulate in 1988. The adoption of the food pyramid was delayed
until 1992 by debates between nutritionists and the meat/dairy industries.
The latter felt that the positioning of their products among the
foods to be consumed less frequently—ie, higher up the pyramid,
implying that those foods were unhealthy.
The Food Guide Pyramid (1992-2004) identified food
groups (now up to six) and set target ranges for the number of servings
per day. One pyramid was intended to fit all people, but the number
of servings was expected to accommodate needs for growth and physical
activity, or the difference in size between a small child and a
large adult. The small section at the peak of the pyramid was a
means of visually recommending lower intakes for fats, oils, and
sugar. Shortly after the Food Guide Pyramid was launched, in January
of 1993, the FDA approved the first set of health claims for food
labels. These included calcium for bones, fruits and vegetables
to reduce the risk of cancer and cardiovascular disease, and lower
fat intake for lower risk of cancer and cardiovascular disease.
All these health claims meshed with the Food Guide Pyramid recommendations.
Although barely into its teens, the Food Guide Pyramid
was officially replaced in April with the USDA MyPyramid program.
Like the earlier version, the new pyramid had a long gestation.
It was unveiled in draft form in September 2003 and underwent 20
months of public comments, revisions, lobbying, and redesign before
being introduced in Web site form on April 19. The new look does
away with servings. Instead, the width of the wedges is supposed
to convey proportional amounts in the diet. The pyramid is customized
to the Web site user’s body size and physical activity level
(hence “My” Pyramid). The amounts of food to be consumed
are expressed in ounces (grains and meat/beans) or cups (vegetables,
fruits, milk). Some recommendations are quite timid: “Know
the limits of fats, sugars, and salt.” Others are buried deep
within the MyPyramid.gov Web site. For example, it takes three clicks
to get inside the pyramid and learn that eggs are included in the
Meat & Beans group.
Functional Foods
While the USDA stayed with the Food Guide Pyramid from 1992 to 2005,
the FDA continued to approve label health claims for functional
foods, and beginning in 2000, started to allow food and supplement
qualified health claims, with statements signifying less than full
scientific consensus. Other functional foods have not yet been ruled
on by the FDA (either dossiers have been filed but not ruled on,
or not yet filed). The following sections address how the official
and unofficial functional foods fare within the MyPyramid program.
Briefly, the winners are dairy, whole grains, fruits, vegetables,
fish, and nuts. The losers are fruit juices, alcohol, chocolate,
olive oil, and eggs.
Winners
Dairy, dairy, dairy. The MyPyramid health statement is “Get
your calcium-rich foods,” but the category is titled “Milk.”
A Milk/Dairy group (including ice cream!) was with us from 1956
to 1991 as part of the Basic Four Food Groups. The Food Guide Pyramid
of 1992 had two to three servings per day of milk, yogurt, or cheese.
Now, the new MyPyramid calls for three servings per day of low-fat
or fat-free milk, yogurt, and other milk products. Deep within the
background material there is an allowance that other calcium-rich
foods can be substituted if dairy foods are not consumed. Calcium
supplements are not mentioned.
The reality of the supermarket cold case is that
fluid milk sales have declined by 33% over the past 50 years, abetted
recently by calcium-fortified soy-based beverages and calcium-fortified
fruit juices. Although the dairy industry hopes to prove that cow’s
milk contains compounds independent of calcium that have a health
benefit, especially for the controversial claim of body weight management,
the current FDA-approved health claim is for calcium.
The old pyramid called for six to 11 servings of
bread, cereal, rice, or pasta every day. The new pyramid calls the
category “Grains” and in the sample 2,000-calorie diet,
calls for 6 ounces every day of cereals, breads, crackers, rice,
or pasta. What is new is the recommendation that at least one-half
of the grain category be whole grains. The breakfast cereal industry
has given this a whole-hearted endorsement, and is heavily promoting
whole grain cereals.
Fruits and vegetables stay in the picture. The recommendations
are industry-friendly, in that they include fresh, frozen, canned,
or dried preparations. The 2 to 3 cups per day of each seems huge
in comparison with grains, but most of that volume is the naturally
occurring water content of fruits and vegetables (apples, for example,
are 85% water). The detailed material specifically recommends dark
green vegetables, orange vegetables, more use of beans, peas, and
lentils, and potassium-rich fruits. There is a muted recommendation
to limit the amount of potatoes, corn, and other starchy vegetables.
Nuts, or at least most tree nuts, achieved an FDA-approved
qualified heart health claim prior to the finalization of the MyPyramid
Guide. Ditto omega-3 fatty acids from fish. This appeared to be
enough to have nuts and fish land foursquare in the “Meat
and Beans” category. Strategies for use include, “Choosing
nuts as a snack, on salads, or in main dishes, to replace meat or
poultry, not in addition to these,” and “Selecting fish
… more often, especially fish rich in omega-3 fatty acids.”
Losers
The MyPyramid poster states, “Go easy on fruit juices.”
The associated educational materials define this as keeping the
amount of fruit juice consumed to less than one-half of the total
fruit intake. The pro-fruit rationale is for sources of fiber and
potassium, but does not go into the evidence for benefits of flavonoids
from blueberries, plums, cranberries, purple grapes, and other dark-colored
fruits and fruit juices. However, the light fruit juices (white
grape, apple, white cranberry) don’t have much going on beyond
sugar content, so maybe it’s just as well.
Alcohol is one of the few functional foods with
stronger proven negatives than positives. On the positive side of
the equation, when consumed in moderation the epidemiological evidence
is strong that alcohol has a cardiovascular benefit, and may have
an antidementia effect. Moderation is defined in the Dietary Guidelines
as up to one drink per day for women and up to two drinks per day
for men. A relatively recent meta-analysis of 26 population studies
reported a significant inverse association between light-to-moderate
wine consumption and vascular risk.1 The consensus is that there
is a benefit from alcohol regardless of type of beverage, but the
authors of the meta-analysis elsewhere speculate that “…it
is reasonable to speculate that the cardiovascular protective effects
of wine, observed in French and in other populations, may be attributed
in part to the antioxidant, vasorelaxant, and antithrombotic properties
of its polyphenolic components.”2 In a study conducted in
Italy, 15,807 people with an average age of 71 at time of admission
to hospitals were evaluated for cognitive impairment, which was
detected in 19% of alcohol drinkers and 29% of nondrinkers.3
On the negative side of the alcohol equation, more
than 100,000 Americans die of alcohol-related causes each year,
ranking alcohol third after tobacco and obesity as lifestyle related
contributors to mortality. Drinking more alcohol increases such
dangers as alcoholism, liver cirrhosis, high blood pressure, cancer,
obesity, stroke, traffic accidents, criminal activity, and suicide.4
The MyPyramid “key concepts for educators”
does not address any of the putative health benefits of alcohol,
only that consumption should be not at all or in moderation, and
within the 100 to 300 discretionary calories that most people have
in their daily calorie budget. One drink is defined as 12 fluid
ounces of beer, 5 ounces of wine, or 1.5 ounces of 80-proof distilled
spirits. Not counting the nonalcoholic components of mixed drinks,
these beverages fall into the range of 100 to 150 calories per drink,
so one to two drinks per day would use a typical person’s
discretionary calories—leaving no space for … chocolate.
Chocolate wants to join the list of functional foods
but needs better evidence and a means of addressing the negatives:
saturated fat, sugar, and calories. Clinical evidence supports the
theory that polyphenolic compounds in cocoa are responsible for
reducing the risk of heart disease. Given that milk chocolate bars
are only 10% cocoa (and dark chocolate bars, at least in the United
States, are only 15% cocoa), the best practical advice may be to
recommend a variety of polyphenol sources, including green tea (no
calories), rather than giving a blessing to unlimited chocolate
consumption. Per-capita consumption in the United States is roughly
12 pounds per year.
In late 2004, olive oil received a qualified health
claim from the FDA. The heart health benefit is attributed to the
monounsaturated fatty acids in olive oil. The FDA’s recommendation
is to replace a similar amount of saturated fat and not increase
the total number of calories per day.
Eggs are the Banquo’s ghost of high-quality
protein—buried in the MyPyramid food guide, but still with
us. Production in the United States has held close to 260 eggs per
capita for the past 20 years. Over that time, purchase as eggs-in-the-shell
decreased from 85% of the total to 70%, but use of eggs in baked
goods and other foods increased from 40 to 80 per year, or 30% of
the total. Given that there are now a slew of low-cholesterol egg-based
products on the market, not to mention cholesterol synthesis-lowering
drugs and cholesterol absorption-blocking functional foods, it is
surprising that one of the changes from the old pyramid to MyPyramid
was that eggs disappeared from the pyramid, or at least from the
front page (eggs do show up in the Meat & Beans section several
clicks into the Web site).
Exercise
There is no U.S. Department of Exercise. Perhaps this is why the
physical activity part of the USDA MyPyramid program is off to the
side, in black and white, with an ectomorphic stick figure going
up stairs two at a time.
The MyPyramid recommendation is to “be physically
active for at least 30 minutes most days of the week.” How
does this compare with other recommendations, and with reality?
The 2005 Dietary Guidelines recommend at least 30 minutes of moderately
intensive physical activity most days of the week to reduce the
risk of chronic diseases in adulthood, with greater health benefits
reached with longer duration and/or more vigorous intensity. To
maintain adult weight, the guidelines recommend 60 minutes of moderate
to vigorous exercise most days of the week. To promote and sustain
weight loss, 60 to 90 minutes of daily exercise. The Guidelines
recommend a mix of endurance, resistance, and flexibility exercise.
According to the Centers for Disease Control and
Prevention just under 50% of adults in the United States achieve
the level of physical activity recommended by MyPyramid. Fifteen
percent are deemed “inactive,” meaning less than 10
minutes per week of moderate or vigorous exercise. Physical activity
is defined in these surveys as including household chores, walking
in the course of daily life, and leisure-time activities such as
exercise, sports, or gardening. Nearly 25% of adults have no leisure-time
physical activity in their lives. Clearly, even the modest levels
of exercise recommended in MyPyramid are beyond most people’s
reach. This is a disaster, as exercise is proven to reduce the risk
of cardiovascular disease, diabetes, certain types of cancer, hypertension,
obesity, osteoporosis, arthritis, depression, and other conditions.5,6
Back to Alice
The new MyPyramid, despite its flaws, incorporates most of the functional
foods supported by good clinical data (and the FDA), albeit with
a favorable tilt towards dairy. For the dairy adverse, Alice should
recommend beverages fortified with calcium and vitamin D, or a calcium
and D dietary supplement. Clients with an interest in unapproved
functional foods will need to be educated about relative strength
of evidence, and about caloric compensation for whatever does not
fit within the day’s discretionary calories. Finally, Alice
needs to stress exercise!
— David A. Mark, PhD, is president of dmark
consulting LLC, a provider of research management services to functional
food and dietary supplement companies.
References
1. Di Castelnuovo A, Rotondo S, et al. Meta-analysis of wine and
beer consumption in relation to vascular risk. Circulation.
2002;105:2836-2844.
2. Rotondo S, Di Castelnuovo A, de Gaetano G. The
relationship between wine consumption and cardiovascular risk: From
epidemiological evidence to biological plausibility. Ital Heart
J. 2001;2:1-8.
3. Zuccala G, Onder G, et al. Dose-related impact
of alcohol consumption on cognitive function in advanced age: Results
of a multicenter study. Alcohol Clin Exp Res. 2001;25:1743-1748.
4. National Institute on Alcohol Abuse and Alcoholism.
Available at: http://www.niaaa.nih.gov.
5. The President’s Council on Physical Fitness
and Sports; Physical Activity Fact Sheet. Available at: http://www.fitness.gov/resources_factsheet.htm.
6. The President’s Council on Physical Fitness
and Sports; Publications. Available at: http://www.fitness.gov/home_pubs.htm.
Resources
www.mypyramid.gov
Official site of the MyPyramid.gov program “STEPS TO A HEALTHIER
YOU”
www.mypyramid.org
This is a spoof site, identifying itself as a program of the “United
States Department of Agribusiness.” It is mildly funny, but
not useful.
www.healthierus.gov/dietaryguidelines
Link to the Dietary Guidelines for Americans 2005, released in January
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