Transcript BIOL 103 Ch 3 Functional Foods and Dietary Supplements_SS15

Complementary Nutrition:
Functional Foods and Dietary
Supplements
BIOL 103, Chapter 3
Today’s Topics
• Functional Foods
– Phytochemicals
• Food Additives
– Types & Regulations
• Dietary Supplements:
– Vitamins and Minerals
– Natural Health Products
– Regulations and Claims
• Complementary and Alternative Medicine
Functional Foods
• What is it?
– Functional foods: a food that may provide a
health benefit beyond basic nutrition.
• Foods can be classified as functional foods if
they contain:
– naturally-occurring phytochemicals
– “vitamins, bacteria, fiber, etc.” – fortification
Phytochemicals
• Phytochemicals are substances that have
health benefits, but they may not be essential
to life
– makes food functional
– act as Antioxidants
• Neutralize free radicals
• Reduce heart disease and cancer risk
– Found naturally in fruits, vegetable, whole grain,
legumes, and wine
Examples and Benefits of
Phytochemicals (PS#3, Q1)
• Table 3.1: Examples of Functional Components
1. Lycopene (prostate health)
2. Omega-3 fatty acids (heart, mental and visual
function)
3. Isoflavones/soy products (bone, brain, immune
system, menopause)
4. Probiotics (gut health, immune system)
5. Flavonoids (cellular antioxidants defenses)
Foods Enhanced with Functional
Ingredients
• Foods can be enhanced
with functional
ingredients during
processing
Speaking of antioxidants…
What is an antioxidant?
What is a free radical and
what does it do?
– While the body metabolizes oxygen, 1-2% of
cells will get damaged in the process  turn
into free radicals (“active oxidants”)
– Normally, free radicals oxidize/damage; this
may lead to chronic diseases:
•
•
DNA, cell structures  cancer and cell aging
Lipids  heart disease
Formation of Free Radicals
• Cellular and environmental factors can
cause free radicals to form
• Free radicals can DNA damage
How do phytochemicals work to
prevent chronic disease?
• Phytochemicals such as
flavonoids provide
antioxidant effects
• By neutralizing free
radicals, antioxidants
can
How do phytochemicals work to
prevent chronic disease?
• Phytoestrogen or “dietary
estrogen” is a type of
phytochemical with
estrogenic/anti-estrogenic
effects.
• Phytoestrogens either
modify estrogen
metabolism or block effect
of estrogen on cell growth
Everything in moderation…
Regulatory Issues for Functional Foods
• To monitor the products for consumption, FDA
categorizes into the following:
1. [Conventional] Food include:
1.
2.
the product that we eat/drink
components that make up the product.
2. Drug: substance intended to diagnose, cure, mitigate,
treat, prevent disease
3. Dietary Supplements: products meant to supplement
a diet, but are not conventional foods.
4. “Food Additives”
Food Additives
(PS#3, Q2)
• Additives: substances added to food for
various functions
• 2 types of additives:
1. Direct
1. Indirect
5 Purposes of Direct Additives
1. Maintain product
consistency
2. Improve or maintain
nutritional value
3. Keep food appetizing and
wholesome
4. Provide leavening or
control acidity and
alkalinity (e.g. yeast,
baking powder, baking
soda)
5. Enhance flavor or color
Vitamins as Food Additives in Alcohol?
• Alcohol Metabolism
Enhanced Alcoholic Beverages
What’s the idea behind it?
– Vodka/Beer + Vitamin B – in
hopes of speeding up the
metabolism via Vitamin B 
alcohol is processed faster
 reduced chance of a
hang-over
Why no advertising?
– For chronic, heavy drinkers
 vitamin toxicity (e.g. too
much B6 = neurological
symptoms)
Regulation of Food Additives
by the FDA
• Additives fall into 4 Regulatory Categories:
1.
2.
3.
4.
Food Additives
Color Additives
Generally Recognized as Safe (GRAS) substances
Prior-sanctioned substances
Regulation of Food Additives by the
FDA (PS#3, Q3)
1. Food Additives
•
•
Must have FDA approval
Manufacturer must prove safety
2. Color Additives: any dye/pigment or other
substance that can impact color when added to
a food, drug, cosmetic, or to a human body.
• Certified color additives used in foods are man-made.
Who loves Orange Juice?
• Processed orange juice is generally
flavorless because oxygen is
removed from them (prevents
spoiling)
• So, juice companies hire flavor and
fragrance companies to make flavor
packs to make the juice taste fresh.
– Flavor packs are not listed in ingredient
labels b/c they are technically derived
from orange essence and oil.
– Different fragrance chemicals are used
in different countries
Regulation of Food Additives by the
FDA (PS#3, Q4)
3. Generally Recognized as Safe (GRAS): substances
that can be added to foods by manufacturers
without establishing rigorous scientific tests.
• “additives that are generally thought by experts to be
safe to eat”
• e.g. salt, sugar, spice, MSG…
4. Prior-sanctioned Substances: substances that FDA
and/or USDA determined were safe to use in
specific foods before Sept 1958.
MSG
• MSG: monosodium glutamate
• What is it?
– Flavor enhancer found in many
Asian cuisine, canned vegetables,
processed meat.
• Is it really harmful?
– People report short-term side
effects such as headache, flushing,
sweating, nausea, chest pain…
• What does the research say?
– Researchers have yet to find a solid
evidence that link these symptoms
with MSG. However, because MSG
topic is still controversial, the FDA
requires that MSG is listed in the
labels.
Delaney Clause (PS#3, Q4)
• Delaney Clause: food and color additives
cannot be approved if they cause cancer in
humans or animals.
– Agree or Disagree?
• Controversy associated with amount tested in
animals vs. actual human consumption
Strategies for Functional Food Use
• Stick with science
– Eat fruit and vegetables
– Eat nutrition-fortified products as needed
– Read, read, read (scientific articles)
– Be critical of advertising and hype
• “if it sounds too good to be true, it probably is!”
Dietary Supplements: Vitamins and
Minerals
• Various forms of dietary supplements:
– Examples: Vitamins, minerals, amino acids, herbs,
glandular extracts, enzymes, etc.
• 2 levels of vitamin and mineral
supplementation:
1. Moderate doses: within the range of the Daily
Values (DVs)
2. Megadoses: high levels beyond DVs
Who should seek moderate
supplementation?
• Those with increased
nutrient needs and/or
poor intake include:
1. Women of childbearing
age who may become
pregnant
2. Pregnant and
breastfeeding women
3. Women with heavy
menstrual losses
4. Children (picky eaters)
Who should seek moderate
supplementation?
5. People with severe food restriction
5. Strict vegetarians who do not eat animal foods
and dairy products
5. Elderly
When looking for moderate
supplementation…
• If you are looking for
moderate
supplementation:
1. Look for brands that
contain at least 20
vitamins and minerals
2. No more than 100% of
its DV
Megadoses in Conventional Medical
Management
• Situations in which doctors are likely to prescribe
megadoses:
– Treatment of severe deficiencies
– Malabsorption syndromes: when individual cannot
absorb enough nutrients in their gut.
– Drug interactions
• A vitamin at megadose levels can have “drug-like
effects,” thus, patients may suffer serious sideeffects.
– Example: Niacin at 100x the usual level can act as a
drug to lower blood lipid levels.
Megadosing Beyond Conventional
Medicine: Orthomolecular Nutrition
• Orthomolecular
medicine: the
preventive or
therapeutic use of highdose vitamins to treat a
disease.
– Linus Pauling, 1968
– Achieving the “optimal
nutrition” levels
• Q: Does consuming a lot
of Vitamin C prevent cold?
Drawbacks of Megadoses
(PS#3, Q5)
1. Can act as a drug  adverse side effects
2. Can create deficits of other nutrients by
interfering with absorption of others
– Nutrient-nutrient interactions: Zn, Fe, Cu, Ca
3. Can interfere with functions of other nutrients
– Ex: Megadoses of Vitamin E interferes with blood
clotting functions of Vitamin K
•
In general, more dangerous to megadose with
minerals than vitamins
Are these products actually
“natural”?
Dietary Supplements: Natural Health
Products
• Natural health products
– Used in Herbal therapy (phytotherapy)
– Little scientific evidence of efficacy, safety
• All foods are made up of chemical components
– Advertisements use “100% Natural” (2nd highest claim
on food labels, 2008).
– The general American consumer believes that natural
foods are more “wholesome, nutritious, and healthy.”
• Traditional Herbalists vs. Conventional Medicine
Helpful Herbs, Harmful Herbs
• NCCAM and NIH mission: to investigate using
science to make sure herbs, herbal therapy and
related practices are safe and healthy
• Main idea: “if strong enough to help, strong
enough to hurt”
1.
2.
3.
4.
Not all herbs are good for you
Poor quality
Too much herbs may cause negative effects
Herbs may interact with doctor prescribed
medicines
• Table 3.5 Herb-Drug Interactions
Dietary Supplement in the
Marketplace
• Manufacturers have freedom of speech and
press.
– Thus, they are allowed to to a wide variety of
claims for product effects without having to
provide scientific evidence to support those
claims.
FTC and Supplement Advertising
• FTC (Federal Trade Commission) is responsible
for ensuring that advertisements and
commercials are truthful and do not mislead.
– Depends on and encourages self-monitoring by
the supplement industry
• FTC’s “Operation and Cure All” – online
version, to search for false claims about the
supplement
FDA and Supplement Regulation
• FDA has primary responsibility for regulating
labeling and content of dietary supplements
under 1994 Dietary Supplement Health and
Education Act (DSHEA)
• So how do you know if it’s a dietary
supplement?
– Dietary supplements: “products that are taken by
mouth that contain a dietary ingredient.”
The FDA and Supplement Regulation
(PS#3, Q6)
• Dietary supplements and their ingredients are
NOT drugs and are NOT additives.
– Drugs require extensive tests for safety,
effectiveness, dosing, etc., BEFORE and AFTER
marketing.
– Food additives also require approval BEFORE
marketing
• Supplement approval by FDA is not required
– Thus, FDA must prove it isn’t safe AFTER it is on
the market…
Supplement Labels
• Mandatory requirements
are:
1. Name of Dietary
Supplement
2. Amount of dietary
supplement
3. Nutrition Labeling
4. The Ingredient List
5. Name and place of
business of the
manufacturer, packer,
or distributor.
Dietary Supplements and Claims
1. Health claims (associated with disease/health
condition)
1. Structure/functional claims
– Must have “disclaimer” statement on label: “this
statement has not been evaluated by the FDA.”
2. Nutrient content claims
– Consistent with definitions approved for foods
Choosing Dietary Supplements
• Ask the following questions:
– Is the quantity enough to have an effect?
– Is the product new to you?
– What is its bioavailability?
• There is little data on bioavailability of herbal
preparations and other types of non-nutrient
supplements.
Choosing Dietary Supplements
• Ask the following questions (cont.):
– Can it interact with any prescription or other
medications you are taking?
– Does the product promise too much?
– Who is selling the product?
• Multilevel marketing: system of selling in which each
salesperson recruits assistants who then recruit others
to help them. The person at each level collects a
commission on sales made by later recruits.
Choosing Dietary Supplement
• U.S. Pharmacopea (USP)
is a verification mark that
verifies:
1. Contains ingredients
declared on the label
2. Contains the amount or
strength of ingredients
declared on the label
3. Meets requirements for
limits on potential
contaminants
4. Has been manufactured
properly by complying
with USP and FDA
manufacturing standards
Fraudulent Products
• ~1/3 of herbal supplements on the market may
be outright fraudulent.
• Remember, dietary supplements, unlike foods
and drugs, are not reviewed/tested to be
effective by the FDA.
• Examples of potential warning signs:
– Claim to be alternatives to FDA-approved drugs
– Claim to be legal alternative to steroids
– Marketed primarily in a foreign language/mass emails
Complementary and Alternative
Medicine (CAM)
• Complementary and Alternative Medicine
(CAM): therapies and treatment outside the
medical mainstream.
– Alternative  practices used in place of
conventional medicine.
– Complementary  practices used in addition to
conventional medicine.
• 40% adults and 12% children in America use
some form of CAM therapy.
CAM and Nutrition
• Alternative nutrition
practices include diets to
prevent and treat diseases
not shown to be diet-related
• Usually alternative nutrition
practices are:
– Overly restrictive
– Depart from established
guidelines (My Plate)
– Lack rigorous scientific
evidence
– Reliance on raw foods,
herbal/botanical supplements,
megadoses of vitamin/mineral
supplements
CAM and Nutrition
• Nutrition in CAM
1. Vegetarian diets (alternative)
• When individual go “meatless” to treat a disease
2. Macrobiotics diet (alternative)
• Emphasizes fresh and unprocessed food, low-fat, whole
grains, vegetables, and less fluids.
Food Restriction and Food
Prescriptions
• Many societies use dietary changes to treat or
prevent illness
– The treatments are different  diets are based on
cultural factors than science.
• Fad diets most often eventually fail because
they do not work.
– The few that prove effective and have a scientific
basis become integrated into conventional
nutrition and diet therapy.