The Ultimate Guide to Choosing WordPress Pros and Cons
Lec 6 consumer nutrition 2
1. Community and public health
nutrition
6-Consumer awareness 2
a) Food additives
b) Anti nutrients
Prepared by; Dr. Siham Gritly
University of Bahri
"All things are poisons; nothing is without poison;
only the dose determines whether there is a harmful
effect“. Paracelsus (16th Century Philosopher)
1Dr. Siham Gritly
2. Glossary
• additives: substances not normally consumed as foods but
added to food either intentionally or by accident.
• preservatives: antimicrobial agents, antioxidants, and other
additives that retard spoilage or maintain desired
qualities, such as softness in baked goods.
• generally recognized as safe (GRAS): food additives that
have long been in use and are believed to be safe. First
established by the FDA in 1958,
• Delaney Clause: a clause in the Food Additive Amendment to
the Food, Drug, and Cosmetic Act that states that no substance
that is known to cause cancer in animals or human beings at
any dose level shall be added to foods
•
2Dr. Siham Gritly
3. Glossary
• margin of safety: when speaking of food additives, a
zone between the concentration normally used and
that at which a hazard exists. For common table
salt, for example, the margin of safety is 1/5 (five
times the amount normally used would be
hazardous).
• intentional food additives: additives intentionally
added to foods, such as nutrients, colors, and
preservatives.
• indirect or incidental additives: substances that
can get into food as a result of contact during
growing, processing, packaging, storing, cooking, or
some other stage before the foods are consumed; 3Dr. Siham Gritly
4. Glossary
• Nitrites: salts added to food to prevent
botulism. One example is sodium
nitrite, which is used to preserve meats.
• Nitrosamines; derivatives of nitrites that may
be formed in the stomach when nitrites
combine with amines. Nitrosamines are
carcinogenic in animals.
• Bacteriophages; viruses that infect bacteria
to prevent spoilage.
Dr. Siham Gritly 4
5. Glossary
• genotoxicant is a substance that mutates or
damages genetic material
• Phytochemicals: nonnutrient compounds
found in plant-derived foods that have
biological activity in the body.
• Antinutrients are natural or synthetic
compounds that interfere with the absorption
of nutrients .
• carcinogen is a substance that causes cancer,
Dr. Siham Gritly 5
6. Food additives
• Food additives are substances added to food
to preserve flavor or enhance its taste and
appearance.
• Most additives are preservatives that help
prevent spoilage during the time it takes to
deliver foods long distances to grocery stores
and then to kitchens.
6Dr. Siham Gritly
7. Some of food additives found in food
Dr. Siham Gritly 7
9. • Some act as Antimicrobial Agents; The most
widely used antimicrobial agents are ordinary
salt and sugar.
• Salt has been used throughout history to
preserve meat and fish;
• sugar serves the same purpose in canned and
frozen fruits and in jams and jellies.
• Both exert their protective effect primarily by
capturing water and making it unavailable to
microbes.
Dr. Siham Gritly 9
10. • Other antimicrobial agents, the nitrites, are
added to foods for three main purposes:
• to preserve color,
• to enhance flavor by inhibiting
rancidity, especially in cured meats and
poultry;
• to protect against bacterial growth
Dr. Siham Gritly 10
11. • Some reduce the risk of foodborne illness (for
example, nitrites used in curing meat prevent
poisoning from the botulinum toxin).
• Others enhance nutrient quality (as in vitamin
D–fortified milk).
Dr. Siham Gritly 11
12. The GRAS (generally recognized as safe)
• generally recognized as safe (GRAS), based
either on their extensive, long-term use in
foods or on current scientific evidence.
• Several hundred substances are on the GRAS
list, including such items as
salt, sugar, caffeine, and many spices.
Dr. Siham Gritly 12
13. The Delaney Clause
• a clause in the Food Additive Amendment to
the Food, Drug, and Cosmetic Act that states
no substance that is known to cause cancer in
animals or human beings at any dose level
shall be added to foods
Dr. Siham Gritly 13
14. • the FDA prefers to believe additives (and
pesticides and other contaminants) safe if
lifetime use presents no more than a one-in-a-
million risk of cancer to human beings.
• Thus, instead of the “zero-risk” policy of the
Delaney Clause, the FDA uses a “negligible-
risk” standard,
Dr. Siham Gritly 14
15. Margin of Safety
• To determine risks of an additive, researchers
feed test animals the additive at several
concentrations throughout their lives.
• The additive is then permitted in foods in
amounts 100 times below the lowest level that
is found to cause any harmful effect, that is, at
a 1/100 margin of safety.
Dr. Siham Gritly 15
16. Risks versus Benefits
• additives would not be added to foods if they
only presented risks.
• general, additives are used in foods when they
offer benefits
• in the case of color additives only enhance
appearance but do not improve health or
safety
Dr. Siham Gritly 16
17. • the FDA finds it worth taking the small risks
associated with the use of nitrites on meat
products, for example, because nitrites inhibit
the formation of the deadly botulinum toxin.
Dr. Siham Gritly 17
18. Benefit of food additives
Without additives, bread would quickly get
moldy, and salad dressing would go rancid
Dr. Siham Gritly 18
Ref. Ellie Whitney and Sharon
Rady Rolfes; Under standing
Nutrition, Twelfth Edition. 2011,
2008 Wadsworth, Cengage
Learning
19. • The FDA also requires that additives not be
used:
• To disguise faulty or inferior products
• To deceive the consumer
• When they significantly destroy nutrients
• When their effects can be achieved by
economical, sound manufacturing processes
Dr. Siham Gritly 19
20. Intentional Food Additives
• Intentional food additives are added to foods
to give them some desirable characteristic:
• resistance to spoilage,
• color, flavor, texture,
• stability,
• nutritional value.
20Dr. Siham Gritly
21. Intentional Food Additives
Ellie Whitney and Sharon Rady Rolfes; Under standing Nutrition, Twelfth Edition.
2011, 2008 Wadsworth, Cengage Learning
Food Additive Purpose Common Examples
Antimicrob
ial agents)
Prevent
microorganisms
from growing
Salt, sugar, nitrites and
nitrates (such as sodium
nitrate
Antioxidants Delay or prevent
rancidity of fats
and other damage
to foods caused by
oxygen
Vitamin C (ascorbic acid, sodium
ascorbate), vitamin E
(tocopherol), sulfites, synthetic
antioxidants butylhydroxyanisole
(BHA) and butylhydroxytoluene
(BHT)
21Dr. Siham Gritly
23. Intentional Food Additives
Food Additive Purpose Common Examples
Emulsifier
s and
gums
Thicken,
stabilize, or
otherwise
improve the
consistency
Emulsifiers: lecithin, mono- and
diglycerides Gums: agar,
alginates (brown algae),
carrageenan(extracted from red
seaweeds), locust bean, psyllium,
pectin, xanthan gum, gum arabic,
cellulose derivatives
Nutrients
(vitamins
and
minerals)
Improve the
nutritive
value
Thiamin, niacin, riboflavin, folate, iron
(in grain products); iodine (in salt);
vitamins A and D (in milk); vitamin C
and calcium (in fruit drinks); vitamin
B12(in vegetarian foods)
23Dr. Siham Gritly
25. Psyllium and psyllium seeds
Dr. Siham Gritly 25
the combination of low fat
diet, low in saturated fats and
cholesterol plus psyllium, can
reduce total cholesterol levels by
4% and low density lipoprotein
(LDL) cholesterol by 7%. The
soluble fiber in psyllium reduces
absorption of blood cholesterol and
bile acids from the intestine and
that in turn lowers blood
cholesterol levels.
27. Indirect Food Additives
• Indirect or incidental additives find their way
into foods during harvesting, production,
processing, storage, or packaging.
• Incidental additives may include tiny bits of
plastic, glass, paper, tin, and other substances
from packages as well as chemicals from
processing, such as the solvent used to
decaffeinate coffee.
Dr. Siham Gritly 27
28. Example of Indirect or incidental additives
Ref WHO 2013
• Acrylamide (C3H3ONH2) is a chemical that is
produced naturally in certain foods when they are
cooked at high temperatures.
• It is also manufactured industrially for use in the
production of polyacrylamide gels, which are
used for various purposes, including the treatment
of drinking-water and wastewater.
• Acrylamide is known to cause cancer in animals
and, in high doses, can cause nerve damage in
humans.
Dr. Siham Gritly 28
29. • Acrylamide; compound that forms when
carbohydrate-rich foods containing sugars and
the amino acid asparagine are cooked at high
temperatures
• Common foods containing acrylamide:
• French fries
• Potato chips
• Breakfast cereals
• Cookies
Dr. Siham Gritly 29
30. • Food Packaging
• The FDA ensures the safety of food
packaging and assesses whether packaging
materials might migrate into foods.
• These materials, known as ―food contact
substances,‖ include coatings on can
interiors, plastics, papers, and sealants.
Dr. Siham Gritly 30
31. • Dioxins
• dioxins is a class of chemical pollutants created
as by-products of chemical manufacturing,
burning, chlorine bleaching of paper pulp, and
other industrial processes.
• Scientists suggested that dioxins are extremely
toxic and are likely to cause cancer in humans
• Dioxins persist in the environment and
accumulate in the food chain
Dr. Siham Gritly 31
32. • Examples; Coffee filters, milk cartons, paper
plates, and frozen food packages, if made
from bleached paper,
• Human exposure to dioxins comes primarily
from foods such as beef, milk
products, pork, fish, and shellfish
Dr. Siham Gritly 32
33. • Decaffeinated Coffee Many consumers have
tried to eliminate caffeine from their diets by
selecting decaffeinated coffee.
• To remove caffeine from coffee
beans, manufacturers often use methylene
chloride in a process that leaves traces of the
chemical in the final product.
• People are exposed to much more methylene
chloride from other sources such as hair sprays
and paint-stripping solutions.
Dr. Siham Gritly 33
34. • Hormones are a unique type of incidental
additive in that their use is intentional, but
their presence in the final food product is not.
• The FDA has approved about a dozen
hormones for use in food-producing animals,
• hormone treated animals produce leaner
meats, and dairy cows produce more milk.
Dr. Siham Gritly 34
35. • Antibiotics Like hormones, antibiotics are also
intentionally given to livestock, and residues
may remain in the meats and milks.
• people consuming these foods receive tiny doses
of antibiotics regularly, and those with sensitivity
to antibiotics may suffer allergic reactions.
• To minimize drug residues in foods, the FDA
requires a specified time between the time of
medication and the time of slaughter to allow for
drug metabolism and excretion.
Dr. Siham Gritly 35
36. Natural Toxicants in Foods
• Plants may serve as poisons; for
example, hemlock, a member of the parsley
family, has been known as a deadly poison.
• Most chemicals that are natural poisons
produced by the plant forms part of its defense
mechanism against herbivores and pathogens.
Dr. Siham Gritly 36
37. • A system within cells (p-glycoproteins), found
especially in the mucosa of the gastrointestinal
tract (esophagus, stomach and colon), protects
against toxic substances in plants, bacteria and
fungi
• Natural toxicants include the goitrogens in
cabbage, cyanogens in lima beans, and
solanine in potatoes and others
37Dr. Siham Gritly
38. Goitrogens
• Poisonous mushrooms are a familiar example
of plants that can be harmful when eaten.
• Cabbage, turnips , mustard
greens, , brussels sprouts
cauliflower , broccoli, kohlrabi
, and radishes contain small quantities of
goitrogens—compounds that can enlarge the
thyroid gland
38Dr. Siham Gritly
40. Cyanogens
• Cyanogens inactive compounds that produce
the deadly poison cyanide upon activation by a
specific plant enzyme.
• Lima beans, cassava and fruit seeds such as
apricot pits contain cyanogens
40Dr. Siham Gritly
42. • Dozen of seeds if eaten can be fatal to a small
child.
• the most infamous cyanogen in seeds is
laetrile; a compound mistakenly represented
as a cancer cure.
• laetrile kills cancer, but only at doses that kill
the person, too.
Dr. Siham Gritly 42
43. Solanine; Average solanine content: 8 mg/100 g
potato. Toxic solanine dose: 20 to 25 mg/100 g
potato
• potato contains many natural poisons including
solanine, a powerful narcotic-like substance.
• Most of a potato’s solanine is found in the sprout and
in the green layer that develops just beneath the skin.
• Solanine poisoning is extremely
rare, however, because the small amounts of solanine
normally found in potatoes are harmless—even when
the potato skin is eaten. Solanine can be toxic, when
consumed in large quantities.
Dr. Siham Gritly 43
44. • Cooking does not destroy solanine, but it can
be removed by peeling the potato.
• Found also in apples, egg plants, roots and
leaves of tomatoes and sugar beet roots
• Symptoms of solanine poisoning include
gastrointestinal disturbances and neurological
disorders.
Dr. Siham Gritly 44
45. • Hormone disrupters are chemicals that affect
human or animal health by interfering with
normal hormonal processes
• Example; Oestrogens: at least 50 plants are
known to contain chemicals that have
oestrogenic activity, including carrots, soya beans,
wheat, rice, oats, barley , potatoes, apples,
cherries, plums and wheat germ.
• Oestrogens are also present in vegetable oils such
as cotton seed, sunflower, corn, linseed, olive and
coconut oils.
Dr. Siham Gritly 45
46. • Gossypol: this is the yellow colouring of
cotton, Gossypium.
• When ingested, the results are depressed
appetite and loss of body weight, cardiac
irregularity and circulatory failure or
pulmonary oedema.
• A major source of gossypol in the diet is
cotton seed oil, which may be found in salad
oil, margarine and shortening.
Dr. Siham Gritly 46
48. • Myristicin: hallucinogenic chemical
produced by, celery, parsley, parsnip, mint and
nutmeg.
• It is said that as little as 500 mg of raw nutmeg
may produce psychoactive symptoms,
• while 5–15 mg of powdered nutmeg may
result in euphoria, hallucinations and a dream-
like feeling, followed by abdominal
pain, depression and stupor (coma)
Dr. Siham Gritly 48
50. Carcinogens
A carcinogen is a substance that causes cancer, and a
genotoxicant is a substance that mutates or damages genetic
material
• Safrole is a carcinogen found in several
oils, including oil of sassafras, camphor and
nutmeg.
• Safrole has been found in 53 plant species and in
ten plant families, and has been shown to produce
liver cancer when sufficient is added to a rat diet.
• Black pepper contains small amounts of safrole
and larger amounts of piprine, which has been
shown to be carcinogenic to mice.
50Dr. Siham Gritly
52. • Furanocoumarins are carcinogenic chemicals
produced by celery, parsley and parsnip. The
concentration in these plants is low, but may
increase in diseased plants.
• Cycasin is found in cycads, which are important
sources of starch for tropical and subtropical
populations. Such compounds can produce
liver, kidney, intestinal and lung cancers in rats.
52Dr. Siham Gritly
53. • Mutagens: the cooking and processing of
meat and fish at high temperatures results in
heterocyclic amines with mutagenic and
carcinogenic effect
53Dr. Siham Gritly
54. • Epichloro-hydrin Carcinogens in tea bags
• Some tea bags are made using a wet paper
strength reinforcing coating using
epichlorohydrin, which is known to be
carcinogenic.
• epichlorohydrin found also in coffee filters,
sausage/salami casings have the same issues.
• use loose leaf tea or make sure the tea bags
don't use epichlorohydrin
Dr. Siham Gritly 54
55. Anti-nutrients
Dr. Siham Gritly 55
Anti-nutrients are,
compounds which prevent
the nutritive value of foods
from being effective, either;
by preventing the
absorption of nutrients,
Or by being toxic
themselves,
56. Phytate and oxalates
and their interfering with nutrients
• Oxalates and phytates belong to a group of anti-
nutrients.
• phytates has a strong binding affinity to minerals
such calcium, magnesium, iron, copper and zinc
• This results in precipitation, making the minerals
unavailable for absorption in the intestines.
• Phytic acids are common in the nuts, seeds and
grains
56Dr. Siham Gritly
57. • Oxalates have an adverse effect of binding to
essential minerals like calcium, magnesiom and
iron
• oxalic acid presents in many plants, particularly
in members of the spinach family. Oxalates bind
to calcium and prevent its absorption in the
human body
• accumulate in body tissues, causes toxicity over
time
• They also bind to calcium to form calcium
oxalate, which can then easily settle out as
sediments from the urine, causing kidney stones.
57Dr. Siham Gritly
58. short list of high oxalate foods
Dr. Siham Gritly 58
Swiss ChardSpinach
Plantains
Almonds
CashewsSesame Seeds
59. Summary of Some of anti-nutrients compound and their
effects
Antinutrient Source of food Activities in the body
Phytate and oxalic
acid
spinach, broccoli inhibits mineral absorption
Flavonoids
tannins
tea, coffee, wine
reduce the absorption of
iron and zinc
inhibits mineral absorption
Protein, trypsin
inhibitors and
Lectins
beans, wheat, Castor
Beans
inhibits digestive enzymes
glucosinolates
broccoli, brussel sprouts,
cabbage and cauliflower.
prevent the uptake of
iodine , affecting the
function of the thyroid and
thus are considered
goitrogensDr. Siham Gritly 59
60. Reduce phytates and oxalates effects
Boiling and then discarding the water, or soaking and
discarding the soaking water, can help reduce both
phytates and oxalates
other traditional methods of food preparation such as
fermentation, cooking, malting reducing certain
antinutrients
Dr. Siham Gritly 60
broccolispinach
61. • 1997-2012 HealthCheck Systems
• Sareen Gropper, Jack Smith and James Groff, Advanced Nutrition and Human
Metabolism, fifth ed. WADSWORTH
• Melvin H Williams 2010; Nutrition for Health, Fitness and Sport. 9th ed, McGraw
Hill
•
• Heymsfield, SB.; Baumgartner N.; Richard and Sheau-Fang P. 1999. Modern
Nutrition in Health and Disease; Shils E Maurice, Olson A. James, Shike
Moshe and Ross A. Catharine eds. 9th edition
• Guyton, C. Arthur. 1985. Textbook of Medical Physiology. 6th edition, W.B.
Company
• FAO/WHO/UNU expert consultation (WHO, 1985) report
• Ellie Whitney and Sharon Rady Rolfes; Under standing Nutrition, Twelfth Edition.
2011, 2008 Wadsworth, Cengage Learning
61Dr. Siham Gritly
62. • Health implications of acrylamide in food.
Joint FAO/WHO
consultation, Geneva, Switzerland, 25 - 27
June 2002
Dr. Siham Gritly 62
63. • parsley
• , camphor and nutmeg
• by celery, parsley
and parsnip
• , cherries, plums
• , linseed
• sassafras
• locust bean
Dr. Siham Gritly 63
Editor's Notes
Ellie Whitney and Sharon RadyRolfes; Under standing Nutrition, Twelfth Edition. 2011, 2008 Wadsworth, Cengage Learning
Ellie Whitney and Sharon RadyRolfes; Under standing Nutrition, Twelfth Edition. 2011, 2008 Wadsworth, Cengage Learning
Ellie Whitney and Sharon RadyRolfes; Under standing Nutrition, Twelfth Edition. 2011, 2008 Wadsworth, Cengage Learning
Ellie Whitney and Sharon RadyRolfes; Under standing Nutrition, Twelfth Edition. 2011, 2008 Wadsworth, Cengage Learning
Ref. Ellie Whitney and Sharon RadyRolfes; Under standing Nutrition, Twelfth Edition. 2011, 2008 Wadsworth, Cengage Learning
