basic principles of nutriton

Basic Principles of NutritonProf. Dr. Ahmet AYDINİÜ Cerrahpaşa Tıp Fak.

Çocuk Sağlığı ve Hastalıkları ABDMetabolizma ve Beslenme Bilim Dalı Başkanı

(www.beslenmebulteni.com) (besahmet@yahoo.com)

NUTRITIONAL REQUIREMENTS

• Individual nutritional requirements vary with genetic and metabolic differences.

• For infants and children, the basic goals are satisfactory growth and the avoidance of deficiency states.

• Good nutrition helps to prevent acute and chronic illness and to develop physical and mental potential; it should also provide reserves for stress.

Oral daily water consumption at various ages

Water is essential for existence; a lack of it results in death in a matter of days.

Age Oral daily water consumption (mL/day)

3 days3 days-6 months6-12 months1-4 years10 years18 years

80-100130-160125-145110-13570-8540-50

Energy needs

Energy needs

• Energy needs of children at different ages and under various conditions vary greatly.

• The approximate average expenditures of energy by the child 6-12 yr of age are basal metabolism, 50%; growth, 12%; physical activity, 25%; and fecal loss, about 8%, mainly as unabsorbed fat.

Enteral and Parenteral Energy Consumption of a Newborn

Energy consumption Enteral Parenteral

Basal metabolism

Growth

Physical activity

Fecal loss

Thermoregulation

48

29

15

18

10

41

29

10

-

minimal

Energy requirement at various body weights

Weight Calories

<10 kg

10-20 kg

> 20 kg

100 kcal/kg

1000 + 50 kcal/kg

1500 + 20 kcal/kg

Distribution of calories

Approximately • 9-15% of the calories are derived from

protein, • 45–55% are derived from carbohydrate and • 35–45% are derived from fat.

Each gram of • Ingested protein or carbohydrate provides 4

kcal. • 1 g of long-chain fatty acids provides 9 kcal.

Proteins

Proteins • Protein constitutes about 20% of adult body weight. Its

amino acids are essential nutrients in forming cell protoplasm.

• Twenty amino acids have been identified; eight were found to be essential for children and adults.

• Nonessential amino acids can be synthesized and need not be supplied in the diet.

• New tissue cannot be formed without all of the essential amino acids simultaneously present in the diet.

• The absence or deficiency of only one essential amino acid results in a negative nitrogen balance.

Types of amino acids Essential amino acids Nonessential amino acids

Valine LeucineIsoleucineThreonine LysineTryptophan→ SerotoninPhenylalanine→ Tyrosine MethionineSemi-essential Histidine Arginine

GlycineAlanineCyst(e)in→taurine Tyrosine→Dopamin→ Norepinephrin. Aspartic acidGlutamic acid→ GABASerineAspargineGlutamineProline

Daily protein requirements

Age Daily protein requirements

Age Daily protein requirements

0-6 months

6-12 months

1-6 years

2 g /kg

1.5 g /kg

1.2 g /kg

7-14 years

15-18 years

Adult

1.0 g /kg

1.1 g /kg

0.8 g /kg

Carbohydrates

CarbohydratesThe monosaccharides • Glucose• Fructose• Galactose

The disaccharides• Lactose: glucose +

galactose• Sucrose: glucose +

fructose• Maltose: glucose +

glucose

The polysaccharides • Starch: glucose +

glucose + glucose ……….

• Glycogen: (animal starch)

High glycemic load and insulin resistance

• Highly refined carbohydrates foods with a high glycemic load and /or index overstimulate insulin secretion.

• While hyperinsulinemia causes fat depositon in the fed state, it do not give permission to hydrolysis of fats.

• Insulin resistance leads to common chronic diseases.

Glisemik endeksi yüksek rafine gıdaların açlık ve tokluk metabolizması üzerine olan etkileri

nelerdir?

Glikojen

Glikojen

Protein

Trigliserit

KARACİĞER

YAĞ DOKUSU

KAS

İNSÜLİN (+)

Normal tokluk

Metabo-

lizması

İNSÜLİN (+)

İNSÜLİN (+)

Yavaş emilen şekerler

Glikojen

Protein

Trigliserit

KARACİĞER

YAĞDOKUSU

KAS

GLÜKOZ

Normal açlık metabolizması

(insülin düşük)

Hormona duyarlı lipaz

Glikojen

Glikojen

Protein

Trigliserit

KARACİĞER

YAĞ DOKUSU

KAS

GLÜKOZ

Glisemik endeksi yüksek

gıda alımından

sonraki metabo-

lizma

İnsülin direnci

Glikojen

Glikojen

Protein

Trigliserit

KARACİĞER

YAĞDOKUSU

KAS

GLÜKOZ (-)

(-)

İnsülin direncinde açlık metabolizması

(insülin yüksek)

Hormona duyarlı lipaz

Yüksek insülin

(-)

• Açlık sırasında, normalde enerjimizin %80’ini veren yağların yeteri kadar yıkılmaması kan şekerini düşürür.

• Aşırı şeker alındıktan sonra oluşan bu şeker düşüklüğüne tepkisel (reaktif) hipoglisemi denir.

• Reaktif hipoglisemi değişik nöropsikiatrik bulgulara yol açar. Hipoglisemiye giren kişi semptomlarını hafifletmek için şekerli gıdalara aşırı düşer.

Hipoglisemide görülen semptom ve belirtiler

Merkezi sinir sistemi depresyonu

• Sersemlik• Huzursuzluk• Görme bozukluğu• Garip davranışlar• Başağrısı• Konvülsiyon• Kr. Yorgunluk• Koma

Adrenalin artışı

• Titreme• Terleme• Çarpını• Halsizlik• Depresyon• Kr. Yorgunluk• Panik atak• Ölüm korkusu

Insulin resistance-common chronic diseases I

• Headaches • Multiple sclerosis• Alzheimer disease.• Hyperactivity• Anxiety• Depression• Concentration

difficulties• İnappropriate behavior• Decreased

performance• Drowsiness

• Chromium deficiency• Copper deficiency • Calcium deficiency• Magnesium deficiency

breast cancer• Ovary cancer• Gastric cancer• Prostate cancer• Rectum cancer • Colon cancer • Gall bladder cancer.

Insulin resistance-common chronic diseases II

• Reactive hypoglycemia • Coronary heart disease • Rise in triglycerides• Rise in LDL• Decrease in HDL• Wrinkles • Grey hair • Baldness• Alcoholism • Obesity• Gallstones

• Stomach ulcer • Appendicitis• Fatty liver• Crohn's disease • Ulcerative colitis • Dyspepsia • Constipation • Bacterial infection • Candidiasis• Kidney damage• Kidney stones

Insulin resistance-common chronic diseases III

• Arthritis • Hemorrhoids• Varicose veins• Asthma• Emphysema • Dental caries• Periodontal disease• Osteoporosis• Hypertension• Food allergies • Diabetes

• Cataracts• Atherosclerosis• Free radical formation

Fluid retention • Myopia • Macular degeneration• Gout• Toxemia (pregnancy)• Premensturel

syndrome • Eczema

Lipids

Lipids

Fatty acids

Fosfat Azotlu baz

Triglycerides

Phospholipid

Cholesterol

G l i s e r o l

CH3(CH2)n-COOH

G l i s e r o l

Sfingozin

Glükoz/ Galaktoz

SfingolipiSphingolipid

Esther of Cholesterol

Trans and cis fatty acids

ESSENTIAL FATTY ACIDS

• Essential fatty acids (EFA) are polyunsaturated and grouped into two families, the omega-6 EFAs and the omega-3 EFAs.

• Fats are molecules with a long carbon chain and they have two ends. One end has a methyl group and the other end has a carboxyl group.

• The Greek symbol "omega" is used as it is the last letter in the Greek alphabet. When omega is used in reference to fatty acids it is referring to the methyl end of the fatty acid.

• Thus Omega-3 fatty acids refer to the family of fatty acids in which the first cis double bond closest to the methyl end of the fat is in the 3rd position.

• Omega-6 refers to the family of fatty acids where the first cis double bond closest to the methyl end is in the 6th position.

carboxyl group

methylgroup

• Although we do need both omega-3s and omega-6s it is becoming increasingly clear that an excess of omega-6 fatty acids can have dire consequences.

• Our ancestors evolved on a diet with a ratio of omega-6 to omega-3 of about 1:1.

• A massive change in dietary habits over the last few centuries has changed this ratio to >20:1 and this spells trouble.

Sources and requirements

• The main sources of omega-6 fats are vegetable oils such as corn oil and soy oil that contain a high proportion of linoleic acid.

• Omega-3 fats are found in flaxseed oil, walnut oil, and marine plankton and fatty fish.

• The main component of flaxseed and walnut oils is alpha-linolenic acid while the predominant fatty acids found in fatty fish and fish oils are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

• Humans do not synthesize linoleic or linolenic acid. Both must be supplied in the diet and are, therefore, "essential."

• Linoleic acid is the precursor of arachidonic acid, the prostaglandins and the leukotrienes.

• Essential fatty acids are necessary for growth, skin and hair integrity, regulation of cholesterol metabolism, lipotropic activity, decreased platelet adhesiveness, and reproduction.

Inflamatory mediators

Archidonic acid

Leukotiriene A4

Prostaglandin H2

Leukotiriene B4

Prostaglandin E2 Thrombaxane A2

Lipooxigenase Cyclooxigenase

Tissue phospholipids

Dietary omega-6s

Dietary omega-3’s

(-)(-)

Hydrolase

Fosfolipase A2

Antiinflamatory mediators

Eicosapentoenoic acid

Leukotiriene A5 Prostaglandin H3

Leukotiriene B5 Prostaglandin E3 Thrombaxane A3

Lipooxigenase Cyclooxigenase

Tissue phospholipids

Dietary omega-3s

Dietary omega-6’s

(-)(-)

Hydrolase

Fosfolipase A2

Inflamation

cytokinesTNF-α

interleukine-1(b)interleukine -6

Omega-3DehydroepiandrosteroneVitamin K Vitamin E n-acetyl cysteinNettle seedVitamin D

(-)

II. group prostaglandins, IV. Group leukotiriens (omega-6)

I. and III. group prostaglandins,V. Group leukotiriens (omega-3)

InflamatoryHyperalgesicThromboticMitogenic

AntiinflamatoryAnalgesicAntithromboticAntimitogenic

Diseases related to omega-3 fatty acids deficiency

• Acne • Psychiatric Disorders• AIDS• Allergies• Alzheimer• Angina pectoris• Atherosclerosis• Arthritis• Behavioral disorders• Senility

• Immune deficiency• Heart disease• Cancer• Cystic fibrosis• Learning disorders• Leukemia• Lupus• Malnutrition• Menopause• Schizophrenia

• Diabetes • Dermatitis• Infection• Inflamatory Diseases• Breast Cancer• Breast cyst• Palsy• Vision disorders• Hypertension

• Hyperactivity• Metastasis • Multipl Sclerose• Otoimmunity• Obesity• Chronic fatigue

syndrome• Psoriasis• Reye syndrome

Diseases related to omega-3 fatty acids

deficiency

Saturated fatty acids ButterBeef tallowMargarine

Monounsaturated fatty acids (omega-9)Olive oilHazelnut oil

Poliunsaturated fatty acids (omega-3) Fish / liver oilFlaxseed oil Wall nut oil Canola oil

Poliunsaturated fatty acids (omega-6)Corn Sun flowerSoyaCotton

Fatty acids

Minerals

Minerals• Macrominerals. Minerals in which the requirements are

over 50 mg/day for an adult.

• The principal macrominerals are cations such as calcium, magnesium, potassium, and sodium and their comparable anions are phosphorus, sulfur, and chloride.

• Microminerals: Minerals in which the requirements are below 50 mg/day for an adult.

• Iron, iodine, and cobalt appear in important organic complexes. The trace elements fluorine, copper, zinc, chromium, manganese, selenium, and molybdenum have known metabolic roles; silicon, boron, nickel, aluminum, arsenic, bromine, and strontium are toxic and also present in the diet and in the body.

Vitamins

Water and fat soluble vitamins

B complex vitamins are coenzymes of enzymatic reactions.

B complex vitamins that have roles in energy metabolism

• Vitamin B1 (thiamin)• Vitamin B2 (riboflavin)• Vitamin B3 (Niacin=

nicotinic acid)• Vitamin B5 (pantothenic

acid)• Biotin

Other B complex vitamins• B12 vitamini

(cyanocobalamin)• Folic acid• Vitamin B6 (pyridoxine)

II. Vitamin C (antioxidant)

Fat soluble vitamins• Vitamin A (antioxidant)• Vitamin E (antioxidant)• Vitamin D (calcium

metabolism)• Vitamin K (coagulation)

Water soluble vitamins• Because of their water solubility, excesses of

these vitamins are excreted in urine and so rarely accumulate in toxic concentrations.

• They are heat-labile and can be absorbed in malabsorption syndromes.

Fat soluble vitamins• Because of their fat solubility, excesses of these

vitamins are not excreted in urine and accumulate in toxic concentrations.

• They are heat-resistant and can not be absorbed in malabsorption syndromes.

Flavonoids

Flavonoids• Flavonoids are water soluble polyphenolic molecules

containing 15 carbon atoms. Flavonoids belong to the polyphenol family.

• Flavanoids can be visualized as two benzene rings which are joined together with a short three carbon chain.

• The flavonoids consist of 6 major subgroups: chalcone, flavone, flavonol, flavanone, anthocyanins and isoflavonoids.

• Together with carotenes, flavanoids are also responsible for the coloring of fruits, vegetables and herbs.

Flavonoids• Flavonoids have antioxidant activity. Flavonoids are

becoming very popular because they have many health promoting effects.

• Some of the activities attributed to flavonoids include: anti-allergic, anti-cancer, antioxidant, anti-inflammatory and anti-viral.

• Epidemiological studies have illustrated that heart diseases are inversely related to flavonoid intake.

• The contribution of flavonoids to the total antioxidant activity of components in food can be very high because daily intake can vary between 50 to 500 mg.

Flavonoid Subclass

Dietary Flavonoids Some Common Food Sources

Anthocyanidins Cyanidin, Delphinidin, Malvidin, Pelargonidin, Peonidin, Petunidin

Red, blue, and purple berries; red and purple grapes; red wine

Flavanols Monomers (Catechins):Catechin, Epicatechin, Epigallocatechin Epicatechin gallate, Epigallocatechin gallate

Dimers and Polymers:Theaflavins, Thearubigins, Proanthocyanidins

Catechins: Teas (particularly green and white), chocolate, grapes, berries, apples

Theaflavins, Thearubigins: Teas (particularly black and oolong)

Proanthocyanidins: Chocolate, apples, berries, red grapes, red wine

Flavonoid Subclass

Dietary Flavonoids Some Common Food Sources

Flavanones Hesperetin, Naringenin, Eriodictyol

Citrus fruits and juices, e.g., oranges, grapefruits, lemons

Flavonols Quercetin, Kaempferol, Myricetin, Isorhamnetin

Widely distributed: yellow onions, scallions, kale, broccoli, apples, berries, teas

Flavones Apigenin, Luteolin Parsley, thyme, celery, hot peppers,

Isoflavones Daidzein, Genistein, Glycitein

Soybeans, soy foods, legumes

Probiotics

• There are 100 trillion beneficial bacteria = probiotics (1.5 kg) in your bowels (Bowel flora).

• Bacteria in your bowels outnumber the cells in your body by a factor of 10 to one.

• The health of your body is largely tied into the health of your gut, and it’s hard to have one be healthy if the other is not.

• A large part of the influence of the "bad" bacteria is on the intestinal lining (mucosal barrier) that is over 300 square meters, or about the size of a tennis court.

• Beneficial bacteria in your gut can help to boost the immune system, prevent allergic inflammation and food allergy, clear up eczema in children and heal the intestines from a variety of ailments.

• However, if you are eating as many sugars as the typical Western diet (about 100 kg per year) then you are feeding the "bad" bacteria, which are more likely to cause disease than promote health, rather than promoting the "good" bacteria that help protect you from disease.

• Exposure to chemicals will also contribute to this disruption in your gut microflora, and over time the imbalance will lead to illness.

• The well-known probiotics are fermented foods. yogurt, prickle, kefir

Antioxidants

What are free radicals?

• Free radicals are unstable because they have unpaired electrons in their molecular structure.

• Oxygen, or oxyl, free radicals are especially dangerous.

• These unstable molecules that interact quickly and aggressively with other molecules and destroy them.

Physiological functions of free radicals

Free radicals are involved in many cellular functions and are a normal part of living. For example;

• The mitochondria oxidizes the glucose and fatty acids and in so doing generates free radicals.

• White blood cells also use free radicals to attack and destroy bacteria, viruses and virus-infected cells.

• The detoxifying actions of the liver also require free radicals.

Oxidative Stress

• Although free radicals have useful functions in the body under controlled conditions, they are extremely unstable molecules that can damage cells if left uncontrolled.

• Oxidative stress occurs when the available supply of the body’s antioxidants is insufficient to handle and neutralize free radicals of different types.

• The result is massive cell damage that can result in cellular mutations, tissue breakdown and immune compromise.

• Free radicals destroy cellular membranes; enzymes and DNA.

• They accelerate aging and contribute to the development of many diseases, including cancer and heart disease.

Toxins and free radicals

• Its important to note here that free radicals are also released in the body from the breaking down or detoxification of various chemical compounds.

Fats and free radicals• The major sources of dietary free radicals are chemically-

altered fats from commercial vegetable oils, margarine or vegetable shortening and all oils heated to very high temperatures.

• Replace these harmful fats with natural, cold pressed oils such as olive oil (which can be used for cooking) and small amounts of flax oil or walnut oil (which should never be heated).

• Organic butter and tallow are also excellent choices, especially for cooking.

• Both of these naturally saturated fats are rich in certain fatty acids that have proven activity against bacteria, harmful yeasts, fungi and tumor cells.

Fats and free radicals • Since saturated fats (from animal foods and the tropical oils)

and monounsaturated oils (from olive oil and cold-pressed nut oils) are more chemically stable, they are much less susceptible to oxidation and rancidity than their polyunsaturated cousins, which are mostly found in vegetable oils.

• Trans-fatty acids (TFAs), are produced during hot-processing of polyunsaturated oils.

• As a general rule, then, although the body does require a small amount of naturally occurring polyunsaturated oils in the diet each day, it’s best not to consume too much of them as they are more prone to free radical attack in the body.

• They can destroy the body’s supply of vitamin E, C and other antioxidants cause muscular lesions, brain lesions, and degeneration of blood vessels.

ANTIOXIDANTS

• Fortunately, the body maintains a sophisticated system of chemical and biochemical defenses to control and neutralize free radicals.

• Chemical antioxidants scavenge free radicals, that is, they stabilize the unstable free radicals by giving them the electron they need to “calm down.”

• But they also inhibit free radical formation inside the body

• The antioxidants are usually consumed or used up in this process—they sacrifice themselves.

• The main antioxidants are vitamins A, E and C, beta-carotene, glutathione, bioflavonoids, selenium, zinc, CoQ10 (ubiquinone), and various phyto-chemicals from herbs and foods.

• Lipoic acid, repair enzymes such as catalase, superoxide dismutase (SOD), glutathione peroxidase.

• Melatonin, a hormone produced by the pineal gland, is also a potent antioxidant.

• Cholesterol, produced by the liver, is another major antioxidant, which the body uses to repair damaged blood vessels.

• It is probably for this reason that serum cholesterol levels rise as people age.

• With age comes more free radical activity and in response the body produces more cholesterol to help contain and control the damage.

Glutathione

• Of all the antioxidants, glutathione appears to be pivotal.

• Made up of three amino acids (cysteine, glycine, and glutamic acid), glutathione is part of the antioxidant enzyme glutathione peroxidase and is the major liver antioxidant.

1) Intercellular antioxidants

A) Superoxide dysmutase (SOD).• 2O2+2H+ —SOD→ H2O2+O2 • SOD has two isoenzymes with Cu-Zn and Mn

B) Catalase• 2H2O2 —catalase→ 2H2O+O2

C) Glutathione peroxidase (GSH-Px) • H2O2 + 2 glutathione (GSH) —(GSH-Px)→ 2H2O+ GSSG• GSH-Px has two isoenzymes (selenium dependent and selenium

independent)

D) Cytochrom oxidase

E)Glutathione:The most important intercellular antioxidant . • glutathione (oxidised) —( glutathione reductase)→ glutathione

(reduced)

2) Antioxidants in the membrane

• Vitamin E (alfa-tokoferol): the most powerful lip soluble antioxidant.

• Beta-carotene

• Lipids in membrane: Cholesterol and saturated fats in the membrane e have antioxidant power.

3) Extracellular antioxidants

• Ascorbic acid: The most powerful• Transferrin• Lactoferrin• Haptoglobuline and hemopexine• Ceruloplasmine • Uric acid• Bilirubine• Mucus

Illnesses Associated With Oxidative Stress

• GI Tract: Diabetes, pancreatitis, liver damage, and leaky gut syndrome

Brain and Nervous System: Parkinson’s disease, Alzheimer’s disease, hypertension, multiple sclerosis, Down’s Syndrome

Heart & Blood Vessels: Atherosclerosis, coronary thrombosis.

Lungs: Asthma, emphysema, chronic pulmonary disease.

Eyes: Cataracts, retinopathy, macular degeneration.

Joints: Rheumatoid arthritis

Kidneys: Glomerulonephritis

Skin: “Age spots,” vitiligo, wrinkles.

Body in General: Accelerated aging, cancer, autoimmune diseases, inflammatory states, AIDS and lupus.