Departemen Ilmu & Teknologi PanganFATETA, Institut Pertanian Bogor

THE NUTRIENTS IN OUR BODY

WATER

61 %LIPIDS14%

PROTEIN17%

CARBS1,5 %

MINERALS6 %

VITAMINS< 1 %

as a percentage of body weight

VITAMIN

THIAMIN (B1),

RIBOFLAVIN (B2),

NIACIN (B3),

PIRIDOXIN (B6),

BIOTIN,

PANTHOTENIC ACID

FOLATE (FOLIC ACID),

COBALAMIN (B12),

MINERAL

NUTRIENT: FUNCTION OR RISK

KEAMANAN VITAMIN & MINERAL

Banyak yang berpendapat bahwa hanya vitamin larut lemak ( vitamin A, D, E dan K) yang harus diatur konsumsinya, sedangkan vitamin larut air (vitamin B kompleks danvitamin C) tidak akan membahayakan kesehatan walaupun di konsumsi secaraberlebihan, karena akan dibuang lagi dari dalam tubuh mela lui urine.

Pendapat tersebut ternyata keliru.

Jenis vitamin Asupan tertinggi per hariyang direkomendasikan

Dugaan dosis toksikminimal secara oral

INDEKS KEAMANAN VITAMIN

KEAMANAN VITAMIN

yang direkomendasikanuntuk orang dewasa

minimal secara oralpada orang dewasa

Vitamin A (IU) 5000 25000 - 50000Vitamin D (IU) 400 50000Vitamin E (IU) 30 1200Vitamin C (mg) 60 1000 - 5000Tiamin (mg) 1,5 300Riboflavin (mg) 1,7 1000Niasin (mg) 20 1000Piridoksin (mg) 2,2 2000Folasin (mg) 0,4 400Biotin (mg) 0,3 50As Pantotenat (mg) 10 1000

Sumber: Hathcock (1985).

Fortifikasi mineral pada produk pangan harus mempertimba ngkan efek toksik darimineral tersebut. Untuk mineral makro seperti Ca, P d an Mg, keracunan akibatkelebihan konsumsi tidak terlalu menghawatirkan karena ja rang terjadi . Penambahanmineral makro yang berlebihan akan menimbulkan masalah p ada mutu produk, yaituproduk seperti berpasir (sandiness) atau berkapur (chalk iness). Karena adanyaperubahan mutu tersebut, konsumen dapat dengan mudah mend eteksi danmenghindar dari kemungkinan keracunan.

Untuk mineral mikro seperti Fe, Se dan I, penambahan yan g berkebihan tidak mudahterdeteksi, sehingga berpotensi untuk mengakibatkan ker acunan.

KEAMANAN MINERAL

MineralRDA orang

dewasa(mg)

Dugaan MTDoral orang

dewasa (mg)MSI

Kalsium, Ca 1200 12000 10Fosfor, P 1200 12000 10Magnesium, Mg 400 6000 15Besi, Fe 18 100 5,5Seng, Zn 15 500 33Tembaga, Cu 3 100 33Fluor, F 4 20 5Iodium, I 0,15 2 13Selenium, Se 0,2 1 5

INDEKS KEAMANAN MINERALKeterangan: MTD = minimum toxic dose; MSI = mineral safety index

Sumber: Hathcock (1985).

Nilai MSI yang besar menunjukkanbahwa mineral tersebut toksisitasnyarelatif rendah, dan sebaliknya nilaiMSI yang kecil menunjukkan bahwamineral tersebut toksisitasnya relatiftinggi.

BIOAVAILABILITY

Bioavailability is a post-absorption assessment of how much of a nutrient that has been absorbed becomes functional to the system

Define Bioavailability

The fraction (or percentage) of nutrient absorbed t hat is useful to the body The degree to which an absorbed nutrient is availab le to the system

WITH A FOCUS ON THE

Digestibility of the food source

Solubility (of the mineral) Elements in the food source

that hinder or facilitate absorption

Extrinsic FactorsExtrinsic Factors

Age Health Nutritional state Physiological state Genetic predisposition Gender Developmental stage Species

Intrinsic FactorsIntrinsic Factors

WITH A FOCUS ON THE ORGANISM, BIOAVAILABILITY DEPENDS ON:

BIOAVAILABILITY

RAW FOOD PRODUCT (100%)

PROCESSED FOOD

DIGESTION

Total (proximate analysis)

Chemically available

DIGESTION

ABSORPTION

CELLULAR UPTAKE

FUNCTIONAL NUTRIENT

Biologically available

A nutrient is considered outside

the body until it passes thru the intestinal barrier

ABSORPTIVE ORGANS

ABSORPTION

Stomach : alcohol, weak acids (ex. aspirin), and extremely lipophilicsubstances can be absorbed directly, passively

Jejunum : most things absorbed here.

Terminal ileum : absorption of bile salts and vitamin B12

Colon : some absorption of short chain fatty acids produced by bacterial fermentation of dietary fiber (ex. butyrate)

VITAMIN ABSORPTION

Vitamin Absorption MechanismA, D, E, K & -caroten

From micelle, passive diffusion, then grouped with chylomicron and absorbed via lymphatic vessel

Vitamin C Simple diffusion (slow) or Na +-dependent (rapid)

Thiamin (B 1) Simple diffusion, if concentration in the lumen is low; or Na +-dependent if concentration the lumen is high

Riboflavin (B 2) Passive diffusion

Niacin Na +-dependent or passive diffusion

Pyridoxine Passive diffusion

Folacin Na +-dependentCobalamin(B12)

With the help of gastric intrinsic factor

The fat-soluble vitamins such as A, D, E and K, need to dissolve in fat before they can make it into the body.

The process requires fat-digesting bile acids that come from the liver and live in the small intestine. When the bile acids break down the fat, the vitamins are dissolved in.

The vitamins move with the fat through the intestinal wall, into the body, and finally end up in the liver and in body fat, where theyre stored until theyre needed.

MINERAL ABSORPTION

generallly it needs a carrier (protein), Na-pump,and/or ATP:

Ca : Ca-binding protein, Na-pump, ATPZn : protein-carrier (Metallothionien)Fe : protein-carrier, ATPSe : protein-carrier (Selenometallothionien)Mg : passive diffusion

absorption of divalent ions (Ca2+, Fe2+) are slower than monovalent ions (Na+, K+)

Ca is absorbed 50 X more slowly than Na, but is

Ca is absorbed 50 X more slowly than Na, but is absorbed faster than Fe, Zn & Mn

FACTORS THAT INFLUENCE OR REGULATE MINERAL ABSORPTION:

(1) Intrinsic, homeostatic regulation(2) Health of individual(3) Dietary factors (phytate, dietary fiber, tannins &

oxalate)(4) Diseases that alter the intestinal transit time

(gastric surgery), the intraluminal pH (pancreatic insufficiency) or mucosal integrity (celiac sprue)

Garam KalsiumKelarutan Ca dlm

air pada 25 oC(g/L)

RasaKadar

Kalsium(%)

Ca-karbonat tidak larut sabun, lemon 40

Karakteristik penting sumber kalsium untuk fortifikasi

KELARUTAN MINERAL vs BIOAVAILABILITAS

Keefektifan kalsium sebagai fortifikan tergantung pada bi oavailabilitasnya. Secararata-rata hanya sekitar 10 - 30 % kalsium yang dapat dis erap oleh usus orang dewasasehat. Umumnya bioavailablitas garam kalsium organik lebih tingg i dibandingkandengan garam kalsium anorganik.

Ca-karbonat tidak larut sabun, lemon 40Ca-fosfat tidak larut berpasir, tidak berasa 17 - 38Tri-Ca-sitrat (4H 2O) 0,9 netral 21Ca-laktat (5H 2O) 9,3 tidak berasa 13Ca-laktat-glukonat 45 - 50 netral 10 - 13Ca-glukonat 3,5 ringan, netral 9

Bioavailabilitas kalsium dari tri-Ca-sitrat, Ca-laktat , Ca-laktat-glukonat dan Ca-glukonat tidak berbeda, walaupun kelarutannya dalam air tidak sama

(Flynn A dan K Cashman, 1999)

INHIBITOR PENYERAPAN MINERALDi dalam bahan pangan seringkali terdapat senyawa yang da patmenghambat penyerapan (bioavailabilitas) beberapa maca m mineral

Serat Pangan , secara fisik dapat menghambat penyerapan mineral

Oksalat , terdapat dalam sayur-sayuran, dapatmengikat kalsium (terutama), zat besidan mineral lain (?). sehingga tidakdapat diserap oleh usus

Tanin (senyawa polifenol) dapat mengikatmineral, contohnya: Fe + Tanin Fero tanat

Asam fitat (Fitat), bentuk fosfor dalamtanaman, sehingga P tidak dapatdiserap usus; asam fitat dapatmengikat mineral valensi dua(Ca, Mg, Fe, Zn, Cu dan Mn), sehingga tidak dapat diserapoleh usus

Source: Schlemmer U, et al. Phytate in foods and

Source: Schlemmer U, et al. Phytate in foods and significance for humans: Food sources, intake, processing, bioaailability, protective role and ana lysis. Mol Nutr Food Res 2009;53:S330-S375.

Source: Schlemmer U, et al. Phytate in foods and significance for humans: Food sources, intake,

significance for humans: Food sources, intake, processing, bioaailability, protective role and ana lysis. Mol Nutr Food Res 2009;53:S330-S375.

These foods are high in oxalate (greater than 10 mg per serving):

Beans in tomato sauce, Beer, Beets, Blac kberries, Black and red raspberries, Blueberries, Celery, Chard, Chocolate, Cocoa , Coffee powder (Nescafe), Collards, Concord grapes, Crackers made from soy flour , Currants, Dandelion greens, Eggplant. Escarole, Fruit cake, Fruit salad (canned), Green bell pepper, Grits (white corn), Juices containing berries, Kale, Leeks, Lemon and lime peel, Nuts (especially peanuts and pecans), Okra, Ovaltine, Parsley, Pokew eed, Rhubarb, Rutabagas, Spinach, Strawberries, Summer squash, Sweet potatoes , Tea, Tofu , Tomato soup, Wheat germ

These foods are moderately high in oxalate (210 mg per serving):

OXALATE CONTENT OF FOODSSource: Leonardo M. Canessa, 2015. Oxalate Content of Foods. The Childrens Medical Center, Abiodun, Omoloja, M.D.

Apple, Apricots, Asparagus, Bottled beer (12 oz [360 ml] limit/day), Broccoli, Carrot s, Chicken noodle soup (dried), Coffee (8 oz [240 ml]), Cola beverage (12 oz [ 360 ml] limit per day), Corn, Cornbread, Cucumber, Lettuc e, Lima beans, Marmalade, Oranges, Orange juice (4 oz [120 ml]), Parsnips, Pea ches, Pears, Peas (canned), Pepper (greate r than 1 tsp [2 grams] per day), Pineapple, Plu ms, Prunes, Sardines, Soy products (most), Sponge cake, Tomatoes, Tomato juice (4 oz [12 0 ml]), Turnip, Watercress

These foods are low in oxalate (02 mg per serving); eat as desired:

Apple juice, Avocado, Bacon, Bananas, Beef (lean), Bing cherries, Brussels sprouts, Cabbage, Cauliflower, Cheese, Eggs, G rapefruit, Green grapes, Jellies, Lamb (le an), Lemonade or limeaid (without peel), Melons, M ilk, Mushrooms, Pork (lean), Poultry, Preserves, Nectarines, Noodles, Oatmeal, Oils, Onions, Peas (fresh), Plums, Radishes, Rice, Salad dressing, Seafood, Spaghetti, White bread, Wine, Yogurt

FAKTOR YANG MENINGKATKAN PENYERAPAN KALSIUM

- Vitamin D dan vitamin K- Asam lambung (HCl) yang cukup- Jumlah lemak rendah (jumlah lemak

tinggi menurunkanketersediaan kalsium)

- Gerak fisik , serta

- Gerak fisik , serta- Hormon, termasuk hormon paratiroid

dan estrogen

Fungsi hormon Paratorid: menstimulir penyerapan Ca dlm ususdan re-absorpsi Ca dlm ginjal

Fungsi hormon Estrogen: mengurangi bone resorption dan meningkatkanbone formation

Infant Formula (Codex Stan 72-1981)

Vitamin D Calcium Phosphorus Ratio Ca:P

Min Max Min Max Min Max Min Max

mmmmg/100 kcal mg/100 kcal mg/100 kcal

1 2.5 50 - 25 - 1:1 2:1

RASIO KALSIUM : FOSFOR

It was recommended that the minimum calcium content in infant formulae should be maintained at 50 mg/100 kcal, and the maximum level should be 140 mg/100 kcal.

The ratio of calcium to available

Follow up Formula (Codex Stan 156-1987)

Vitamin D Calcium Phosphorus Ratio Ca:P

Min Max Min Max Min Max Min Max

mmmmg/100 kcal mg/100 kcal mg/100 kcal

1 3 90 - 60 - 1.2 2.0

The ratio of calcium to available phosphorus (based on measured bioavailability, or calculated as 80% of total phosphorus in cows milk protein based formulae) should be not less than 1.0 nor greater than 2.0.

This recommendation also applies to follow-on formulae.

(The Scientific Committee on Food, European Commission, 2003)

ZAT BESI

Zat besi (Fe) antara lain diperlukan untuk pembentu kan hemoglobin (pigmen sel darah merah). Defisiensi zat besi dapat mengakibat kan timbulnya anemia

Chinese studies with NaFeEDTA fortified soy sauce (Mannar & Boy 2002)

Zat besi yang dapat digunakan untuk fortifikasi[Guidelines PAHO (2002)]:

- ferrous sulfate, encapsulated ferrous sulfate- ferrous fumarate, encapsulated fumarate- electrolytic iron - NaFeEDTA

Other elemental iron compounds (H-reduced, CO-reduced, atomized, carbonyl) are not recommended at the present time

NON-HEME IRON ABSORPTION

(Monsen & Cook, 1979)

ZAT BESI & VITAMIN C

Enhancing effect of ascorbic acid on non-heme iron a bsorption

it is exerted by both its reducing capacity, thereb y keeping iron in the more easily absorbed ferrous (+II) form; and its chelating prop erties, keeping iron in a soluble, absorbable form

Propose Ascorbic Acid to Iron Ratio

It is convenient to base quantitative recommendatio ns for ascorbic acid on the molar ratio of ascorbic acid to iron, which should be between 2:1 and 4:1.

It indicates that absorption values of 10% can be e xpected for cows milk if ascorbic acid and ferrous sulfate are added in an ascorbic acid to iron molar ratio of 2:1.

A molar ratio of 4:1 would be required if more inhib itory foods such as soybeanswith a native phytate content are added

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IRON ABSORPTION & METABOLISM

PENGARUH PROTEIN THD PENYERAPAN ZAT BESI

Egg albumen strongly inhibited absorption of non-he me iron

(Monsen & Cook, 1979)

PENGARUH PROTEIN THD PENYERAPAN ZAT BESI

Other non-cellular animal proteins (milk, cheese, e gg) are also inhibitory to the absorption of non-heme ir on

(Cook & Monsen, 1976)

PENGARUH PROTEIN THD PENYERAPAN ZAT BESI

Cellular animal proteins appear to enhance the abso rption of non-heme iron

(Cooke & Monsen, 1976)

PENGARUH PROTEIN THD PENYERAPAN ZAT BESI

The enhancing effect of cellular animal protein to the absorption of non-heme iron is dose-related

(Cook & Monsen, 1975; Bjorn-Rasmussen & Hallberg, 1 979)

PROTEIN KEDELAI & PENYERAPAN ZAT BESI

Soy protein has an exceptionally inhibitory effect:

- Non-heme iron was absorbed at only 20 % of the refe rence level,

when soy protein was substituted for egg albumen

- The addition of 100 mg ascorbic acid to the soy pro tein meals

- The addition of 100 mg ascorbic acid to the soy pro tein meals

increased absorption of non-heme iron the soy inhibition

seemed to be modulated more by ascorbic acid than b y the

addition of meat to the isolated soy protein meals

iron in soybean flour is bound to phytoferritin poor

absorption in human

IRON-ZINC (Fe-Zn)

- Zinc suppresses iron efficacy for growth of school boys

- Excessive oral iron aggravates zinc deficiency

- High iron contents of infant formulas depresses pl asma zinc levels

- High levels of prenatal iron supplementation were associated with lower maternal zinc levels in pregnancy

INTERACTION OF IRON AND OTHER MINERALS

IRON-CHROMIUM (Fe-Cr)

- It seems that iron would compete with chromium for transport in t he circulation

IRON-MANGANESE (Fe-Mn)

- Inhibition of intestinal manganese absorption in th e presence of excessive dietary or intra-luminal iron

REACTIVE OXYGEN SPECIES

PEMBENTUKAN RADIKAL HIDROKSIL (OH*) OLEH ION Fe

Fenton Reaction :A mixture of hydrogen peroxide and an iron(II) salt s causes

the formation of hydroxyl radicalFe2+ + H2O2 interm complex Fe3+ + OH- + HO

Fe3+ + H2O2 interm complex Fe2+ + O2 - + 2H+

Haber-Weiss Reaction:Fe2+ + H2O2 Fe3+ + OH- + HO

Fe3+ + O2 - Fe2+ + O2

Net : O 2 - + H2O2 O2 + HO + OH-

HYDROXYL RADICAL (HO): Highly reactive oxygen

radicals. Formation of hydroxyl radicals in biological systems Ionizing radiation Reaction of metal ions with hydrogen peroxide

(Fenton reaction) Formation of hydroxyl radical from ozone (O 3)

NEGATIVE EFFECTS OF FREE RADICALS

Some biomolecules that are targets of free radical d amage include DNA/RNA, proteins, and lipids. The consequences of these will include:

(a) DNA/RNA, whereby there may be: scission of deoxyribose ring, base damage, strand br eakage

leading to mutations, translational errors, and inh ibition of protein synthesis.

(b) in proteins there may be: oxidation, aggregation, fragmentation, and modif ication of

oxidation, aggregation, fragmentation, and modif ication of thiol groups . Which may lead to: modified enzyme a ctivity, modified ion transport, increased calcium influx, and protein degradation.

(c) in lipids , there may be: loss of saturation,

formation of reactive metabolites leading to altered membrane fluidity and permeability, effects on membrane bound enzymes, and lipid peroxidativemembrane damage .

OXIDATIVE PROTEIN DEGRADATIONS

Modifications ofamino acid chain

Modifications ofprosthetic group

of enzymes

Protein aggregationProtein fragmentation

Modified enzymes activity

ZINC SULFAT paling banyak digunakan karenaharganya relatif murah.Kekurangan: (1) tidak mudah diserap oleh usus,(2) dapat menimbulkan gangguan pada perut, (3) cenderung menyebabkan teroksidasinya

lipida (lemak) yang terkandung dalam bahanpangan dan dapat menimbulkan ketengikan.

Senyawa Zn Senyawa Zn lainZn- sulfat Zn-pikolinatZn-klorida Zn-sitratZn-glukonat Zn asetatZn-oksida Zn-gliseratZn stearat Zn-monometionin

SENYAWA ZINC UNTUK FORTIFIKASI

ZINC OKSIDA, meskipun tidak mudah diserap oleh usus, tet api banyak digunakankarena ukuran partikelnya kecil dan tidak mempengaruhi bai k teksturmaupun citarasa serta umur simpan bahan pangan.

ZINC GLUKONAT dan ZINC MONOMETIONIN dilaporkan lebih m udah diserap olehusus dibandingkan dengan zinc sulfat dan zinc oksida.

ZINC SITRAT lebih mudah diserap oleh usus dibandingkan de ngan zinc sulfat danzinc oksida.

ZINC PIKOLINAT dilaporkan lebih mudah diserap oleh usus d ibandingkan dengan zinc sitrat dan zinc glukonat.

KelompokUmur

Zinc(mg/hari)

KelompokUmur

Zinc(mg/hari)

Anak Wanita0 - 6 bln 1,3 10 - 12 thn 12,67 - 11 bln 7,5 13 - 15 thn 15,41 - 3 thn 8,2 16 - 18 thn 14,04 - 6 thn 9,7 19 - 29 thn 9,37 - 9 thn 11,2 30 - 49 thn 9,8Pria 50 - 64 th 9,8

AKG zinc untuk berbagai kelompok umurdan ienis kelamin

DOSIS FORTIFIKASI ZINC

Umumnya fortifikasi harus dapatmemenuhi sekitar sepertiga sampaisetengah AKG.

Dosis ini penting untuk diperhatikanmengingat konsumsi zinc yang berlebihan dapat menyebabkangangguan terhadap kesehatan.

Konsumsi zinc dosis tinggi dapatmenghambat pembentukan sel darah

Pria 50 - 64 th 9,810 - 12 thn 14,0 > 65 thn 9,813 - 15 thn 17,4 Hamil (+ an)16 - 18 thn 17,0 Trimest 1 1,719 - 29 thn 12,1 Trimest 2 4,230 - 49 thn 13,4 Trimest 3 9,050 - 64 th 13,4 Menyusui (+ an)> 65 thn 13,4 6 bln pertama 4,6

6 bln kedua 4,6

menghambat pembentukan sel darahdan menekan sistem imun.

Feeding zinc levels out of proportion to copper has important biological consequences copper absorption is diminished when dietary levels of zinc are high

Telah dibuktikan bahwa konsumsi zinc dalam jumlah tinggi ( > 50 mg per hari) dalamwaktu mingguan dapat mempengaruhi bioavailabilitas Cu.

Sebaiknya fortifikasi dilakukan dengan rasio Zn : Cu = 2 : 1.

ZINC & COPPER ABSORPTION

FORTIFIKASI ASAM FOLAT

Pemberian suplemen folat dianjurkan untuk wanita hamil dal am rangka mencegahterjadinya kelainan pada tabung syaraf (neural tube defe cts, NTD) pada bayiyang dikandungnya. Risiko timbulnya NTD ditemukan men urun di banyaknegara sejak asam folat digunakan untuk fortifikasi tepung terigu danserealia lain.

The FDA ruled that starting January 1, 1998, all cereal and grain products labeled enriched must be fortified with folic acid.

140 mcg Folic Acid per 100 grams of flour.

Jumlah fortifikan asam folat di Amerika Serikat ditetapkan sebanyak 140 mcg/100 g

Jumlah fortifikan asam folat di Amerika Serikat ditetapkan sebanyak 140 mcg/100 g produk serealia, dan diharapkan dapat meningkatkan asupa n asam folatsekitar 100 mikrogram per orang per hari.

Di Indonesia, fortifikasi tepung terigu dengan asam fola t, ditetapkan sebesar 2 ppm(2 mg/kg = 0,2 mg/100 g = 200 mcg/100 g).

Konsekuensi biokimia dan fisiologis dengan adanya asam fol at bebas dalam jumlahbanyak di dalam darah belum diketahui dengan pasti, namun b eberapapeneliti menyebutkan dapat meningkatkan angka insidensi kanker kolorektalserta kerusakan pada sistem syaraf pusat terutama pada mere ka yang telahberusia lanjut.

p-Amino-benzoic

acid

PteridineFolate = Natural FormFolic Acid = Synthetic Form

Folate is the natural (complex) form found in foods such as dark-green leafy vegetables, broccoli, asparagus, lentils, beans, peanuts, strawberries, kiwi, orange juice, liver.

Folic acid is the synthetic (simple)

FOLATE & FOLIC ACID

FOLIC ACID (Pteroyl-monoglutamic acid)

L-Glutamicacid

acidFolic acid is the synthetic (simple)form of folate. Used in nutritional supplements and food fortification.

The structural difference between folic acid and food folate accounts for differences in bio-availability, with folic acid being more readily absorbed.

WHAT DOES FOLIC ACID DO?

Although the underlying biologic mechanism is unknown, researchers have found strong evidence that the B-vitamin, folic acid, can prevent 50-70% of neural tube defects (NTD)

Neural Tube Defects (NTDs) are birth defects of the brain and the spinal cord . They occur when the neural tube , which later becomes the brain and the spine, fails to close properly. This happens very early in pregnancy, between the 17th and the 28th day after conception.

After the egg and the sperm unite, cells divide and multiply to form an elongated structure as seen in day 22.

A zippering effect closes the groove or the tube beginning in the center and going both up and down as seen in day 23.

WHAT ARE NEURAL TUBE DEFECTS?

The damage that occurs may lead to muscle weakness, paralysis, and loss of bowel and bladder control.

ENCEPHALOCELE SPINA BIFIDA

Neural tube defect (NTD) adalah suatu kelainanbawaan (kongenital) akibat terjadinya kegagalanpenutupan lempeng saraf (neural plate) pada padajanin, yang terjadi pada minggu ketiga hinggakeempat masa kehamilan.

WHAT ELSE DOES FOLIC ACID DO?

Folic acid and other B vitamins are needed to produ ce red blood cells.

Folic acid is also necessary for the production and maintenance of DNA and RNA, the building blocks of cells.

Due to its capacity to lower blood homocysteine leve l, it may reduce the risk of heart disease and stroke.

Homosistein diketahui merupakan faktor independen yang berkontribusi padatimbulnya penyakit kardiovaskuler, terutama bila kadarn ya dalam darah mencapailebih dari 10 mikromol per liter (level yang diinginka n kurang dari 9 - 10 mikromol per liter). Diasumsikan bahwa peningkatan kadar homosistei n dalam plasma darahdisebabkan karena defisiensi folat (serta vitamin B 12 dan vitamin B 6).

Mekanisme patofisiologi mengapa homosistein dapat mening katkan risiko timbulnyapenyakit kardiovaskuler adalah terjadinya kerusakan pada sel-sel endotelial vaskuleroleh ROS (reactive oxygen species) yang terbentuk sel ama oto-oksidasi homosisteinplasma.

HOMOSISTEIN

plasma.

FOLATE & ZINC INTERACTION

Folate (pteroyl-monoglutamic acid) supplements were r eported to exert negative effect on zinc absorption

It was hypothesized that this form of folate would ch elate zinc and make it less available for absorption

Effect of folate supplementation on fecal and

Effect of folate supplementation on fecal and urinary losses of zinc

Zinc (mg/day) p

Low folate Supplement

Feces 5.83 + 1.20 7.30 + 1.21 < 0.008

Urine 0.45 + 0.11 0.28 + 0.10 0.001