FSHN 3620 • Exam 1 - Study Guide Questions

Principles of the Science of Nutrition

1. Food is a basic need of humans.

2. Foods provide energy (calories), nutrients, and other substances needed for growth and health.

3. Health problems related to nutrition originate within cells.

4. Poor nutrition can result from both inadequate and excessive levels of nutrient intake.

5. Humans have adaptive mechanisms for managing fluctuations in food intake

6. Malnutrition can result from poor diets and from disease states, genetic factors, or combinations of these causes. 

7. Some groups of people are at higher risk of becoming inadequately nourished than others

8. Poor nutrition can influence the development of certain chronic diseases. 

9. Adequacy, variety, and balance are key characteristics of healthy dietary patterns.

10. There are no “good” or “bad” foods.

Community-level assessment

•  can be estimated using existing vital stat data, seeking opinions of target group members & local health experts and making observations.

  • SNAP

  • Food banks & soup kitchens

  • WIC

Individual-level assessment

•  Data from all 4 are needed to describe one’s nutritional status.

  • Clinical/physical assessment

  • Dietary assessment

  • Anthropometric assessment

  • Biochemical assessment

Clinical/physical assessment

visual inspection of a person by a trained RDN or other qualified professional to note physical features that may suggest nutrition related problems.

Dietary Assessment

24 hr Recall

List of foods & beverages consumed in last 24 hrs

Dietary Assessment

Dietary History

interview by trained professional, 1 ½ hrs long; includes 24 hr recall, FFQ; more complete accurate data

Dietary Assessment

FFQ

Estimate food & nutrient intake of groups of people

Dietary Assessment

USDAs Multiple-Pass method

1. Quick list

2. Forgotten foods

3. Time & occasion

4. Detail cycle

5. Final probe

Dietary Assessment

Healthy Eating Index

assess a person's reported dietary intake based on 10 dietary components that cover intake of the USDA’s basic food groups.

Dietary Assessment

Anthropometric Assessment

measures of body size (H,W, % body fat, bone density, & head/waist circumferences)

Dietary Assessment

Biochemical Assessment

nutrient & enzyme levels, gene characteristics, & other biological markers.

Dietary Assessment

National Nutritional Health

nutrition surveillance & nutrition monitoring

Human chorionic gonadotropin (hCG)

• Indicates pregnancy on a pregnancy test

• Should approximately double every 2 days in the first weeks of pregnancy

  • Variance of this may indicate a problem

functions:

• Initiates production of estrogen & progesterone

• Stimulates growth of the endometrium

• Likely contributes to nausea & vomiting symptoms

4 Major Hormones in Female Reproductive System

• Follicle-stimulating hormone (FSH): Stimulates growth of ova

• Luteinizing hormone (LH): Stimulates secretion of progesterone

• Estrogen

• Progesterone

Describe the Menstrual Cycle

• Follicular Phase

  • Day 1-7: Period

  • Day 7-14: Proliferative Phase → Estrogen surges

• Day 14: Ovulation → LH surges, FSH lesser surge

• Luteal Phase

  • Day 14-28:  Secretory Phase → Progesterone & Estrogen surge

Purpose of menstrual cycle

• To prepare ovum for fertilization by sperm + uterus for implantation of a fertilized egg

• Results from complex interactions among hormones secreted by the hypothalamus, pituitary gland, & ovaries

Luteinizing hormone (LH)

produced by the pituitary gland that stimulates ovulation, the development of the corpus luteum (which secretes progesterone), and the production of testosterone in men.

Estrogen

• Enlargement of uterus

• Enlargement of breast tissue

• Increases blood circulation

• Increases protein synthesis

• Increases lipid formation and storage

Progesterone

• Smooths uterine and GI muscles

• Lowers esophageal sphincter tone, causing increased heartburn

• Can lead to constipation

• Proper functioning of placenta

• Promotes growth of endometrium

• Promotes lipid accumulation

• Loosens joints and ligaments

• Prepare breasts for lactation

• Decreases immune system function

• Anti-inflammatory effect

Follicle-stimulating hormone (FSH)

produced by the pituitary gland that stimulates ovarian follicle growth and maturation, estrogen secretion, and endometrial changes characteristic of the first portion of the menstrual cycle in women. It stimulates sperm production in men.

Gonadotropin-releasing hormone (GnRH)

produced in the hypothalamus and is responsible for the release of FSH & LH by the pituitary gland.

• Energy deficits can suppress this

Importance of preconception nutrition

• Optimized nutrition →  optimal fertility →  successful pregnancy

• Folate (natural) /Folic Acid (supplement) – 400 mcg/day

  • Prevents NTDs & SGA newborns

  • Prevents spina bifida & anencephaly

• Iron

  • Fertility

  • Brain dev.

  • Properly timed delivery

• Iodine – thyroid hormone function

• Zinc

  • Important in males & females

  • Sperm maturation & testosterone syn.

  • Egg quality & maturation

  • Fertilization

  • DNA syn.

• Antioxidants – Protect eggs & sperm from oxidative stress

  • Limit or omit alcohol

Infertility

 fail to conceive within 12 months of attempting pregnancy.

Infertility risk factors for men & women

• Endocrine/hormonal abnormalities

• Severe stress

• STDs: pelvic inflammatory disease (PID)

• Endometriosis: abnormal growth of endometrium in other places.

• Toxic substances & environmental contaminants (heavy metals)

  • caffeine, alcohol, nicotine, etc.

• Underweight & overweight

• Old age >40

Potential health problems of women with Celiac

• Amenorrhea

• Increased rate of miscarriage

• Fetal growth restriction

• Low birth weight deliveries

• Short lactation duration

Potential health problems of men with Celiac

• Alterations in androgens

• Delayed sexual maturation

• Hypogonadism: deficiency of sex hormones, poor development & functioning of reproductive system.

How does PCOS affect fertility?

 Infertility is primarily due to the absence of ovulation

Polycystic ovaries: presence of a high number of immature eggs surrounded by fluid-filled sacs in the ovary.

How does Celiac disease impact fertility?

• Somewhat high to substantially high rates of infertility

• Malabsorption-induced deficiencies in nutrients like zinc, folate, & iron

• Direct inflammation on intestines & other tissues

How does diabetes impact fertility?

• Tetrogenic

• Congenital abnormalities 

• Malformations of pelvis, CNS, and heart

• Increased risk of miscarriage

Physiological changes during the anabolic phase (first half) of pregnancy

1. Approximately 10% of fetal growth

2. Mother’s body is building capacity to deliver all the blood, oxygen, & nutrients the baby will need during the second half of pregnancy

   1. Increased appetite

   2. Increased anabolic hormones

   3. Decreased exercise tolerance

Physiological changes during the catabolic phase (second half) of pregnancy

1. Approximately 90% of fetal growth

2. Support fetal development by mobilization of stored nutrients to the developing fetus

   1. Increased catabolic hormones

   2. Increased exercise tolerance

   3. Increased req. of fetus & preparation for birth & lactation

Cardiovascular system changes in pregnancy

• Increased heart rate

• Cardiomegaly: increased heart size, move up to the left.

• Decreased BP (middle of pregnancy)

• Cardiac output increases 30 - 50%

Hematological system changes in pregnancy

• Plasma volume increases by 50%

• Increase in oxygen carrying capacity

• Increase in clotting factors

Respiratory system changes in pregnacy

• 40% increase in ventilation (tidal volume)

• Increased oxygen consumption

Renal system changes in pregnancy

• Kidneys grow in size

• Increase in sodium retention

• Increased risk of UTI

Gastrointestinal system changes in pregnancy

• Progesterone decreases esophageal sphincter tone and GI track muscle tone

• Slower GI transit time

• Nausea (70%), vomiting (40%)

• Heartburn

• Constipation

Immune system changes in pregnancy

• Suppressed immunity because progesterone

• Increased risk of infections

Fetal growth stages, starting from conception 

Day 1:

Conception – 1 zygote exists

Fetal growth stages, starting from conception

Day 2-3

8 cells formed (morula) & enter uterine cavity

Fetal growth stages, starting from conception

Day 6-8

Morula becomes fluid filled, now a blastocyst (250 cells)

Fetal growth stages, starting from conception

Day 10

Embryo implants into uterine wall where glycogen accumulates

Fetal growth stages, starting from conception

Day 12

Embryo (1000s of cells) differentiation, uterine placental circulation being formed

Fetal growth stages, starting from conception

Week 4

¼ in long, rudimentary head, trunk, arms, heart “practices” beating, spinal cord & 2 major brain lobes present.

Fetal growth stages, starting from conception

Week 5

Rudimentary kidney, liver, circulatory sys, eyes, ears, mouth, hands, arms, and GI tract; heart beats 65x/min (circulating own blood)

Fetal growth stages, starting from conception

Week 7

 ½ in long, weighs 2-3 g, brain sends impulses, GI tract produces enzymes, kidney eliminates some waste products, liver produces RBCs, muscles work

Fetal growth stages, starting from conception

Week 9

Embryo is a fetus

Fetal growth stages, starting from conception

Month 3

Weighs 1 oz, primitive egg & sperm cells developed, hard palate fuses, breathes in amniotic fluid

Fetal growth stages, starting from conception

Month 4

Weighs 6 oz, placenta diameter is 3 in

Fetal growth stages, starting from conception

Month 5

Weighs 1 lb, 11 in long, skeleton begins to calcify, hair grows

Fetal growth stages, starting from conception

Month 6

14 in long, fat accumulation begins, permanent teeth buds form, lungs, GI tract & kidneys formed (not fully functional)

Fetal growth stages, starting from conception

Month 7

Gains ½ – 1 oz / day

Fetal growth stages, starting from conception

Month 8-9

Gains 1 oz / day, stores fat, glycogen, iron, folate, vit B₆ & ₁₂ , riboflavin, calcium, magnesium, vit A, E & D; functions of organs continue; growth declines near term; placenta weighs 500-650 g (1-1 ½ lb) at term

Placenta functions

• Exchanges O₂ and CO₂ (works as lung)

  • Two separate circulatory systems

  • Mom’s blood and baby’s blood don’t mix

• Transfers nutrients (works as digestive system)

• Removes wastes (works as kidney)

• Immune barrier; double lining of cells

• Secretes hCG, estrogen, progesterone, hCS

• Cannot block all harmful substances (alcohol passes)

• Develops gradually during the first 3 months of pregnancy

• Large spongy disc

• You should NOT eat the placenta

CHO metabolism in pregnancy — first half

estrogen- & progesterone-stimulated increases in insulin production & conversion of glucose to glycogen and fat

CHO metabolism in pregnancy — second half

• rising levels of hCS & prolactin from mother’s pituitary gland to inhibit glucose → glycogen & fat

• Insulin resistance builds up, increasing reliance on fats for energy

• Increased liver production

CHO metabolism in pregnancy — third trimester

• fasting maternal glucose levels decline bc of increased utilization of glucose by fetus

• Post-meal blood glucose conc. are elevated and remain so (longer than pre-pregnancy)

Fat metabolism in pregnancy — first half

accumulation of maternal fat stores

Fat metabolism in pregnancy — second half

enhanced fat mobilization

Preeclampsia

typically diagnosed after the 20th week of pregnancy. It is characterized by BP readings that exceed 140/90 mm Hg documented on two occasions by BP measurements made at least four hours apart.

Preeclampsia symptoms

headache, blurred vision, abdominal pain, low platelet count, abnormal liver enzyme values

Preeclampsia characteristics

• Oxidative stress, inadequate antioxidant defenses, inflammation, & endothelial dysfunction

• Platelet aggression & blood coagulation due to deficits of prostacyclin relative to thromboxane

• Blood vessel spasms & constriction, restricted blood flow

• Increased blood pressure

• Insulin resistance

• Adverse maternal immune system responses to the placenta 

• Elevated blood TGs, free FAs & chol

Pregnancy exercise recommendations

• Frequent rest periods

• Don’t hold breath

• Don’t exercise until exhaustion

• Avoid exercise in heat & humidity

• No twisting & bouncing

• Non-weight bearing → cycling, swimming, yoga

• Drink plenty of liquids

Weight gain (know this table)

Protein needs in pregnancy

Increased protein & N – 2 lbs pure protein accumulated

Micronutrient needs in pregnancy

• Vit D → 15 mcg

• Vit A → <10,000 IU

• Iron → 27 mg/day

• Folate → 300 mcg

• Increased sodium & calcium → bone formation

• Magnesium → 350 mg

• Iodine → 220 mcg

• Calcium → 1,000-1,300 mg

Birth defects caused by nutritional issues

• Neural tube defects – Folate deficiency

• Fetal malformations – Vitamin A deficiency & toxicity

• PKU – genetic factor

• Congenital abnormalities & hypothyroidism – Iodine deficiency

• Abnormal bone development → Vitamin D deficiency

High Risk Pregnancies

Age: 18> and >40

• Low birthweight

• Perinatal death

• C-section

• Cephalopelvic disproportion: head to large for birth canal

• Preeclampsia

• Iron-deficiency anemia

• Delayed, reduced educational achievement

• Poverty

• Poor diet quality

High Risk Pregnancies

Multifetal (mother’s risks)

• Preeclampsia

• Iron-deficiency anemia

• Gestational diabetes

• Hyperemesis gravidarum

• Placenta previa

• Kidney disease

• Fetal loss

• Preterm delivery

• C-section

High Risk Pregnancies

Multifetal (newborn’s risks)

• Neonatal death

• Congenital abnormalities

• Respiratory distress syndrome

• Intraventricular hemorrhage

• Cerebral palsy

• Low birthweight

High Risk Pregnancies

Obesity

• Gestational diabetes

• Preeclampsia

• PP hemorrhage

• PP depression

• Preterm delivery

High Risk Pregnancies

Diabetes (mother’s risks)

• Caesarean delivery

• Shoulder dystocia

• Increased risk for preeclampsia

• Increased risk of type 2 diabetes, hypertension, & obesity later in life

• Increased risk for gestational diabetes in a subsequent pregnancy

• Hypoglycemia

• Maternal death

High Risk Pregnancies

Diabetes (newborn’s risks)

• Stillbirth

• Spontaneous abortion

• Congenital anomalies

• Macrosomia (10lb)

• Neonatal death

• Neonatal hypoglycemia, hypocalcemia, & hyperbilirubinemia

• Increased risk of insulin resistance, type 2 diabetes, high BP, & obesity later in life

Factors contributing to high risk pregnancy

• Socioeconomic status

• Lifestyle factors

• Short inter-pregnancy interval

• High Parity

• Pre-existing health conditions

• Lifestyle Factors

• Mother’s Body Weight

• Underweight - premature membrane rupture, anemia

• Obesity – LGA baby, hypertension, diabetes

Medications & toxins in pregnancy

• Avoid all of them unless approved by a doctor

• May cause: birth defects, bleeding, miscarriage, infant death

• Classifications:

  • A → controlled studies show no risk to fetus

  • B → no controlled studies on humans, animal studies show no risk to fetus

  • C → no controlled studies on humans or animals

  • D → evidence of human risk to fetus, benefits may outweigh risks

  • X → controlled studies in animals & humans demonstrate fetal abnormalities

Mineral metabolism

• Sodium accumulation in mother, placenta, & fetus

• Calcium absorption & mobilization

• Iron stores accumulate in fetus late pregnancy

Pregnancy outcome measures

• Today 2.5% babies die before first birthday

• Most desirable birthweight: 7lb 11oz to 8lb 13oz (3500 to 4000 g)

  • Less likely to develop heart & lung diseases, diabetes, & hypertension for the rest of their lives

Female intra-abdominal fat

reduces SHBG because of elevated blood insulin levels, prompts ovaries to release more testosterone, disrupting egg development.

• Insulin resistance

• Oxidative stress

• Chronic inflammation

• Metabolism syndrome

Male intra-abdominal fat

fat contains aromatase that converts testosterone → estradiol

• Low testosterone & elevated estradiol

  • Increased estradiol inhibits secretion of LH & FSH which can lower testosterone synthesis, then decreases sperm production promoting infertility 

Gestational diabetes

• Carbohydrate intolerance with onset of, or first recognition in, pregnancy.

• It is closely related to type 2 diabetes.