Week 5: Vitamins, Phytochemicals, and Cancer (PDF)

WEEK 5: VITAMINS, PHYTOCHEMICALS AND CANCER (23 SEPTEMBER 2024) Cancer Background 2nd leading cause of death in US Majority of cancers have lifestyle factors and environmental exposure as major risk factors ❖ 30-40%: diet...

WEEK 5: VITAMINS, PHYTOCHEMICALS AND CANCER (23 SEPTEMBER 2024) Cancer Background 2nd leading cause of death in US Majority of cancers have lifestyle factors and environmental exposure as major risk factors ❖ 30-40%: diet Risk factors Nonmodifiable (1) Family history ❖ Some genes raise the risk for certain types of cancer ❖ Families also may share health related habits and environmental exposures (2) Age ❖ Greater exposure to carcinogens ❖ Cellular repair systems decline (3) Sex ❖ Breast cancer rates higher in women → greater production of estrogen (4) Reproductive history ❖ Age of menstruation and menopause ❖ Pregnancy and breast-feeding history Modifiable (1) Physical inactivity ❖ Correlates with most major disease (including cancer) (2) Chemicals (a) Can exist in water, soil and food (mercury, lead,  and arsenic) (b) Pesticides linked to increased cancer risk - Solution: reduce pesticide exposure (c) Stimulate cell division, cause mutations and disrupt normal hormones (3) Microorganisms (a) Viruses, bacteria, parasites, fungi (can be found in food) → cancer Commented : liver inflammation (b) Hepatitis B and C → liver cancer (c) Food + mold = aflatoxin → raise risk of liver cancer - Solution: safety guidelines limit aflatoxin in foods (4) Tobacco ❖ Includes cigarettes, cigar, pipe and electronic cigarettes (including vapes) ❖ Increases risk of 15 types of cancer (5) Alcohol ❖ Excessive drinking increases the risk of cancer in the mouth, throat, voice box, esophagus, liver, breast and possibly pancreas *Alcohol + tobacco = greatly increases cancer risk* (6) Diet ❖ Processed meats increases cancer risk Eg: hot dogs, bologna, ham, sausage and bacon ❖ Studies link low fiber diet to increased cancer risk (7) Overweight and obesity  ❖ Increases the risk of some cancers ❖ Obesity can increase inflammatory chemicals, insulin, estrogen and insulin-like growth factors Commented : insulin: hormones that are produced in pancreas --> regulating blood sugar levels Reducing risk of (1) Limit alcohol intake insulin-like growth factors: proteins that have a similar structure to insulin; produced in the liver --> growth and cancer ❖ Men: 2 drinks/day development Commented : insulin: hormones that are produced in ❖ Women: 1 drink/day pancreas --> regulating blood sugar levels ❖ Those with family history of breast cancer → avoid insulin-like growth factors: proteins that have a similar structure to insulin; produced in the liver --> growth and development alcohol (2) Maintain a healthy weight (3) Be physically active ❖ Maintain healthy body weight → enhances anti- tumor immunity + reduces risk of some cancers ❖ Physical activity in those with cancer has benefits (4) Eat a plant-based diet ❖ Contain vitamins, minerals, fiber, healthy fats, antioxidants and anti-inflammatory compounds ❖ Contain phytochemicals (5) Avoid plastic water bottles ❖ Unless they are free of bisphenol A (BPA) ❖ BPA can damage DNA and mimic estrogen Vitamins General Essential Characteristics Produce deficiency symptoms when missing from diet Commented : fat-soluble: A DE(E)K water-soluble: cb (iw drown cb) Yield no energy Commented : do it Fat (lipid) soluble vitamins (A,D,E,K)  ❖ Absorbed with fat ❖ Stored in large amounts - Deficiency takes a long time ❖ Highly toxic - especially Vitamin D and A (usually from overuse of supplements) Water soluble vitamins (C and B – Vitamin B6, B12, thiamin, niacin, folate, riboflavin, biotin and pantothenic acid) ❖ High doses excreted (urine) ❖ Stored in small amounts - Deficiency faster to develop due to limited stores ❖ Usually less toxic Vitamin C Characteristics Water soluble Antioxidant nutrient Food sources Most (fresh) fruits and vegetables Eg: Citrus, tomatoes and potatoes Least stable vitamin ❖ Easily lost in storage, processing and cooking Functions (1) Collagen formation ❖ Forms connective tissue Eg: skin, blood vessels (2) Iron absorption ❖ Improves absorption of iron (3) Immune function ❖ Protects white blood cells from oxidative damage  (4) Antioxidant ❖ Donating an electron to free radicals ❖ Studies suggest Vitamin C may reduce risk of cancers of mouth, esophagus, stomach and lungs ❖ Studies have shown vitamin C supplements do not reduce cancer risk ❖ Food sources will be the best 👍 Commented : important Deficiency Scurvy (severe lack of Vitamin C) Commented : impt to note (simpeh talked about it a few times) ❖ Prevents normal synthesis of collagen → pinpoints Commented : jeeez rly ah hemorrhages (bruises), bleeding gums ❖ Anemia Toxicity Upper level is 2 g/day High intake → cause gastrointestinal effects and increase the risk of kidney stones Groups at risk Alcoholics Poverty Vitamin A Food sources Retinoids ❖ Biologically active form of Vitamin A ❖ Found in animal products Eg: liver, fish, fortified milk, eggs Carotenoids ❖ Beta-carotene Eg: carrots, spinach, squash, sweet potatoes, cantaloupe, peaches  ❖ Can be converted to Vitamin A in the body Beta-carotene: Consumption of fruits and vegetables rich in beta Antioxidant role carotene → associated with reduced risk of lung cancer ❖ Recommend foods sources of beta carotene Studies of beta-carotene supplements showed increased risk of lung cancer Functions (1) Growth and development ❖ Retinoids play an important role in embryonic development (2) Immune function ❖ Vitamin A helps maintain the epithelium (a barrier that protects the body against the entry of disease pathogens) (3) Vision ❖ Needed in the retina of the eye to turn visual light into nerve signals in the brain - Rods: vision in dim conditions - Cones: vision in light conditions Deficiency Rare in the US as vitamin is abundant in their food supply Still occurs in low income countries ❖ Major cause of non-accidental blindness → xerophthalmia (eyes loses ability to produce mucous → bacteria invasion and dryness occurs) Groups at risk Alcoholics  Liver disease (limit storage of Vitamin A) Severe fat malabsorption Toxicity Pregnancy ❖ Malformation of fetus Acne drugs that contain Vitamin A can be toxic to the fetus Vitamin E Food sources Vitamin E is susceptible to destruction from oxygen, light and heat Eg: Plant oils, wheat germ, avocado, peanuts and sunflower seeds Functions Antioxidant ❖ Protects cell membranes from free radical damage ❖ Mixed results on Vitamin E supplements to protect against cancer ❖ Food sources are the best 👍 Deficiency Rare in humans Those with fat malabsorption (cystic fibrosis or Crohn’s disease) Preterm infants at risk Can cause hemolytic anemia Phytochemicals What is it? Chemical substances found in plants that affect health Not essential – not classified as nutrients  Obtained through diet Functions Provide color, flavor and odor to food Found in plants (fruits and vegetables) Over 4000 identified Phytochemicals & Disease What it prevents Cancer Heart disease Diabetes Hypertension How do they work? (1) Compete with cholesterol for absorption → reducing absorption of cholesterol (2) Stimulate the activity of enzymes that deactivate carcinogens (3) Mimic the body’s own hormones (4) Act as antioxidants ❖ Compounds that protect other compounds from damaging reactions Types of Carotenoids (beta-carotene, lycopene, lutein) phytochemicals (8) Health benefits: acts as antioxidants, possibly reducing Commented : Important for exam 2 the risk of cancer 👍 Food sources: tomatoes, cantaloupe, carrots, broccoli, sweet potatoes Flavonoids Health benefits: acts as antioxidants; inhibit cell proliferation 👍 Food sources: grapes, green and black tea, citrus  fruits, soybeans, whole wheat Capsaicin Commented : does not have a role in cancer but have a role in protecting against cvd Health benefits: modulates blood clotting, possibly reducing the risk of stroke/heart attack 👍 Food sources: hot peppers Allicin Health benefits: may lower blood cholesterol 👍 Food sources: chives, garlic, leeks and onions Genistein Commented : mimic estrogen in body Health benefits: reduce risk of breast, colon and prostate cancer; reduce risk of osteoporosis 👍 Food sources: soybeans, soymilk, tofu, legumes Curcumin Health benefits: acts as antioxidant and anti- inflammatory agent 👍 Food sources: turmeric (yellow-colored spice) Lignans Health benefits: phytoestrogen that blocks estrogen activity in cells → reducing risk of breast, colon and prostate cancer 👍 Food sources: seeds, whole grains, soybeans, lentils, broccoli Resveratrol Health benefits: acts as antioxidants; may reduce inflammation; decrease blood clot formation 👍  Food sources: red wine, grapes, raspberries Ways to increase Fresh is best phytochemical ❖ Canned tomatoes 🍅 included (good source of intake phytochemicals) Leave skin on when possible Steam, broil, stir fry when you cook ❖ Avoid boiling Eat a variety of foods ❖ Try new foods (a new fruit/vegetable/whole grain each week) Increase servings of fruit and vegetables Eat a variety of brightly colored foods Use herbs and spices in cooking Phytochemical No RDA’s set for phytochemicals (still a lot we don’t Commented : Recommended Daily Allowances Supplements know about phytochemicals like toxicity) Many phytochemicals act together ❖ Phytochemicals can alter body functions ❖ Can have negative effects in high doses Safest source of food ❖ Consuming diets rich in fruits, vegetables, legumes, other whole foods ❖ A single food can contain 1000 phytochemicals WEEK 6: WATER AND MINERALS (30 SEPTEMBER 2024) Water Characteristics Most essential nutrient 50-70% of body weight is fluid ❖ Depends on age and body fat content Intracellular fluid – within the cell Extracellular fluid – outside the cell ❖ Fluid between cells and intravascular fluid Functions (1) Maintaining blood volume allowing for transport of nutrients and oxygen (2) Forming specialized fluids Eg: saliva, tears, bile and amniotic fluid (3) Lubricant for joints (4) Solvent ❖ Help dissolve minerals  (5) Keeping exposed tissues moist Eg: Eyes, nose, mouth and skin (6) Regulating body temperature ❖ When overheated: body perspire → sweat evaporates through pores → heat removed from skin → body cooled ❖ Water input: fluids, water content of food, water produced in body ❖ Water output: skin perspiration, lung respiration, waste products (urine, feces) (7) Removing waste products like urine Increased fluid (1) Hot, humid conditions needs (2) Exercise (3) High protein diet ❖ Nitrogen part of protein can’t be used for energy and has to be excreted as urea (4) Higher fiber diet (5) Alcohol: diuretic (6) Illness Eg: vomiting, fever, diarrhea Dehydration Characteristics Urine color: dark urine, low volume ❖ Normal: pale yellow 1 lb loss = 2 cups of fluid Commented : Important for exam 2 Early dehydration: thirst Advanced dehydration: muscle spasms, sunken eyes, Commented : aka walking zombie delirium, death Commented : disoriented, confused, not able to think clearly  Symptoms (1) Headache (2) Dry mouth (3) Dark urine Minerals Types of minerals Major minerals Require >100mg/day Eg: calcium, phosphorus, sodium Trace minerals Require