food nutrition Flashcards
(33 cards)
FOOD NUTRIENTS: carbs, proteins, lipids
CARBS: provide most of the energy in the human diet.
PROTEIN: build and repair muscles and bones
LIPIDS: store energy, regulate hormones, aid digestion
FOOD NUTRIENTS: vitamins, minerals, water
VITAMINS: necessary for the body to function well and are required in small amounts.
fight off infections, keep nerves healthy, help the body get energy from food and help blood to clot properly.
MINERALS: essential in the diet as they cannot be created by the body. The body uses minerals for many different jobs, including keeping your bones, muscles, heart, and brain working properly.
-some are required in larger amounts (macro-minerals) including calcium, magnesium, sodium, potassium.
-micro-minerals are required in much smaller amounts, including iron, zinc, iodine.
WATER: prevents dehydration and replenishes liquid lost through perspiration
STRUCTURE OF: carbs
made of -
SIMPLE - SUGARS:
1. monosaccharides - single sugar molecules (glucose and fructose)
2. disaccharides - two sugar molecules together (glucose + fructose = sucrose, glucose + galactose = lactose)
COMPLEX - STARCHES/DIETARY FIBRE:
3. polysaccharides - many sugar molecules (starch and glycogen)
STRUCTURE OF: proteins
formed when amino acids link together: amino acids are made up of nitrogen, oxygen, carbon and hydrogen
8 essential amino acids are required by the body through food
-essential for growth and maintenance
-energy source
-contain antibodies to prevent illness
STRUCTURE OF: lipids
fats and oils made up of carbon, hydrogen and oxygen e.g. butter, cooking oil and pastry
FATTY ACIDS: chains of carbon atoms joined together with 4 H+ atoms and 2 O2 atoms e.g. fish and flaxseed
TRYGLYCERIDES: 95% of the fat in our diet. It is formed when three fatty acids combine with glycerol e.g. sugary foods and drinks
STEROLS: 1% of the total lipids in the diet are created when many fatty acids combine with glycerol. The most common is cholesterol. Most is made in the liver, but about 25% comes from our food
PHOSPHOLIPIDS: eggs, fish, meats
SOURCES OF: carbs, proteins, and lipids
CARBS: cereals, pasta, breads
PROTEINS: eggs, legumes, dairy, fish, chicken, meat
LIPIDS: avocado, olives, tuna/salmon, cream, processed foods
SOURCE OF: vitamins, minerals, water
VITAMINS:
1. vitamin a: potato, carrots, spinach
2. vitamin d: dairy products
3. vitamin e: leafy green vegetables, seeds, nuts
MINERALS: meat, dairy, nuts, cereals
WATER: cucumber, water, tomato
FUNCTIONS OF: carbs, proteins and lipids
CARBS: to provide energy to maintain breathing, regulate body temperature, keep the heart pumping, and ensure that all organs are functioning.
PROTEINS: creates, replaces, and repairs cells
LIPIDS: insulate body heat, protect organs, concentrated source of energy
FUNCTIONS OF: vitamins, minerals and water
VITAMINS: blood clotting (k,) absoprtion of calcium (d,) support vision and healthy skin (a)
MINERALS: strengthen teeth and bones (calcium,) metabolise energy levels (iron,) support the immune system (zinc)
WATER: regulate body temperature, flushes urine, supports cell growth
SIGNIFICANT INTERRELATIONSHIPS: iron and vitamin c
iron and vitamin c work together in the synthesis of red blood cells, as iron is a vital part of hemoglobin, found in red blood cells, and vitamin C is essential for the integrity of the blood vessels.
-eat iron-rich foods along with citrus fruits or greens at the same
SIGNIFICANT INTERRELATIONSHIPS: iron and fibre
too much fibre in foods can bind with iron and not allow it to be absorbed into the blood.
-if you consume fibrous grains at the same time as red meat, your body does not absorb iron as effectively.
SIGNIFICANT INTERRELATIONSHIPS: calcium and phosphorus
both required for the formation, absorption and maintenance of calcium phosphate, which gives bones and teeth their strength.
-if calcium levels rise, phosphorus levels fall and vice versa.
-dairy foods have calcium, phosphorus and lactose content
SIGNIFICANT INTERRELATIONSHIPS: calcium and vitamin d
vitamin d promotes the absorption of calcium. without vitamin d we cannot make use of the calcium in food, resulting in weak bones and teeth.
-fish and dairy at the same time would help absorb these micro-nutrients.
SIGNIFICANT INTERRELATIONSHIPS: calcium and fibre
insoluble fibre cannot be processed in the digestive system, so it is best to eat dairy and fibre separately.
SIGNIFICANT INTERRELATIONSHIPS: calcium and lactose
lactose increases calcium absorption
SIGNIFICANT INTERRELATIONSHIPS: folate and vitamin b12
folate helps prevent certain forms of anemia and is necessary to metabolise amino acids.
-both folate (green leafy vegetables) and B12 (meat, fish, poultry) are essential for normal growth.
-having an insufficient amount of one of these nutrients may prevent the others from doing their jobs properly, e.g. the formation of healthy red blood cells
SIGNIFICANT INTERRELATIONSHIPS: sodium and potassium
potassium and sodium influence overall cardiovascular well-being. If the diet contains too much sodium compared to potassium, the imbalance can increase the risk of developing high blood pressure and/or heart disease.
digestion, absorption and metabolism of food
Digestion is the complex process of breaking down the food eaten into nutrients, which the body absorbs for fuel in order to survive.
mechanical and chemical breakdown of food:
1. mechanical breakdown occurs through chewing and peristalsis (the wave-like movement of the muscles in the gastrointestinal tract)
2. chemical breakdown occurs at secretions and enzymes react with the food.
absorption takes place when these components move from the gut into the blood and lymphatic systems of the body. This is the delivery system for the nutrients.
metabolism is all the chemical processes that use nutrients to make other substances required by the body:
1. catabolism: the breaking down of nutrients into their components, usually in the form of energy
2. anabolism: new substances are made from the components derived from catabolism. For example, anabolism is involved in the making of new proteins required when the body is repairing muscle tissue.
the digestive system: steps
- mouth, teeth, salivary glands:
-process of chewing, which breaks down food into smaller pieces.
-salivary glands create saliva, containing enzymes, which initiates the chemical breakdown of carbohydrates into simpler sugars. - esophagus:
-once food is swallowed, it moves down the esophagus, a muscular tube connecting the mouth to the stomach. - stomach:
-a highly acidic environment where gastric glands create hydrochloric acid and enzymes to break down proteins into smaller polypeptides.
-stomach’s muscular walls churn and mix the food with gastric juices. - small intestine:
-chyme is released here, where most digestion and nutrient absorption occur.
-pancreas releases pancreatic enzymes, which continue the breakdown of fats, proteins, and carbohydrates.
-liver produces bile, which is stored in the gallbladder and released into the small intestine to aid in fat digestion and absorption. - large intestine:
-remaining undigested food, water, and waste products pass into the large intestine.
-water and electrolytes are absorbed from the undigested food, forming feces.
-beneficial gut bacteria ferment undigested carbohydrates, producing gases and vitamins. - rectum and anus:
-feces are stored in the rectum until they are ready to be removed via the anus
DIGESTION, ABSORPTION AND METABOLISM: lipids
DIGESTION:
-starts slowly in the mouth, then in the stomach, a lot of churning takes place that helps to break fat down into smaller components.
-majority of fat digestion occurs in the small intestine, where bile emulsifies fat molecules.
ABSORPTION AND METABOLISM:
-small molecules of digested lipids can diffuse into the intestinal cells and absorb directly into the bloodstream.
-the blood carries these fats to the rest of the body for use or storage.
DIGESTION, ABSORPTION AND METABOLISM: proteins
DIGESTION:
-crushed and churned in the mouth but most of the digestion takes place in the stomach.
-denatured by stomach acids in order for pepsin to digest proteins down to their simplest amino acid form.
ABSORPTION AND METABOLISM:
-specific carriers transport amino acids into the intestinal cells, where they are used for energy or to synthesize necessary proteins.
DIGESTION, ABSORPTION AND METABOLISM: carbs
DIGESTION:
-amylase found in saliva starts to break down carbohydrates in the mouth. The small intestine performs most of the digestion of carbohydrates.
-pancreatic amylase is responsible for breaking all polysaccharides and disaccharides down to monosaccharides.
ABSORPTION AND METABOLISM:
-most nutrient absorption takes place in the small intestine. blood from the intestines circulates through the liver, and cells take up simple sugars and convert them to other compounds.
DIGESTION, ABSORPTION AND METABOLISM: vitamins
DIGESTION:
-fat-soluble vitamins (A,D,E and K) require fats to carry them via the bloodstream to the liver and other fatty tissues.
-water-soluble vitamins (B and C) are digested and carried into the blood through the intestine.
-the small intestine = vitamin digestion and absorption.
ABSORPTION AND METABOLISM:
-water-soluble vitamins are picked up in the small intestine. The vitamin molecules are carried through the intestine’s cell wall to where they can enter the bloodstream.
-fat-soluble vitamins need to be dissolved in fat before they can enter the body. Fat-digesting bile acids break down the fat, and vitamins move through the intestinal wall, into the body, and are stored in the liver and in body fat.
DIGESTION, ABSORPTION AND METABOLISM: minerals
DIGESTION:
-the digestive trace releases minerals so they are made available for absorption.
ABSORPTION AND METABOLISM:
-predominantly takes place in the small intestine.
-once absorbed they are sent to required areas of the body.
