Nutrition

Nutrients

Learning Outcomes

LO2: Understand properties of nutrients.

Assessment Criteria

AC2.1: Explain how nutrients are structured.

Content

Nutrients include:

• Proteins

• Lipids

• Carbohydrates

• Minerals

• Vitamins

• Water

Learners should understand how nutrients are structured and use chemical terms and models.

Good Nutrition

Good nutrition contributes to:

• Physical fitness: strength, stamina, and lots of energy.

• Mental health: ability to concentrate, stay happy, and calm.

• Growth and development: all body systems grow strong, develop properly, and work well.

• Health: good resistance to diseases, ability to recover well from diseases and illnesses.

Malnutrition

Over nutrition:

• Leads to weight gain/obesity.

• Increases risk of diseases like some cancers, type 2 diabetes, heart disease, strokes, and osteoarthritis.

Under nutrition:

• Leads to weight loss.

• Causes weakness.

• Results in failure to grow and develop.

• Increases susceptibility to illness.

Healthy Eating

Good nutrition throughout life promotes health. Healthy eating is defined by:

• Eating a wide variety of foods, mainly plant-based, and mostly unprocessed (wholegrains).

• Drinking plenty of water.

Principles of Nutrition

Assessment Criteria

AC1.1: Describe functions of nutrients in the human body.

Macro Nutrients

Foods that give us energy are classified as macro nutrients. These include:

• Carbohydrates: 4 kcal per gram.

• Protein: 4 kcal per gram.

• Fats: 9 kcal per gram.

Energy Balance

Energy from food is measured in calories (kcal). Excess energy is stored as fat in the body. Caloric intake is influenced by many variables, including:

• Age

• Sex

• Environmental temperature

• Energy expenditure

• Pregnancy

• Hormonal status (thyroxin, catecholamines, and insulin levels)

• Dieting behaviors (e.g., crash diets, intermittent fasting)

Balancing energy intake with energy expenditure is crucial for health. Physical activity helps maintain health.

Calories

Not all calories on food labels are available when digested. Factors include:

• Fibre content: High-fibre foods are difficult to digest, limiting calorie absorption.

• Protein use: Proteins may be diverted for growth rather than energy.

• Fat metabolism: Fat is used as an energy source over carbohydrates in ketosis.

Food choices influence body mass.

Reference Intake

The average adult should consume 2000 kcal per day.

Recommended Daily Intake

• Carbohydrate: At least 260g (4 kcal per gram)

  • Of which sugars: No more than 90g

• Protein: 50g (4 kcal per gram)

• Fat: Less than 70g (9 kcal per gram)

  • Of which saturates: Less than 20g

Example:

• 20g carbohydrate: 20g * 4kcal = 80 kcal

• 20g fat: 20g * 9kcal = 180 kcal

Fat provides more calories than carbohydrates.

Vitamins and Minerals

Reference intake for vitamins and minerals per day:

• Vitamin A: Males 0.7mcg, Females 0.6mcg

• Vitamin D: 10mcg

• Vitamin E: Males 4mg, Females 3mg

• Vitamin K: 1mcg per kg of body weight

• Vitamin B:

  • Thiamin: Males 1mg, Females 0.8mg

  • Riboflavin: Males 1.3mg, Females 1.1mg

  • Vitamin B12: 1.5mcg for both

• Vitamin C: 40mg

• Sodium (Salt): Less than 6g

• Iron: Males 8.7mg, Females (19-50yrs) 14.8mg, (50yrs+) 8.7mg

• Calcium: 700mg

Conversions

• 1 microgram (mcg) = 0.001 milligrams (mg)

• 1 microgram (mcg) = 1000 nanograms (ng)

• 1 milligram (mg) = 1000 micrograms (mcg)

• 1 gram (g) = 1000 milligrams (mg)

Example:

• If you weighed 70kg, how much vitamin K would you need per day?

• Vitamin K: 1mcg * (70kg) = 70mcg

Nutritional Labelling

Colour-coded nutritional information indicates levels of fat, saturated fat, sugars, and salt:

• Red: High

• Amber: Medium

• Green: Low

More green indicates a healthier choice.

Calorie Content

Examples comparing calorie content of different foods:

*Doritos vs. Sabritas
*Irn Bru vs. Haribo
*Greggs Sausage Roll vs. McDonalds Double Cheeseburger
*Lucozade vs. Yorkie
*Pringles vs. Doritos
*Mountain Dew vs. KFC Krush'em
*Haribo vs. Monster Munch
*Haribo vs. Maryland Cookies
*Fish & Chips vs. Chicago Town Pizza
*Crunchie vs. Monster Munch

Key Terminology

Key terminology to help us manage calorie needs

Physical Activity Level (PAL)

• Expresses a person's daily physical activity as a number.

• Used to estimate a person's total energy expenditure.

• Calculates the amount of energy a person needs to consume in order to maintain a particular lifestyle and weight.

Examples:

• Extremely inactive: critical care patient, <1.40

• Sedentary: office worker getting little or no exercise, 1.40-1.69

• Moderately active: construction worker or person running one hour daily, 1.70-1.99

• Vigorously active: agricultural worker or person swimming two hours daily, 2.00-2.40

• Extremely active: competitive cyclist, >2.40

Basal Metabolic Rate (BMR)

• Amount of energy needed to support the body's most basic functions when at rest.

• The number of calories a specific human needs per day to stay alive.

• Can be responsible for 70% of the calories burned per day.

Calculate BMR

The equations use the variable of weight (w) in kilograms, height (h) in centimeters and age (a).

• For men: BMR = (13.75 imes w) + (5 imes h) - (6.76 imes a) + 66

• For women: BMR = (9.56 imes w) + (1.85 imes h) - (4.68 imes a) + 655

Body Mass Index (BMI)

• A measurement of body fat based on height and weight that applies to both men and women between the ages of 18 and 65 years.

• A healthy BMI score is between 20 and 25.

• A score below 20 indicates that you may be underweight; a value above 25 indicates that you may be overweight.

Practice Calculations

Height 153cm weight 56kg
Height 182cm weight 89kg
Height 155cm Weight 120kg
Height 165cm Weight 75kg

Questions

• What are the factors influence appropriate calorie consumption?

• Client a profile: Height 182cm weight 83kg he is very active with a laborious job involving lifting for at least 6 hours of the day. Recommend his calorie intake:

• Explain the differences between BMR and BMI

• Explain what nutritional density means

Respiration

Respiration is the process that the body uses to release energy from digested food (glucose):

glucose + oxygen \rightarrow carbon dioxide + water + energy

from the digestive system + from the breathing system \rightarrow waste product exhaled + waste product exhaled + useful!

Nutrient Density

Nutrient density identifies the amount of beneficial nutrients in a food product in proportion to e.g. energy content, weight or amount of detrimental nutrients. Terms such as nutrient rich and micronutrient dense refer to similar properties. Several different national and international standards have been developed and are in use (see Nutritional rating systems).

• Very low energy density foods = less than 0.6 kcal/g

• Low energy density foods = 0.6 to 1.5 kcal/g

• Medium energy density foods = 1.5 to 4 kcal/g

• High energy density foods = more than 4 kcal/g

ANDI

Examples Nutrient/Calorie Density Scores

• Kale 1000

• Collard Greens 1000

• Mustard Greens 1000

• Watercress 1000

• Swiss Chard 895

• Bok Choy 865

• Spinach 707

• Arugula 604

• Romaine 510

• Brussels Sprouts 490

• Carrots 458

• Cabbage 434

• Broccoli 340

• Chicken Breast 24

• Ground Beef, 85% lean 21

• Feta Cheese 20

• French Fries 12

• White Pasta 11

• Cheddar Cheese 11

• Apple Juice 11

• Olive Oil 10

• White Bread 9

• Vanilla Ice Cream 9

• Corn Chips 7

• Cola 1

High NDI

Low calorie and nutritionally rich.

Poor or Low NDI

Energy dense but nutrient poor.

Biological Value (BV)

Biological value (BV) is a measure of the proportion of absorbed protein from a food which becomes incorporated into the proteins of the body. It captures how readily the digested protein can be used in protein synthesis in the cells of the organism .

• Question: list what a vegetarian cant eat from this list and what a Vegan cant eat from this list

• Discuss: what might be the implications of a child only eating a LBV diet? E.g. a strict Vegan diet?

Complementary Interaction of Proteins

LBV proteins contain fewer Amino Acids than HBV. If a range of LBV foods are eaten then each protein eaten will complement others and altogether they will provide all the essential amino acids – this is called the complementary interactions of proteins

Complimentary Interactions of Nutrients

Many nutritional experts think that looking at the whole diet is essential. Everything they eat and drink over a period of time. Nutrients don’t work individually – they work together in complex chemical interactions to maintain the body and health. In a balanced meal we could be eating a huge range of nutrients and our body can actually control what we need and what we don’t and store what we don’t use or excrete it was waste. We will learn about individual nutrients but its important that you know these are not working alone. Positive interactions happen between a range of nutrients to achieve a range of outcomes

Task: as you write this out if you come across any words that you don’t understand please write them on a separate page – your homework is to research what their meaning is

Questions

• Explain what nutritional density means and give two examples to illustrate your answer

• Explain what Biological value means give two examples to illustrate your answer

Macro and Micro Nutrients

We need macro and micro nutrients in different amounts as they have different roles within our body. Macro nutrients are our main energy providers and therefore we need a lot of them to help our bodies move and function throughout the day. Micro nutrients are only needed in small amounts as some of them the body can produce itself. Micro nutrients are needed to maintain normal cell function on a smaller scale, but they are just as important as macro nutrients as a lack of some micro nutrients can lead to serious health implications.

• Macro nutrients include: Carbohydrates, Protein, Fats

• Micro nutrients include: Vitamins, Minerals

Can you identify any foods containing any of the nutrients listed above?

Key Facts

The human body needs a range of nutrients to function well and be healthy:

• Macro Nutrients Needed in larger amounts Protein, Carbohydrates (& fibre), Fats, Water

• Micro Nutrients Needed in small amounts Vitamins, Minerals

Boron is a required element by our body (only in trace amounts) for the proper metabolism of magnesium, calcium, and phosphorus. Boron helps brain function, healthy bones, and can increase alertness.

Silicon in the body The highest concentration of Silicon in the body is found in connective tissues such as ligaments, tendons and cartilage. This is because it is essential to strengthen structural proteins such as Collagen and Elastin, which are essential for healthy bones and joints. Silicon also encourages the deposition of Calcium into bones.

Carbohydrates

Carbohydrates

Give us energy.
Carbohydrate is the body’s main source of energy (fuel). Carbohydrate breaks down to glucose, which is the only form of energy the brain uses. Basically, without carbohydrate, your brain wouldn’t function!

Key Facts

• The main function of carbohydrate is to provide energy.

• Most cells in the body can use a mixture of fat and carbohydrate for energy.

• Muscle relies on carbohydrate for contraction when the exercise intensity is high.

• The brain however is only capable of using carbohydrate in the form of glucose (sugar).

• No matter in which form carbohydrate enters the body, it is always converted to glucose before it is used by cells.

• The body can store glucose in the form of glycogen in the muscles and liver.

Types of Carbohydrates

The three types of carbohydrates are:

• Starches or complex carbohydrates

• Sugars or simple carbohydrates

• Fibre

Both simple and complex carbohydrates break down into glucose / monosaccharide. A simple carb is one that’s comprised of one or two sugar molecules, while a complex carb contains three or more sugar molecules. Fiber, on the other hand, is found in healthy carbohydrates, but isn’t digested or broken down so is not accessible as an energy. Naturally occurring simple sugars are found in fruit and dairy. There are also processed and refined simple sugars that food companies may add to foods such as soda, sweets, and desserts.

Classification of Carbohydrates

Simple (sugars)

• Table Sugar (sucrose)

• Fruit (fructose)

• Sweets

• Jam

• Marmalade

• Honey

• Energy Drinks (glucose)

• Soft Drinks

• Milk (lactose)

• Glucose

• Fructose

• Galactose

Mix Of Both

• Biscuits

• Cakes

• Cereal

• Sugary Breakfast Cereals

• Starchy Fruit (banana)

• Pastries

Complex (starches & fibres)

• Wheat (bread, pasta)

• Oats

• Corn

• Potatoes

• Rice

• Beans

• Peas

• Lentils

• Chick Peas

• Vegetables

Good vs Bad

All carbohydrates, no matter what type, provide 4kcal of energy per gram. The difference is complex carbs take longer to break down and therefore satisfy hunger for longer, whereas simple sugars leave you feeling empty and wanting more. Complex carbs provide dietary bulk and fibre which makes us feel full!

Amylose and Amylopectin

• Amylose is a straight chain polymer of D-glucose units

• Amylopectin is a branched chain polymer of D-glucose units
  Amylase is the enzyme we produce to break down carbohydrates

Amylose vs. Amylopectin

• It is a straight-chain polymer of D-glucose units

• Constitutes 20% of starch

• It is soluble in water

• Straight chain structure

• It contains a-1,4-glycosidic bonds between two glucose units

Amylopectin vs Amylose

• It is a branched-chain polymer of D-glucose units

• Constitutes 80% of starch

• It is insoluble in water

• Branched structure

• It contains a-1,4-glycosidic bonds between two glucose units in the straight chain and a-1,6-glycosidic bonds at the branching

Chemical Structure

Carbon (C) Hydrogen (H) Oxygen (O), Carbohydrates have the chemical structure C6 H12 O6
During a complex process photosynthesis green plants make carbohydrates using water from the soil and carbon dioxide to provide carbon. Hydrogen and oxygen. In doing this they trap solar energy in the carbohydrate they produce, which in plants (and then animals eat the plants) and release and use them for all their biological processes

Glycosidic bonds

• Cellulose - B glucose, 1-4 glycosidic bonds

• Glycogen - a glucose, 1-4, and 1-6 glycosidic bonds

Polysaccharides

Polysaccharides are long-chain polymers of monosaccharides connected by glycosidic bonds. For example- starch, cellulose, glycogen

• Amylose

• Amylopectin

• Starch

• Glycogen

• Cellulose

Carbohydrate molecules

Chemical structures of monosaccharides, disaccharides, and polysaccharides.

Monosaccharides

Include glucose and fructose.

Disaccharides

Include sucrose and lactose.

Polysaccharide

Glycogen is made of glucose units.

Monosaccharides

• Fructose - fruit and honey

• Galactose - Mammalian breast milk

• Glucose – found in ripe fruit and some vegetables

Molecules

• Fructose molecules are arranged in a pentose ring

• Glucose molecules are arranged in a hexose ring

• Fructose molecules are arranged in a hexose ring

Disaccharides – double sugars

Disaccharides are made during condensation reactions, in which glyosidic bonds/linkages are formed between two monosaccharides

Molecules

H2o or Water From page 68 copy the process of change from a monosaccharide to a disaccharide

Polysaccharides – multiple monosaccharides

Polysaccharides are large molecules made almost entirely from glucose molecules joined together in different formations. They are mostly insoluble in cold water and are not sweet to taste despite being mainly sugars, this is because they are too big to produce a response from the taste buds. Polysaccharides are formed by green plants and are a store of energy in foots, tubers and seeds and as structural strength of stems, shoots and leaves. There are several types of polysaccarides and you need to be familiar with their names.

• Starch – glucose joined together on straight chains and branches

• Dextrin – made when starchy foods are cooked of baked

• Cellulose – cant be digested by humans, its importance is as dietary fiber

• Pectin – formed when lots of glucose is formed into a web and forms a gel with water to make the structure of jams when boiled sugar and acid and then cooled

• Glycogen – made by humans and animals – formed by many glucose polymers as a store of energy in the liver and muscles

Starch

Starch consists of two components Amylose (20 – 25% depending on the plant and Amylopectin (70-80%)

• In amylose the glucose molecules are linked between carbon atoms 1 and 4

• In Amylopectin about one unit of glucose in every twenty is also linked to another glucose molecule in 1-6

Dextrin

Dextrin is produced on the surface of bread and other baked and toasted products by applying dry heat (toasting and baking) which causes changes in the starches in flour. Dextrin give bread extra flavor and colour Maltodextrin is a short chain sugar that is produced by breaking startch down into smaller units of glucose molecule by hydrolysis – it is sometimes used as a food additive

Hydrolysis:

Hydrolysis is any chemical reaction in which a molecule of water ruptures one or more chemical bonds.

Cellulose

Cellulose is a polymer of glucose, . Unlike starch the glucose molecules don’t branch but instead are straight making them firm and strong. Glucose can exist in two forms alpha and beta

• In starch the glucose molecules are joined together in alpha form and joined together by 1,4 glyosidic bonds

• In cellulose the glucose molecules are in the beta form and a joined together by 1,4 glyosidic bonds

Some animals e.g. cattle, sheep and rabbits are able to breakdown cellulose bonds during digestion as their digestive tract has symbiotic bacteria which are able to hydrolyse the 1,4 bonds – humans do not have this bacteria and the cellulose passes through intact

Dietary Fiber

Dietary fiber consists of non-starch polysaccharides and other plant components such as cellulose, resistant starch, resistant dextrin, inulin, lignins, chitins (in fungi), pectin, beta-glucans, and oligosaccharides. These substances are important for helping the movement of waste along the gastrointestinal tract. They are categorised as soluble and insoluble

• Soluble fiber dissolves in the intestines to form a gel. This thickens and soften stools. It also ferments and produces a wide range of metabolites (metabolic chemical reactions) and ongoing research suggests provide wide- range health benefits; and gases

• Insoluble fiber does not absorb or dissolve in water but passes through the digestive system largely unchanged. It provides bulk the faeces to help waste easily be eliminated

1. Where is dietary fiber found?

2. What might happening the body if a person has a low intake of dietary fiber?

3. What might be the longer term complications with a low fiber diet?

From page 71 copy out the table of fiber and the sources

Pectin

Pectin is found inside and between plant cells walls, particularly in fruit and roots. Pectin is important in the food industry for forming gel

Glycogen

Glycogen is produced by humans and some other animals to store glucose in the liver and muscles – its used when we need energy quickly for activities such as running. At the center of each glycogen there is a glycogenin molecule Glycogen is produced during a process called glycogenesis which happens in the liver. The process is controlled by enzymes(glycogenenin and glocogen synthase) and hormones (adrenalin and insulin)

Digestion

1. The mouth Saliva releases an enzyme called amylase, which begins the breakdown process of the sugars in the carbohydrates you’re eating.

2. The stomach Your stomach makes acid to kill bacteria in the food

3. The small intestine, pancreas, and liver from the stomach into the small intestine, this causes the pancreas to release pancreatic amylase. This enzyme breaks down the chyme into dextrin and maltose. From there, the wall of the small intestine begins to make lactase, sucrase, and maltase. These enzymes break down the sugars even further into monosaccharides or single sugars. These sugars are the ones that are finally absorbed into the small intestine. Once they’re absorbed, they’re processed even more by the liver and stored as glycogen. Other glucose is moved through the body by the bloodstream. The hormone insulin is released from the pancreas and allows the glucose to be used as energy.

4. Colon Anything that’s left over after these digestive processes goes to the colon. It’s then broken down by intestinal bacteria. Fiber is contained in many carbohydrates and cannot be digested by the body. It reaches the colon and is then eliminated with your stools.

Digestion of Carbohydrates

Salivary a-amylase \rightarrow Dextrins
Dietary Carbohydrates
Dextrins Pancreatic a-amylase \rightarrow Maltose Sucrose Lactose
Maltase Sucrase Lactase
Monosaccharides
Glucose Fructose Galactose

Questions

• Research and explain what Hydrolysis is and how it relates to carbohydrates

• Explain what Amylopectin is and which polysaccharide it’s links too

• Explain the digestive process of change from a monosaccharide to a disaccharide

• What reaction is linked to glyosidic bonds/linkages

• Explain Glycemic index

• Why is glycemic index particularly important to individuals with diabetes?

Fibre

• Where is dietary fiber found?

• What might happening the body if a person has a low intake of dietary fiber in the short term?

• What might be the longer term complications with a low fiber diet?

Protein

Protein

Growth and Repair
Protein is essential for the growth, maintenance and repair of body tissue. Protein is part of every living cell and some tissues like skin, muscle, hair and the core of bones and teeth!

Chemical Composition

Carbon Hydrogen Oxygen Nitrogen Phosphorus Sulphur
These elements arranged into chemical units are called Amino acids which are joined together in long chain, Polymers, to form proteins. All living things contain proteins, In humans there are twenty Amino Acids that are important These twenty Amino Acids join together in thousands of different sequences to form a vast number of different proteins that are found I the body. All amino acids have the same formula

Peptide Bonds

Amino acids joined together to other amino acids by Peptide Bonds. These are formed when the amino acid of one amino acids with the carboxyl group of another amino acid with the loss of water called the condensations reaction.

Stages of folding a protein molecule

• Stage 1 Polypeptide chain.

• Stage 2 Secondary structure . Polypeptides chains either twist into a helix or fold into concertina shaped sheet – this help forms bonds between polypeptides chains. Some of the Amino Acids are hydrophobic and some are hydrophilic – this influences how the polypeptides fold or twist

• Stage 3. The Polypeptides chains fold more and more so that the protein molecule becomes more compact and more bonds are formed

• Stage 4. At the final stage several folded polypeptides chains join and fold together to form compact bundles.

Denaturation

Heat, mechanical action and pH. can disturb and break down the bonds in protein together and cause them to unravel – this is denaturation

can you give examples of when a protein will denature?

Protein Digestion

Stomach acid and enzymes (pepsin), break long chains into short segments

Whole Protein Chain \rightarrow Peptide Fragments

Pancreatic juices break bonds further, in the intestine, \rightarrow Amino acids enter intestinal wall cells via active transport or endocytosis
DNA provides instructions to build antibodies & hemoglobin, muscle fibers, collagen in skin, & other cell structures
Amino Acids

Enzymes put back the molecule of water and break the bonds of the peptides – this is called hydrolytic reactions or hydrolysis (hydro = water lysis = set free) The amino acid is absorbed into the blood stream and taken to the liver where they are reorganised into new proteins that are needed on the body

• Most amino acids can be made in the body this way – these are called nonessential amino acids

• Some amino acids cant be made in the body and these are essential amino acids

• There are two that are conditionally essential – these are needed by children and adults but not by adults

Protein sources

Animal Proteins (HBV)
Meat Tofu
Fish Pulses

• Poultry Nuts

• Dairy Products Grains

• Eggs Soya (HBV) Cereals TVP (textured vegetable protein)

Calculate the amount of protein each person needs based on the following calculation:
Protein needs per day = 0.8g * body weight (kg)
80g, 56g, 68.8g, 43.2g, 72kg
What is the link between body weight and how much protein the body needs?
What could low in take of protein lead to?

Vegan Diets

A vegan diet contains only plants, such as vegetables, grains, nuts and fruits, and foods made from plants. Vegans don't eat foods that come from animals, including dairy products and eggs. A healthy vegan diet contains:

• plenty of fruit and vegetables

• plenty of starchy foods

• some non-dairy sources of protein, such as beans and pulses

• some dairy alternatives, such as fortified soya drinks

• just a small amount of fatty and sugary foods

Vegetarian Diet

For vegetarians who eat dairy products and eggs, a healthy diet is the same as for anyone else but without meat or fish. A healthy vegetarian diet contains plenty of fruit and vegetables and starchy foods, some non-dairy sources of protein such as eggs and beans, some dairy products and just a small amount of fatty and sugary foods.

People following a strict vegetarian or vegan diet need to choose a variety of protein sources from a combination of plant foods. Plant foods do not have complete proteins, but by eating combinations of plant foods, called ‘complementary proteins’ you can obtain a complete protein and get the required balance of amino acids.

Fats

Functions of Fat

• Protection of internal organs

• Thermoregulation (temperature control)

• Insulation of nerve cells (conduct electrical messages)

• Uptake of fat soluble vitamins (A, D, E & K)

• Growth, development and repair of body tissues

• In women, storage and modification of reproductive hormones (oestrogen)

• Flavour - fat in food improves ‘mouth feel’ takes longer to digest ‘satiety value’.

• ‘Grease’ food to make it easier to swallow

• Essential fatty acids – Omega 3 and 6

Chemical formula C₃H₈O₃
Fats and oils are chemically the same and have the same energy value, but fats are solid and oils are liquid at room temperature. Fats contain Carbon, oxygen and Hydrogen. There are arranged into triglycerides – which consist of one unit of glycerol and three fatty acids

Triglycerides – a fat molecule consisting of one molecule of glycerol and 3 fatty acids

TRI - 3

Structure of fat. Triglycerides account for around 95\% of the fat in our diet, and are formed from the combination of glycerol and three fatty acid molecules. The three fatty acids are often different, and the chemical structures of these fatty acids defines the type of fat. Cholesterol is made in the liver, and transported around the body by low density lipoproteins (LDL) and high density lipoproteins (HDL). Different fats affect LDL and HDL differently.

Building blocks for fatty acids

At least 40 fatty acids are known to exist ‘’R’’ is different in each fatty acid and is made up of carbon and hydrogen atoms.

• Different combinations of fatty acids combine with glycerol to form a wide variety of fat molecules

• Three fatty acids combine with glycerol but condensation reaction to form triglycerides like this(

• There are also diglycerides (two fatty acids) and monoglycerides (one fatty acid)

Saturated and unsaturated

Fatty acids are either Saturated or Unsaturated

• Saturated fats contain as many hydrogen atoms as they can take

• Unsaturated are not at full capacity and contain one or more double bonds between carbon atoms

• Monounsaturated fatty acids have _ double bond

• Polyunsaturated contains _ double bonds

*One
*Two or more

Which is the healthy fat?

Hydrogenated fats Unsaturated fats can except more hydrogen which will bond to the carbon when the double bonds are broken. This process happens when solid fats are made from liquid fats – can you think of an example?
This is also referred to as Transfats

• Saturated fat: a fatty acid with single bonds and as many hydrogen atoms as it can hold

• Monounsaturated fat: a fatty acid with one double bond

• Polyunsaturated fat: a fatty acid with two or more double bond

The shape of a fatty acid molecules affects the working properties of ingredients in food preparations that contain them.

• Their plasticity (ability to spread and shape) and their melting point

• It also influences how they are used in the body and how they effect health

The shape of fats

• Saturated tend to be straight and are rigid and has a high melting point and is difficult to spread at room temperature

• Unsaturated fatty acids have double bonds – these can either be cis or trans . The more cis bonds a fatty acid has the more curved it becomes stopping them pack closely together which means lower melting point

Cis Transformation and Trans bonds.

The key difference between cis and trans fatty acids is that the cis fatty acids have two hydrogen atoms attached to the double bond in the same side of the carbon chain

Vitamins:

Vitamins: Functions, Sources, and Side Effects

Fat-Soluble Vitamins

Vitamin A

• Function: Maintains healthy vision, immune system, skin, and mucous membranes; supports cell growth and reproduction.

• Sources:

  • Liver, fish liver oils

  • Eggs

  • Dairy (milk, cheese, butter)

  • Orange/yellow/red fruits & vegetables (carrots, sweet potatoes, pumpkins, mangoes)

  • Dark green leafy vegetables (spinach, kale)

• Side Effects:

  • Deficiency: Night blindness, dry skin, increased infection risk

  • Excess: Toxicity causing headaches, dizziness, nausea, liver damage, birth defects (in pregnancy)

Vitamin D

• Function: Aids calcium absorption, supports healthy bones and teeth, regulates immune function.

• Sources:

  • Sunlight exposure (skin makes vitamin D)

  • Oily fish (salmon, mackerel)

  • Egg yolk

  • Fortified milk and cereals

• Side Effects:

  • Deficiency: Rickets (children), osteomalacia (adults), muscle weakness

  • Excess: Hypercalcemia (too much calcium in blood) leading to kidney stones, nausea, confusion

Vitamin E

• Function: Antioxidant (protects cells from free radicals), immune function, skin health.

• Sources:

  • Vegetable oils (sunflower, safflower)

  • Nuts and seeds

  • Green leafy vegetables

  • Fortified cereals

• Side Effects:

  • Deficiency: Rare, but can cause nerve and muscle damage

  • Excess: Increased bleeding risk, especially if on anticoagulants

Vitamin K

• Function: Blood clotting, bone metabolism.

• Sources:

  • Green leafy vegetables (kale, spinach)

  • Broccoli, brussels sprouts

  • Liver

  • Some produced by gut bacteria

• Side Effects:

  • Deficiency: Bleeding disorders, easy bruising

  • Excess: Rare, but can interfere with blood thinning medications

Water-Soluble Vitamins

Vitamin C (Ascorbic Acid)

• Function: Collagen synthesis, wound healing, immune function, iron absorption.

• Sources:

  • Citrus fruits (oranges, lemons)

  • Berries

  • Peppers

  • Tomatoes

  • Broccoli

• Side Effects:

  • Deficiency: Scurvy (bleeding gums, fatigue, joint pain)

  • Excess: Diarrhea, stomach cramps

Vitamin B1 (Thiamine)

• Function: Energy metabolism, nerve function.

• Sources:

  • Whole grains

  • Pork

  • Legumes

  • Nuts and seeds

• Side Effects:

  • Deficiency: Beriberi (weakness, nerve problems), Wernicke-Korsakoff syndrome (confusion)

  • Excess: Rare, excess is excreted

Vitamin B2 (Riboflavin)

• Function: Energy production, healthy skin, vision, nerve function.

• Sources:

  • Dairy

  • Eggs

  • Green leafy vegetables

  • Lean meats

• Side Effects:

  • Deficiency: Cracked lips, sore throat, inflamed tongue

  • Excess: Harmless bright yellow urine

Vitamin B3 (Niacin)

• Function: Energy metabolism, skin health, nervous system function.

• Sources:

  • Meat, poultry, fish

  • Whole grains

  • Legumes

  • Peanuts

• Side Effects:

  • Deficiency: Pellagra (diarrhea, dermatitis, dementia)

  • Excess: Flushing, liver damage

Vitamin B5 (Pantothenic Acid)

• Function: Energy metabolism, hormone synthesis.

• Sources:

  • Whole grains

  • Meat, poultry

  • Eggs

  • Avocado

• Side Effects:

  • Deficiency: Rare, but may cause fatigue, numbness

  • Excess: Rare, may cause diarrhea

Vitamin B6 (Pyridoxine)

• Function: Protein metabolism, red blood cell formation, brain function.

• Sources:

  • Meat, poultry, fish

  • Whole grains

  • Bananas

  • Nuts

• Side Effects:

  • Deficiency: Anemia, depression, confusion

  • Excess: Nerve damage (tingling, numbness)

Vitamin B7 (Biotin)

• Function: Metabolism of fats, carbohydrates, protein, healthy hair and skin.

• Sources:

  • Eggs (yolk)

  • Nuts

  • Soybeans

  • Whole grains

• Side Effects:

  • Deficiency: Rare, but can cause hair loss, dermatitis

  • Excess: No known toxicity

Vitamin B9 (Folate/Folic Acid)

• Function: DNA synthesis, cell division, red blood cell formation.

• Sources:

  • Green leafy vegetables

  • Fortified cereals

  • Legumes

  • Citrus fruits

• Side Effects:

  • Deficiency: Neural tube defects (in pregnancy), anemia

  • Excess: Masks vitamin B12 deficiency

Vitamin B12 (Cobalamin)

• Function: Nerve function, red blood cell formation, DNA synthesis.

• Sources:

  • Animal products (meat, fish, eggs, dairy)

  • Fortified plant-based milk and cereals

• Side Effects:

  • Deficiency: Anemia, nerve damage, fatigue

  • Excess: Rare, usually excreted in urine