THE 7 ESSENTIAL COMPONENTS OF A HEALTHY DIET
Making Informed choices about active, healthy
lifestyles
Learning Objectives
Identify the components of a healthy diet and their functions
Describe the components of a healthy dietExplain the importance of each type of component
Balanced, healthy diet
What is it?Having a HEALTHY and BALANCED diet... So eating the right foods and eating the right amounts of these foods
The following are the main nutrients or essential components the body needs:
CarbohydratesFatsProteinVitaminsMineralsWaterFibreYou need to know that getting the 1) right amount of these nutrients 2) being hydrated 3) having a positive energy balance, will mean you have a balanced, healthy diet
Carbohydrates
These are made up of the chemical elements carbon, hydrogen and oxygen.
Their main job - Make energyThere are two types:1. Simple sugars: provide quick energy, e.g. (Glucose or
fructose)2. Complex starches: these have many sugar units, and will
release energy slower e.g. (Potatoes or pasta)Carbohydrates are vital for athletes – 1. especially intense
exercise (for energy), 2. also they help the nervous system work and also 3. help to metabolise fat (use fat for energy)
Carbohydrates
Carbohydrates are stored in the muscles and liverStored as GLYCOGEN, but only in limited amounts, so
will need to be replenished During exercise:Glycogen (in muscles and liver) are broken down to
glucose, this is then used to produce energy to exercise
When glycogen stores are depleted, there is less energy available and you become fatigued
Carbohydrates
Men should be eating roughly 2,500 calories a day, women should be eating 2,000 calories a day.
This means 313grams of carbohydrates a day for a man and 250grams per day for a woman
The recommendation is that 60% of your diet is carbohydrates
Michael Phelps, the Olympic gold medallist at Beijing 2008, reportedly ate 12,000 calories during the events
Carbohydrates (Pg 86)
Name 5 sources of simple and complex carbohydrates:Simple:12345Complex12345
Fats
These are also very important to a healthy diet, and a major source of energy, especially low intensity endurance exercise
Fats or Lipids are made up of hydrogen, carbon and oxygen, but in different proportions to Carbo’s
Two types:Triglycerides – stored as body fatFatty acids – used to produce energy, either saturated
or unsaturated
Fats
How do you work out your BMI? (Pg 87)What is being obese?What is being overweight?What can being obese cause?
Saturated and Unsaturated Fats
Saturated
Unsaturated
Fats
When muscles have a ready supply of oxygen, fat is used for energy ahead of carbo’s.
It does this to save the GLYCOGEN (Carbo’s) for intense work
However your body cannot solely use Fat as a energy source, so it uses a combination fo FAT and GLYCOGEN
Fat intake must be monitored and can cause obesity.
1. It is also important for protecting vital organs2. It is crucial for cell production3. Control of heat loss
3% of your diet should be fatty foods
Protein
Protein is composed of hydrogen, oxygen and nitrogen and some have minerals.
Proteins are the ‘building blocks’ of our body and essential for repairing our body
They are necessary for the production of: Enzymes Haemoglobin Hormones
They can be used for energy, but only if there is no energy or carbo’s present.
Proteins (Pg 87)
Examples of proteins:
Micronutrients
There are a number of micronutrients the body needs:VitaminsMineralsVitaminsNeeded in small quantitiesVery important as they;
Help us get energy Functioning of our metabolism Prevent disease
Our body cannot, naturally produce vitamins except for Vit D
The main source of vitamins are fresh fruit and vegetables
Micronutrients
MineralsTwo types:
Macro-minerals (needed in large amounts) – Calcium, Potassium and Sodium
Trace elements (needed in small amounts) – Iron, Zinc and Magnesium
You will loose some minerals through sweating, so if you do lots of exercise, you should replace these minerals
You need to know more detail about Iron and Calcium
Iron – Essential component for haemoglobin (oxygen delivery). So an iron deficiency will be detrimental for an endurance athlete. Main source – Red meat
Calcium – Essential for bones and teeth. So a calcium deficiency may lead to osteoporosis and bone fractures. Main source – Dairy products and Nuts
Water
This is also essential especially people who do sport It carries nutrients around the bodyRemoves waste productsRegulates body temperature
Water is lost through sweat and urine. Obviously the activity intensity and duration affect how much
Daily consumption should be 2 litres approxWhen exercising, more should be drunk to keep
hydrated
Not enough water
When you don’t get enough water;Your body won’t be able to exerciseThe CV system will become inefficient with no waterAn inadequate blood supply to muscles and skin –
which will lead to heat exhaustion
You must drink water during exercise to minimise dehydration and slow the rise in temperature
Not enough water
When you don’t get enough water;Your body won’t be able to exerciseThe CV system will become inefficient with no waterAn inadequate blood supply to muscles and skin –
which will lead to heat exhaustion
You must drink water during exercise to minimise dehydration and slow the rise in temperature
Practical Implications
Make notes on the Practical Implications on Pg 89
Fibre
Two types of fibre: Soluble Insoluble
It is not digested when we eat it, so has no calorie benefit. It is only found in the cell walls of plants. So meat, fish and
dairy have noneEssential for healthy bowel function – Fibre absorbs water
as it passes through the intestines, making waste products softer and moves through the system easier
It reduces many bowel problems:ConstipationHaemorrhoids (Piles)Cancer (in the colon (small intestine) and large intestine)We should be eating 18g of fibre a day, most only eat 12g a
day
Having a healthy diet
We should be eating the following proportions:50% Carbohydrates30-35% Fat15-20% Protein
Consider the following when planning your diet
Pg 90
Nutrition Pyramid
Having a healthy diet
Having the right balance in your diet is the most important aspect for health and fitness
So it doesn't mean eating food that doesn't taste nice, but having the right balance of all foods
What night affect what you eat? (Pg 91)12345
Having a healthy diet
Eating enough fruit and veg is vital How many per day?5 portions (a rough guide) (Pg 91 – what is a portion?)
Don't eat to much salt – Why? It can cause high blood pressure
Guidelines on having a healthy diet + lifestyle
Use Pg 91/92
Eating enough or too much?
You need to balance what you take in and what you use, (what you eat and what you use as energy)
This is sometimes called the body’s METABOLISM.The BASAL METABOLIC RATE is the amount of energy
the body uses at rest (keep our heart, lungs etc... working)
So working out how much we need, we need to add our Basal Metabolic Rate to any other energy we use to do sport and do our daily living.
Energy is used in kilocalories and kilojoules (1KCal = 4.2KJ)
Men can consume 2,800-3,000KCal a day and women 2,000 – 2,200KCal, without putting on weight.
HOWEVER...Metabolic rates differ and it gets slower as you get older.
Factors affecting Energy Expenditure
Frequency of exercise Intensity of exerciseType of exercise and the durationAge, gender and body composition of the individualFuels available (food available)When you exercise the energy used needs to be
replaced, so some strategies to use if you regularly do exercise:
Glycogen Stores
Ensure the body has enough Glycogen.So some athletes Glycogen load or (Carbo-Loading)For three days they will only eat protein and fat with light
training, so depleting the stores in the body.Three days before the competition, they will only eat
Carbohydrates e.g. Pasta, bread, rice and fruitThis will fill the stores up to the maximum and allow the
person to have a high store of glycogen for the competition
Glycogen Stores
Other strategies to do with your Glycogen store are: (Pg92)
Fluids
You can loose up to 1litre of water in 1 hour of endurance exercise.
So rehydration is essential, even if you don’t feel thirsty
See Practical Applications Pg 93
Vitamins and Minerals Supplements
More exercise means your body needs more vitamins and minerals
If you eat more, to keep your energy levels up, then you will automatically be getting more of these, but it may be beneficial to take some supplements
Sports Performers and Nutrition
What factors should a performer take into account when planning their nutritional intake? (Pg 93)
Planning your Diet
When planning your diet for the future you should consider: (Pg 94)
FLASHCARDS
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