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Sources of Vitamin D

The main food sources of Vitamin D will be revealed here.

There are several forms of Vitamin D – vitamin D3 (the main form) will be discussed here, and will be referred to as vitamin D. Vitamin D is produced in the liver and kidneys following the skin’s absorption of sunlight.

Its major function is to increase the absorption of calcium and phosphate from the intestine, thus enhancing bone formation. It also reduces excessive cell division and can regulate the immune system. Small amounts of vitamin D are present in eggs, butter, and fatty fish.

It has long been thought that people who receive adequate sunlight are not at risk of Vitamin D deficiency. However, it has recently been found that a significant proportion of the population may be deficient in Vitamin D. Particular at-risk groups include infants living in cold environments with minimal exposure of the skin to sunlight, institutionalised people (e.g.

in nursing homes), or those required to cover up with clothing for religious or race-related reasons, hence they may need supplementation.

A deficiency of vitamin D may also occur when there is a problem of the liver or kidney, so vitamin D cannot be made. Deficiency can result in rickets in children, and osteomalacia, or bone thinning in adults.

Food Source	Vitamin D (ug/100g)	Notes	RDI
High
Cod Liver Oil	210	Maximum of 40% loss in cooking. Stable to heat, aging and storage.	Infants and young children: 400 I.U (International Units). No normal recommended intake is given for adults as they seem to gain adequate from normal exposure to sunlight.
Medium
Fatty Fish	5 – 25
Margarine	8
Low
Egg yolk	5
Butter	1
Cheese	0.2
Milk	0.01

Source: Walqvist, Food and Nutrition.

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Food High in Calcium

Food high in Calcium will provide the vital mineral for good bone health. The body has more than 99% of calcium in the bones. Calcium is also necessary for blood clotting, muscle and nerve function.

Calcium and phosphate metabolism are controlled by parathyroid hormone (PTH), calcitonin and vitamin D. Plasma calcium concentration is highly controlled within the body. It is essential that calcium intake is adequate otherwise PTH takes calcium from the skeleton. It would be replaced once dietary intake is abundant.

The skeleton is constantly being transformed, that is bone deposition and bone resorption are ongoing. Bone loss occurs when bone resorption exceeds formation.

If you eat food high in calcium and therefore calcium intake is sufficient, calcium bone density increases. This will peak at about 20-25 years of age, and gradually decline later in life. The peak bone mass that is reached is a good indicator to the chance of osteoporosis later in life. The better the peak reached, the less chance of developing osteoporosis.

The RDI for calcium changes by age and gender.

How much Calcium do You Need?

	Age or stage of life	Recommended calcium intake (milligrams)
Women		800
	After menopause	1000
	During pregnancy	1100
	During lactation	1300
Men		800
Infants	Up to 6 months	300-500
Children	1-7 years	800
Girls	8-11 years	900
	12-15 years	1000
	16-18 years	800
Boys	8-11 years	800
	12-15 years	1200
	16-18 years	1000

”Eating for Peak Performance” – Rosemary Stanton 2nd Edition p.122

Food High in Calcium

Milk & Soy Foods – Calcium (mg) per 250ml
Skim milk	375
Calcium fortified	500
Dairy Wise	300
Hilo milk	310
Whole milk	275
Flavoured milks	300
Sustagen 250ml	400
Sustagen Sport 200ml with water	400
So Good	290
So Good Lite	290
Tofu, firm (calcium coagulant) 100g	160
Tofu, soft (calcium coagulant) 100g	80
Yoghurt – Calcium (mg) per 100g
Plain, natural	290
Low fat, natural	360
Whole, fruit flavour	260
Low fat, fruit flavour	320
Cheese – Calcium (mg) per 30g
Cheddar	240
Edam	260
Processed	200
Camembert, Brie	150
Ricotta	100
Cottage	30
Dairy Desserts
Ski Double Up 200g	245
Fruche, low fat 200g	160
Ice cream 1 scoop	65
Custard 100ml	150
Other foods – Calcium per serve
Almonds 30g	70
Brazil nuts 30g	55
Peanuts 30g	20
Peanut butter 1 Tbsp	10
Sardines & bones 50g	175
Salmon & bones 50g	150
Prawns 100g	150
Meat, chicken 100g	20
Baked beans 1 cup	90
Kidney beans, chick peas ½ cup	60
Soy beans ½ cup	80
Tahini 1 Tbsp	90
Sesame seeds 3 Tbsp 30g	40
Broccoli 1 cup cooked	30
Bread 1 slice	20
Pasta 1 cup	10
Rice 1 cup	5
Egg	35
Milk chocolate 50g	125
Dark chocolate 50g	25
Fresh fruit average	20
Fruit juice 250ml	25

Glenn Cardwell – Gold Medal Nutrition, Second Edition 1999 p.78

The best food high in calcium are dairy products. They are not only the richest source of calcium, but they also help increase the absorption of calcium due to their lactose content. The average Westerner consumes about 70% of their calcium from dairy foods

Osteoporosis is one of the more serious side effects of calcium deficiency. If you require a calcium supplement, then it is best to have one containing vitamin D as it helps to increase calcium absorption from the intestine (e.g. Caltrate with vitamin D).

In Australia, statistics show that about 1/3 males and nearly half of females over 60 years of age have some type of osteoporosis. Symptoms include stooped posture, hip fractures or brittle bones.

Osteoporosis is defined as bone density 2.5 or more standard deviations below the age-matched mean. Osteopaenia, or sports osteopaenia as it is more commonly known, is classified as bone density levels 1 – 2.5 standard deviations below the mean.

Groups at Risk of Calcium Deficiency

Vegans
Diets high in salt, protein, alcohol or caffeine (as these increase calcium excretion in the urine)
Eating disorder sufferers
Low energy, restricted, and fad dietersRisk Factors for Osteoporosis
Osteoporosis is the total decrease in bone mass. This leads to issues such as bone fractures, particularly of the wrist, spine and hip. Osteoporosis has many risk factors, which are divided into two categories: non-modifiable and modifiable. It is best to focus on the modifiable factors, as these can be changed to help decrease the chance of osteoporosis.

Non-modifiable Risk Factors of Osteoporosis
Caucasian and Asian women who are small boned
Female gender
Age
Family history of osteoporosisModifiable Risk Factors of Osteoporosis
High protein intake
High caffeine intake
Smoking
Alcohol intake
Prolonged bedrest (can lead to bone loss)
Absence of gravity (e.g. astronauts) can lead to bone lossAll of the above factors contribute to a reduction in calcium absorption

Positive modifiable factors include:
Eat food high in calcium: in particular for pregnancy, breastfeeding, post-menopause, adolescents and amenorrhoeic athletes
weight lifting or weight bearing exercise; greater physical stress and compression on a bone leads to greater size and strength.Snacks to increase Calcium Intake
Increasing your calcium intake doesn’t need to be difficult. It also doesn’t have to mean drinking truckloads of milk! Here are some other suggestions for increasing your calcium intake:
Soup made with skim milk
Evaporated skim milk in curries
Wholegrain cereal and skim milk
Fruit salad and low fat milk
Sardines on toast
Vegetable stir fry with tofu
Low fat smoothies
Milk based coffee

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Healthy Weight Loss

Healthy Weight Loss can happen for all of us if we know what caused the weight gain in the first place. Excess body weight is made up of unused energy. A pound of body fat (0.45kg) represents approximately 3500 calories of stored energy (unused calories). In order to shed a pound of fat, you have to burn 3500 more calories than you consume.

This may seem like a simple formula, so why do we still have a weight problem? You must remember that your body is a thinking and living organism that is designed to protect itself. If you tried to reduce your calorie consumption by the entire 3500 calories in one day, your body would register some type of alarm and think that there was a state of emergency. Your metabolism would immediately slow down, go into fasting mode and no healthy weight loss would be achieved. This would also be the case if you thought that consuming all your required calories by means of a burger for breakfast and then eating nothing else for the rest of the day would solve your problem.

It is far more beneficial to spread your weight loss out over a period of a week. This way you should aim to reduce your caloric intake by 3500 to 7000 calories per week which would result in weight loss of one to two pounds per week. Generally, you shouldn’t try to lose more than two pounds (approx 1 kg) in a week. Doing so may cause health risks and you are unlikely to be successful as you would have to modify your diet so much that you would struggle to maintain it.

Assuming you were attempting to lose two pounds per week, you can use a basic method of calorie counting to help you accomplish your goal. Firstly, you need to figure out how many calories a person of your age, sex, and weight usually needs in a day, subtract 500 from that amount, and follow a diet that provides you with that many calories. For example, if you would normally need 3000 calories in a day to function properly and maintain your current weight then you would need to follow a 2500-calorie a day diet in order to achieve healthy weight loss. Secondly, figure out how much exercise a person of your weight would need to do to burn 500 calories per day, and do an exercise plan that will help you achieve your goal. The result is simple: 500 fewer calories consumed and 500 more calories burnt equals a 1000 calorie per day shortfall, which, over the course of a week adds up to 7000 calories, or two pounds. Although individual results may vary, the bottom line is if your body is consuming fewer calories than it needs, then healthy weight loss will be lost.

How to Calculate your needs

You actually need to determine how many calories you really need on a daily basis if you plan on trying to eat fewer calories than your body requires. Adults can work out their approximate energy needs using the following formula:

A. Current Body weight multiplied by 12 (for men) or 11 (for women)Example for males: 150 lbs. x 12 = 1800

B. Activity Level – One third body weight multiplied by the number of hours you don’t sleep, (typically 16 hours) e.g. 150 lbs. x 1/3 = 50 x 16 = 800 Calories.Required Calories = A + B = 1800 + 800 = 2600 calories per day

So we can determine that a 150-pound man requires approximately 2600 calories per day based on an inactive lifestyle.

The “Basal Metabolic Rate” is the number of calories a man of that weight would burn just to function properly, i.e. keep the heart beating, the lungs pumping, etc. You would only burn your basal metabolic rate worth of calories if you slept all day. This means the “Activity” calculation is approximately the amount of calories a person would burn by spending his or her whole day sitting around. If you participate in activities other than sitting all day, you can increase your “activity hours” by the number of hours you are actually active.

Adult females can calculate their approximate calorie needs using the same formula, except that the “Basal Metabolic Rate” is determined by multiplying body weight by 11 instead of 12.

Children and teenagers require more calories by body weight, but the amount varies by age and by individual child. It is best to consult a physician before altering a child’s calorie intake, however increasing activity and exercise in children won’t hurt them, especially in today’s society, as it can help control obesity and improve other areas of their balance and coordination.

Hopefully, the above explanation gives you a general idea of how understanding calories relates to healthy weight loss and weight gain. Of course this is

not a complete diet plan, however understanding your body’s calorie needs is a definite prerequisite to making the changes necessary to conquer obesity.

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Water!

Water would be considered the most important nutrient of all. Naturally so, considering the average adult male has 60% water content and about 51% in females. Males have higher water content than males due to their greater muscle mass, which stores water.

Water is vital for many physiological and biochemical processes within the body.

Drinking fluids contribute to about 60% of the daily water requirement. 30% comes from the consumption of solids and 10% is the result of oxidative processes in cells.

Water needs to be constantly replenished through the diet as we lose approximately 2.5litres of water daily. Water is lost through the urine and faeces, perspiration from the skin and evaporation from the lungs. When

fluid loss is equal to the fluid consumed, it is considered a state of water balance.

Most Westerners do not consume the daily recommendation of 6-8 glasses (2 litres) of water. We can cope with mild losses of water, but extreme losses of water and low intake can lead to dehydration. Chronic dehydration can be lethal.

Location of water in the tissues of adult males

	g/kg body weight	% total body weight
Blood plasma	41	7
Interstitial lymph	121	20
Dense connective tissue and cartilage	41	7 Bone Water417Transcellular water152.5Intraluminal gut water8.41.4Total extracellular water26043Total intracellular water34047Total body water600100

Source:Wahlqvist, Food and Nutrition, p.256

Hourly water loss at rest and during exercise of a 70kg individual

	Water lost at rest ml per hour	Water lost at rest % total	Water lost during exercise ml per hour	Water lost during exercise % total
Skin	15	16	15	1
Lungs	15	16	100	7
Urine	58	63	10	1
Perspiration	4	4	1200	91
Total	92	100	1325	100

Wahlqvist, Food and Nutrition, p.258

Daily output of electrolytes in perspiration and urine for an average adult person at rest

Fluid	24 hour volume	Na+ (mg excreted in 24 hours)	Cl- (mg excreted in 24 hours)	K+ (mg excreted in 24 hours)
Perspiration	100ml	115	144	20
Urine	1400ml	3500	5400	2700

Wahlqvist, Food and Nutrition, p.258

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Vitamins!

Small concentrations of vitamins can be found in foods. Each vitamin has a particular and unique role to play within the body. Vitamins are essential within the diet as the human body is not able to synethesise most vitamins (except vitamins D and K. Some foods contain precursors or provitamins of specific vitamins – that is, they need to be converted by the body into the active vitamin before they can exhibit the characteristic functions.

Vitamins are divided into two categories:

Fat Soluble and
Water Soluble.

Vitamin D, Vitamin A, Vitamin E and Vitamin K are fat soluble – that is, they are carried on fats in the body, and stored in adipose tissue (fat cells) and the liver. If a person has a condition restricting fat absorption, then it will also reduce absorption of fat soluble vitamins. As these vitamins can be stored in the body, deficiencies can be slow to develop. On the other hand, risk of toxicity from these vitamins is also greater.

The B group vitamins along with Vitamin C, are water soluble. They can be flushed through the body, and are unable to be stored. The potency of the vitamins can be lost when foods with these vitamins are boiled or soaked.

The human body doesn’t gain energy directly from Vitamins. Vitamins assist the mechanisms of the body to produce energy. Most Western diets contain enough vitamins, so supplementation is rarely required. If vitamins are lost through poor food storage and preparation then supplements may be required to replace those deficiencies. Also, if there is a low level or poor absorption of vitamins in food, or higher rate of utilisation of the vitamins, then vitamin intake may not be optimal.

Vitamin A

Vitamin A is a fat soluble vitamin, meaning the body can store it within the fat cells. The functions of Vitamin A are to assist in bone growth, vision and the formation of cells on the surface of the skin and the lining of the gut. There are two dietary forms of Vitamin A:

one form, known as retinol and
second form, B-carotene (pro-Vitamin A).

Retinol is found in animal sources including full cream dairy products, eggs, margarine, butter and liver.

B-carotene is converted into vitamin A within the intestine. You will find B-carotene in deep yellow, orange and green fruit and vegetables. This form also has great antioxidant properties.

Vitamin A has a recommended daily intake (RDI) of 750ug retinol equivalents/day for men and women. Each 1ug of B-carotene is equivalent to the biological activity of 1/6ug retinol, however the absorption of B-carotene may further lower this amount. (The RDI for vitamin A is measured in retinol equivalents because this then takes into account sources from both forms of vitamin A.)

Vitamin A deficiencies can lead to blindness, stunted growth, reduced appetite, and decreased immunity. Most Western diets contain adequate levels of Vitamin A and therefore deficiencies are rare. Excessive quantities of the retinol form of vitamin A can be stored in the liver and have toxic side effects. These side effects include nausea, vomiting, lethargy, dry skin and loss of appetite. An over-consumption of B-carotene can cause orange pigmentation of the skin. If overdose of the retinol form are consumed during pregnancy, congenital abnormalities can result in the foetus.

Food Sources of Vitamin A

Food Source	Retinol (ug/100g)	Carotene (ug/100g)	Notes	RDI
High
Cod Liver Oil	28,400	1050	Maximum of 30-40% loss in cooking. Both retinol and carotene are sensitive to light and oxygen	Adults over 11 yrs – 750ug
Palm Oil	0	7000
Fried lambs Liver	20,600	10
Medium
Carrots	0	2000
Spinach	0	1000
Sweet Potato	0	670
Egg Yolk	660	100
Low
Bread	0	0
Potato	0	Trace
Chicken	Trace	Trace

Note: mg=1/1000 of a gram
ug=1/1000 of a mg

Vitamin D

A deficiency of vitamin D may also occur when there is a problem of the liver or kidney, so vitamin D cannot be made.

Deficiency can result in rickets in children, and osteomalacia, or bone thinning in adults.

Food Source	Vitamin D (ug/100g)	Notes	RDI
High
Cod Liver Oil	210	Maximum of 40% loss in cooking. Stable to heat, aging and storage.	Infants and young children: 400 I.U (International Units). No normal recommended intake is given for adults as they seem to gain adequate from normal exposure to sunlight.
Medium
Fatty Fish	5 – 25
Margarine	8
Low
Egg yolk	5
Butter	1
Cheese	0.2
Milk	0.01

Source: Walqvist, Food and Nutrition.

Vitamin E

Like many of the other vitamins, Vitamin E, has several different forms known as tocopherols. The a-tocopherol form is the most important form.

Minor benefits of vitamin E are in nerves and muscle function. The main benefit of vitamin E is its antioxidant properties. It can help to prevent oxidative damage to the arteries near the heart (a major cause of atherosclerosis). Polyunsaturated fats can be converted by oxygen into free radicals, so the greater the intake of these fats, the more vitamin E is required.

Foods containing vitamin E include wheat germ, peanuts and olives, as well as polyunsaturated margarine. Grains, seeds, nuts, fish and dairy products also have good amounts of vitamin E. The RDI for adults is 7 – 10mg/day.

Symptoms of deficiency can include nerve cell and muscle fibre problems, as well as excess red blood cell breakdown. However, many of the polyunsaturated fat sources contain Vitamin E, so deficiencies are rare. Megadoses of vitamin E can lead to weakness, fatigue and dermatitis.

Food Source	Vitamin E (mg/100g)	Notes	RDI
High
Wheat germ oil	140	Maximum 55% loss in cooking, sensitive to heat and oxygen and decomposes in sunlight	8 yrs and over – 7-10mg/day
Polyunsaturated vegetable oil	20-80
Medium
Peanut oil	15-20
Olive oil	5
Nuts, seeds, whole grains	1-20
Low
Milk	0.02

Source: Walqvist, Food and Nutrition

Vitamin K

Vitamin K foods have great benefits. The most important role of vitamin K is blood clotting. This helps to prevent excessive bleeding.

Approximately half the body’s requirement for vitamin K is synthesised by bacteria in the intestine, however substances which destroy bacteria (e.g. antibiotics) can increase vitamin K requirements. The remainder can be obtained from sources including green leafy vegetables, carrots, soy beans and wheat bran.

There is no RDI for vitamin K, considering the amount synthesised in the intestine varies. Deficiencies are rare, and will result in haemorrhage. Newborns are usually given a dose of vitamin K due to low body stores and lack of bacteria in the intestine. They then receive vitamin K via breast milk, allowing time to increase their stores and synthesise bacteria.

Vitamin K is a fat soluble vitamin.

Food Source	Vitamin K (ug/100g	Notes	RDI
High
Spinach	240	Maximum of 5% cooking loss. Sensitive to light, oxygen and both acid and alkali conditions	U.S.A. 70-140ug/day for men and women
Soy beans	190
Cabbage	100
Medium
Bran (wheat)	80
Green beans	20
Pork liver	20
Low
Oranges and apples	Less than 5

Source: Walqvist, Food and Nutrition

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Foods containing Protein

There are many foods containing proteins. Below is a comprehensive list of these foods.

What are proteins? Each particular protein is characterised by a group of amino acids arranged in a special sequence.

There are many sequence combinations and many different proteins as there are 20 major different types of amino acids. Each protein has a different role in the body. Eight of the amino acids (nine for children) are considered “essential” or “indispensable” amino acids, as the body can’t make them. These amino acids must be consumed from the diet. The body can produce the other twelve amino acids and are therefore classified as “non-essential” or “dispensable”.

Indispensable Amino Acids:

Histidine (in children)
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Valine

Dispensable Amino Acids

Alanine
Arginine
Asparagine
Aspartic acid
Glutamic acid
Cysteine
Glutamine
Glycine
Proline
Serine
Tyrosine

When protein is digested, it is broken down into amino acids and incorporated into new proteins in the liver. Protein synthesis can only occur when all required amino acids are present. This means the essential amino acids become the restricting factor.

Most Westerners consume enough protein within their diet, therefore supplements are not required. Excess dietary protein is used as energy when Carbohydrate intake is low or is stored as fat (especially when from a high fat source).

Another side effect from a high protein diet is that calcium absorption and retention is reduced. This is due to the kidneys working harder to excrete the extra nitrogen.

Major Functions of Protein in the Body

Protein is a necessary part of all body cells. Most people realize that protein is found in muscles, however few recognize it is also found in the kidney, heart and liver, in skin, hair, nails, bone and teeth. Protein is always needed in larger quantities during times of growth, especially during times of childhood, adolescence, and pregnancy.

Protein is also needed for fluid balance, blood clotting, hormone and enzyme production, and immune function. The body constantly breaks down proteins and recreates new ones. Requirement is 3.5 – 4.5g/kg/day (200-300g/day). Dietary intake needs to account for about 1/3 of this, and the remaining protein synthesis comes from recycled amino acids.

Complete protein foods are those that contain all essential amino acids. These are mainly animal based products, with the exception of soy beans:

Low fat dairy products
Fish and seafood
Beef, lamb, veal, pork
Skinless poultry
Eggs
Soybeans

For people following a balanced diet, these foods containing proteins provide about 2/3 of daily protein intake.

“Incomplete proteins” come from foods lacking one or more of the essential amino acids. These tend to make up 1/3 of dietary protein intake. Examples of these foods include:

Legumes
Nuts
Seeds
Cereals
Bread

Therefore, it is unlikely that meat eaters would consume a diet deficient in amino acids. Lacto-ovo vegetarians (consume no meat, chicken or fish, but do eat dairy products and eggs) and in particular vegans (no meat, chicken or fish, dairy products, or eggs) need to ensure a wide variety of the above listed foods are eaten to obtain all essential amino acids.

How much protein is in Foods

MEAT AND ALTERNATIVES

Each of the following foods containing protein has 6g protein.

20g	Meat cooked
20g	Poultry (chicken, turkey, duck, etc.) cooked
30g	Fish cooked or tinned
25g	Shellfish cooked
25g	Offal (liver, tripe, kidney, brains, etc.) cooked
50g	Soft cheese (ricotta, cottage, cream cheese, etc.)
1	Egg (55g)
40g	Nuts
25g	Peanuts
90g	Legumes (dried beans and lentils) cooked

MILK PRODUCTS
Each of the following foods containing protein has 3g protein.

100ml

Whole milk

75ml

“Rev” or “Skinny” milk

50ml

“Physical” milk

100ml

Soy milk (full or light)

4 Tbsp

Custard (from powder and whole milk)

3 Tbsp

Custard (from egg and whole milk)

1 scoop

Ice cream (average)

50g

Natural yoghurt (full cream)

40g

Natural yoghurt (low fat)

70g

Fruit yoghurt (full cream)

50g

Fruit yoghurt (low fat)

CEREALS AND GRAIN FOODS

Each of the following contains 3g of protein

BREADS
1 slice	bread
1/2 average	muffin
1 small	Scone
1 average	Crumpet
1/2 average	Bread roll
1/2 average	Croissant
BISCUITS
4	“Thin Captains”
4	“Sao”
4	“Low Salt Vitaweets”
4	Crispbreads
3	Rice Cakes
3	“Teddy Bears”
4	Cream biscuits
PASTRY
2 sheets	Filo
6cm slice	Pie (not including filling)
1	Party pie (not including filling)
CAKES
5cm slice	Sponge cake
1 slice	Plain cake
1	doughnut
BREAKFAST CEREALS
3	“Weet-Bix
2 Tbsp	Muesli
1 medium bowl	“Weeties”
200g	Porridge (cooked with water)
OTHER
60g	Dry Rolled Oats
2/3 cup	Cooked rice (120g)
1 large	Cooked Potato (120g)
1/2 cup	Cooked Pasta (75g)
30g	Plain Flour

The recommended daily intake of protein for an adult is 0.75 – 1g/kg/day. The average Westerner already consumes more than this recommendation. The figures show that a 65kg female consuming 120g cooked meat or chicken (very small serve!), 200g of yoghurt, 200ml reduced fat milk, and 4 slices of bread daily would consume at least 66 grams of protein daily.

There would also be extra protein absorbed from other foods.

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Ideal Body Fat for Athletes

In order for an athlete to maintain their ideal body fat and weight range we need to consider many factors.

Fat plays an important role in the body by providing an excellent energy source and supplying essential vitamins only found in fat. It is also an important site for sex hormone production and nervous cell development. Fats are referred to as triglycerides and they are made up of a glycerol molecule with three fatty acid molecules attached to it.

Fats are classified according to their saturation. This refers to the number of hydrogen atoms present in the fatty acid and determines their state at room temperature. Saturated fatty acids are solid at room temperature and have no double bonds. Monounsaturated fatty acids have one double bond and polyunsaturated fatty acids have more than one double bond. These are liquid at room temperature and are less stable. The length of the fatty acid chain determines how quickly it is absorbed, shorter chain length are absorbed quicker.

Maintaining Ideal Body Fat Levels

The majority of the population seem to believe that athletes would never struggle with ideal body fat levels or weight issues as they look fit and healthy. But like every body else, if athletes consume a diet too high in fat will not only be inadequate in carbohydrate, it will also prevent the maintenance of ideal body fat levels.

Excess body fat is caused by excess dietary fat. Extra body fat in athletes is “dead weight” to carry around. Athletes find that their power to weight ratio is improved with ideal body fat levels. Greater power to weight ratio allows for skilled movements in a confined space (e.g. divers and gymnasts).

Road cyclists, distance runners and triathletes also benefit from ideal body fat levels because any excess body fat will have to be carried over long distances. Sometimes it is the aesthetics of a sport that requires athletes to have low body fat levels (e.g. ballet). Higher body fat levels may be less of an issue for contact sports, skill-based sports, and some strength sports.

When determining an ideal body fat and weight range for athletes, it is important to consider the ranges in context. That is, body fat levels are specific to the sport, specific to the individual (e.g. genetics, age, gender, health, lack of injuries, past weight history, menstrual history), and related to performance history (i.e. knowing they run better at a certain body fat level).

Causes of Excess Body Fat

Many factors need to be considered when determining ideal body fat levels. These include:

Genetic factors play a 25 – 40% role in adiposity. Genes also contribute to choice of dietary intake
Environmental factors involves issues including energy intake and macronutrient selection. Look at the effect of exercise on appetite and the level of incidental activity (e.g. using the remote control for the television versus moving from the chair to adjust the television)
Total fat and energy intake
Energy cost of daily living. Inactive people use less energy than those more active (i.e. some athletes train, then come home and sleep or watch television, whilst others may remain more active and go to work or uni)
Social factors: athletes eating in a dining hall tend to overeat, due to the smorgasbord available
Psychological factors including non-hungry, boredom, and depression eating can all increase body weight and fat levels
Physiological factors including certain hormones, medications and disease conditions can influence body fat levels
In order for an athlete to decrease body fat, they need to take responsibility for their food intake. They may need to decrease intake of dietary fats (particularly saturated fats), decrease intake of alcohol, and reduce overall quantity of food ingested when in the off-season or suffering from a chronic injury.

Helping Athletes to Lose Weight

It is best to seek advice from a sports nutritionist when an athlete is required to lose weight and/or body fat. This is to ensure adequate intake of all nutrients during the weight loss period.

An assessment of appropriate total levels of body fat loss would be made. Behaviour modification has been found to be essential if weight loss is to be maintained long term, and gradual loss of weight is desirable. Extreme measures of weight loss should be discouraged.

Long term and short term goals can be used with the athlete. These goals shouldn’t be just weight based. Regular review visits are necessary to keep the athlete monitored and motivated.

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Protein for Sports – Will I bulk up?

Daily protein requirement for athletes is one of the more controversial areas of sports nutrition. The issue relates specifically to whether athletes have an increased need for protein compared to sedentary individuals.

Muscle tissue is made from protein, so it is thought that if an athlete consumes a greater amount of protein then they will have greater muscle size and development! Some body builders have been known to consume whole chickens, and eggs by the dozen in an attempt to enhance muscular growth!

According to the IOC, Consensus Conference on Foods, Nutrition and Sports Performance, “Protein requirements are higher in individuals involved in physical training programs than inactive people. However, most athletes already consume sufficient protein as a consequence of their increased energy intakes.” That is, athletes already have an increased energy intake overall, hence their intake of protein will also be increased.

Dietary protein provides the amino acids that are essential to build and repair tissue in the body. There are eight essential amino acids that need to be provided through the diet and twelve non-essential amino acids that the body can produce itself. Animal food sources are classified as complete protein because they provide all the essential and non essential amino acids. Plant food sources are classified as incomplete protein because they do provide some but not all amino acids.

Daily Protein Requirement for Athletes

The following table shows the different levels of daily protein requirements for different groups of athletes.

Sedentary adult population0.8 – 1.0g/kg

Recreational athletes1.0 – 1.2g/kg

Endurance athletes1.2 – 1.6g/kg

Football / power sports1.4 – 1.7g/kg

Resistance athletes1.5 – 1.7g/kg (early training) 1.0 – 1.2g.kg (steady state)

Female athletesapprox 15% less than male athletes (due to females being able to spare glycogen more effectively when exercising)

Adolescent athletes (growth spurt)2g/kg

Male athletes consume 1.5 – 4.0g/kg whereas female athletes consume an average of 1.0 – 2.8g/kg.

This shows more than enough protein is being consumed in most cases. Very few athletes consume inadequate levels of protein. Vegans and vegetarians may not consume enough protein if they don’t eat adequate vegetarian alternatives. Some athletes (particularly female) attempting to decrease body weight may also be at risk of not consuming adequate protein.

Why is the Daily Protein Requirement Higher for Athletes?

The daily protein requirement for athletes is higher because protein is used to enhance muscle growth and bulk, and assist the repair of muscle damage. This is especially important in strength based sports. Most of the protein accretion occurs within the first few months of weights training. During this period, the protein required is much greater than that required later.

Protein requirements are also higher because it is used as a fuel in small amounts. This is especially in high intensity training or endurance training of greater than 1 hour, or earlier if muscle glycogen stores are low. The liver and kidneys can synthesise glucose from amino acids (gluconeogenesis). However, consuming more protein than is recommended will not enhance these processes. Extra protein consumed will be merely oxidised and used for energy

Amino Acid Supplements

Although most athletes consume more protein than they require, some still believe that extra protein (or amino acids) will enhance their performance.”Claims related to these supplements include:

Improve performance, recovery, power, endurance and energy
Increase muscle bulk
Assist weight loss AND weight gain
Delay fatigue, suppress appetite, control depression
Stimulate growth hormone release”
(Source: Gold Medal Nutrition, Second Edition, Cardwell, 1999)

There is little scientific evidence supporting the supplement’s benefits in athletes with sufficient protein consumption. It is also important to know that protein is absorbed much more effectively as peptides (i.e. small proteins) rather than as free amino acids. Free amino acids can cause diarrhoea and abdominal pain if consumed excessively.

Branched Chain Amino Acids

Three indispensable amino acids are classified as branched chain due to their chemical structure:

leucine
isoleucine
valine

During exercise, these branched chain amino acids are oxidised in preference to other amino acids. Therefore the theory was suggested that if branched chain amino acids were supplemented in the diet, athletes would be able to exercise longer before fatiguing. This may be true, however, if adequate carbohydrate is stored in the body and fed during exercise, there will only be a small amount of branched chain amino acids oxidised, hence fatigue will be delayed anyway.

Possible Risks of High Protein Intake These include:

atherogenesis (development of plaque in the arteries near the heart)
possible impaired kidney function (unlikely unless pre-existing kidney disease)
accelerated calcium loss
dehydration (due to excess nitrogen excreted by the kidneys).

Bulking Up

It should be understood that an extremely high protein intake is not the way to increase muscle bulk! Bulking up requires three factors:

positive energy balance (i.e. a greater energy intake than energy expenditure)
suitable and specific hypertrophy weights program to stimulate muscular growth
genetics (i.e. the right parents!!) So from a nutritional point of view, this translates to a high carbohydrate intake to meet energy requirements. Adequate glycogen stores are a must, otherwise body protein will be utilised for energy. There is also need for an adequate protein intake, to ensure muscles continue to repair and grow following exercise. The diet should also include adequate micronutrients for the growth of new tissues (e.g. zinc and iron).

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Complex Carbohydrates for Sports

Below is a list of complex carbohydrates, but first we need to discuss why they are important.

There are many factors that influence the quantity and type of fuels within an athlete’s nutrition plan that are utilised when exercising. The two large determining factors include the intensity and duration of exercise.

In general, the higher the intensity of exercise, the more carbohydrate is used as a percentage of total energy. If an athlete was to eat foods that are high on the list of complex

carbohydrates, glucose is transported to the muscles and stored as glycogen.

Glycogen is also stored in the liver. Active people will have more glycogen stores than sedentary people. It is these stores that are used during exercise. The longer the duration of exercise, the more the body relies on fat and some amounts of protein. (The liver converts protein to glucose through a process called gluconeogensis.)

The breakdown of food such as glucose produces adenosine triphosphate (ATP), which is then used for energy production.

Why a high Carbohydrate diet?

Carbohydrates are classed either as sugars or starches. Sugars are simple carbohydrates and are called monosaccharides or disaccharides (made from glucose molecules joined together). Starches are commonly called complex carbohydrates (see below for list of complex carbohydrates) and are called polysaccharides because they are made up of many glucose molecules.

When engaging in high intesity exercise, the rate at which fat is oxidised and mobilised is limited. This is why carbohydrate (CHO) is the preferred fuel for exercising muscle. It is quickly mobilised and the glucose is used to produce ATP. The CHO comes from both muscle and liver glycogen, as well as blood glucose.

An athlete weighing 70-75kg stores 100gm of glycogen in the liver, and 500gm in the muscle. If you consider that the same athlete may store 8-15kg of body fat, it is easy to see that CHO, not fat, may be limiting. Therefore it emphasises the importance of an athlete’s nutrition to be high in CHO.

Athlete’s requirement of CHO.

The amount of carbohydrate required within an athlete’s nutrition plan depends on the intensity of exercise undertaken.

4-5gm/kg body weight / day – walking, moderate exercise (3-5 hours /week).

5-7gm/kg body weight / day – moderate intensity exercise (1 hr/day), serious amateur athlete.

7-10gm/kg body weight / day – professional athlete. Maximises glycogen recovery; used for CHO loading.

List of Complex Carbohydrate Rich Foods

Achieving a diet that is ranked high on the list of complex carbohydrates will become easier if an athlete knows which foods to consume! It may be useful to know that an athlete needs 7gm CHO/kg, but it is important to be able to convert this into real food terms with quantities.

The following list of complex carbohydrate rich foods in 50gm serves of CHO:

Cereals
Wheat biscuit cereal (e.g. Vitabrits)	60gm (5 biscuits)
Light breakfast cereal (e.g Weeties, Cornflakes)	60gm (2 cups)
Muesli flake cereal (e.g. Sustain)	60gm (1-1.5 cups)
Toasted muesli	90gm (1 cup)
Porridge made with milk	350gm (1.3 cups)
Porridge made with water	550gm (2.5 cups)
Rolled oats	90gm (1 cup)
Muesli bar	2.5
Rice Cakes	6
Rice, boiled	180gm (1 cup)
Pasta or noodles, boiled	200gm (1.3 cups)
Canned spaghetti	440gm (large can)
Crispbread and dry biscuits	6 large (e.g Ryvita) or 15 small (e.g. Salada)
Fruit filled biscuits	5
Plain sweet biscuits	8 – 10
Cream filled/chocolate biscuits	6
Bread	110gm (4 slices white or 3 thick wholemeal)
Bread rolls	110gm (1 large or 2 medium)
Pita or Lebanese bread	100gm (2 pita)
Chapati	150gm (2.5)
English Muffin	150gm (2.5)
Crumpet	2.5
Cake Style Muffin	110gm (1 large or 2 medium)
Pancakes	150gm (2 medium)
Scones	125gm (3 medium)
Iced fruit bun	105gm (1.5)
Croissant	140gm (1.5 large or 2 medium)
Rice cream	330 gm (1.5 cups)
Fruit
Fruit crumble	1 cup
Fruit in heavy syrup	280gm (1.3 cups)
Fresh stewed or canned in light syrup	520gm (2 cups)
Fresh fruit salad	500gm (2.5 cups)
Bananas	2 medium – large
Mangoes, pears, grapefruit and other large fruit	2-3
Oranges, appples and other medium size fruit	3-4
Nectarines, apricots and other small fruit	12
Grapes	350gm (2 cups)
Melon	1000gm (6 cups)
Strawberries	1800gm (12 cups)
Sultanas and raisins	70gm (4 lbs)
Dried apricots	115gm (22 halves)
Vegetables and Legumes
Potatoes	350gm potato (one very large or 3 medium)
Sweet potato	350gm (2.5cups)
Corn	300gm (2 cobs)
Green beans	1800gm (14 cups)
Baked beans	440 gm (1 can)
Lentils	400gm (2 cups)
Soy beans and kidney beans	400gm (2 cups)
Tomato puree	1 litre (4 cups)
Pumpkin and peas	700gm (5 cups)
Dairy Products
Milk	1 litre
Flavoured milk	560ml
Custard	300gm (1.3 cups)
Diet yoghurt and natural yoghurt	800gm (4 tubs)
Flavoured yoghurt	350gm (2 tubs)
Icecream	250gm (10 tbsp)
Fromage Frais	400gm (2 tubs)
Sugars and Confectionary
Sugar	5gm
Jam	3 tbs
Syrups	4 tbs
Honey	3 tbs
Chocolate	80gm
Mars Bar and other 50-60gm bars	1.5 bars
Jubes and Jelly Babies	60gm
Mixed Dishes
Pizza	200gm (1/4 medium thick or 1/3 thin crust)
Hamburgers	1.3 Big Macs
Lasagne	400gm serve
Fried rice	200gm 1.3 cups
Sports Products and Drinks
Fruit Juice unsweetened	600ml
Fruit Juice sweetened	500ml
Cordial	800ml
Soft drinks and flavoured mineral water	500ml
Sports drinks	700ml
Carbohydrate loader supplement	250ml
Liquid meal replacement	250-300ml
Fruit smoothie250-300ml
Sports bar	1 – 1.5 bars
Sports gels	1.5 sachets
Glucose polymer powders	60gm

Howley and Burke, “Peak Performance.”

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Nutrition for Sport

When planning Nutrition for Sports, there are many nutritional goals that sports and fitness people need to meet. So we need to consider the following:

Do we meet the nutrient needs writing service that arise from strenuous exercise? This includes high carbohydrate, moderate protein, low fat diet with sufficient fluids.

Do we promote long term health? We need to consider not only the sports person’s current health but also future health. This means keeping saturated fat intake low, and ensuring sufficient calcium intake.

Can we achieve and maintain appropriate body mass and body fat levels in order to perform to the best of our ability? Nutrition for Sports needs to be low in fat.

Does our nutrition for sports plan promote recovery from training? This is particularly important for athletes who would train once or twice daily, ensuring they have enough energy to get through the next training session.

Does our nutrition for sports training mimick what we would do in competition? It is vital that good nutritional habits are practised through both training and competition times. There is no point starting an excellent nutrition for sports plan only at competition times. This is important to ascertain the sports person’s tolerance – both psychologically and physically.

Athlete Nutrition, what fuels are best?

An athlete’s nutrition is a vital component to their training regime and needs to be planned and practised accordingly. We have already discussed that the basics of an athlete’s diet will consist of a high amount of carbohydrates, moderate amount of protein, low amounts of fat, and loads of fluid. But how much of each food, and why?

Over the next few weeks we will have a dedicated page on each of the fuels required for sports people. If you are wanting more general advice rather than sporting advice, be sure to read the pages on Nutrition Food Values.

Fluid Intake for Sports

Nutrition for Sports people is not the only aspect an athlete needs to consider. Fluid intake is also extremely important all day every day, particularly when exercising in order to avoid dehydration.

When it is hot, athletes lose more fluid due to increased sweating. This fluid needs to be replenished so as the body can continue to perspire. If the body is unable to perspire, then the cooling mechanism of the body become affected and the athlete may overheat and suffer from heatstroke.

In general, women tend to sweat less than men when exercising at the same intensity, due to their lower body weight. However, thermoregulation (body temperature control) tends to be equivalent in both men and women.

It can be difficult to replace all fluid lost whilst exercising, due to the amount of sweat, and it can be hard to consume fluid during some sports. Athletes need to pre-plan their fluid intake before, during and after their sport.

An athlete can sweat between 600ml to 1 Litre per hour. However, during the heat this can increase the sweat rate up to 2 Litres per hour. The rate at which fluids and nutrients are absorbed and emptied by the stomach (gastric emptying) is approximately 1 to 1.2 Litres per hour.

Athletes need to try and consume 80% of their fluid loss during exercise, although most would only manage less than 50%. Regular fluid intake prior to the event is crucial.

Pre-Event Hydration

It is absolutely vital

that sports people are well hydrated before they exercise, especially endurance events. Increased fluid intake should precede an event by about 24 hours. To be sufficiently hydrated, urine should be clear. Although there is far less risk of dehydration for short events, adequate fluid intake is still important.

Sports people who have dehydrated to “make weight” are at higher risk of starting competition dehydrated. In order to achieve a good rate of gastric emptying during competition, then 5ml fluid per kg of body weight needs to be consumed just prior to competition.

The stomach needs to be continuously refilled with fluid at a recommeded rate of 150 to 250ml every 15 minutes. By having consistently large amounts of fluid in the stomach, gastric emptying is aided. However, exercise at high intensity can reduce the rate of gastric emptying.

Dehydration

Any level of dehydration will decrease sports performance – a 1% loss of body weight generally decreases sports performance by 5%. Sports people can not be trained to tolerate dehydration.

Thirst is NOT a good indicator of dehydration! If anyone is thirsty, they are already dehydrated. Regular fluid intake needs to become a habit for everybody. An athlete’s weight before and after training or competition indicates fluid loss. (1kg loss = 1 Litre fluid). Due to ongoing sweating and urination, athletes should replace 150% of their fluid loss.

Sports people involved in prolonged moderate to high intensity activities are most likely to suffer dehydration. Chronic dehydration can lead to fatigue. Plane travel or training in the heat is also very dehydrating.

Caffeine rich beverages (e.g. tea, coffee, cola, and alcohol) can increase dehydration. Tea and coffee should not exceed four drinks per day. Recommendations for alcohol intake are 1-2 standard drinks per day for women and 2-4 standard drinks per day for men, with 2 alcohol free days per week.

Effects of Dehydration

There are many adverse effects of dehydration including:

Body temperature and heart rate increases.
Perception of work/effort increases.
Aerobic capacity and muscular endurance are reduced.
Reduced concentration, skill learning ability and mental functioning.
Cramps, headaches and nausea.
Delayed gastric emptying, making it even harder to rehydrate (fluid intake when dehydrated can lead to stomach upsets).
Inability to urinate a few hours after an endurance event.

Sports Drinks

Sports drinks are thought to be very important component of nutrition for sports, and with good reasons! Carbohydrate and fluid ingestion have both been found to enhance sports performance, so together they have an even better effect. Sports drinks help to replace fluid, carbohydrate and small amounts of sodium simultaneously.

Typically, sports drinks are 6-8% carbohydrate; stronger concentrations can decrease the rate of gastric emptying. Lower concentrations mean less carbohydrates are consumed. They contain small amounts of sodium (10-25mmol/L). A level of 60-80mmol/L would enable rapid rehydration (i.e. assists fluid absorption from the intestine) but sports drinks manufacturers won’t add this amount of sodium due to taste. The sodium also replaces some of the sodium lost in sweat. Athletes just need to be cautious of the sugar and artificial sweetners found in most sports drinks.

Most people find sports drinks more appealing than water due to their taste and colour. They are consumed in greater quantities than soft drinks because they are not fizzy, and therefore less filling. If athletes plan on consuming sports drinks, they need to practice their fluid intake regime during training.

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