BMI = weight ÷ height²
Categories for BMI
Table 1
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1.2 Background Information
1.2.1 Who is a vegetarian? [5]
A vegetarian can be described as a person who refrains from or avoids eating meat including, chicken, fish, pork, beef or slaughter by-products. Some vegetarians may or may not choose to eat animal products such as eggs, milk, gelatin, or honey.
There are different types of vegetarians:
Some of the main types of vegetarian diets include:
1. Lacto vegetarian diet
2. Lacto-ovo vegetarian diet
3. Ovo vegetarian diet
Lacto vegetarian diet
This a vegetarian diet that avoids eating meat but does allow the consumption of diary products such as milk, butter, cheese, creame and yogurt etc. This diet does not however allow the consumption of eggs eventhough it is a diary product.
''Lacto'' is the Latin word for milk.
Lacto-ovo vegetarian diet
A lacto-ovo vegetarian diet is a diet that involves the consumption of eggs and diary products such as cheese, yogurt, and butter. It does not however allow the consumption of meat of any kind which includes pork, beef, chicken etc..
''Lacto'' means milk and '' ovo'' means egg.
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Ovo vegetarian diet
An ovo vegetarian can be described as a person who avoids eating all kinds of meat and
diary products but is allowed to consume eggs.
''Ovo'' means egg. Ovo vegetarians are sometimes nicknamed ''eggetarians''.
1.2.2 Who is a Vegan? [6]
A person who refrains from eating any animal product can be refered to as a Vegan. Vegans do not eat any animal products such as, milk, cheese, eggs, honey, gelatin etc..Many vegans choose not to wear clothes made from animal products, some examples of these products are wool, silk, and leather. Many of these vegans also choose not to wear makeup tested on animals.
1.2.3 Who is a Meat eater?
This is a person who eats meat and all animal products such as eggs, milk, cheese etc.. as a part of their diet.
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1.2.4 Why do people become vegetarians or vegans? [5]
People decide to become vegetarians or are raised as vegetarians for many different reasons. Some common motivators include;
a) Ethical Reasons: Some people are against the killing of animals. Many of these people believe that we should not use animals for food or produts from them such as their fur, or skin for leather, which require the killing of the animal, because they believe that animals are just as important in the world as people.
b) Environmental Reasons: Some people believe that we could feed many more people in the world by using the land we have to grow crops in order to feed people nutritious food, they also believe that it is a waste of resources to use land to grow grain or other crops that are fed to animals.
c) Health Reasons: Some people believe that a plant based or a vegetarian diet supplies them with a higher amount of carbohydrates, fruits and vegetables to help protect them against many diseases including cancers and heart disease.
Some people become vegetarians and vegans for religious reasons also. Many people become vegetarians and vegans for a combination of the reasons stated above.(5)
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1.2.5 What are the advantages of becoming a vegetarian or Vegan? [5]
There are a number of advantages to becoming or being a vegetarian or vegan.
- A Vegetarian and Vegan diet helps to increase heart health. This is because an average vegetarian consumes more nuts which often serve as a supplemental form of protein.Nuts contain ''good'' fats such as omega-3 and omega-6, this promotes good heart health by reducing ''bad'' cholestrol and unclogging arteries.Vegetarians also consume soy milk in addition to nuts which serves as a replacement to milk, it also helps to reduce ''bad'' cholestrol and has been linked to good heart health.
- Vegetarians and Vegans enjoy increased skin health. In addition to consuming larger quantities of nuts, which contain healthful oils, vegetarians and vegans tend to consume more fruits and vegetables, which are linked to good skin health because they are rich in essential vitamins. Some of these vitamins include vitamin A and vitamin E. These fruits and vegetables also contain high amounts of fiber which helps flush toxins out of the body, contributing to better skin health.
- Another advantage of becoming or being a vegetarian or vegan is that vegetarians and vegans have an increased natural consumption of antioxidants. Vitamin C and Vitamin E are two strong antioxidants which are commonly found in vegetarians meals. Antioxidants are foods that help prevent cancer by destroying free radicals. Foods containing vitamin C include: tomatoes, citrus fruits, peppers, kiwis etc.. vitamin E can be found in wheat germ, brown rice, walnuts, seed oils, a combination of these foods make up or is part of a well-balanced vegetarian or vegan diet.
Not only can a vegetarian and vegan diet be nutritional sufficient it can also help prevent cancer, help you have a better skin health and causes you to have a healthier heart.
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As there are advantages of becoming or being a vegan or vegetarian there are also disadvantages.
Other advantages of vegetarianism and veganism are;
- Increased energy.
- More food resources and food growing space.
- More humane treatment for animals.
- Improved quality of life because of lower incidence of some chronic diseases.
- Less expensive food sources.
- Lower death rates for some chronic diseases.
- Beneficial for overweight individuals.
- Beneficial for women with premensrual syndrome.
- Beneficial for individuals with diabetes, high blood pressure and cardiovascular diseases.
1.2.6 Are there any disadvantages of becoming or being a vegetarian or vegan? [6]
Some people think that the main risk is a lack of protein, but that is not the case at all because if a person eats a well balanced diet of vegetables, nuts, fruits, grains it makes up for the protein meat eaters get from consuming meat.
Vegans must pay attention to their intake of vitamin B12 since this vitamin is mostly found in animal products and a lack of this vitamin can cause a variety of irreversible neurological problems.
The most important health risks are related to a lack of certain vitamins and minerals especially vitamin B12. For this reason vegetarians and vegans must learn everything they can about a vegetarian and vegan diet in order to make it adequate.
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1.2.7 Advantages of a meat centered diet [7]
Meat is an excellent source of protein.
Protein is an essential nutrient which helps to build and repair body tissues such as muscles and organs, and is needed for growth and development of an individual. Most products produced by animals such as eggs, fish, meat, poultry contain high amounts of proteins, consuming these foods help supply the body with adequate and sufficient amounts of all the amino acids needed by the body.
A meat centered diet contains significant amounts of zinc which is important for a healthy immune system.
Meat contains more iron than most foods, and it is more easily used in the body than iron from other sources.The consumption of meat helps in the absorption of irons from foods like cereals and vegetables. Iron is also vital for making red blood cells. It also contains high amounts of niacin, vitamin B12, riboflavin, pyriodoxine and thiamin which are all sources of B-complex vitamins.
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1.2.8 Some health risks of eating a meat centered diet [7]
As there are advantages of eating meat, there are also disadvantages. Listed below are some health risks of eating meat.
- Eating a meat centered diet can cause an increased risk of bowel cancer, this was found for people who ate more than two servings of red meat per week.
- Excessive amounts of red meat can lead to a higher risk of osteoporosis (a disease in which bones become fragile and are more likely to break) due to an acid
byproduct from digesting very large amounts of proteins.
- Red meat is high in saturated fat and cholesterol which can lead to heart disease, cancer and other harmful diseases.
- Eating red meat every day can double the risks of Arthritis.
- The Mediterranean diet, which is low in red meat, has been shown to decrease the risk of Alzheimer's disease.
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2 .HYPOTHESIS:
A diet can be healthy whether it is a vegetarian diet, vegan diet or a meat centered diet. A balanced diet is a diet that contains all the appropriate nutrients in their right proportions. Examples of these nutrients include vitamins, proteins, carbohydrates, water, minerals and fats.
Eating excess or too little of some dietary components makes the diet unbalanced with might lead to malnutrition. A lack of a particular nutrient in the body can cause deficiency diseases, eventhough some disorders that are related to diets are due to excess eating. If the participants in this investigation all consumed a balanced diet then they would all be healthy especially in areas like having a normal body mass index. This is what I expect to show in the results of the investigation.
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3. Method
In order to carry out this investigation thirty participants were needed which included;
- 10 meat eaters
- 10 vegetarians
- 5 vegans
Participants had to be teenagers.
- the following information was needed from each participant;
- height
- weight
- blood pressure
- BMI
- how often they got a cold
The method used in this investigation was:
- First writing out a survey consisting of questions that would help in the investigation. The questions were meant to relate to the health of the individual and other basic information about the individual such as age, height etc. (see apendix)
- These surveys were handed out to individuals willing to participate in the investigation.
- The participants were asked to wait for about 10 to 20 mins so that the body would be at rest with a normal heart beat of 60-70 times per minute (see introduction) blood pressure was then taken by the school nurse.
- The information got from the survey was used in the investigation for conclusions to be drawn concerning the health of vegetarians, vegans and meat eaters so that conclusions would be drawn as to which diet was healthier.
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4.1 RESULTS
4.1.1 SURVEY RESULTS FOR VEGANS
Table 2
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4.1.2 SURVEY RESULTS FOR VEGETARIANS
Table 3
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4.1.2 SURVEY RESULTS FOR VEGETARIANS continued..
Table 4
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4.1.3 SURVEY FOR MEAT EATERS
Table 5
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4.1.3 SURVEY FOR MEAT EATERS continued..
Table 6
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5.1 DATA AND ANALYSIS
Mean Ages For Each Category Of Participants
Table 8
Mean Body Mass Index For Each Category Of Participants
Table 9
Standard Deviation Of BMI For Each Category Of Participants
Table 10
Analysis Using t-test [8]
From the sample result above, one can calculate for instance a 95% confidence level for each of the three population category assuming the populations are normally distributed.
- Vegetarian:
Mean for the body mass index is 21.13 with Standard Deviation 3.1825
Since we chose 95% Confidence level, then we have 5 degrees of freedom.
From the statistical table, the value of the 95% confidence level is 2.571
N= 10 (no of sample)
mean – 2.571 (standard deviation ÷ √N ) → for the lower value
mean + 2.571 (standard deviation ÷ √N ) → for the higher value
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21.13 – 2.571 σ/√N < µ < 21.13 + 2.571 σ/√N
21.13 – 2.571 (3.1825/√10) < µ < 21.13 + 2.571 (3.1825/√10)
18.677 < µ < 23.852
where µ represents the mean
I am 95% confident that the true BMI mean will fall between 18.677 and 23.852
If more interviews are made for the vegetarians, the interval would capture the true mean value of their Body Mass Index BMI in 95% of the time.
Vegans
Mean for the body mass index is 20.46 with Standard Deviation 1.8282
Since we chose 95% Confidence level then we have 5 degrees of freedom.
From the statistical table, the value of the 95% confidence level is 2.571
N = 5 (Number of samples)
20.46 – 2.571 σ/√N < µ < 20.46 + 2.571 σ/√N
20.46 – 2.571(1.8282/√5) < µ < 20.46 + 2.571 (1.8282/√5)
14.626 < µ < 18.830
The mean of BMI of vegans should fall between 14.626 and 18.830 but the calculated BMI is 20.46.
If more interviews are made for the vegans, the interval would capture the true mean value of their Body Mass Index BMI in 95% of the time.
Meat Eater
Mean for the body mass index is 20.39 with Standard Deviation 1.6634
Since we chose 95% Confidence level then we have 5 degrees of freedom.
From the statistical table, the value of the 95% confidence level is 2.571
N = 10 (Number of samples)
20.39 – 2.571 σ/√N < µ < 20.39 + 2.571 σ/√N
20.39 – 2.571(1.6634/√10) < µ < 20.39 + 2.571 (1.6634/√10)
9.373 < µ < 12.077
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The mean value calculated for meat eaters from the table shows that the meat eaters should have a mean value of 20.39 and a standard deviation of 1.6634. From the statistical test above it shows that
the mean value should fall between 9.373 and 12.077.
It can be seen that the t-test is not consistence with the results in table 3 for both the vegans and meat eaters
5.1.2 Futher Conclusions
The results from the survey showed that participants with abnormal weights( overweight and underweight ) ate an healthy and unbalanced diet. They either ate too much or too less of certain nutrients. Healthy participants that is participants with normal blood pressure, normal body mass index and those that exercised frequently all form the different categories of diets stated that they all ate balanced diets.
The participants that switched from one diet to the other stated that they either got sick more often or less often, this is because their body was begining to adapt to the new diet and some side effects may show this however depends from person to person.
To conclude, it can be seen that the hypothesis clearly supports the results because it did not matter what diet each participant was following what was taken into consideration was the amount of nutrients in the diet and how balanced the diet was. The participants for all the categories that were either underweight or overweight or got sick or had a cold often, this health failure is not particularly due to the type of diet they had but the manner in which they fed, they either ate too much of a particular nutrient or too less of it. If they had tried to balance their diet as some of the participants did then they might have had a normal body mass index and would not get sick so often.
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5.1.3 Limitations
Some limitations to this investigation was that there should have initially been ten vegetarians, ten vegans and ten meat eaters but I only came across five vegans who were willing to participate in the investigation, some of the vegans mentioned that they were not very commited to the diet and were taking gradual steps before they practising the diet completly. For this reason, the results and conclusions of this investigation might not be very reliable because the comparison was between ten vegetarians, five vegans and ten meat eaters. This also affected the t-test results.
Another limitation in this investigation is that the number of females compared to the number of males is uneven. For the vegetarians only females participated in the investigation, the vegans were represented by four females and one male, non vegetarians were represented by seven females and three males this again can have an effect on the investigation beacause the males participating in the investigation exercised more compared to the females therefore making them more physically fit and healthy.
5.1.4 Errors:There were no errors made in this investigation the data was read and analized correctly.
5.1.5 IMPROVEMENTS :
So what can we do to improve this investigation.This investigation would have improved if the participants that had switched from one diet to the other were asked to state their reasons for doing so and what diet they switched from. If they switched for health reasons then this information would have been helpful in determining whether their health have improved, stayed the same or had got worse.
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References And Biography
[1,5,6] – Available from:
Accessed: Sunday, 26 october 2008
[2] – Available from: URL:
Accessed: Sunday, 26 october 2008
[3] – Available from:
Accessed: Sunday, 26 october 2008
[4] -
Accessed: Sunday, 2 november 2008
[5] – Available from:
Accessed: Saturday, 11 october 2008
[6] – Available from:
Accessed: Saturday, 11 october 2008
[7] – Available from:
Accessed: Saturday,15 november 2008
[8] – Available from:
Accessed: Saturday, 15 nov 2008
the above mentioned website helped me understand statistics better
Books Used:
1.Becoming Vegan: the complete guide to adopting a healthy plant-based diet by Bruce Davis and Vesento Melina
2.A basic course in vegetarian & vegan nutrition by George L. Eisman
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7. APPENDIX
SURVEY FOR THE EXPERIMENT:
This is the survey I wrote in order for the investigation to be carried out.
1.How old are you?
2.What gender are you?
3.Are you a vegetarian, vegan or a meat eater?
If you are a vegetarian indicate if you eat eggs, fish, milk
4.How long have you had this diet?
5.How much do you weigh?
6.How tall are you?
7.Are you sick now?
8.When was the last time you had a cold?
9.How often do you have a cold?
10.How many days are you absent from school when you have a cold?
11.How often do you exercise? Once a week, twice, thrice, more or not at all
12.What is your blood pressure?
13.What is your body mass index (BMI) ?
14.State your regular diet for two days.
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