This is an assignment I wrote for my Yr 12 Nutrition class. It's based around the topic "Vegetarianism and Reducing your Carbon Footprint". I hope you enjoy reading it.
Introduction
Today we often hear about �global warming� and �carbon footprints� and ways we can reduce these. One way is to change from an omnivorous diet to a vegetarian, or vegan diet, which consists of no meat or no animal products. But is a vegetarian diet safe? Can a person get all the necessary nutrients without consuming meat?
Scope of the Study
The aim of this investigation is to determine whether a vegetarian diet is helpful in reducing an individual�s carbon footprint. It will also be used to determine whether a vegetarian diet is safe.
The focus questions chosen to guide this study are:
1. Compare nutrition value of a vegetarian teenager�s diet to that of an omnivorous teenager�s diet.
2. What are the benefits of a vegetarian diet in relation to nutrition and carbon footprint?
3. What are the risks/disadvantages of a vegetarian diet in relation to nutrition and carbon footprint?
Methodology
A range of primary and secondary resources will be used to investigate the topic.
Primary:
~~A food diary to compare the diets of a vegetarian and an omnivorous teenager.
Secondary:
~~Magazine articles from reputable medical magazines.
~~The internet
~~Nutrition books for other vegetarian and nutrition related information.
I acknowledge that some of these sources will contain a certain amount of bias. Vegetarian opinion may be pro-vegetarianism. People that don�t believe that global warming is an issue, or don�t believe that people are its cause, may not be pro-vegetarianism. I will endeavour to pick credible resources and recognise that some bias may be evident.
Discussion of Findings
Compare nutrition value of a vegetarian teenager�s diet to that of an omnivorous teenager�s diet.
Approximately 2% of teenagers are vegetarian. But is it really the healthier option? The general public and some health professionals claim that vegetarians are deficient in iron, vitamin B12 and zinc. But this is not entirely true.
Teenage girls can be at risk of developing anaemia, but only if they have a low iron intake. Eating things like eggs, tofu, nuts, legumes and dairy products regularly will stop any problems. Vitamin C in the diet will also help with the absorption of iron.
Vitamin B12 is found in animal products such as eggs and dairy products. Zinc is found in whole grains, breads and most cereals (which are regularly fortified) eggs and milk. Neither of these nutrients will be deficient in a balanced vegetarian diet.
Vegan diets are likely to have deficiencies in vitamin B12, but in Australia there are B12 fortified soy milks, textured vegetable protein and yeast extracts to counter this.
Any well balanced, planned vegetarian diet is a healthy alternative to an omnivorous diet. Unfortunately many teenagers (especially girls) become vegetarian for fast weight loss, or to hide an eating disorder . These diets are often extremely unhealthy and are not an alternative to an omnivorous diet.
According to a food diary completed by a vegetarian teenager and an omnivorous teenager (17 year olds, average foods over a 7 day period) , both diets were compliant with Nutrition Australia�s Healthy Eating Pyramid . The vegetarian diet was also compliant with Nutrition Australia�s Healthy Eating Pyramid for Lacto-ovo Vegetarians.
Vegetarians, following a healthy diet, are likely to have these benefits:
~~Lower blood pressure
~~Lower cholesterol levels and less heart disease
~~Less chance of colon, breast, ovarian and prostate cancers
~~Lower BMI and less likely to be over weight
~~Less likely to develop diabetes
~~Less likely to develop gall stones.
From this information, we can see that a vegetarian diet is a healthy alternative, and, in some ways, a better alternative, to an omnivorous diet. They tend to eat a lot of fruit, vegetables and grains, which should make up the bulk of any diet, vegetarian or not. With a well balanced diet there is no risk of deficiency of any nutrients.
What are the benefits of a vegetarian diet in relation to nutrition and carbon footprint?
A vegetarian diet is often praised for having greater nutritional value than an omnivorous one. But this is not always so. It has been proven that a vegetarian diet can help prevent many diseases like obesity, coronary heart disease, hypertension and diet related cancers. But this is only if the diet is healthy.
A healthy vegetarian diet follows these guidelines:
~~Contain mostly fruit, vegetable and grains
~~Contain a moderate amount of dairy and eggs, as well as other protein rich foods, such as tofu and other soy products
~~Contain small amounts of oil fat and sugar
~~The recommended ratio of cereals to legumes, which is 70:30
The Healthy Eating Pyramid for Lacto-ovo Vegetarians is essentially the same as any other food pyramid, but it has a larger space for �Eat Most�, there is no meat and special foods like tofu are added.
In any healthy vegetarian diet, all nutrients are catered for, but nutrients that people often worry about are protein, iron, calcium and vitamin B12.
Protein, calcium and vitamin B12 can be easily found in eggs and dairy products. Iron can be a problem in high iron requiring individuals, such as teenage girls or pregnant women, but as discussed on page 3 can be adequate, though iron supplements may need to be taken.
Vegans have slightly different issues. Meat is the only provider of all the essential proteins, but by mixing different foods containing different proteins, they can all be accessed. Foods of plant origin do not contain vitamin B12, so vegans will need to eat foods that have been fortified with this vitamin. As reserves of vitamin B12 are large in relation to the small daily requirement, deficiencies take many years to appear.
But what about the carbon footprint of a vegetarian diet? In relation to how the food is produced, vegetarian diets are overall better.
The grain wasted for livestock feed is enormous. The percentage of US grain feed to livestock has risen from 10% in 1900, to over 60% today. This use of more than one third of the world�s grain is particularly wasteful. This is a huge amount of food that could have been better used by being consumed by humans. Raising beef cattle requires the most land per kilogram of food, at 20.9m2 compared to vegetables at between 0.2m2 (potatoes) to 0.3m2 (other vegetables) and fruit at 0.5m2. Therefore a typical European omnivorous diet would require five times more land than that required for a varied vegan diet. We simply don�t have enough land to feed everyone on an animal based diet. 840 million people don�t have enough food and the rest of us continue to waste two thirds of agricultural land on beef, when we could be doing the earth a greater service by becoming vegetarian or by just eating less meat. Not to mention the water used in beef production. It has been calculated that a huge 100,000 litres of water is used to produce 1kilogram of beef, compared to 500 litres per kilogram of potatoes and 900 litres for a kilogram of wheat.
Another major problem is the amount of methane produced from beef production. Today�s society places so much emphasis on carbon dioxide emissions when methane is a more potent global warmer than CO2. It is true that humans produce more CO2 than any other greenhouse gas, but this is combated by the fact that the largest CO2 producers, cars and power plants, also produce aerosols, which have a cooling effect on global temperatures, so there is roughly a zero effect on global temperatures overall. Methane is 21 times more powerful than CO2 as a greenhouse gas. CO2 concentrations have risen approximately 31% since pre-industrial times but methane concentrations have more than doubled. The main source of methane worldwide is animal agriculture.
Animal agriculture creates more than one hundred million tons of methane each year, as well as 18% of carbon emissions. 85% of this methane is produced in the digestive processes of livestock, and 15% from untreated farm waste, which is also the main source of water pollution in the US. The global demand for meat is on the rise. Consumption of meat has increased five times in the past fifty years with the world�s population expected to increase from six billion today, to nine billion by 2050.
Benefits to the environment from less meat consumption include less tropospheric ozone, which is caused by methane and results in problems in human health and agriculture, less water used by growing livestock, as well as less deforestation and desertification caused by land clearing for livestock use. There will be less ecological stress because plant based foods require less water and deliver greater yields per hectare.
A vegetarian diet can be extremely beneficial to your health, and the environment. Animals are saved, which is one of the main reasons people become vegetarian and the environment also benefits.
What are the risks/disadvantages of a vegetarian diet in relation to nutrition and carbon footprint?
There are many ways in which a vegetarian diet can be unhealthy. A vegetarian diet is not simply cutting all meat, poultry and fish from your diet, and supplementing this with junk food. Hot chips and chocolate, while being vegetables and dairy, are NOT �vegetarian� food. Meat needs to be supplemented by meat alternatives, like soybean products and lentils.
Unfortunately some people, notably teenage girls, become a vegetarian/vegan for fast weight loss or to hide an eating disorder. These diets are often not researched, which is essential when becoming vegetarian. According to a study, although meatless teens ate more fruit and vegetables than their meat-eating peers, they were twice as likely to diet frequently, four times as likely to diet more intensively and eight times as likely to abuse laxatives.
One of the main problems is the possible lack of vitamins and other nutrients received. Most people are worried that there is not enough protein, iron, zinc and vitamin B12 available in the diet. This is not true, if a diet is carefully planned.
~~A lack of protein can cause hair loss. Hair is protein and when someone develops protein malnutrition, the body will put hair into the �resting phase�. Hair loss may be experienced a few months later.
~~Another problem may be in skin. Protein is used to repair dead skin cells, and a lack of it can cause problems in the health of your skin. The most worrying issue with a lack of protein is muscle breakdown. When the body doesn�t get enough protein, it takes protein from your muscles, resulting in your body becoming weak and your muscles breaking down.
~~Not getting enough iron in your body causes anaemia. Anaemia causes a loss of red blood cells in the body, resulting in extreme tiredness, fainting and headaches.
~~A lack of zinc can cause dwarfism, problems with male and female reproduction, brain disorders and nail, skin and hair conditions.
~~Vitamin B12 deficiency causes tiredness, anaemia, decreased concentration and memory. These are early symptoms and if not treated it can develop into nerve damage, mania and psychosis.
In relation to the carbon footprint, a vegetarian diet is apparently very good. Plants recycle carbon dioxide during photosynthesis. But how far do the vegetables and tofu have to travel to get to where the vegetarians are?
Vegetables that are locally grown and in season are the best choice, but this is not the most common trend. Many people believe that just eating the vegetables cuts carbon emissions, but veggies that travel a long way can�t be the best choice.
Soybean is also relatively bad for the environment. Even though it�s a great vegetarian food, many hectares of land are cleared for soybean production. The Amazon rainforest is currently experiencing mass deforestation due to worldwide demand for soybean. There was a 40 percent jump in deforestation in the Amazon in 2002 and even the cattle herds have been pushed away just for soybean production.
Most soybeans are genetically modified and all soybeans contain high levels of pesticide contamination. They are also high in phytates, which prevent the absorption of minerals like calcium, magnesium, iron and zinc, which are important in a vegetarian diet.
A vegetarian diet can be a very healthy way of eating, but like any diet, there are downsides and possible risks that need to be addresses. Young children and teenagers need to be monitored to ensure they are getting all their nutrients.
Conclusion
From this information we can see that a vegetarian diet is indeed a healthy option and can be safe. Although there are risks, in carefully planned vegetarian diet in which a variety of foods are eaten, will not cause health problems. A vegetarian diet can also be beneficial in helping to reduce an individual�s carbon footprint. Less land is degraded, and there are less methane emissions from animal agriculture.
