'The United States Department of Agriculture is in the business of protecting and promoting agriculture in our country. In large part, that means advocating for the meat and dairy industries. However, the Department is also charged with issuing dieatary recommendations for the American public. A conflict of interest? You bet' (Havala, p.45)
(Note: More or less the same situation exists here in Australia. I know the nutritional pamphlets they showed us at school heavily emphasised the 'importance' of animal products to a 'normal' diet. However, the best book I found was an American one, so most of the information pertains to the U.S, except the parts that are universal).
Many people assume that vegetarians must be missing out on something important in the way of nutrition. Fortunately for me, they are wrong about this.
One of the major things people often think a vegetarian diet is missing is protein. If asked to list foods high in protein, most people would list types of meat. However, meat is not the only source of protein. Protein is found in ALL living things, animal, plant or fungus. It makes up the basic structure of all living cells. You can easily get enough protein from eating only plant foods. "In fact, as long as you get enough calories to meet your energy needs, it's nearly impossible to be deficient in protein' (Haval, p.36). Some protein rich foods include peanut butter and pasta. Diets which contain a lot of animal products can be too high in protein. This has an effect on the kidneys, causing more calcium to pass into the urine. 'That's part of the reason that standard recommendations for calcium intake for Americans are so high. The recommendations are jacked up to compensate for calcium losses that are caused by Flintstones-sized standing rib roasts and 16-ounce steaks that cover the plate. Americans love meat, and they pay for it with calcium loss.' (Havala p.17)
Another thing people often don't think vegetarians get enough of is iron. 'Iron is a mineral that forms part of the haemoglobin of red blood cells and helps carry oxygen to the body's cells' (Havala p.56). Too little iron, or iron deficiency can make you feel tired and lethargic all the time. Iron deficiency is no more common among vegetarians than non vegetarians. Many plant foods are very rich in iron. The iron found in plant foods is called Nonheme iron. It is not absorbed by the body as readily as the Heme iron found in animal products. However, other substances found in these plant foods help the body absorb the iron more readily. The most potent of these enhancers is vitamin C. 'When vegetarians eat a rich food source of vitamin C with a meal, they can enhance the absorption of the iron present in the meal by as much as 20 times' (Havala p57). There are also substances which inhibit the absorption of iron, such as caffeine and the tannins in tea, but as long as you eat a reasonable variety of different foods it all balances out. Vegetarians need more iron in their diets than nonvegetarians because the iron in plant foods is not as readily absorbed by the body. However, on average, vegetarians get more iron in their diets than nonvegetarians since they tend to eat a much larger variety of vegetables.
It is possible to consume too much iron, and this can be hazardous to human health. It can lead to a disease called 'haemachromatosis', a condition where the body stores too much iron. This can be exacerbated by a carnivorous diet.
'Scientists believe that when sufficient quantities of heme iron are present, such as in diets that centre on meat, cholesterol is oxidized into a form that is more readily absorbed by the arteries. This leads to increased rates of coronary artery the case of nonheme iron, the body absorbs only what it needs' (Havala p.61).
It may therefore, be healthier to get iron from plant sources rather than animal ones. Another way to prevent ill health caused by excess iron in the body, and help other people in the process, is to give blood regularly. This is mainly beneficial to men, as young women lose iron through menstruation.
I am not a vegan, but I was also interested to read some of the facts about eating a vegan diet, in particular the effects of not consuming dairy products on a person's calcium intake.
When you think about it, drinking cow's milk is a very strange thing to do. All mammals produce milk to feed their offspring, but you don't see pigs drinking goat's milk, or platypuses (platypi?) drinking echidna's milk. Milk is specific. It's designed to contain what's needed to nourish one specific kind of baby animal. Human mothers produce their own breast milk to feed their offspring, which is specifically tailored to nourish a human baby.
'During infancy, your body produces an enyzyme called lactase. Lactase helps the body digest lactose, the form of sugar found in milk. As a baby becomes a toddler, she needs less of her mother's mild, so the body's production of lactase also begins to decline. By the time a human child is three to five years of age, she has stopped breast-feeding and doesn't naturally need milk in her diet anymore. At that time, the body has stopped or nearly stopped producing lactase. That's natural too' (Havala p.44)
Contrary to what those of us in Western countries are told in school, adult humans do not need milk. Most adult humans cannot digest it because when their bodies stopped producing lactase they became lactose intolerant. This condition is caused by the sugars in milk moving into the intestines without having been completely digested. Symptoms include gas, bloating, abdominal cramps, and diarrhea. Most people of Asian, African, Mediterranean, Native American or South American descent are lactose intolerant. People of Northern European descent are not. 'That's thought to be due to a genetic mutation that occurred some time in generations past that allowed those people to continue to produce lactase into adulthood'(Havala p.44). This allowed people in Northern Europe to develop a taste for dairy products. When they colonised North America and Australia they brought with them traditions of making and eating cheese and other dairy foods. Whatever you think about the ethics of consuming dairy products, we ought to at least be honest about our reasons for it. We are told by the dairy industry that milk is an essential part of a balanced diet, which is untrue. They ought to admit to the public that the best reason for consuming dairy foods is simply because you like them.
For people who choose not to eat dairy foods, an adequate source of calcium can be found in broccoli, Chinese cabbage, dark green leafy vegetables, legumes (beans), tofu processed with calcium, almonds, sesame seeds, dried figs and calcium fortified orange juice.
As long as you're sensible about it and eat reasonable variety of foods, a vegetarian diet will not lack for vitamins or any other important nutrients. The choice is open to anyone who wants to give it a try.
Sources and suggested reading:
Havala, Suzanne,'The complete Idiot's guide to being Vegetarian', Macmillan Publishing, 1999