A philosophy of eating, like vegetarianism, has to be understood in the context of the motivation for doing it. The reason for adopting a vegetarian or vegan way of life may be: ethical, animal welfare, environmental, health, economic, world hunger issues or religious beliefs.
In the broadest sense, a vegetarian is a person who does not eat meat, fowl or fish or products containing these foods. However within this broad term, there are a number of sub-groups of vegetarianism. Some of these include:
Demi-vegetarian – the only restriction is red meat
Partial vegetarian – eat fish and poultry
Ovo-lacto-vegetarian – eat animal products such as egg and dairy
Lacto-vegetarian – only dairy products are eaten
Vegans – eat no animal products at all. These are the most dedicated vegetarians.
Vegans eat no animal meat or by products of animals, and avoid making use of animal derivatives (like leather shoes) and animal tested products (like cosmetics) in their lifestyle. Many people who have chosen a vegan lifestyle have done so for ethical reasons, especially the cruelty and exploitation involved in the making of animal products.
Vegetarianism -The health benefits of a plant-based diet
There is little disputing that an appropriately planned vegetarian diet has a wide range of health benefits. Vegetarians are reported to have a lower body mass index than non-vegetarians. They experience lower rates of death from ischaemic heart disease, show lower blood cholesterol, lower blood pressure, and lower rates of hypertension, type II diabetes and prostate and colon cancer. These are some of the adverse effects of animal products eaten in excess over a lifetime.
A vegetarian diet offers a variety of nutritional benefits. It is a diet low in saturated fat, cholesterol, and animal protein, whilst being higher in carbohydrates, fiber, magnesium, potassium, folate, boron and the antioxidants vitamins C and E, and cancer-preventing phytochemicals, or plant chemicals. Due to the emphasis on fresh fruits and vegetables, this diet tends to be more alkaline unlike the acidity produced by eating animal proteins. Acidity in the body causes calcium to leach from the bones to act as a buffer, thereby contributing to bone demineralisation. Poor quality animal proteins can contain hormones and antibiotics, adversely affecting our health.
Vegetarianism -Nutrient deficiencies to watch out for in a vegan / vegetarian diet
Whilst a vegetarian based diet has many advantages, it can also contain low amounts of certain essential nutrients, if it is not sufficiently balanced:
It has been argued that vegans are no more vulnerable to vitamin B12 deficiency than meat eaters. This is because vegans have a more favorable balance of gut flora that produces sufficient B12.
Sources – Occurs naturally only in animal products. Can obtain it from dairy foods and eggs. Soil is a rich source of vitamin B12, and it is thought that lightly washed, freshly harvested vegetables were a viable source. However modern food practices and the sterile nature of food and the environment do not make this a viable source.
Required for -DNA synthesis, red blood cell production, energy production, insulation of nerve cells, homocysteine metabolism, fat burning, bone building, neurotransmitter and hormone production
Deficiencies – pernicious anaemia, can raise homocysteine levels, increasing the risk of heart disease
Vegetarian sources – fortified foods, yeast extract, fortified soya milk. Micro-algae (spirulina, chlorella and blue-green algae) is thought to be an excellent source of B12 although there is debate as to whether it is in a bio-available form to the body.
Infants, children and older adults synthesize vitamin D less efficiently
Sources – primarily comes from the action of sunlight on the skin. Normally present in animal sources – butter, eggs, oily fish, milk, liver. Also present in some fortified margarine.
Required for – bone formation – maintenance of plasma calcium levels. It is important in the prevention of osteoporosis.
Deficiencies – rickets (in children), osteoporosis, diarrhoea, insomnia, nervousness and muscle twitches
Vegetarian sources – sunshine, supplement with a daily multivitamin
Preformed vitamin A is only found in animal foods. Vegetarians rely on vitamin A from consumption and conversion of dietary beta carotene. The inclusion of 3 servings per day of yellow / orange fruit and vegetables or dark green leafy vegetables is thought to be sufficient to meet Vitamin A requirements.
Animal meat is a good source of vitamin B2 and non-meat eaters might have a deficiency of this vitamin. Non meat sources of vitamin B2 include: almonds, mushrooms, asparagus, bananas, beans, broccoli, figs, kale, lentils, peas, sesame seeds, sweet potatoes, tofu, tempeh and wheat germ.
Calcium is a mineral vital for nerve transmission and muscular contraction and healthy teeth and bones. A strict vegan diet can be deficient in this mineral, if a wide-enough range of calcium-rich greens, vegetables, nuts and beans are not consumed. Boron, a mineral which is effective in reducing calcium loss, is found mainly in fruits, vegetables and nuts. Higher intake of potassium and vitamin K amongst vegetarians is a benefit in safeguarding against bone loss.
Vegetarian sources of calcium- broccoli, collards, kale, bok choy, turnip greens, okra, nuts, seeds, pulses, fortified soya products, tofu, figs, blackstrap molasses. A number of these foods are also excellent sources of magnesium which is needed for calcium absorption.
Haem-iron found in animal blood, especially red meat, is absorbed five times more efficiently than plant sources which contain only non-haeme iron. However, excess haem iron can act as a pro-oxidant. This possibly explains the link between arterial damage and colorectal cancer seen in meat eaters.
The main inhibitor of iron absorption in a vegetarian diet, is phytates found in wheat. However, vitamin C which is typically higher in a plant based diet, consumed at the same time as iron, can help to improve absorption.
Vegetarian sources – tofu, kidney beans, lentils, pumpkin seeds, quinoa, watercress, parsley, mushrooms, dried fruits, potato skin, asparagus, beetroots, oatmeal, blackstrap molasses
Animal protein is believed to enhance the absorption of zinc, whereas phytates (in wheat products) bind to and excretes zinc. It is thought that zinc is likely to be lower in a vegetarian diet.
Vegetarian sources – aduki beans, navy beans, cashew nuts, pumpkin seeds, sunflower seeds, ginger root, Brazil nuts
Studies suggest that vegans who do not consume iodise salt or sea vegetables are at risk of iodine deficiency. The fact that vegan diets are also often high in goitrogens (foods which inhibit thyroid function), such as soya products and cruciferous vegetables, suggests a possible issue in relation to thyroid insufficiency.
Vegetarian sources – kelp, sea vegetables and iodised salt
Omega 3 EFA's
Vegetarian diets can be low in Omega 3 fatty acids and their derivative EPA and DHA, sourced directly from fish oils. It is therefore recommended that vegetarians include good sources of Omega 3 sources such as flaxseed, pumpkin and walnut in their diets. Zinc is one of the co-factors required for the conversion of omega 3 fatty acids to DHA and EPA. If there is a deficiency of zinc in the body, it is now possible to obtain vegan sources of DHA, derived from micro-algae.
There is absolutely no reason why a vegan diet cannot satisfy the protein needs of the body. Vegan sources of protein include beans and pulses, soya based products, nuts and seeds and grains. Some vegan foods such as quinoa are a good source of all eight essential amino acids. A combination of a complex carbohydrate and a plant protein (ie brown rice and beans) at the same meal, or eaten over the course of the day, will create a complete protein.
A well-planned vegan or vegetarian lifestyle has many benefits and can be suitable for all stages of life. However, it is important to ensure a balanced diet that supplies all the nutrients needed to stay healthy. Blood tests can be done to assess mineral levels if deficiencies are suspected. Good quality, suitable supplements can be taken to address any nutrients that may be lacking.
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