Veganism
From Healthywiki - a collaborative guide to alternative non-commercial Healthcare
Eating only vegan food is probably healthier.
Contents |
[edit] Health
The Physicians Committee for Responsible Medicine recommends what they call the "Four New Food Groups."[1] They suggest that vegans and vegetarians eat at least three servings of vegetables a day, including dark green, leafy vegetables such as broccoli, and dark yellow and orange such as carrots; five servings of whole grains (bread, rice, pasta); three of fruit; and two of legumes (beans, peas, lentils).[1]
[edit] Nutritional benefits
Scientists such as Roger Segelken and T. Colin Campbell believe that some diets (such as the standard American diet) are detrimental to health, and they believe that a vegan diet represents an improvement,[2][3] in part because vegan diets are often high enough in fruit and vegetables to meet or exceed the recommended fruit and vegetable intakes.
Benefits of vegetarian diets might be valid also for strict vegan dietsTemplate:Fact: according to the American Dietetic Association and Dietitians of Canada, diets that avoid meat tend to have lower levels of saturated fat, cholesterol, and animal protein, and higher levels of carbohydrates, fiber, magnesium, potassium, folate, and antioxidants, such as vitamins C and E, and phytochemicals.[4] People who avoid meat are reported to have lower body mass index than those following the average Canadian diet; from this follows lower death rates from ischemic heart disease; lower blood cholesterol levels; lower blood pressure; and lower rates of hypertension, type 2 diabetes, and prostate and colon cancer.[4]
A 1999 meta-study of five studies comparing vegetarian and non-vegetarian mortality rates in western countries found the mortality rate to be highest among vegans and those who eat meat regularly followed by vegetarians and those who eat meat infrequently. The lowest mortality rate was demonstrated by those who eat fish but no other meat. [5] A 2003 study of British vegetarians, including vegans, found similar mortality rates between vegetarians and other groups.[6]
A 2006 study found that in people with type 2 diabetes a low-fat vegan diet reduced weight, BMI, total cholesterol, and LDL cholesterol and did so to a greater extent than the diet prescribed by the American Diabetes Association.[7]
[edit] Nutritional concerns
[edit] Specific nutrients
The American Dietetic Association has said that "appropriately planned vegetarian diets are healthful, nutritionally adequate, and provide health benefits in the prevention and treatment of certain diseases."[4] However, poorly planned vegan diets can be deficient in nutrients such as [[Cobalamin|vitamin BTemplate:Ssub]],[8] vitamin D,[9] calcium,[10][9] iodine[11] and omega-3 fatty acids.[12] These deficiencies have potentially serious consequences, including anemia,[13] rickets[14] and cretinism[15] in children, and osteomalacia[14] and hypothyroidism[15] in adults.
[edit] Vitamin B12
Deficiencies in [[Vitamin B12|Vitamin BTemplate:Ssub]], a bacterial product that cannot be reliably found in plant foods,[16][17][13] can have serious health consequences, including anemia and neurodegenerative disease.[18] Although clinical BTemplate:Ssub deficiency is rare in vegans,[13] if a person has not eaten more than the daily needed amount of B12 over a long period before becoming a vegan then they may not have built up any significant store of the vitamin.[19] In a 2002 laboratory study, more of the strict vegan participants' BTemplate:Ssub and iron levels were compromised than those of lacto- or lacto-ovo-vegetarian participants.[20]
The Vegan Society and Vegan Outreach, and others, recommend that vegans either consistently eat foods fortified with BTemplate:Ssub or take a BTemplate:Ssub supplement.[21][22][23] Tempeh, seaweed, spirulina, organic produce, soil on unwashed vegetables, and intestinal bacteria have not been shown to be reliable sources of BTemplate:Ssub for the dietary needs of vegans.[24][25][13]
[edit] Calcium and vitamin D
It is recommended that vegans eat three servings per day of a high calcium food, such as fortified soy milk, and take a calcium supplement as necessary.[9][4] The EPIC-Oxford study showed that vegans have an increased risk of bone fractures over both meat eaters and vegetarians, likely due to lower dietary calcium intake, but that vegans consuming more than the UK's estimated average requirements for calcium of 525 mg/day had risk of bone fractures similar to other groups.[10][26]
The authors of The China Study argue that osteoporosis is linked to the consumption of animal protein because animal protein, unlike plant protein, increases the acidity of blood and tissues which is then neutralized by calcium pulled from the bones.[27] The authors add that "in our rural China Study, where the animal to plant ratio [for protein] was about 10%, the fracture rate is only one-fifth that of the U.S."[28]
For light-skinned people, adequate amounts of vitamin D may also be obtained by spending 15 to 30 minutes in the sunlight every few days. Dark-skinned people need significantly more sunlight to obtain the same amount of vitamin D, and sunlight exposure may be difficult for vegans in areas with low levels of sunlight during winter; in these cases supplementation is recommended.[14][29][16]
[edit] Iodine
Iodine supplementation may be necessary for vegans in countries where salt is not typically iodized, where it is iodized at low levels, or where, as in Britain or Ireland, animal products are used for iodine delivery.[21][11] Iodine can be obtained from most vegan multivitamins or from regular consumption of kelp.[21][11]
[edit] Pregnancies and children
According to the US National Institute of Health, "with appropriate food choices, vegan diets can be adequate for children at all ages."[30] The American Dietetic Association also considers well-planned vegan diets "appropriate for all stages of the life cycle, including pregnancy and lactation,"[4] but recommends that vegan mothers supplement for iron, vitamin D, and [[Cyanocobalamin|vitamin BTemplate:Ssub]].[31][32] Vitamin BTemplate:Ssub deficiency in lactating vegetarian mothers has been linked to deficiencies and neurological disorders in their children.[33][34] Some research suggests that the essential omega-3 fatty acid α-linolenic acid and its derivatives should also be supplemented in pregnant and lactating vegan mothers, since they are very low in most vegan diets, and the metabolically related docosahexaenoic acid (DHA) is essential to the developing visual system.[35] A maternal vegan diet has also been associated with low birth weight,[36] and a five times lower likelihood of having twins than those who eat animal products.[37]
Several cases of severe infant malnutrition and some fatalities have been associated with a poorly planned vegan diet,[38][39][40][41][42] and provoked criticism of vegan diets for children.[43][44] Parents involved in these cases were convicted on charges ranging from assault to felony murder. Addressing criticism of veganism, Dr. Amy Lanou, an expert witness for the prosecution in one of the cases, asserted that the child in that particular case "was not killed by a vegan diet" but that "the real problem was that he was not given enough food of any sort."[45]
[edit] Eating disorders
The American Dietetic Association indicates that vegetarian diets may be more common among adolescents with eating disorders but that the evidence suggests that the adoption of a vegetarian diet does not lead to eating disorders, rather that "vegetarian diets may be selected to camouflage an existing eating disorder."[4] Other studies and statements by dietitians and counselors support this conclusion.[46][47][48]
[edit] Vegan products
There are a vegan alternatives to normally non-vegan products:
