Saturday, May 21, 2011

THE PROS AND CONS OF A MEAT-FREE DIET



The general consensus is often that a vegetarian diet provides important health benefits, and on average vegetarians have better health than the general public. A vegetarian diet is broadly defined as a diet excluding animal products such a meat, fish and poultry. However, there is no single vegetarian eating pattern as vegetarian diets vary depending on the extent to which animal products are excluded. There are various reasons that people choose to adopt vegetarian diets including health reason, religion/culture, ethical/moral reasons and animal welfare, and economic, ecological and environmental reasons. Below are the various vegetarian diets followed:

DEMI-VEGETARIAN: Exclude red meat but eat fish and poultry
PESCATARIAN: Eat fish, no red meat, no poultry
LACTO-OVO: Exclude meat, fish, poultry and ingredients derived from them – eat milk and eggs
VEGAN: Exclude all animal flesh and products
FRUITARIAN: Eat raw fruit, nuts, seeds, sprouted pulses
MACROBIOTIC: Based on Yin and Yang – 7 levels that become more restrictive, vegan diet and occasional fish

HEALTH IMPLICATIONS OF VEGETARIAN DIET
·         Vegetarians appear to have lower morbidity, mortality from chronic diseases and lower incidence of risk factors
 BENEFITS OF VEGETARIAN DIET
·         Approach UK recommendations more closely than general population
·         Tend to be lower in saturated fat, higher in starchy food, fibre and fruit and vegetables
·         Greater intake of fibre leads to greater satiation
·         Lower weight and BMI than omnivores, vegans weigh the least due to decreased calories
·         Low blood lipids levels, lower rates of hypertension and lower rates of heart disease
·         Higher levels of plasma total antioxidants
·         Data from 5 prospective studies (1999) compared death rates from common diseases in vegetarians and non-vegetarians with similar lifestyles. The studies found a 24% reduction in mortality from ischaemic heart disease, however, no difference in mortality from cerebrovascular disease, stomach, lung, colorectal, breast, prostate cancer and no difference in mortality for all other causes combined

RISKS OF VEGETARIAN DIET
·         Some individuals adopt a vegetarian diet to mask their dietary behaviour from others – eg. anorexia nervosa
·         People may be uneducated when adopting a vegetarian diet which can result in increased consumption of high fat foods (cheese, eggs, ready meals) in groups unfamiliar with cooking beans/pulses
·         Exclusion of meat can lead to higher intake of eggs and dairy products, both of which are high in calories and fat and contain cholesterol and saturated fat.
·         Some evidence suggests that consuming high amounts of protein from milk and eggs can lead to some cancers including prostate and ovarian cancer and also autoimmune diseases.
·         Despite it being considered that vegetarian diets do not provide all the necessary vitamins and minerals due to the exclusion of all/certain animal products this is not true. While meat diets have easier access to all nutrients, vegetarian diets can provide the exact match as a result of the fortification of some food products.
·         B12 comes solely from animal products so can cause deficiency in some vegetarians depending on which diet is followed, however some soy products and breakfast cereals are fortified with B12 providing alternative sources. A B12 supplement can also be taken if fortified products are not available or not appropriate.
·         Vegetarians smoke less and are more active so other factors than just not eating meat contribute to health benefits
NUTRITIONAL CONSIDERATION FOR VEGETARIANS: ENERGY
·         Important to provide sufficient energy for growth
·         Prevent catabolism of protein
·         Vegetarians tend to have similar energy intake to non-vegetarians
·         Lacto-ovo children tend to have similar energy intake and growth patterns to omnivores
·         Diet can be bulky (non-digestive fibre)
o   Potential probably for infants, children and people with poor appetite
NUTRITIONAL CONSIDERATION FOR VEGANS: ENERGY
·         Energy intake can be decreased, especially men
·         Protein energy malnutrition, growth retardation and delayed psychomotor development have been reported in infants and children fed:
o   Macrobiotic diet
o   Rastafarian diet
o   Vegan diet
Energy intake for Vegans can be increased by increasing:

PROTEIN
Concern expressed that vegan might have inadequate protein intake due to:
·         Decreased protein content of plant foods
·         Fact that plant foods don’t contain all of the essential amino acids
o   Lacto-ovo receive all essential amino acids from milk/eggs
o   Combination of pulses (including peanuts), whole grains or pulses with nuts and seeds
o   Protein does not need to be combined at each meal, a varied intake is ideal
FAT
·         Vegetarians tend to have a decreased intake of saturated fat but total fat similar to non-vegetarians
·         Eg. cheese, nuts, vegetable fats, cakes, chocolate, processed foods
 CARBOHYDRATES
·         Increased intake in vegetarians
·         Vegans have highest intake of all diets
·         Sugar intake is similar, however it have been found that 15% of energy consumed by vegan children is in the form of sugar, mostly from fruit juice.
DIETARY FIBRE
·         Increased fibre intake in vegetarians due to high consumption of whole grains
NB. Excessive intake is not advised for infants, young children, elderly, people with poor appetite due to bulky nature

·         No evidence of compromised mineral status in groups that have high fibre diet
VITAMINS
·         Generally adequate intake in vegetarians
·         Risk of B12 deficiency – mostly vegans where no animals products are consumed
o   B12 deficiency can cause anaemia
§  B12 deficiency can be masked by high folate intake and riboflavin and vit D
IRON
·         No evidence of high prevalence of anaemia
·         Adult pre-menopausal women tend to have lower ferritin levels
·         Greater risk of anaemia in high risk groups – infancy, pregnancy, blood loss
CALCIUM
·         Similar intake to omnivores
·         Vegans have decreased intake, adults tend to consume less than RNI
Overall, a vegetarian diet has many benefits, however, to be a good vegetarian one must also understand the risks such a diet carries in order to a adopt a style of eating that promotes good health. While red meat may be high in saturated fat, so is cheese, so high consumption of meals such as jacket potatoes with cheese, cheesy pasta and cheese toasties are not a good alternative.

If you are unsure of how to cook beans and pulses/legumes try the following links which provide useful tips and recipes:




Consuming a vegetarian diet that is high in starchy carbohydrates such as bread, potato and pasta is not ideal, especially if white products. Unless you are physically active, these simple carbohydrates will break down and be stored as fat which could potentially mean undesired weight gain. Opt for grains such as quinoa, wild rice and sprouting buckwheat and avoid consuming high quantities of couscous – it is just tiny Moroccan pasta!

Ok, well that’s pretty much it so I hope you have found some useful information in the post.

Until next time,

N xx

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