Popular Dietary Models - Vegetarian and Vegan Diet

Question 1

Vegetarian and Vegan Diet

Answer 1

Greek philosopher, Pythagoras stressed the importance of a vegetarian diet for maintaining physical and mental health as early as the 6th century B.C.!

• Vegetarian diet: Plant based but includes small amounts of eggs and dairy products while excluding meat, fish and poultry.
• Vegan diet: Vegetarian diet that excludes all animal-derived ingredients including eggs, dairy products and honey / bee products.
• This may extend to non-dietary aspects as well including avoidance of leather, fur, silk, wool and cosmetics derived from or tested on animals.

Question 2

Vegetarian diet:

Answer 2

• Vegetarian diet: Plant based but includes small amounts of eggs and dairy products while excluding meat, fish and poultry.

Question 3

Vegan diet:

Answer 3

• Vegan diet: Vegetarian diet that excludes all animal-derived ingredients including eggs, dairy products and honey / bee products.

Question 4

Well-formulated vegetarian / vegan diets

Answer 4

Well-formulated vegetarian / vegan diets are associated with numerous health benefits.
* Well-formulated vegetarian / vegan diets are based on fresh fruit and vegetables, nuts, seeds, legumes and grains.
* Foods are whole, organic, seasonal and locally sourced.
* Vegetarian / vegan diets that are based around pre-packed, refined foods that are high in sugars and highly-processed oils are no more healthy than their meat-eating equivalents.
* The quality of the food must always be considered.
* Healthy vegetarian / vegan diets are free of processed, refined foods.

Question 5

Benefits:

Answer 5

• Less obesity: Translates into better metabolic health. Obesity is linked with an increased risk of heart disease, hypertension, diabetes, musculoskeletal disorders and cancers.
• Improves glycaemic control:
  o Plant foods are high in fibre, which slows glucose absorption.
  o Linked to increased insulin sensitivity —an effect attributed, at least in part, to increased production of SCFAs that interact with tissue receptors to reduce inflammation that causes insulin resistance and encourages production of GLP-1. (GLP-1 = Glucagon-like peptide 1. Stimulates pancreatic insulin production and release)
• Lower intake of environmental contaminants: Exposure to heavy metals, DDT, PCBs, etc., is reduced, as these substances accumulate as we move up the food chain (more in animal products).
• Reduced risk of foodborne diseases: The risk of contracting E. coli, salmonella, listeria, campylobacter and other food-borne pathogens is significantly lower.
• Improved longevity: Well-formulated plant-based diets are associated with increased longevity.
• Reduced risk of heart diseases:
  o Total cholesterol levels are up to 14% lower in vegetarians and 35% lower in vegans.
  o Vegetarians have lower blood pressure (5‒10 mm Hg less) than non-vegetarians.
  o Hypertension rates in vegetarians are one-third to one-half that of non-vegetarians.
  o Healthy vegetarians have higher levels of antioxidants and lower levels of oxidised LDL cholesterol than non-vegetarians.
• Reduced risk of cancer: Healthy vegan and vegetarian diets are associated with decreased risk of many types of cancer.
  o Based on higher consumption of plant foods that are rich in immune-enhancing and antioxidant vitamins, minerals and phytonutrients e.g. vitamins C and E, carotenoids, flavonoids including anthocyanins and quercetin.
  o Reduced incidence of other risk factors for cancer such as overweight / obesity and less exposure to carcinogens that are in cooked meats such as heterocyclic amines.

Question 6

Ensuring a balanced diet:

Answer 6

• A varied vegetarian and vegan diet provides an abundance of nutrients.
• There are key nutrients that are less abundant in plant foods and it is important to ensure intake of adequate amounts to support optimal health.
  o Vitamin B12
  o Vitamin D
  o Iron
  o Omega-3 essential fatty acids

Question 7

Vitamin B12:

Answer 7

Vitamin B12:
* Vegan / vege:
o Chlorella pyrenoidosa
o Nutritional yeast,S
o Sea vegetables (nori, kombu, kelp and dulse)
o Shiitake and Lion’s mane mushrooms.
* Vege:
o Cottage and feta cheese
o Eggs.

• N/B: Ensure good HCl production to improve available intrinsic factor needed for B12absorption

Question 8

Vitamin D

Answer 8

• Sunlight is the best source of vitamin D.
• Plant source:
  o Vitamin D2—in mushrooms (if good sun exposure).
• Egg yolks.
• Supplemental vitamin D may be necessary for some during the winter months —general recommendations: 5‒15 mcg or 200‒400 IU / day.

Question 9

Iron

Answer 9

• Plant sources (non-haem):
  o Dark green veg
  o Lentils
  o Pumpkin seeds
  o Quinoa
  o Oats
  o Chickpeas.
• Combine with vitamin C-rich foods to enhance absorption, e.g. peppers, cruciferous veg, kiwis, oranges, lemon.

Question 10

Omega-3 essential fatty acids:

Answer 10

• Vegetarians must rely largely on the conversion of alpha-linolenic acid (ALA) to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — the biologically-active forms.
• To support this conversion, avoid over-consumption of omega-6 fatty acids (abundant in plant oils) as OM-3 and OM-6 compete for the same enzyme — delta-6-desaturase. Ensure adequate intake of zinc, magnesium and vitamin B6 to support delta-6-desaturase activity.
• The richest plant sources of ALA are:
  o Chia seeds
  o Flaxseeds
  o Flaxseed oil
  o Hempseeds
  o Hempseed oil
  o Walnuts.