Protein - Animal protein, Excess Protein and Plant-based Protein:

Question 1

Animal Proteins

Answer 1

Whilst animal sources of protein contain all essential amino acids, high animal protein diets have the following negative effects:
* Methionine is an amino acid highly abundant in animal proteins and has an immune-stimulating effect on T cells, which is, if used in excess associated with over-reactive immune responses (autoimmunity and chronic inflammation). Excess methionine also increases homocysteine which is associated with atherosclerosis.
* Unless organic, can contain chemical residues. Occurs either by direct oral or topical dosing of the animal (e.g. pesticides to control lice and fleas) or exposure to crop pesticides in feed. If eating meat, focus on organic, grass-fed sources.

Question 2

Excess Proteins

Answer 2

• The adverse effects associated with high, long-term animal protein intake in humans include:
  o Osteoporosis
  o Kidney disease
  o Increased cancer risk
  o Disorders of liver function
  o Atherosclerosis
  o Increased muscle soreness post-exercise
• High protein is generally considered to be 20% of calorie intake or more.
• Alkaline rich fruit and vegetables buffer the protein derived acid load, so always encourage plant-based eating.

Question 3

Excess Proteins: Cancer

Answer 3

• Both high and moderate animal protein intake increases cancer risk significantly, and is linked to cancer initiation and promotion.
• WHO (2015) classified red meat as a probable cause of cancer; processed meats (salted, cured, fermented, smoked) are deemed carcinogens.
• High intakes of red meat (especially processed) are strongly linked to several cancers. Polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs) produced during the high temperature cooking of meat (e.g. frying, BBQ, high temp-roasting) are carcinogenic.
  Review the China Study for more info.

Question 4

Excess Protein: Skeletal Disease

Answer 4

• Due to the acidic burden of excess animal protein, it can also draw calcium out of bones and increase the risk of osteoporosis.
• However, because of the collagen structure within bone, a protein deficiency can also negatively impact bone health.

Question 5

Excess Protein: Kidney Disease

Answer 5

• The extra acidity from a high animal protein intake needs buffering by the kidneys.
• The kidneys must also filter the increased urea that is generated.

Question 6

Excess Protein: Cardiovascular disease

Answer 6

• Associated with oxidation and inflammation in the endothelium.

Question 7

Plant-based Protein Benefits

Answer 7

Various Research, including the China study found that:
* Restriction of high levels of specific amino acids found predominantly in meat (methionine and branch chain amino acids) appears to be beneficial to health.
* Plant-based proteins from sources such as peas, legumes, wholegrains, nuts and vegetables are protective against cancer, autoimmunity, diabetes mellitus and cardiovascular disease. This is likely due to the presence of health-supporting fibre, phytonutrients and prebiotics.
* Plant-based proteins assist healthy ageing with their lower levels of the essential amino acid leucine (in higher amounts in animal proteins), which can increase the expression of the enzyme TOR.
TOR= “Target Of Rapamycin” –an enzyme that regulates cell growth