Protein is essential for the function and building of our physical body. When we are active, such as carrying heavy things, walking fast for thirty minutes, doing yoga asanas requiring retention of hand supporting weight poses; our muscles, including heart muscles experience stress and damage. Protein is needed to repair and build muscles and bones. Our immune system needs protein to build the T cells. Our body needs protein to produce enzymes to digest, to regulate functions properly.
Protein need of individuals has been a subject of debates. A 2010 review finding lead to a consensus that corrected up the previous need of 0.8 grams/ kg of bodyweight by 40% (1). For active people more protein is needed than sedentary ones. Athletes should follow the same recommendations as the general public.
Approximately 12%-15% of calories should be from protein, adjusting total calories based on physical activity (2). 10 g essential amino acids in the early recovery phase (0 to 2 hours after exercise) is important for proper muscle synthesis (Muscle protein synthesis/ MPS). (2).
A 2010 review recommends the protein requirement for athletes to be between 1.4 and 2.0 g/kg bodyweight/ day (3).
However, excessive protein consumption of more than 2 g/kg bodyweight can be harmful to calcium stores, kidney function, bone health, and cardiovascular health (4, 5, 6).
How to tell that you need more protein?
1. Hunger
Constant or frequent physical and or emotional hunger closely (less than 3 hours) after meals is a sign we do not provide enough protein for our body. Protein is needed to produce signals of satiety to the brain and stabilize blood sugar. Research found that protein induces satiety by activating gut nerve receptor. Lack of protein in diet triggers hunger (8).The induction of intestinal gluconeogenesis translates into a release of glucose in the gut portal vein, which collects blood from the whole gut. Its detection by a portal glucose sensor and the transmission of this signal to the brain by the peripheral neural system initiate a decrease in hunger and an improvement in the insulin sensitivity of hepatic glucose production. Important amino acids from protein are needed for many biological processes in the body as well.
2. Slow recovery after exercise and fatique
During exercise muscle protein broken down must be replenished by enough protein shortly after. A deficiency in protein can certainly lead to both muscle, nerve and brain fatigue. Inadequate protein can cause muscle wasting, then muscle cramps and fatigued muscle. Amino acids such as glutamine are used alongside glucose in the muscle for fuel. Amino acids are also needed to build neurotransmitters involved in cognitive function and memory.
3. Frequent infections
Protein is important in defense activation in response to infections. I experienced twice of pneumonia infections within 15 months. Together with other symptoms of protein defficiency of muscle loss diagnosis defend my position against a vegan promoter who insists that raw vegans and vegans require much less protein, a wishful thinking!
4. Depression
Amino acids such as tryptophan or tyrosine are precursors to neurotransmitters such as serotonin and dopamine. Inadequate protein can lead to depression and anxiety.
5. Sleep disturbance
Protein’s role in stabilizing blood sugar level as mentioned in 1 is important to maintain good and enough sleep along the night, rather than waking up hungry and tensed.
6. Hair loss and unhealthy dull skin
Amino acids such as cysteine, lysine, arginine and methionine are needed to form hair’s collagen and keratin. Lack of protein cause hair loss and dull skin.
7. Fluid retention
Protein is needed to maintain balance of fluid in and outside of the cells. Without enough protein, the body will retain fluid on the outside of cells causing fluid retention or edema particularly around the abdomen and dehydration of cell.
Do vegans and raw vegans need less protein?
The wishful thinking that vegans and raw vegans need less protein is somewhat unfounded. In fact vegans need more protein as plant protein bioavailability is lower because of the presence of fibre and antinutritions (9), (10). Raw vegans are even challenged by excluding protein fom beans and grains.
Resources for planning vegetarian/ vegan diet for infants, children and Adults
Protein and vegetarian diets
Marsh, K. A., Munn, E. A., & Baines, S. K. (2013). Protein and vegetarian diets. The Medical Journal of Australia, 199(4), 7-10.
https://drive.google.com/file/d/189FWuj-90pSR5fSw69hfP4uF0Mxeuc19/view?usp=drivesdk
Clinical practice. Vegetarian infant and child nutrition
Van Winckel, M., Velde, S. V., De Bruyne, R., & Van Biervliet, S. (2011). Clinical practice. European journal of pediatrics, 170(12), 1489-1494.
https://drive.google.com/file/d/1bA36Oc9N4F_fBRHUe4pIjKO-TZnL1-7n/view?usp=drivesdk
Considerations in planning vegan diets: Children
Messina, V., & Mangels, A. R. (2001). Considerations in planning vegan diets: Children. Journal of the American dietetic association, 101(6), 661-669.
https://drive.google.com/file/d/1CiL-pjoovnWeYYHMotc4BWgIIZmyNQdl/view?usp=drivesdk
You can read and download the articles from the links.
Healthy & Happy Melani Harriman 