All nutrients essential for optimal health and sports performance can be supplied by a plant based diet with no additional requirements from animal sources. This is quite a contentious statement and in the following series of articles the team and I at SSC will seek to dispel any myths and shed light on points of dispute regarding plant based diets.
Ensuring all nutrient needs are met, consistently, by a plant based diet cannot happen by accident. Just by omitting all animal products and eating more of what you would normally eat outside of them will not usually satisfy all minimal daily amounts. For optimal health a wide variety of plants, nuts, seeds, grains, beans, pulses and fruits need to be consumed regularly. For improved sports performance a properly constructed and strategically managed individualised program must be followed and this program must be periodised to reflect the different demands, certainly in energy requirements, over the year.
In Part 1 of this series on vegan nutrition we look at a selection of nutrients essential for health and performance. The selection is limited to those nutrients that are commonly thought of as being deficient in the vegan diet however evidence suggests these nutrients are also deficient in omnivorous diets as well. With that in mind this article will serve as a useful guide not just to vegan athletes but to flexitarian, vegetarian and omnivorous ones too.
We have used technical reports from the World Health Organisation, peer reviewed scientific articles from the best sports nutrition journals and results from our own tests as our evidence base. Our nutrient intake recommendations have taken into account nutrient loss during cooking and digestion. Certain mineral and vitamin availability is compromised in the presence of other minerals and vitamins particularly with Iron and Zinc and recommendations will be made in Part 2 regarding food combining to enhance bioavailability and food avoidance to reduce likelihood of nutrient inhibition.
There are 9 amino acids that human beings cannot synthesize and are termed essential amino acids. A regular intake of these protein builders is vital. Some essential amino acid intake recommendations are, by their presence in common foods, easier to meet than others. We do not have the facility to store these amino acids in any large number so it is important for the vegan athlete to keep a regular eye food intake so the food groups containing these amino acids are regularly consumed.
Recommended intakes are provide per kg of body weight enabling the prescription to be more personalised both between athletes and during changing body composition values found transitioning from in-season/in-competition periods to off-season training.
Histidine 10 mg.kg.day-1
Found in most plant based proteins, particularly wheat germ, histidine is intricately involved in a wide range of critical metabolic processes including regulation of antibody activity and production of red and white blood cells. Histidine also helps maintain the myelin sheaths which surround and insulate nerve cells and is the primary building block of histamine. From a sport and performance perspective histidine possesses vasodilating and hypotensive actions regulating blood pressure and circulatory responses to exercise.
PLANT BASED FOOD SOURCES: Tofu; Haricot beans; Pumpkin seeds.
Isoleucine 20 mg.kg.day-1
A branched chain amino acid, so called due to the molecular design, necessary for haemoglobin formation as well as stabilising and regulating blood sugar. Deficiencies of this amino acid are not uncommon particularly in the elderly and symptoms include muscle wasting, tremors and a feeling of low energy.
PLANT BASED FOOD SOURCES: Tempeh; Seaweed; Spirulina.
Lysine 30 mg.kg.day-1
Essential for proper growth and development Lysine plays an essential role in sport and performance as it aids calcium absorption, the formation of collagen necessary to build and repair muscle protein, connective tissue, skin and cartilage. Lysine also enhances the immune system aiding in the production of antibodies, hormones and enzymes. Lysine deficiency can present as irritability, loss of energy, retarded growth and hair loss amongst other issues.
PLANT BASED FOOD SOURCES: Seaweed; Spirulina; Tofu.
Leucine 39 mg.kg.day-1
Leucine stimulates protein synthesis in muscles, and is essential for growth. Leucine also promotes the healing of bones, skin and muscle tissue. Leucine, and the other branched-chain amino acids (BCAAs), Isoleucine and Valine, are frequently deficient in the elderly, and increased body requirements can occur after trauma or surgery.
PLANT BASED FOOD SOURCES: Brazil nuts, Lentils; Sesame seeds; Tempeh.
Methionine 15 mg.kg.day-1
One of the sulphur containing amino acids, Methionine is important in many body functions. Through its supply of sulphur, it improves the tone and pliability of the skin, conditions the hair and strengthens nails. The mineral sulphur also protects the cells from airborne pollutants, such as smog, slows down the aging process in the cells, and is involved with the production of protein.
Methionine is essential for the absorption and transportation and bioavailability of selenium and zinc in the body. It also acts as a lipotropic agent to prevent excess fat buildup in the liver, and is an excellent chelator of heavy metals, such as lead, cadmium and mercury, binding them and aiding in their excretion from the body.
PLANT BASED FOOD SOURCES: Brazil nuts, Sesame seeds, Sunflower seeds.
Phenylalanine 25 mg.kg.day-1
Phenylalanine is a precursor of tyrosine, and together they lead to the formation of thyroxine or thyroid hormone, and of epinephrine and norepinephrine which is converted into a neurotransmitter, a brain chemical which transmits nerve impulses. This neurotransmitter is used by the brain to manufacture norepinephrine which promotes mental alertness, memory, elevates mood, and suppresses the appetite very effectively.
Phenylalanine deficiency can cause bloodshot eyes, cataracts and behavioural changes.
PLANT BASED FOOD SOURCES: Peanuts; Sesame seeds, Sunflower seeds.
Threonine 15 mg.kg.day-1
It is an important constituent in many body proteins and is necessary for the formation of tooth enamel protein, collagen and elastin. Some research suggests biosynthesis of nutrients is enhanced in the presence of threonine.
PLANT BASED FOOD SOURCES: Baker’s yeast; Tofu; Wheat germ.
Tryptophan 4 mg.kg.day-1
Linked to low serotonin levels resulting in insomnia, anxiety and depression, Tryptophan is the least abundant amino acid in proteins and also easily destroyed by the liver. Tryptophan is necessary for the production of the B-vitamin niacin, which is essential for the manufacture of the key neurotransmitter serotonin. It helps control hyperactivity, relieves stress, suppresses the appetite and enhances the release of growth hormones.
From a sport and performance perspective Tryptophan can assist in reducing the effects of jet-lag on performance and reaction times as well as assisting those suffering from insomnia.
PLANT BASED FOOD SOURCES: Chia seeds; Pumpkin seeds; Sesame seeds.
Valine 26 mg.kg.day-1
Valine has a stimulant effect. Healthy growth depends on it. A deficiency results in a negative hydrogen balance in the body.
Valine has many neurological uses, it can be metabolized to fuel neural cells in the brain, assists in neurotransmitter systhesis and helps maintain the myelin covering of the nerves. Deficiencies may increase the likelihood of degenerative neurological conditions.
PLANT BASED FOOD SOURCES: Seaweed; Spirulina; Tofu