Zinc and selenium are important micronutrients required for the immune system to function effectively along with vitamins A, C, E, B6, B12, C, D, E and folic acid and the trace elements iron and copper.
Both insufficient and excessive intakes of zinc and selenium can have negative consequences on the immune status.
For the majority of people, low selenium intake is not a major issue. Whole-grains provide provide a more than adequate supply for vegans.
A serum selenium test shows a short-term status of selenium whilst red blood cell selenium reflects a long-term status.
Before consuming large amounts of selenium in foods or supplements, it is important to know the true status of your selenium.
B12 is a group of cobalt-containing vitamins. Hydroxocobalamin and cyanocobalamin are synthetic forms of vitamin B12. The two forms of vitamin B12 naturally occurring in foods are methylcobalamin and adenosylcobalamin. These forms are biologically equivalent.
B12 is produced by a number of different species of bacteria which is found in the soil, on the surface of some plants and some red and green algae.
Lack of vitamin B12 can have serious consequences as does high levels of homocysteine. Determining the status of vitamin B12 and homocysteine can be difficult and can be determined by measuring serum vitamin B12, homocysteine and methylmalonic acid (MMA).
A number of products contain riboflavin, pyridoxine, folate, B12 and methionine way in excess of dietary requirements in an attempt to resolve B12 metabolism problems.
Many magnesium supplements contain pyridoxine which is usually unnecessary and possibly detrimental.
Most people are under the impression that starchy foods such as bread and potatoes make you fat. This is not the case - unless you cover your bread and potatoes with high-fat foods such as cheese, butter or sour cream. Excess sugars and carbohydrates are stored as glycogen - not fats. Carbohydrates are not converted to fats. Animals, bacteria and fungi convert glucose to glycogen which is the form that glucose is stored. Except in abnormal, extreme conditions, carbohydrates are not converted to fat in humans. Fats make you fat - not carbohydrates.
It is not uncommon for people to claim that they have tried a vegan diet and it simply did not work for them. Not all vegan diets are healthy.
Much publicity is given to the longevity of the people of Japan and Okinawa (an archipelago that stretches from southern Japan to Taiwan). However, the population with the longest lifespan and the highest levels of health on the planet is the vegan Californian Seventh-day Adventists.
People are not predisposed to vegan diets or otherwise. When it comes to nutrition, we are pretty much the same – allergies being one significant difference.
Below are components of a healthy whole-food, plant-based diet. Many people on a unhealthy vegan diet are missing a number of important components of an optimal diet.
Iodine is a major component of the thyroid hormones, thyroxine (T4), and triiodothyronine (T3). They are based on the amino acid tyrosine. T4 contains four iodine atoms and T3 three iodine atoms. The only known function of iodine is for the production of the thyroid hormones. Excess iodine is secreted in the urine.
Thyroid hormones are required for normal growth and development of the brain and central nervous system. It is required for energy production and oxygen consumption in cells and the maintenance of the metabolic rate.
The regulation of thyroid hormone synthesis, release, and action is a complex process involving the thyroid, the pituitary, the brain, and peripheral tissues.
Sea foods and iodine added to table salt are the highest contributors of iodine to our diet which is why vegans often resort to supplementation which can have unintended consquences.