The vegan diet has as main objective to obtain the necessary nutrients through food of vegetable origin only. That is, with the total elimination of meat in the diet.
Obviously this implies a great change not only in our eating habits but also in our body .
Since the origins of the existence of our species, meat has been present in the diet of our ancestors and without a doubt it has been thanks to it that man has been able to progress and survive the great changes of evolution .
People who decide to opt for a vegan diet are mainly driven by three fundamental reasons : for ethical reasons , in respect for the life of animals, environmental, because they defend the sustainability of the planet and for health, because they believe that eliminating meat and the fat containing their diets prevent diseases related thereto.
Motivations more than worthy to avoid the consumption of meat, but that also entails great disclaimers and health risks that are important and that must be taken into account.
THE VEGETABLES: SOURCE OF VITAMINS, MINERALS AND FIBER
By changing to an exclusively vegetarian diet like vegan, this provides great health benefits in many ways. In addition to fiber , vegetables offer large amounts of certain vitamins and minerals .
Vitamin A: it also exists in animals, the one from the plants must be transformed by the body to be assimilated and its effectiveness is less than that of animals. Despite this it offers an important advantage because it acts as an antioxidant. It is found in some vegetables such as carrots.
Vitamins B1, B2, B3, B5 and B6: in the vegan diet they do not pose a risk of deficit, since they are mainly present in whole grains and nuts .
Vitamin B7 (Biotin): its vegetable source is found in oats and hazelnuts , being lower in other vegetables.
Vitamin B9 (Folic acid): almost all vegetables, legumes and citrus fruits possess it, so it does not pose a risk of lack.
Vitamin B12: it is the most controversial of the vitamins in the vegan diet, since it is not found in any vegetable . In fact, they are not synthesized by animals or plants or fungi, but only by particular bacteria that live in the intestines of some animals and then accumulated in their meat.
It is also synthesized by Archaea , unicellular microorganisms with prokaryotic morphology similar to bacteria, which live in both aquatic and terrestrial environments .
In the oceans they are part of the plankton and constitute one of the most abundant groups of organisms in the life of the planet. They are found in hot springs, salt lakes and swamps as in the same land and also in the intestine of ruminants and even in the human colon .
A precursor of vitamin B12 is found naturally in some foods such as a particular type of algae due to bacterial symbiosis , but commercial production of vitamin B12 from this algae is delaying due to the complexity of its synthesis, its high cost and low profitability.
These microorganisms also form an important part in modern biotechnology in the synthesis of biogas and purification of the waters in which these algae are used.
The herbivores get vitamin B12 by eating the roots of plants and ingest earth with it, when licking their legs or eating up their own feces, as some animals do, like rabbits. While carnivores evidently consume it directly from the ingestion of meat .
The industrial synthesis of vitamin B12 is produced from bacterial fermentation .
Vitamin C: It is a powerful antioxidant and is present in abundance in fruits and vegetables.
Vitamin D: This vitamin is not present in vegetables , but our body can synthesize it if we are exposed to sunlight directly. Simply minimal exposure and also it accumulates in the body. Also some fungi synthesize it in the sun. The artificial ultraviolet light is also a good alternative option.
Vitamin E: is a powerful antioxidant and it found in large quantities in vegetables and nuts.
Vitamin K: It can be found in vegetables that perform photosynthesis and also synthesized by some bacteria in fermentations.
THE BENEFITS OF THE VEGAN DIET
The large contribution of vitamins, minerals, fiber and proteins offered by vegetables allows great health benefits.
Benefits in diabetes control: vegetable consumption lowers blood glucose . It is proven by scientific studies that a vegan diet significantly reduces glucose in the blood by promoting the development and control of insulin in patients with diabetes.
Benefits in anemia and pregnancy: the folic acid abundant in green vegetables contributes to the formation of red blood cells and DNA production, so it is used in the treatment of anemic conditions. In addition, together with vitamin B12 and C, it helps in the breakdown, use, creation and maturation of new proteins. In pregnancy it prevents malformations in the placenta and genetic in the fetus .
Immunological benefits in the system and antioxidant action: the vitamin C abundant in the vegan diet, is a potent antioxidant that promotes immunologic system, also prevents and slows the oxidation of cells and thus its aging .
Benefits in weight control: Also Vitamin C helps in dieting and healthy weight and cholesterol level control. Actively involved in the metabolism of lipoproteins, these stabilize lipids and blood cholesterol.
In addition, the lower consumption of calories and general fat in the vegan diet helps maintain a balanced weight and helps lower total cholesterol and LDL .
Vascular benefits: The vitamin C also helps to maintain endothelial integrity, strengthening the internal tissue of blood vessels and the heart, so prevents arteriosclerosis , the hypertension arterial, inflammation and stroke, hemorrhage, etc.
In addition, a low-fat diet such as vegan helps lower blood cholesterol , which helps prevent the vascular risk mentioned above.
Benefits for the joints : Rheumatic diseases such as osteoarthritis and arthritis are caused by joint wear, produce inflammation and pain, so many plant foods can relieve these symptoms , such as turmeric, ginger, oranges, raspberries, blackberries, olive oil and broccoli. Chard and spinach help also in the bones, they are high in magnesium and helps to fix calcium in the bones and better overall bone health. But you also have to keep in mind that certain vegetables from the Solanaceae family such as tomato, eggplant, potato or pepper are counterproductive.
Also a low-calorie diet such as vegan helps to maintain an adequate weight and avoid obesity which also helps to combat the negative symptoms of arthritis and osteoarthritis.
Benefits heartburn and laxative: the magnesium also acts on the intestinal flora favoring transit.
Benefits nervous system: The magnesium is considered a tranquilizer and natural relaxant , promotes sleep and acts as antidepressant and anti – stress agent. It is involved in the energy balance of neurons and nerve transmissions and in general in the neurological system. It is a powerful muscle relaxant and prevents premature births keeping the uterus relaxed.
Benefits in the hormone system: The magnesium is also involved in the hormonal system and reduces menstrual cramps.
As we have seen, there are many benefits of integrating plant products into the diet. But we must keep in mind that this wealth is not exclusive to the vegan diet , since the omnivorous also incorporates them in the same way and therefore this also takes the advantages it offers.
An adequate nutrition education in proportion and variety is the key to good mental and physical health , regardless of the type of diet.
The prevention of diseases through proper nutrition and a lifestyle consistent with age and circumstances is the best and the smartest way to maintain good physical and mental health.
HOW TO SUBSTITUTE MEAT PROPERLY BY VEGETABLES
The great challenge facing vegans is to ensure an adequate dose of nutrients with only the consumption of plant products.
As we know by being omnivorous , we are genetically predisposed to obtain the nutrients we need also through the consumption of meat . The total elimination of products of animal origin, can cause significant nutritional deficiencies if we do not adopt measures that require great discipline and awareness.
Acquiring adequate nutritional education and managing to insert it into our daily eating habits with responsibility is essential to maintain good mental and physical health. This premise is evidently valid for both vegans and meat consumers.
MAIN NUTRITIONAL FEATURES IN THE VEGAN DIET
Although a diet rich in fiber and vegetable proteins such as vegan offers great benefits, it can also cause significant damage and health risks that we must absolutely prevent.
In order to adequately replace animal products with vegetables, it is essential to determine which are the main deficiencies that can be detected in a diet exclusively of vegetables.
The elimination of all products of animal origin can cause important nutritional deficiencies , mainly of vitamin B12, D, calcium, omega-3 fat acids, iodine and often also iron, zinc and selenium .
The only way to prevent these deficiencies is to incorporate supplementary integrative foods . But you also have to keep in mind that animal proteins provide essential amino acids .
The most critical nutrient in vegan diets is vitamin B12 which in natural foods without additives is present in sufficient quantity for humans only in foods of animal origin .
In addition, it is necessary to consider and recognize that the foods consumed in the vegan diet are not necessarily promoters of good health or favorable from the nutritional point of view.
Despite these drawbacks, well-planned vegan diets can be rich in fiber, magnesium, folic acid (vitamin B9), vitamin C, E, potassium, as well as being lower in calories, saturated fat and cholesterol.
Obviously the foods that are richer in proteins and that are therefore carriers of essential amino acids in sufficient quantity for humans are those of animal origin : meat, fish, lactic products and eggs.
Although vegetables are a source of a smaller amount of essential amino acids , they are also a source of protein and as such also provide amino acids after digestion. A varied and sufficient intake of plant foods can meet the needs of proteins and amino acids.
However, the greatest doubts are the compensation in essential amino acids, since providing these essential amino acids only with vegetable proteins requires a strict discipline in eating habits.
The vegan diet proposes to consume a greater amount of vegetable protein (legumes, soybeans, grains, nuts and seeds) in order to compensate for this lack.
The main vegetable protein is found in legumes such as soy with which tofu, tempeh, textured vegetable protein, soy milk and edamame are made . Also in peas, cashews, beans and chickpeas (humus), quinoa, rice, corn, grain (whole grain, bulgur and seitan) and nuts such as almonds and seeds.
In addition, quinoa is rich in trace elements and vitamins . It exceeds in biological value , in nutritional and functional quality to the other traditional cereals , such as wheat grain, corn, rice or oatmeal and besides not containing gluten .
ESSENTIAL AMINO ACIDS OF VEGETABLE ORIGIN:
QUINOA AND SPIRULINA ALGAE
Among the plant foods described above, only quinoa is the only food of terrestrial plant origin that together with the spirulina algae contain and provide all 9 essential amino acids for nutrition and some more non-essential.
The major drawback for vegans is to ensure the necessary dose of essential amino acids from plants through the consumption of sufficient quinoa and spirulina algae.
The spirulina is a high protein food supplement , rich in vitamins, minerals and phytochemicals that also provides all 9 essential amino acids .
It is obtained from two species of algae , Arthrospira platensis and Arthrospira maxima , both are cyanobacteria , unicellular organisms known as ” blue algae “.
Keep in mind that spirulina contains a non-active substance, a precursor similar to vitamin B12 , but does not provide active vitamin B12 , so it cannot be considered as a reliable source of this vitamin.
NUTRITIONAL COMBINATIONS CONTRIBUTING ESSENTIAL AMINO-ACIDS
In the culinary tradition there are vegetable food combinations that provide some essential amino acids . In general the combination of legumes and cereals supply them. For example: rice with beans, lentils or peanuts, corn with beans or lentils, wheat with beans, humus with whole wheat and chickpeas with oats.
VITAMIN B12 IN THE VEGAN DIET
The lack of vitamin B12 in the vegan diet is surely the most controversial and most doubtful argument .
Vitamin B12 is essential for good health and the difficulty of finding it in an exclusively vegetable diet is unquestionable. Although there are synthetic alternatives that solve this lack .
Vitamin B12 is indispensable for cell division, the formation and maturation of red blood cells, for the synthesis of DNA and for the proper functioning of the nervous system. Its lack is a real danger to physical and psychic health, and very often vegans have a deficiency of this vitamin.
Its lack can cause megaloblastic anemia , early vascular alterations , risk of developing diseases related to arteriosclerosis and neurological disorders .
Too often the high folic acid content in the vegan diet hides the ematological symptoms of a vitamin B12 deficiency . For this reason it can go unnoticed until neurological symptoms are not developed in the last stages of the evolution of the disease. Reaching neuropsychiatric disorders, neuropathies, dementias and atrophy of irreversible optic nerves.
Introducing vitamin B12 into a vegan diet through food is really arduous, because only natural foods of animal origin contain enough vitamin B12 to meet the need of human beings.
In the vegan diet, covering this need for vitamin B12 is essential, so it is necessary to eat foods fortified with this vitamin and regularly consume vitamin B12 supplements .
PROVENIENCE OF THE VITAMIN B12
The difficulty of obtaining vitamin B12 lies in the fact that it is produced only by certain bacteria that live in the dirt of the soil, water, feces or grown in laboratories .
Neither plants nor animals are able to produce vitamin B12 . Only some animals such as ruminants and precisely also man contain it inside their intestines but are the only intestinal bacteria capable of synthesizing it.
Unfortunately, humans cannot absorb this vitamin B12 directly from themselves , because the synthesis occurs in the colon , away from the small intestine where absorption of this vitamin occurs. So we must acquire it from the outside , that is, through ingestion of it through food.
Interestingly , ruminants , such as cows and sheep, can absorb vitamin B12 from themselves , synthesized by bacteria found in their own intestines. These herbivorous animals obtain it from the bacteria found in their rumen , either by assumption or by ingestion of their own feces .
Animals store vitamin B12 in the liver and muscles , from which it also passes to eggs and in mammals also to milk . For this reason its meat, liver, eggs and milk are a source of vitamin B12.
ALTERNATIVE WAYS OF OBTAINING VITAMIN B12
The vitamin B12 is synthesized by certain bacteria as we have said, so plant foods are not reliable and adequate source of active vitamin B12.
In the vegan diet it is vital to obtain this vitamin through industrial synthetic preparations . Its preparation is obtained through the industrial fermentation of various types of bacteria that synthesize various forms of active cobalamines . This is processed to generate fortified nutritional and food supplements.
Only two cobalamines are active in the human body as coenzymes: adenosincobalamin and methylcobalamin .
The human body has the ability to convert some cobalamins into active forms of vitamin B12 .
There are 4 cobalamines that produce vitamin B12 (active and inactive) : adenosine-hydroxy-methyl-cyano cobalamin . But only 2 become active forms of vitamin B12 : cyanocobalamin and hydroxycobalamin .
There are other cobalamines that are not usable by human B12 enzymes. They are inactive B12 analogues , they are the combined ones: metyladenincobalamine and adenincobalamin .
Some algae such as spirulina , nori , wakame and chlorella , yeasts such as miso, ferments of kefir, may contain inactive cobalamines of vitamin B12.
The true active vitamin B12 is found in meats, eggs, dairy, supplements and fortified foods .
The industrial manufacture of vitamin B12 is produced through the fermentation of some bacteria such as Pseudomonas denitrificans, Propionibacterium freudenreichii and Propionibacterium shermanii , mainly.
Although lately the industries are adapting to the strong vegan demand synthesizing vitamin B12 without the use of animal products , there are still many that for the synthesis of vitamin B12 still use products of animal origin.
In addition, commercial vitamin B12 food supplements may contain animal-derived excipients in the form of gelatin or other substances.
Also the enormous commercial demand in recent years of vitamin B12 has caused the increase in the study and search for alternatives to find variants of vitamin B12 that can meet the dietary needs of vegan and vegetarian people.
This has undoubtedly caused an inconsiderate increase in animal experiments to find new sources and alternative methods of synthesis of such a vitamin.
VEGETABLE FOOD WITH CHOLINE
Although mostly animal products contain more choline , many plant foods are also a source of choline, for example wheat germ, soy lecithin, tofu, brussel sprouts, broccoli, cauliflower, spinach, quinoa, beans and amaranth.
VEGETABLE FOODS WITH OMEGA 3 FAT ACIDS
Nuts, avocado, olive, linseed and rapeseed oils, seaweed oil, hemp and flax seeds are sources of ALA, the precursor to DHA and EPA, omega -3 fat acids.
VEGETABLE FOOD WITH IODINE
In the vegan and vegetarian diet there is a potential danger of alterations due to iodine deficiency , since it is not guaranteed that the land where fruits and vegetables are grown have adequate and sufficient iodine levels.
For this reason the only reliable sources that ensure timely input are marine vegetables, iodized salt and iodine food supplements .