Vegetarian diet / how to do it properly

The  vegetarian diet  is a type of diet that excludes different or all  animal products  or their processing. The Italian vegetarian  term is used in the literature to indicate all the variations of the plant-based diet. It therefore includes:

• The lacto-ovo-vegetarian model  ( LOV ): based on the consumption of cereals, legumes, vegetables, fruits, nuts , oilseeds, dairy products, eggs , and excludes meat, fish, molluscs, crustaceans and derivatives. This is also the most widespread model in Western countries.
• The lacto-vegetarian  model ( LV ): similar to the LOV model but also excludes eggs. This is more common in India.
• The ovo-vegetarian  model ( OV ): similar to the LOV but excludes milk and derivatives.
• The vegan model : based exclusively on the consumption of foods of plant origin. It therefore excludes all foods of animal origin and its derivatives.

VEGETARIAN DIET	MEAT	FISH	MILK AND DERIVATIVES	EGGS
Lacto-ovo-vegetarian	No	No	Yup	Yup
Pescetariana	No	Yup	No	No
Lacto-vegetarian	No	No	Yup	No
Ovo-vegetarian	No	No	No	Yup
Vegan	No	No	No	No

Today we can safely say that a vegetarian diet (including the most extreme model, vegan) helps maintain a person’s health, although in some cases it is recommended to support supplementsfood (supplements still often use also omnivores).

Balanced vegetarian diet

The vegetarian diet is not healthy regardless. In fact, an unbalanced and inadequately planned diet can also result in a diet that provides for the consumption of only plant foods or the exclusion of certain foods of animal origin; just as an omnivorous diet can be harmful  (and we have infinite examples).

In 1997, on the occasion of the Third International Congress on Vegetarian Nutrition , held on the campus of the University of Loma Linda in California , the first guidelines for vegetarian nutrition were formulated. In the following years, various changes were made, keeping pace with new scientific evidence.

The Nutrition Guidelines  can be graphically illustrated in food pyramids , through the division of these into several steps, each representing one of the main food groups that should always be present in a healthy vegetarian diet .

The most important are based on the Vegetarian Guidelines  produced by the USDA , Mayo Clinic , Academy of Nutrition and Dietetics or Loma Linda University .

The caloric distribution between the various groups of macronutrients varies not only according to the Guidelines considered but also according to sex, age and physical activity. Generally, in lacto-ovo-vegetarian  and vegan diets , the intake of carbohydrates, lipids and protides with respect to the total caloric intake is broken down as indicated in the table:

Breakdown of macronutrients in vegetarian diets. From “Project Diet Volume II” (Esposito D. 2017).

In 2005 they were created by the Scientific Society of Vegetarian Nutrition  ( SSNV ) of the Guidelines for Italian vegetarians, whose last version dates back to 2010. The criteria are:

• Consume large quantities and variety of foods.
• Privilege unrefined and poorly processed foods.
• Consumption of milk and eggs is optional.
• Choose carefully and limit fats.
• Take good sources of omega-3 fatty acids.
• Take adequate amounts of calcium and vitamin D .
• Take adequate amounts of vitamin B12.
• Consume generous amounts of water and other liquids.

Vegetarian diet contraindications

Going to exclude meat and fish, are you really in danger of some deficiencies of vitamins, minerals, essential fats and proteins? Let’s find out.

Vegetarian diet and proteins

It has long been believed that animal proteins are better  than plant proteins because the former have a complete amino acid profile  and therefore can be used more easily for protein synthesis (which then protein synthesis in the common meaning means increase in muscle mass, but this is not always the case). According to various experts, the proteins of plant origin would allow only for a short initial period the growth and maintenance of muscle mass as they would not contain in sufficient quantities some essential amino acids , unlike animal proteins.

First of all, there is no scientific evidence that confirms the theory according to which a diet without animal proteins (therefore vegetarian or more precisely vegan) leads to loss of muscle mass or does not make it possible to increase or maintain it , also because this depends on more factors and primarily the total daily and weekly amount of protein, rather than the origin; in addition to exercise practice with adequate hypertrophic stimuli.

Epidemiological and observational evidence also tells us that a vegan diet does not create particular problems for an individual’s nitrogen balance. If anything, this type of vegan diet has other nutritional problems, but this is not the right paragraph to discuss it.

Trying to investigate the issue of proteins , I would like first of all to point out that the essential amino acids  are synthesized by the plants in origin; in fact, the herbivores take them from the vegetables. This should lead us to reflect on the fact that, perhaps, it is not only the ” quality of the protein ” that is the quantity  of the protein  intake and the food context (hypo-normo-high-calorie) that makes the difference. As we know, proteins are made up of amino acids : what interests us are amino acids, rather than proteins. When we ingest and digest proteins, we absorb the amino acids that comprised them.

Our body can use these amino acids for the synthesis of new proteins. The fundamental point is that our body does not have the ability to synthesize all twenty amino acids necessary for the biosynthesis of new proteins and, therefore, the amino acids that can not be synthesized by our fist are called essential amino acids  and must necessarily come with the diet . When an essential amino acid is missing, even if all the other amino acids are present, protein synthesis stops , since our body can not produce the essential amino acids and therefore can not continue in the synthesis of proteins.

The Liebig’s Law  states that growth is controlled not by the total amount of available natural resources, but the availability of the most poor. In fact, animal proteins, unlike vegetable ones, have a better amino acid profile which translates into a greater quantity and ratio between the essential amino acids, and this is the reason (or one of the reasons) for which they are preferred with respect to plants. . So far everything is correct, it is clear that animal proteins are superior to those of plants.

But we lack the latest information to be able to then build a reasoning that relies on scientific bases and not on rumors handed down over the years in the dressing rooms of gyms: amino acids have hematic emissions  of several hours , that is, even if they can not be deposited and then if not used in protein synthesis they must be either used for energy purposes or stored as fat.

Extending the discussion, therefore, what interests us is not the amino acid composition of the proteins of the single food that we eat and, possibly, of our single meal (which perhaps provides proteins mainly of a plant nature), but rather the total income of proteins taken in more meals during the day . In fact, we can take more plant proteins from different sources in the same meal or more meals during the day in order to obtain a complete amino acid pool that is suitable for protein synthesis . And this is the secret of vegans.

That’s why the guidelines that suggest to combine legumes with cereals are born, since the former are rich in lysine but poor in cysteine ​​and methionine and the latter are rich in cysteine ​​and methionine but poor in lysine. Another good indication is to combine plant proteins with animal proteins. Also in this case there are the various pseudo-experts who scream scandalized when they hear that they are combining different protein sources. Obviously this indication is not based on any scientific basis.

The plant proteins must therefore be considered in the daily protein quota exactly like the animal ones , although they do not have the same digestibility and the amino acid profile is incomplete. There is no reason not to consider plant proteins, the latter can contribute to protein synthesis as long as they are, during the day, through the composition and sequence of meals, combined with each other or with animal proteins to obtain the pool amino acid necessary for protein synthesis.

Rather, the differences analyzed earlier suggest that taking more proteins of animal origin may allow us to introduce less protein in general, while a vegan, for specific objectives such as those of maintaining muscle mass in a period of weight loss, or muscle hypertrophy during period of weight gain, will need to consume a slightly higher amount of protein than those who have an omnivorous or predominantly carnivorous diet.

Usually vegan athletes refer to the guidelines for the general protein quota: 1.6-2.5 g / kg of weight (lean mass if the subject has a high percentage of fat). With the awareness of being able to reach and / or exceed 3 g / kg for short periods.

As we can see the range is very wide, so you do not even need to “rework” the guidelines specifically for vegans, simply the latter will tend to position themselves towards the high end (from 2g / kg onwards) also helping with the protein supplements or by taking EAA  ( essential amino acids ). For the general population it is suggested a contribution of about 1g / kg: an amount perhaps too low, but that is shared with the omnivorous population.

Vegetarian and fat diet

In general, a vegan diet involves a reduction in lipid intake. However, this usually does not adversely affect the nutritional status of the adult or even the growth of children. In fact, the reduction of lipid intake is explained by the reduction of a large part of saturated or industrially hydrogenated foods. There are many foods, such as walnuts , dried fruit in general, seeds, avocado and vegetable oils that ensure an adequate lipid supply even in a vegan diet. What is there to be considered is the possible reduced intake of fatty acids of the omega 3 series , especially contained in fish, seafood and even in eggs.

It goes without saying that while a vegetarian may not have problems, in vegan a high omega 6/3 ratio could enhance the “inflammatory” characteristics of the diet due to the consequent greater formation of pro-inflammatory cytokines . Nothing serious or irremediable, attention: simply consider the inclusion of sources of alpha-linolenic acid  (omega 3), such as flax seeds (good vegetable sources too often neglected, even by vegans), although generally plant products have a higher ALA  content and reduced EPA and DHA . In addition, it is recommended to take food supplements.

The table shows the fatty acid content of some oils and the omega 6/3 ratio.

Fatty acid content and omega 9/6/3 distinction in some seeds / fruits. From “Project Diet Volume II” (Esposito D. 2017).

Vegetarian diet and vitamin B12

In 1926 GR Minot and WP Murphy showed that the liver contains an active ingredient that can treat pernicious anemia . Only in 1948, after a long series of unsuccessful searches, the English EL Smith and the Americans EL RIckes and K. Folkers managed to isolate and crystallize the anti-pernicious substance  which was given the name of vitamin B12 .

Therefore, vitamin B12 deficiency can cause neuropathy due to progressive demyelination of nerve fibers. Frenkel has shown defects in the fatty acids that make up the myelin sheath of neurons .

Alcune persone credono che l’assunzione di acido folico basti a risolvere la questione. In realtà ciò è errato: l’assunzione di acido folico, in effetti, migliora il quadro clinico dell’anemia megaloblastica associata a carenza di vitamina B12, ad eccezione, però, delle disfunzioni neurologiche. Peraltro, l’apporto di tale sostanza può mascherare la carenza di vitamina con la conseguenza di causare un aggravarsi della degenerazione del tessuto nervoso.

Il test utile per diagnosticare la carenza di questa vitamina riguarda l’esame dell’acido metil-malonico nelle urine, esame che consiglio di fare, in via preventiva, soprattutto ai vegani. Ma veniamo al punto: davvero il regime vegano è poco salutare in virtù di questa eventuale carenza?

La risposta è assolutamente ed inevitabilmente no. Questa ipotetica carenza, non rappresenta sicuramente un motivo valido per ritenere che il regime vegetariano o vegano sia pericoloso per la salute. In effetti, non vi è dubbio che un’alimentazione che esclude alimenti animali, principali fonti di vitamina B12, metta maggiormente a rischio di carenza i soggetti che la seguono. Il motivo è che questa sostanza viene sintetizzata solo da alcune specie di microrganismi e quella derivante dal microbiota non è del tutto assorbibile in quanto prodotta ad un livello in cui non è disponibile il fattore intrinseco (una glicoproteina secreta da alcune cellule gastriche necessaria per il suo assorbimento.

The point is that if we went to consult any university text of nutrition we would see that this provides two valid reasons why the insufficient intake of vitamin B12 is a very rare cause of avitaminosis :

1. Because the vitamin is widespread in foods of animal origin (and this does not help us, since we speak of vegans).
2. Because the deposits in the organism are so high that it takes several years to be exhausted (and this helps us to understand why millions of vegans do not get sick within 6 months or 1 year).

The reason why many vegans, even if they do not integrate vitamin B12, find themselves perfectly healthy and without apparent shortcomings, is that it takes several years to establish a specific pathological picture. This means, however, that integration will be necessary later.

In any case, algae  are a form of intake of cobalamin (vitamin B12) in the diet of vegetarians because they are contaminated by some microbial forms. Beware, spirulina , a common algae micro-organism, is not useful in this case because it synthesizes a form of cobalamin that can not be used by the human organism. In addition, a vegetarian diet can still provide adequate levels if you eat  fortified foods such as some cereals and soy drinks  .

In conclusion, vegans must supplement vitamin B12 , taking either fortified foods or special supplements. In most cases, with regard to vegans that were previously omnivorous, the B12 reserves mean that the shortage occurs only after several years.

Vegetarian and iron diet

The  iron  is actually contained in different plant foods, so it’s not exclusive to meat. However, the iron present in the meat is easily absorbed (iron heme, Fe ++) while the vegetable iron is often found as more oxidized iron (Fe +++) which is more difficult to assimilate and is often accompanied by antinutrients such as oxalic acid or phytic acid, which form insoluble complexes. It is not by chance that the guidelines for iron intake levels are different between omnivores and vegetarians / vegans, precisely because of the lower availability of this mineral in plant foods:  14-33 mg  for vegetarians and  8-18 mg  for omnivores . Also in this case, however, supplementation can be evaluated, checking the levels by blood analysis, even if it is not always necessary (read the article on foods rich in iron ).

The foods rich in vitamin C promote the absorption of iron, whereas phytates , the tannins and dietary fiber ,  inhibit it. Keep in mind that vegans, consuming an important amount of plant foods, generally have a higher intake of vitamin C than omnivores and, this, together with the fact that many plants have, even if with reduced bioavailability, a higher iron content than Many animal foods mean that most vegans do not have to worry about particular shortcomings of this nutrient.

Vegetarian diet and zinc

The  Zinc is an important mineral, necessary for good immune system function, wound healing and muscle recovery.

Indeed, plant foods contain little bioavailable zinc, especially in the case of high intake of phytates (significantly contained in both whole grains and legumes). Also in this case, therefore, it is advisable to feed 40% to 40% more than normal food.

The lacto-vegetarians  can resort to the consumption of cheese to increase the supply of zinc while the vegans can use, in addition to the legumes, the dried fruit and products made from fermented soy .

Vegetarian diet and vitamin A

There is reason to think that a meatless diet can be low in vitamin A . However, this can easily be avoided considering the consumption of foods rich in carotene (therefore precursors of vitamin A, which lead to the same end), therefore, consume all those vegetables orange, yellow, and those leafy, in addition to fruit .

In short, there is no real reason to think that a vegan can suffer from a lack of vitamin A (which is also fat-soluble and therefore does not need to be introduced daily) by following a proper diet.

Vegetarian diet and calcium

The  calcium  is essential in bone and muscle contraction health. In plants it is found mostly in green leafy vegetables, but they are rich in oxalates which reduce their absorption. If you consume fortified foods such as soy drinks or cereals, it is more difficult to be deficient, in fact, however, should be evaluated supplementation if these foods do not reach an average of about 1000mg of calcium per day.

Vegetarian diet and vitamin D

If already on an omnivorous diet , most adults are deficient in vit.D3, with a vegan diet the effect is amplified. Vit.D3 is necessary for bone health, but being a hormone also has many other functions. If you could expose yourself to the sun every day for 20-30 ‘few adults would be deficient, in any case it is a good idea for anyone supplementing it.

Vegans should look for a vitamin D3 obtained from vegetables, such as lichens, because it is often obtained from lanolin (sheep’s hair fat); Vitamin D2 should be avoided as it is not very functional.

Vegetarian diet for sportsmen

As we have seen, it is quite easy to avoid deficiencies due to the exclusion of meat and fish, and a  vegetarian diet for sportsmen  can be implemented without too much compromise.

Supplementation of creatine will be considered in addition  , because the liver, alone, produces little, and serves to improve performance and recovery. The proteins will be kept according to the  protein requirements , and possibly supplemented, for example, with whey protein (for lacto-ovo-vegetarian), which have a high biological value, excellent digestibility and very advantageous cost / protein ratio. For vegans the sources described above are good: soy, pea, etc.

Given the greater quantity of fiber linked to plant foods, it may be necessary, in order to improve absorption and decrease the digestive commitment, consume fewer sources of wholemeal and more “refined” carbohydrates such as white rice, the simple semolina pasta , potatoes and possibly use carbohydrates in powder such as maltodextrin, for example.

Vegetarian slimming diet

A vegetarian diet can also be useful for weight loss: the greater quantity of vegetables and fibers introduced favor satiety, but in any case to lose weight it is necessary to establish the caloric deficit, ie follow a  low-calorie diet . The measures are the same as any other diet, in addition to take into account any deficiencies discussed earlier.

Vegetarian protein diet

If  protein diet means  ketogenic diet , it’s not too difficult to set, because the exclusion of the meats are still eggs, dairy products, cheese, dried fruit etc … that provide both proteins fats with very few carbohydrates.

If instead we mean a  modified protein fasting diet (PSMF, VLCD), it becomes very difficult if it is not supplemented with  protein powder : the choice of food would be too narrow, since you can consume only lean protein sources and no carbohydrates (the lean meat, white fish, egg white and powdered proteins are the ideal prototype).

Example vegetarian diet for sportsmen

Breakfast	Semi- skimmed cow’s milk or soy drink 200g Oat flakes   70g Berry fruit 100g Honey or fruit jam 20g Flax seed 10g Whey or soy protein isolate 30g
Snack	Grain bread 50g Peanut butter 30g Apple 150g
Lunch	Pasta with tomato sauce 120g Oil with EVO 15g Egg and egg omelette 200g + 2 eggs or 2 soy burgers 200g Zucchini, carrots and boiled potatoes 100g + 100g + 100g
Post workout snack	Rice cakes 40g Banana or other fruit 150g Semi-skimmed cow’s milk or soy drink 150g Whey or soy protein isolate 30g
Dinner	Rice with peas 100g + 100g Mozzarella with reduced fat content 125g or natural tofu 300g Nuts 10g Salad tomato 150g + Lettuce 80g Oil EVO 15g
Integration	3-5g of creatine monohydrate, at any time 1 multimineral multivitamin for breakfast or lunch if vegan add: vit.B12 as needed, calcium citrate, vitamin D3

Vegetarian weekly diet

Monday	Breakfast:1 cup prazially skimmed cow milk + 40g whole grains Lunch : 60g Semolina pasta + 30g of dried beans 200g of boiled spinach + 30g grana cheese 10g of EVO oil Snack : 1 kiwi + 3 shelled walnuts Dinner: mix with tomatoes, lettuce, corn and wholemeal bread with 2 egg omelette 10g EVO oil
Tuesday	Breakfast:1 cup fortified soy drink, cocoa flavor + 5 whole rusks Lunch : 80g Semolina pasta 200g of boiled green beans + 150g lean ricotta 10g of EVO oil Snack : 1 banana + 6 almonds Dinner: 300g of boiled potatoes 1 vegetable Hamnburger 10g EVO oil
Wednesday	Breakfast:1 white skimmed yogurt + 20g jam + 20g blown cereals Lunch : Chickpea burgers made with 240g of canned chickpeas + 30g flour +1 egg200g Baked fennel 10g of EVO oil Snack : 1 slice of bread + 1 tablespoon of pistachio butter Dinner: Vegetable soup with beans and potatoes Toasted whole wheat croutons and grana cheese 10g EVO oil
Thursday	Breakfast:Oat porridge with frozen berries (30g + 100g) Lunch : 250g potato gnocchi with 4 cheeses Mixed salad with tomatoes, lettuce, carrots and corn 10g of EVO oil Snack : 1 fruit yogurt Dinner: 60g rice noodles 100g smoked tofu 100g savoy cabbage + 100g cauliflower + 30g stir-fried bean sprouts 10g EVO oil
Friday	Breakfast:1 cup prazially skimmed cow milk + 40g whole grains Lunch : 60g saffron risotto 125g cow’s milk ricotta 200g broccoli boiled 10g of EVO oil Snack : 1 apple + 3 shelled walnuts Dinner: 1 wholemeal sandwich with egg whites egg whites 100g + 1 egg + 200g zucchini 20g grana cheese 10g EVO oil
Saturday	Breakfast:2 wholemeal pancakes + 20g jam Lunch : 60g Semolina pasta + 30g of dried beans 200g of boiled carrots + emmental cheese 30g 10g of EVO oil Snack : 1 apple + 3 shelled walnuts Dinner: 1 vegetarian pizza (tomatoes mozzarella vegetables)
Sunday	Breakfast:2 wholemeal pancakes + 20g jam Lunch : soup with a box of beans 240g + semolina pasta 30g Mixed salad 10g of EVO oil Snack : 1 orange + 4 shelled peanuts Dinner: 3 Cannelloni with ricotta and spinach Salad of tomatoes 150g and mozzarella (1/2)