The interest in the vegetarian diet has increased a lot in recent years, also thanks to the stir caused by recent events such as avian flu, the so-called “mad cow” disease, the relationship between red meat and tumours, or repeated episodes of animal abuse in intensive farming.
Many people adhere to this dietary model driven by ideological considerations, others only because they consider it an effective and healthy diet.
The vegetarian diet has ancient roots and, as we said, the motivations that push a person to adopt it can be many (religious, ethical, economic, ecological, healthy, etc.).
In this article we will focus mainly on the health aspect, analysing the merits and defects of vegetarian diets and proposing some examples of properly balanced vegetarian menu.
We will start by specifying the various vegetarian diets.
Vegetarian Diet Types
How many types of vegetarian diet are there?
In the common imagination, we often understand the vegetarian diet as a simple diet without animal products. In reality, the concept is much broader, since in the large family of vegetarianism can be included different dietary models; let’s see them.
Dairy-Egg Vegetarian Diet
The dairy-egg-vegetarian diet allows you to feed on vegetables, microorganisms (mould and bacteria) and foods derived from animals, such as eggs, milk, cheese and honey. It excludes the consumption of meat and fishery products (including molluscs and crustaceans).
Attention! We should remember that we get some cheeses with the addition of rennet of animal origin (calf stomach enzymes); as such, we should exclude them from any vegetarian regime.
Many dairies farms have adapted to the needs of vegetarians by replacing animal rennet with vegetable rennet.
The dairy-vegetarian diet also excludes eggs, but milk and derivatives are allowed; the consumption of honey is at discretion.
The egg-vegetarian diet also excludes milk and derivatives but not eggs; the consumption of honey is at discretion.
The vegan diet renounces all products that involve animal involvement, including eggs and derivatives, such as dairy products and honey. It represents the vegetarian diet “in the strict sense”.
Remember that the vegan philosophy does not allow any animal involvement for the benefit of the human being. This also excludes the use of wool and silk for clothing, drugs got through animal experimentation, and certain fertilisers used in agriculture (especially blood, bone and horn meal, and fish).
Using manure is controversial, since the suitability depends on the origin (it is to be excluded the one deriving from farms), and some vegans do not admit the biological fight in cultivation (which is based on the biological antagonism of some organisms, entomological traps, etc.).
Raw Food Diet
It is a vegan diet based only on the consumption of raw or processed fruits and vegetables at temperatures not exceeding 40°C.
It is a vegan diet that allows only the consumption of fruits: flesh (apple, pear, orange, bell pepper, tomato, eggplant, zucchini, melon, watermelon, pumpkin, etc.), oilseeds (walnuts, hazelnuts, pine nuts, pistachios, almonds, etc.) and sprouted seeds (alpha, soy, carrot, barley, peanuts, etc.).
It is a vegan diet similar to the traditional one, but requires the consumption of only vegetable foods from organic or bio-dynamic crops.
Benefits Of The Vegetarian Diet
According to its supporters, the vegetarian diet (in all its types) is able, alone and without supplements, to meet the recommendations for all nutrients. As we will see later, this is a questionable statement. It can have a positive metabolic impact and in some ways promote the maintenance of health. Let’s see how.
What are the benefits of vegetarian diets?
A balanced vegetarian diet, combined with a healthy lifestyle, can reduce the risk of these diseases related to the modern lifestyle:
- Overweight and obesity
- Diabetes mellitus type 2
- LDL hypercholesterolemia (bad cholesterol)
- Vascular Diseases
- Some forms of cancer
- Overweight and obesity
The vegetarian diet is not always related to a normal body mass index. Many disorganised and poorly managed forms of vegetarianism can promote overweight.
This is the case with nutritional regimes that are mainly based on the consumption of white bread and pasta, potatoes, fatty cheese, oilseeds and seasoning oils in abundance. In contrast, vegetarian diets rich in fresh vegetables and the right amount of fruit, cheese, eggs, cereals, oils, oilseeds and tubers should favour the maintenance of a BMI between 18.5 and 25.0 (normal).
Diabetes mellitus type 2 and hypertriglyceridemia
We associate these two metabolic imbalances because triglycerides in the blood increase because of hyperglycaemia, the characteristic factor of type 2 diabetes mellitus and pre-diabetes.
Not all vegetarian diets are preventive against type 2 diabetes, mellitus and hypertriglyceridemia.
Only those rich in fresh fruits and vegetables, cereals and wholegrain derivatives, and unskinned legumes are considered beneficial.
Monothematic vegetarian diets based on cereals and refined derivatives can cause an increase in glycaemia, triglyceridemia and promote the onset of diabetes (as well as overweight).
Vegetarian diets, especially vegan diets, significantly lower LDL and total cholesterol.
This is because of the scarcity of cholesterol and saturated fats in the food consumed, but also to the richness of beneficial fatty acids (especially the essential polyunsaturated omega 6 linoleic acid) and other nutritional factors that have a positive metabolic impact (polyphenolic antioxidants, vitamins A, C, E, plant lecithins and phytosterols).
Vegetarian diets that include fried foods and belonging to the junk food category (sweet and salty snacks) are characterised by the abundance of tropical oils (tendentially saturated) and/or hydrogenated fatty acids (which have the same metabolic impact as saturated ones).
The exclusion of preserved meat and fish (cold cuts, sausages to cook, canned tuna, etc.) has a positive effect on the onset of sodium-sensitive hypertension. In addition, the essential omega-3 essential polyunsaturated fatty acid alpha linolenic acid, abundant in certain oilseeds and oils, has a marked hypotensive effect.
Vegetarian diets are also rich in potassium and magnesium, two minerals that hinder the action of excess sodium to the benefit of blood pressure. However, it must be specified that vegetarian diets only exert a preventive role in hypertension when they allow to maintain normal weight and do not abundantly use aged cheese, preserved foods and added salt.
The scientific data are difficult to interpret.
The consumption of fruit and vegetables seems to be associated with the reduction of the risk of onset of vascular diseases.
This is because, for various reasons, vegetarian diets improve metabolic diseases and decrease the process of atherosclerosis.
In addition, they may have a positive effect on blood fluidity and decrease the risk of platelet aggregation; this prevents the agglomeration of clots potentially responsible for embolism and stroke.
The vegetarian regime statistically decreases mortality from this disease.
However, some believe that vegetarian diets may be responsible for hyperhomocysteinemia (because of vitamin B12 deficiency), a very important risk factor for vascular disease.
The bibliographic data concerning the correlation between diet and cancer are not entirely clear and sometimes even conflicting.
For example, many believe that the consumption of proteins of animal origin may favour the appearance of certain cancers. Here, vegetarian diets would play a preventive role.
The scientific evidence is not clear or well defined.
Instead, it has been shown that the richness of fibre and plant antioxidants (vitamins, polyphenols, etc.) can have a preventive effect against digestive tract neoplasms.
What are the negative aspects of vegetarian diets?
The classic problems of the vegetarian diet concern the presumed deficiency of iron, vitamin B12, vitamin D, protein and calcium (only if milk and its derivatives are eliminated from the diet). If it is possible to satisfy the needs of these nutrients by avoiding the use of animal products, some very important aspects must be taken into account:
- Not all people have deep knowledge in the food and dietary field; in the absence of such bases, it is very easy to fall into error, in fact it is enough to deviate even a little from the proposed dietary models to reduce the intake of nutrients below the recommended values.
- The very supporters of vegetarianism after stating that the vegan diet is healthy and complete, they suggest the use of supplements or fortified foods to avoid specific vitamin or mineral deficiencies.
- Especially for a sportsman, a pregnant woman, a nurse, a small child and an elderly person, the vegan diet is difficult to “balance” and it is normal that it requires supplementation; it would be mature for the vegan community to admit that they are potentially subject to certain nutritional deficiencies. It is a reasonable price to pay to defend one’s principles and ideologies;
- Vegetables, as we have seen, are fundamental for our health, but like all things it is good not to overdo it with their consumption. Exaggerating with fruit, vegetables, cereals, pseudo-cereals and legumes can be counterproductive. Too many vegetables bring an excess of fibre, oxalates and phytic acid, substances that hinder the nutritional absorption and especially that of some minerals – including calcium, iron and zinc – of which some vegetarian diets are already tending to be poor;
- We should also remember it that the external part of the seeds, which is normally removed during refining and instead preserved in whole food, has a higher exposure to chemicals used in agriculture. For this reason, it is good to find out the origin of wholemeal foods, to avoid the excessive introduction of substances harmful to our body. We now establish it that the body has systems of elimination of contaminants and that, respecting a varied diet, can perfectly cure itself. Increasing immeasurably the income of certain pollutants, it is not to be excluded that these can accumulate damaging to health;
- The iron present in vegetable foods is less absorbable than that typical of animal products. It is captured slowly and in lower quantities (only 5-10% of the ingested vegetable iron is actually absorbed). The capture of this mineral depends on the chemical form in which it is found; in fact, iron is better absorbed than non-emic iron. We can find Emic Iron in meat, fishery products, offal and eggs, while non-emic iron is mainly found in vegetables (mainly legumes and cereals). More than 20% of EME iron introduced with the diet is absorbed at intestinal level, while non-EME iron is captured at less than 5%. The absorption of iron:
- Increases in the presence of vitamin C (point in favour of vegetarian diet)
- Decreases if associated with the anti-nutritional factors already mentioned in point 3
- Decreases if associated with significant calcium and phosphorus content
- It increases as the gastric pH decreases (a point in favour of the traditional omnivorous diet, which requires a certain acidity in the stomach to digest the greater amount of protein in food of animal origin).
Some of the best vegetarian recipes are those used in the ketogenic diet.