**1. Introduction**

Despite the fact that vegetarianism has been known for several millennia, this diet still has many of its adherents as well as despisers. We have been dealing with the issue of health effects of plant foods since 2000 in partial epidemiological studies, so we decided to summarize our findings on how vegetarianism affects the population of Slovakia.

Plants are the basic components of the food chain, in which they provide all the essential mineral and organic nutrients for humans either directly or through animal production. A comprehensive, varied diet ensures nutritional quality (intake of all nutrients) and, despite the concentrations of nutrients in the consumed food mixture corresponding to the recommended nutritional doses, also the nutritional quantity. Both of these criteria for optimal diet are essential for the development and maintenance of human health [1]. Vitamin B12, vitamin D and n-3 fatty acids are lacking in plant food sources. In particular, the content of methionine and lysine (also other essential amino acids), iodine and carnitine is significantly reduced compared to animal food [2, 3]. The absorption of iron, calcium, zinc, copper, manganese and selenium can be inhibited by plant food components [4, 5]. These facts may be associated with many health risks in the population with exclusive or dominant consumption of plant foods [6, 7].

To prevent these risks, it is necessary to consume food or pharmaceutical supplements to compensate for deficient nutrients.

Saturated fats (animal source) cause hypercholesterolemia, polyunsaturated fats (vegetable oils) can lower blood cholesterol levels. Monounsaturated fatty acids (oleic acid - olive oil, rapeseed oil, sesame oil, hazelnuts, almonds) also have a hypolipidemic effect and, in addition, have a saving (non-reducing) effect on HDL-cholesterol [8]. Compared to nonvegetarians, vegetarians in the Oxford vegetarian study had a 24% reduction in mortality from ischemic heart disease (DRR/death rate ratio/ = 0.76) [9]. When the meat-consuming group was divided into regular consumers of red meat (at least once a week) and semi-vegetarians (consumption of fish and white meat less than once a week), the DRR for semivegetarians was 0.78 and for vegetarians 0.66. Consumption of cheese, eggs, total fat, and cholesterol has been associated with mortality from ischemic heart disease [10]. Compared to subjects who ate relatively few of the commodities and nutrients listed, the DRR in those with the highest consumption of cheese was 2.47, eggs 2.68, animal fat 3.29, and cholesterol 3.53. Analysis of 5 prospective studies also expressed mortality from cerebrovascular disease - DRR in vegetarians 0.93 [11]. The results of a study of more than 34,000 Adventists on Day 7 in California showed a significant association between beef consumption and fatal coronary heart disease. In men eating beef more than 3 times a week, the relative risk (RR) was 2.31 compared to vegetarians. Furthermore, this study found a significant protective association between nut consumption and fatal and non-fatal ischemic heart disease for both sexes (RR = 0.5 for subjects consuming nuts more than 5 times per week compared to less than 1 time/week) and a reduced risk of ischemic heart disease in subjects who prefer wholemeal bread versus white [12].

Fiber consumption can also reduce the risk of cardiovascular disease [13]. An analysis of 10 prospective studies in the US and Europe of more than 336,000 subjects showed that an increase in fiber consumption every 10 g/day was associated with a 14% reduction (RR = 0.86) in all coronary cases and a 27% reduction (RR = 0.73) in risk coronary death [14]. Other plant food components (saponins in legumes, plant proteins, antioxidant nutrients - vitamin C, vitamin E, β-carotene, selenium, polyphenols and flavonoids) are added to the beneficial effect of fiber [15]. By evaluating current knowledge about the protective effects of plant food ingredients, scientists agree on the need to consume a variety of plant foods [7]. Vegetarian studies have confirmed that subjects with low or no consumption of animal fats and with a dominant consumption of plant foods have low values of atherosclerosis risk factors and higher values of parameters with antisclerotic properties compared to the general population [14].

Cardiovascular disease can be positively influenced by the consumption of plant proteins. Vegetable proteins versus hen egg reference protein or other animal proteins have a reduced content of some essential amino acids and an increased content of some non-essential amino acids [15]. Experimental studies have shown that cholesterol-free diets containing milk protein, casein or other animal proteins, induced an increase in plasma concentrations of total and LDL-cholesterol, while plant proteins did not have such an adverse effect [16]. By selectively increasing amino acid intake, hypercholesterolemia was found to be primarily due to essential amino acids. Higher intake of lysine and methionine (from animal proteins) adversely affects the metabolism of phospholipids in the liver. Higher amounts of methyl groups from methionine may lead to increased secretion of apoB lipoproteins. These data suggest that lower methionine and lysine intake in subjects with exclusive or predominant consumption of plant proteins represents a protective effect against cardiovascular risk. In the general population, the ratio of animal to vegetable protein consumption is about 60:40, more preferably 50:50.

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**Table 1.**

obesity.

*Health Effects of Plant Foods and the Possibility of Reducing Health Risk*

diabetes, kidney disease, digestive tract and thyroid disease.

dietary, biochemical and microbiological examination.

weight. The body mass index (BMI = weight/height<sup>2</sup>

**2.1 Somatometric examination**

percentage of fat in vegetarians.

*Characteristics of the monitored group.*

**2. Characteristics of the monitored group of probands with different** 

Our research included a randomly selected adult population from Bratislava and its surroundings. A database of volunteer addresses from previous solved research projects monitoring the health and nutritional status of the population was used. The number of probands in both research groups (non-vegetarian group/general population /and alternative diet group with predominance of plant food consumption/vegetarians)) as well as other characteristics of the groups are given in **Table 1**. Examinations were performed in the spring. The intake of vitamins, minerals and trace substances was only in its natural form (no supplementation). Another limitation of random selection was the requirement that probands be subjectively healthy, i. zn. without cardiovascular disease, cancer,

Monitoring of health and nutritional status was performed by somatometric,

Somatometric examination was performed by measuring body height and

overweight and obesity. A calipometer, Omron and InBody 230 were used for further somatometric measurements the type of obesity was determined after recalculation. We used Omron to measure bioimpedance in the upper half of the body, but the results can be influenced by the type of obesity and data entry. InBody 230 was performed by bioimpedance measurement using DSM-BIA (segment multi-frequency bioelectric impedance) technology, ie measurement of the upper and lower body, so the results are not affected by the type of

At first glance, most vegetarians are recognizable. They have a slim figure, pale skin and are anemic. These facts were also confirmed in our study (**Table 2**). Subcutaneous fat on the abdominal algae measured with a caliper, as well as visceral fat, have been significantly reduced by vegetarians compared to non-vegetarians. Also, the percentage of fat measured using the InBody 230 and Omron BF-306, both instruments using the bioimpedance method, confirmed a significantly reduced

n 920 958 age range (y) 20–60 20–60 average age (y) 40,41 ± 0,96 40,50 ± 1,13 BMI (kg/m2) 21,46 ± 0,35\*\*\* 25,60 ± 0,47

smokers 0 0 Systolic blood pressure (mmHg) 120,57 ± 1,44\*\*\* 143,59 ± 1,70 Diastolic blood pressure (mmHg) 72,46 ± 0,95\*\*\* 88,27 ± 0,94 Pulse rate (1 minute) 70,57 ± 1,33 77,01 ± 1,25

time vegetarianism (y) 18,61 ± 0,63

) was calculated to assess

**Vegetarians Non-vegetarians**

*DOI: http://dx.doi.org/10.5772/intechopen.94096*

**eating habits**
