This study aims to evaluate the relationship between meat and processed meat consumption frequencies and lipid profile in a group of randomly selected patients with cardiovascular diseases. We assume that a high-frequency consumption of meat and especially processed meat will be associated with higher levels of total cholesterol (T-C), LDL cholesterol (LDL-C), and triglycerides (TG).

Data were expressed in figures as mean ± standard deviation (SD) and statistical comparisons between groups were made utilizing one-way analysis of variance (one-way ANOVA) followed by Tukey's post hoc test. Significance was accepted when p <0.05. The program STATISTICA Cz version 10 (TIBCO Software Inc., Palo Alto, California, USA) belonging to the available statistical programs and MS Excel 2007 (Microsoft Corporation, Redmond, Washington, USA) was used.

A well-balanced diet is an important element for health and wellbeing through the whole life span (Gille, 2010; Löser, 2014). It is still widely acknowledged that lean red meat is an important complete protein source, in addition to contributing to essential micronutrient requirements, particularly iron, zinc, and B vitamins (Biesalski, 2005; McAfee et al., 2010; Webster-Gandy et al., 2012; Pereira and Vicente, 2013).

Most participants consumed meat regularly. Only 1 man indicated they were vegetarian. Figure 1 shows the consumption frequency of different kinds of meat as stated by the participants of the study. Table 3 shows the effect of the frequency of consumption of meat on the lipid profile. Pork and poultry were consumed most often: 70.7% (pork) and 63.9% (poultry) of the participants indicated that they consumed these meats 1 – 2 times per week.

Similarly, Schmid et al. (2017) found out that, the consumption frequency of beef, pork, and poultry of elderly Swiss population is the highest, with ≥50% of the participants consuming these types of meats at least once a week. Kopčeková et al. (2015) in 204 patients with cardiovascular diseases have recorded consumption of meat more than four times per week in 60.28% of men, while more than 30% of men eat meat daily. Respondents indicated poultry and pork as the most commonly consumed meat. Escriba-Perez et al. (2017) monitored the consumption of meat in 800 respondents aged 25 to 75 years. Most commonly consumed was chicken, which consumed up to 90.87% of respondents at least once a week. The second most frequently consumed was beef (63.62%), and the third was pork (52.62%).

High concentrations of total cholesterol, LDL cholesterol, and triacylglycerols indicate that the individual is at risk for the onset of cardiovascular disease (Wooton and Lynne, 2017). Elevated serum LDL-C is a long-established risk factor for the development of heart disease; however, the relationship between serum concentrations of LDL-C and dietary cholesterol is not clear (Zachary et al., 2017). Reducing high blood cholesterol is thus important for CVD prevention (Grundy et al., 1990; Cohen et al., 2006). LDL-C is a measure of the total cholesterol content of LDL particles, reflecting both the number of LDL particles and their cholesterol content. Most current guidelines include LDL-C as a primary target for initiating and adjusting lipid-lowering interventions (Stone et al., 2014; Jacobson et al., 2014).

Red meat intake is commonly considered a risk factor for CVD because of its saturated fat and cholesterol contents (Rohrmann and Linseisen, 2016).

Our results show, that most respondents consume meat 1 – 2 times per week, while we did not notice a significant effect (p >0.05) of the type of meat on the lipid profile.

The highest T-C, LDL-C, and TG values were seen in men who consume pork 3 – 4 times per week. Statistically, significant was the only effect of pork meat on total cholesterol and triglycerides (p <0.05). In the consumption of beef and poultry, there was a non-significant effect on biochemical parameters of blood (p >0.05). Kopčeková et al. (2015) in 204 patients with cardiovascular diseases found in both men and women in significantly higher values of HDL for the less frequent consumption, while the values of triglycerides and LDL cholesterol were higher for more frequent consumption. Kontogianni et al. (2008) found that a high intake of red meat (more than 8 servings/month) was associated with an increased risk of acute coronary syndrome, but low income (less than four servings/month) showed no association. A recent meta-analysis of 24 randomized controlled trials assessing the effects of red meat intake on CVD risk factors concluded that ≥0.5 serving/day of red meat did not influence blood lipids, lipoproteins, or blood pressure in comparison with <0.5 serving per day (O’Connor et al., 2017). According to Guasch-Ferré et al. (2019) findings from the present systematic review and meta-analysis showed that total red meat intake did not differentially influence blood lipids and apolipoproteins, except triglycerides, when all comparison diets were analyzed together.

Processed meat includes meat products that have been modified to change the taste or extend shelf life through curing, smoking, salting, or adding preservatives. Frequently consumed examples are: ham, sausages, salami, bacon, hot dogs, corned beef, beef jerky, ham, canned meat, and meat-based sauces (Rohrmann et al., 2013; Clonan, Roberts and Holdsworth, 2016). Accumulating evidence links excessive consumption of processed meat, and to a lesser extent unprocessed red meat, to an increased risk of obesity, diabetes, cardiovascular diseases, and some cancers (Micha and Mozaffarian, 2010; Zeng et al., 2019).

Figure 2 shows the consumption frequency of different kinds of processed meat as stated by the participants of the study. Table 4 shows the effect of the frequency of consumption of selected processed meat on the lipid profile.

Most respondents consume frankfurters (hot dogs) 3 – 4 times per week (35.5%) or 1 – 2 times per week (28.2%). Approximately 11% of respondents consume frankfurters daily, which is associated with non-significant higher LDL and lower HDL levels (p >0.05). We recorded a significant effect (p ˂0.05) of the consumption of frankfurters on the lipid profile. Almost half of the respondents consume meat pate 1 – 2 times per week and 24.8% only 1 – 2 times per month. Most respondents consume ham 3 – 4 times per week (42.5%), daily consumption of ham was recorded in 17.5% of patients. Different frequency of ham and meat pate consumption show non-significant changes for the lipid profile (p >0.05). Up to 40.2% of respondents consume salami 3 – 4 times/week, and we recorded a significant effect on LDL levels between consumption 1 – 2 times/week and sometimes (p ˂0.05). We also monitored the consumption of traditional Slovak brand products (sausage, headcheese, and others). Processed meats such as sausages have a higher content of saturated fatty acids and cholesterol than fresh red meat; reaching the proportion of fat in sausages more than 50% of weight (Lajous et al., 2014). Almost half of the respondents (48.9%) state that they do not consume sausage, headcheese, and others at all. 29.1% of patients consume this product 1 – 2 times per month and 22.0% 1 – 2 times per week. Respondents who consume sausage, headcheese, and other products 1 – 2 times a week have non-significant higher T-C, LDL, TG, and lower HDL compared to less frequent consumption.

Micha and Mozaffarian (2010) in their meta-analysis of 20 studies (17 prospective cohorts and 3 cases control studies) that included 1218380 individuals concluded that intake of processed, but not red, meat was associated with an increased incidence of coronary heart disease and the authors speculate that the higher sodium and nitrate content of processed meat might contribute to their impact on CVD. This investigation in EPIC, including nearly half a million participants across 10 European countries and more than 5000 cardiovascular events, confirms that consumption of processed meat is strongly associated with CVD risk, and that consumption of unprocessed red meat has little to no association (Rohrmann et al., 2013). Watson and Preedy (2013) report the results of research that focused on the effect of regular consumption of processed red meat (25, 75 grams or more per day) in 37035 healthy people. Probands who consumed 75 or more grams of meat products per day were 28% more likely to have heart failure than those who consumed less than 25 grams of meat products per day. Probands who consumed the most meat products had at least twice the risk of dying from CVD compared to those who consumed them.