Metabolic risk factors, blood pressure and atherogenic indices of cardiovascular disease across different quartiles of dietary sodium to potassium ratio among young semi-professional athletes with overweight or obesity

Abstract

Background

Previous studies have revealed the role of the dietary sodium-to-potassium ratio in predicting cardiovascular and total mortality. However, a limited number of studies have investigated the association between the dietary sodium-to-potassium ratio and individual biomarkers of metabolic disease in athletes. In this study, we aimed to compare metabolic, atherogenic, and anthropometric risk factors for cardiovascular disease across different quartiles of the dietary sodium-to-potassium ratio among young semi-professional athletes with overweight or obesity.

Methods

In this cross-sectional study, 637 young semi-professional athletes, aged 20–40 years, were selected from active athletic and fitness clubs. Anthropometric measurements were performed, and fasting blood sugar, serum lipids, and lipoprotein (a) [Lp(a)] were measured. Atherogenic indices, including the atherogenic index of plasma (AIP), Castelli risk index (CRI)-I, CRI-II, and lipid tetrad index (LTI), were calculated.

Results

Participants in the highest quartile of the dietary sodium-to-potassium ratio were younger and had a higher waist-to-hip ratio (WHR) compared to those in the lowest quartile. Additionally, those in the highest quartile showed significantly higher serum total cholesterol and Lp(a) concentrations after adjusting for confounding factors (P < 0.05).

Conclusion

Our findings suggest that individuals in the higher quartiles of the dietary sodium-to-potassium ratio exhibit less favorable serum lipid profiles. Further longitudinal and interventional studies are needed to clarify the potential therapeutic role of reducing the dietary sodium-to-potassium ratio in managing cardiovascular disease risk factors.

Introduction

Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide, responsible for an estimated 17.9 million deaths annually, according to a WHO report [1]. Key risk factors for CVDs include high blood pressure, an unhealthy diet, elevated cholesterol levels, and obesity [2]. The World Heart Federation reported that the leading modifiable risk factor for CVD-related deaths in 2021 was high blood pressure, accounting for 10.8 million deaths globally. This was followed by elevated LDL cholesterol, high fasting blood glucose, and high body mass index, which contributed to over 3.8 million, 2.3 million, and 2 million deaths worldwide, respectively [2]. Behavioral factors, such as a sedentary lifestyle, unhealthy dietary habits, and tobacco and alcohol consumption, are among the major contributors to elevated blood pressure, obesity, and dyslipidemia [3].

Recent epidemiological studies have shown that athletes, despite their high levels of physical activity, are not immune to cardiovascular disease (CVD). Several factors contribute to the development of CVD in athletes, including genetic predisposition, unhealthy dietary habits, the use of supplements, and excessive exercise-induced stress on the cardiovascular system [4]. "A career in sports does not eliminate the risk of cardiovascular disease," as demonstrated by a recent systematic review and meta-analysis [5].

The Oxford Dictionary defines an athlete as a person who competes in one or more sports requiring physical strength, speed, power, or endurance [6], Semi-professional athletes, on the other hand, are individuals who participate in sports at a competitive level while balancing other professional commitments. These athletes typically receive some financial compensation for their sports involvement but do not rely on it as their primary source of income. Semi-professional athletes are characterized by their dual commitment to both athletics and professional careers, with diverse sports backgrounds such as soccer, cycling, and mountain biking. They are also highly engaged in training, measured in metabolic equivalents (MET-min/week), which vary according to the specific sport and training regimen [7,8,9].

Numerous studies have highlighted the importance of proper nutritional status for the physical performance and post-exercise recovery of semi-professional athletes [10,11,12]. However, the dietary intake of semi-professional athletes often falls short of sports nutrition recommendations [10, 11]. These athletes are also characterized by elevated levels of oxidative molecules, free radicals, and upregulation of antioxidant systems [13]. The increase in free radicals can reduce muscle force by inhibiting the sodium–potassium ATPase pump [14], suppressing sarcoplasmic reticulum calcium-ATPase activity [15], and decreasing myofibrillar calcium sensitivity [15]. Dietary sodium and potassium play crucial roles in regulating fluid balance and neuromuscular function, directly impacting athletic performance [16]. Maintaining an optimal sodium-to-potassium ratio can improve endurance, strength, and exercise capacity, allowing athletes to perform at their peak [17]. An appropriate sodium-to-potassium ratio, which enhances dietary acid load, is essential for preventing dehydration, heat-related illnesses, and maintaining cardiovascular health, especially in blood pressure regulation and the prevention of cardiovascular disease. While high sodium intake is linked to hypertension, endothelial dysfunction, and an increased risk of cardiovascular events, adequate potassium intake has antihypertensive effects, promoting vasodilation, sodium excretion, and arterial compliance [18, 19].

Previous studies have primarily focused on the role of dietary sodium and potassium in controlling hypertension and reducing the risk of cardiovascular disease (CVD). Numerous observational and interventional studies have demonstrated the negative impact of high dietary sodium intake on blood pressure and CVD [20,21,22,23]. In contrast, potassium intake has been shown to have beneficial effects on both blood pressure and hypertension management [22, 24].

The dietary sodium-to-potassium ratio is considered more important than the individual intake of these two elements. The ideal ratio is approximately 1:3, meaning potassium intake should ideally be around three times that of sodium. The World Health Organization (WHO) recommends a daily intake of less than 2000 mg of sodium and more than 3510 mg of potassium, with a sodium-to-potassium ratio of less than 1.0 being optimal for cardiovascular health [25]. However, due to low compliance with dietary guidelines and recent findings suggesting that a sodium-to-potassium ratio between 1.0 and 2.0 can also reduce the risk of cardiovascular disease, a ratio of less than 2.0 has been proposed as a more attainable suboptimal goal [26, 27].

Recent studies have examined the relationship between dietary sodium and potassium balance and cardiovascular disease (CVD) [28,29,30], highlighting the impact of the dietary sodium-to-potassium ratio on blood pressure and hypertension [29]. A 24-year follow-up study conducted in Japan found that the dietary sodium-to-potassium ratio was an independent and significant risk factor for all-cause mortality, as well as mortality from stroke and CVD, among 8283 men and women aged 30–79 years who had no prior history of hypertensive treatment, stroke, or acute myocardial infarction [30]. Another longitudinal study involving 2050 men and women aged 30–84 years, who were free of CVD at baseline, showed that a higher dietary sodium-to-potassium ratio was associated with an increased risk of CVD after a median follow-up of 10.6 years [hazard ratio (HR) = 1.99, 95% CI = 1.13–3.52] [31]. Conversely, some studies have reported no association between the dietary sodium-to-potassium ratio and all-cause or CVD mortality [23, 32] while others have found a positive association between the urinary sodium-to-potassium ratio and all-cause or CVD mortality [23].

Most studies on the health effects of the dietary sodium-to-potassium ratio have primarily focused on its association with blood pressure and have evaluated outcomes such as all-cause mortality, cardiovascular disease (CVD), and stroke. Few studies have examined the role of the sodium-to-potassium ratio in isolated metabolic risk factors, such as serum lipids, glycemic markers, or atherogenic indices. For example, a retrospective cross-sectional study using pooled data from the National Health and Nutrition Examination Survey (NHANES) found that a higher dietary sodium-to-potassium ratio was associated with increased odds of elevated HbA1c concentrations in men (OR: 1.56, 95% CI: 1.24–1.96). Additionally, higher odds of low HDL-cholesterol were observed in the highest quintiles of the dietary sodium-to-potassium ratio for both men (P for trend = 0.002) and women (P for trend < 0.001). However, no significant associations were found between the dietary sodium-to-potassium ratio and hypercholesterolemia in men, or high non-HDL-cholesterol levels in either gender [28].

Another study conducted in Korea [33], found that individuals in the highest quartile of the dietary sodium-to-potassium ratio had a 19% higher odds of having metabolic syndrome compared to those in the lowest quartile (P for trend = 0.001). This study also reported a significant increase in the risk of elevated blood pressure and elevated blood sugar associated with a higher dietary sodium-to-potassium ratio (P for trend = 0.015 and 0.012, respectively). Similarly, a study in China found a positive association between the dietary sodium-to-potassium ratio and both high blood pressure and hypertriacylglycerolemia [34].

Obesity is an independent risk factor for cardiovascular disease, with established roles in increasing blood pressure, inducing dyslipidemia, and promoting atherogenesis [35, 36]. In a study by Geleijnse JM et al. [23], the urinary sodium-to-potassium ratio was associated with an increased risk of hypertension specifically in overweight individuals who were initially free of CVD (RR = 1.19, 95% CI: 1.02–1.39). Additionally, other studies have reported a positive association between the urinary sodium-to-potassium ratio and obesity [37, 38].

Increased dietary sodium intake is also associated with a higher risk of both central and general obesity; the prevalence of obesity among athletes appears to mirror that of the general population. One study found that adult athletes in the United States were at least 3.1 times more likely to be overweight or obese compared to their non-US counterparts [39]. Additionally, obesity rates in China have surged in recent decades, with more than half of the country’s 1.4 billion population being overweight [40]. Projections suggest that by 2030, nearly 70% of the Chinese population could be overweight [41].

Due to the limited number of studies examining the role of the dietary sodium-to-potassium ratio in metabolic risk factors for cardiovascular disease, and the lack of research in the field of sports nutrition, this cross-sectional study aims to address this gap. For the first time, we compare metabolic risk factors—including serum lipids, glycemic markers, blood pressure, and atherogenic indices—across different quartiles of the dietary sodium-to-potassium ratio among young semi-professional athletes with overweight or obesity. The identification of semi-professional athletes in this study involved input from team managers, head coaches, and medical professionals.

Methods and materials

Study design, setting and participants

In this study, 637 young semi-professional athletes aged 20–40 years were selected from active athletic and fitness clubs in Xi’an, the capital of Shaanxi Province in Northwest China. The clubs were chosen through cluster random sampling from 11 districts in Xi’an, based on differences in socio-demographic levels. Within each district, athletic and fitness clubs were selected using simple random sampling. Participants were then enrolled through a convenience sampling procedure from these clubs. The inclusion criteria for participants were: aged 20–40 years, residing in Xi’an, having a healthy appearance, being overweight or obese (BMI 25.9 – 39.9 kg/m²), and consenting to participate in the study (Table 1, Fig. 1). Athletes were included if they had engaged in consistent exercise for at least 3 years, training at least 3 days per week for a minimum of 90 min per session [42]. Individuals were excluded if they had a history of cardiovascular diseases, diabetes, cancer, liver or kidney problems, or if they used any medications affecting electrolyte homeostasis and body metabolism. Additionally, those using supplements that could alter weight or electrolyte levels were also excluded from the study.

Table 1 Frequency distribution of study participants by sport type

Fig. 1

Study flowchart

Assessment of variables

Participants' general demographic information was collected using a questionnaire that included details about age, sex, personal and family medical history, and medication use. Physical activity was assessed using simplified Chinese-character version of the international physical activity questionnaire-long form (IPAQ) [43]. Height and weight were measured with a wall-mounted stadiometer and a Seca scale (Seca Co., Hamburg, Germany), with precision to the nearest 0.5 cm and 0.1 kg, respectively. Body mass index (BMI) was calculated as weight (kg) divided by height (m²). Waist circumference was measured to the nearest 0.1 cm at the midpoint between the lowest point of the ribs and the iliac crest. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using a calibrated mercury sphygmomanometer (Omron, Japan) on the same arm, following a minimum of 15 min of rest. The average of two readings was recorded. Biochemical variables, including serum lipids (e.g., triglycerides (TG), total cholesterol (TC), and high-density lipoprotein cholesterol (HDL-C)), fasting serum glucose, and serum lipoprotein (Lp) a, were measured after an overnight fast of 12 h. Serum samples were analyzed using an auto-analyzer (Alpha Classic E analyzer), and LDL-C was calculated using Friedewald's formula [44]. Dietary intake was assessed using a validated food frequency questionnaire (FFQ) for the Chinese population [45]. Participants provided information on the frequency and quantity of each food item consumed, which was used to evaluate their annual food intake. Food amounts were converted to grams using the Chinese Food Image Database and Sheppard’s basic recommendations for portion sizes, cooking yields, and edible quantities [46]. The NUTRITIONIST IV software (N Squared Computing, California, USA) was used to analyze daily dietary consumption, including calories, macronutrients, micronutrients, and the mean intake of sodium (Na) and potassium (K) over the past year. The sodium-to-potassium ratio was then calculated.

In the current study, atherogenic indices of plasma were calculated as follows:

• Atherogenic Index of Plasma (AIP): Log (serum triglycerides divided by serum HDL cholesterol)

• Catelli Risk Index (CRI)-I: Serum total cholesterol divided by serum HDL cholesterol

• Catelli Risk Index (CRI)-II: Serum LDL cholesterol divided by serum HDL cholesterol

• Lipid Tetrad Index (LTI): Serum cholesterol × triglycerides × lipoprotein (Lp) (a) divided by serum HDL cholesterol [47, 48].

Sample size and grouping variable

Sample size calculation for the current study was performed using the formula $n=\frac{\left(\mathrm{Za}/2\right)^2\mathrm p\left(1-\mathrm p\right)}{\mathrm d^2}$, where the prevalence of cardiovascular events with a higher dietary sodium-to-potassium ratio was estimated at 0.16 [49] with an error coefficient of d = 0.04 and a significance level of α = 0.05. This calculation resulted in an approximate sample size of 579. Considering a 10% dropout rate, the final estimated sample size was 637 participants. The dietary sodium-to-potassium ratio among participants ranged from 0.25 to 3.88, and they were divided into four groups based on this ratio: low (< 0.78), medium (0.78–1.06), high (1.06–1.45), and very high (> 1.45).

Statistical analysis

Continuous and discrete variables are presented as mean ± SD or n (%), respectively. Data normality was assessed using the Kolmogorov–Smirnov test, and Levene's test was used to evaluate the equality of variances. Comparisons of continuous and discrete variables across quartiles of the dietary sodium-to-potassium ratio were conducted using one-way analysis of variance (ANOVA) with Tukey’s post-hoc tests and chi-square tests, respectively. For dietary data with non-normal distribution, between-quartile comparisons were performed using the Kruskal–Wallis test. Trend analysis was conducted with polynomial linear contrast analysis. Adjustments for confounders were made using the General Linear Model (GLM) approach. Polynomial logistic regression analysis was performed in three models: Model I (crude), Model II (adjusted for age and sex), and Model III (adjusted for age, sex, BMI, physical activity, and energy intake) to evaluate the linear trend association between the dietary sodium-to-potassium ratio and biochemical outcomes. Partial correlation analysis was used to assess the linear association between dietary sodium and potassium intake and serum lipoprotein (Lp)(a). P-values less than 0.05 were considered significant. Data analysis was conducted using SPSS software (version 23; IBM Corp., Armonk, NY, USA).

Results

Individuals with a higher dietary sodium-to-potassium ratio were younger and had a higher waist-to-hip ratio (WHR) compared to those with a lower sodium-to-potassium ratio (Table 2; P < 0.05). No significant differences were observed in other demographic or anthropometric variables across the quartiles of dietary sodium-to-potassium ratio. Crude and energy-adjusted differences in dietary intake of various food groups are presented in Table 3. As indicated, significantly higher intakes of grains, organ meats, red meat, eggs, cholesterol, total fiber, and table salt were found in the higher quartiles compared to the lower quartiles of the sodium-to-potassium ratio (P < 0.05). Conversely, lower intakes of fish, low- and high-fat dairy products, fruits, vegetables, nuts, poultry, and sweets were noted in the highest versus lowest quartiles of the sodium-to-potassium ratio in both crude and energy-adjusted models (P < 0.05). Among beverages, those in the highest quartile had a higher intake of soft drinks and a lower intake of both low- and high-fat milk (P < 0.001). Table 4 presents a comparison of fasting blood sugar (FBS), metabolic, and atherogenic risk factors across quartiles of the dietary sodium-to-potassium ratio. Individuals in the second and third quartiles had significantly higher serum total cholesterol and Lp (a) concentrations compared to those in the other quartiles in both crude and adjusted models (adjusted for age, sex, BMI, energy intake, and physical activity; P < 0.05). Serum triglycerides (TG), the atherogenic index of plasma (AIP), and diastolic blood pressure (DBP) were higher in the second and first quartiles, respectively, compared to the other quartiles in the crude model. Systolic blood pressure (SBP) was higher in the first quartile compared to others in both crude and adjusted models. A significant trend was observed for serum TG, SBP, DBP, Lp(a), and AIP (P for trend). Table 5 illustrates the linear trend between the dietary sodium-to-potassium ratio and biochemical variables. Polynomial logistic regression revealed a significant positive association between serum LDL in the second quartile and between coronary risk indices (CRI-I and CRI-II) in the fourth quartile and the sodium-to-potassium ratio across all three models. Partial correlation analysis, adjusted for age, sex, BMI, energy intake, and physical activity, showed a significant positive correlation between dietary sodium (r = 0.428, P < 0.001), potassium intake (r = 0.305, P < 0.001), and serum Lp(a) concentrations (Fig. 2).

Table 2 General demographic and anthropometric characteristics of study population across quartiles of dietary Na/K ratio

Table 3 Dietary intake of energy, macronutrients and energy-adjusted intake of food groups across quartiles of dietary Na/K ratio

Table 4 Metabolic and atherogenic risk factors of study participants across quartiles of dietary Na/K ratio

Table 5 The association between biochemical variables and dietary Na/K ratio using multinomial logistic regression model

Fig. 2

The correlation between dietary sodium and potassium intake with serum Lp (a) concentrations among study population [(Na and Lp (a) correlation: r = 0.428, P < 0.001 and for K and Lp (a) correlation: r = 0.305; P < 0.001 using partial correlation analysis after adjustment for age, sex, BMI, energy intake and physical activity level)

Discussion

In the current study, overweight or obese young semi-professional athletes in the second and third quartiles of the dietary sodium-to-potassium ratio had significantly higher serum total cholesterol and Lp(a) concentrations compared to those in the other quartiles in both crude and adjusted models (P < 0.05). Additionally, systolic blood pressure (SBP) was higher in the first quartile compared to the other quartiles in both crude and adjusted models.

In the current study, overweight or obese young semi-professional athletes in the second and third quartiles of the dietary sodium-to-potassium ratio had significantly higher serum total cholesterol and Lp(a) concentrations compared to those in the other quartiles in both crude and adjusted models (P < 0.05). Additionally, systolic blood pressure (SBP) was higher in the first quartile compared to the others in both crude and adjusted models.

Our participants with a higher dietary sodium-to-potassium ratio were younger and predominantly male. These findings align with previous studies. In the study by Okada E. et al. [28], an increase in dietary sodium-to-potassium ratio was associated with a reduction in age across higher quintiles for both men and women. Similarly, as in our study, Li X. et al. [34], found that the number of men was greater in the highest quartiles of the dietary sodium-to-potassium ratio. In the EPIC-Norfolk study of 24,963 participants (including 11,267 men and 13,696 women), men had significantly higher sodium and potassium intake, as well as a higher sodium-to-potassium ratio [50].

In our study, participants in the higher quartiles of dietary sodium-to-potassium ratio had significantly higher WHR, cholesterol, LDL, and Lp(a) levels compared to those in the lowest quartiles. Increased serum triglyceride levels were also observed in the crude model, but not in the adjusted model. Similar to our findings, previous studies have reported an increased risk of cardiometabolic factors, including higher waist circumference [33], hypertriglyceridemia [33, 34], increased obesity risk [30, 33, 51], elevated HbA1c [30, 33, 51], elevated HbA1c [28], and high blood pressure [33, 34] in individuals with higher dietary sodium-to-potassium ratios. However, some discrepancies exist. For example, several studies have found reduced cholesterol levels with increasing dietary sodium-to-potassium ratios [28, 30]. These differences may be due to variations in the demographic characteristics of the populations studied, the health status of participants, and differences in dietary assessment methods.

In our study, SBP decreased only in the higher quartiles of the dietary sodium-to-potassium ratio. The relationship between dietary sodium and potassium intake and blood pressure may be influenced by genetic, environmental factors, or both. Certain polymorphisms, such as those in the adiponectin gene [52], the sodium-bicarbonate co-transporter gene [53] and the renin–angiotensin–aldosterone system [54] along with other genetic variants [55] may contribute to salt sensitivity and potassium sensitivity of blood pressure, affecting susceptibility to salt sensitivity of blood pressure (SSBP).

Another reason for the reduced SBP in the highest quartiles of the dietary sodium-to-potassium ratio may be attributed to the higher intake of dietary fiber and grains in these quartiles. However, even after adjusting for dietary fiber, the difference in SBP across quartiles remained significant. The dietary sodium-to-potassium ratio in our study population ranged from 0.25 to 3.88, with most participants (89.3%) having a ratio below two, which falls within the optimal and suboptimal range recommended by the WHO [25]. Similar to our findings, a population-based study in northern China found no significant difference in SBP across quartiles of the dietary sodium-to-potassium ratio (P = 0.149). However, in southern China, participants in the second and third quartiles had higher SBP compared to the other quartiles (P = 0.002). The authors suggested that regional disparities in the association between dietary sodium-to-potassium ratio and blood pressure in China could be due to differences in dietary habits, cooking methods, social environments, and local foods between South and North China [51]; Our study was conducted in Xi’an, a city in north-central China, and our results align with those findings. Regional variations in the relationship between dietary sodium, potassium intake, and blood pressure are evident in other countries as well. The National Health and Nutrition Examination Survey (NHANES) III revealed higher sodium and lower potassium intake in the southern United States compared to other regions, where the prevalence of hypertension was also higher than in the northern United States [56]. In our study, we reported dietary intake of food groups and ingredients across quartiles of the dietary sodium-to-potassium ratio. Significantly higher intakes of grains, organ meat, red meat, eggs, cholesterol, total fiber, and table salt were observed in the higher quartiles compared to the lower quartiles in both crude and energy-adjusted models (P < 0.05). Conversely, lower intakes of fish, low- and high-fat dairy products, fruits, vegetables, nuts, poultry, and sweets were noted in the highest versus lowest quartiles of the sodium-to-potassium ratio (P < 0.05). To our knowledge, only the study by Okada E. et al. has compared dietary intake of food groups across quintiles of the dietary sodium-to-potassium ratio. Similar to our findings, their study in Japan reported higher intakes of meat, eggs, and cereals, but lower intakes of fruits, vegetables, milk, and nuts in the higher versus lower quintiles of the dietary sodium-to-potassium ratio [28].

Lp(a), a novel marker of cardiovascular disease, is a low-density lipoprotein (LDL)-like particle bound to apolipoprotein (a). It plays a role in vessel calcification, vascular inflammation, and thrombosis [57]. Numerous epidemiological and genetic studies suggest a causal link between elevated Lp(a) concentrations and coronary artery disease [57,58,59], aortic valve stenosis [60]. Its harmful effects are likely due to its similarity to LDL and its structural resemblance to apolipoprotein (a) with plasminogen, which impairs thrombolysis [61].

Very few interventional studies have investigated the impact of therapeutic diets that reduce sodium intake on Lp(a) levels [62, 63]. In the current study, a higher dietary sodium-to-potassium ratio was associated with greater concentrations of Lp(a), independent of confounders. Additionally, there was a positive association between dietary sodium and potassium intake and serum Lp(a) levels, suggesting a potential therapeutic role for dietary salt restriction in managing Lp(a) concentrations. However, further research is needed to confirm these findings. According to our results, a higher dietary sodium-to-potassium ratio was associated with an increase in Lipid Turnover Index (LTI) at a near-significant level. LTI, a novel index of cardiovascular disease, reflects a mix of atherogenic and non-atherogenic lipid particles and is proposed as a model for global cardiovascular risk assessment [48].

In the current study, we used a semi-quantitative FFQ with an acceptable validity and reliability in China [45] with 109 food items. Previous questionnaires that was validated for athletes, included athletes of track and field, ice hockey, weightlifting, bicycle racing, judo, swimming, skiing, skating, table tennis, volleyball, basketball, baseball, lacrosse, and wrestling and had only 62 basic food items [64]. Similarly, another FFQ that was validated for Brazilian athletes contained 59 foods as predictors of the variance in nutrient intake [65]. These questionnaires included relatively limited number of food items and are not suitable for a comprehensive study. Our study population consisted from various sport fields and there is no validated FFQ to cover all of these sports in China. We must use a consistent tool for all of our participants to avoid any potential bias due to difference in food items.

Also, most large-sized athletes, including the present study participants, are categorized as unhealthy overweight or obesity based on their BMI [66]. Some of the athletes are completely metabolically healthy with daily dietary care or exercise habituation, in our study, the participants’ biochemical variables including serum lipids, blood pressure were optimal or near optimal range due to exercise effect. On the other hand most of same-sized sedentary have several healthy problems in general. Of course, some large-sized athletes have the risk of lifestyle diseases belong to their dietary life. Therefore, for the future studies comparing dietary sodium to potassium ratio and other variables between semi-professional athletes and sedentary individuals are suggested to better elucidate the effect of exercise on metabolic profile in obesity conditions.

In conclusion, our study reveals that a higher dietary sodium-to-potassium ratio is associated with increased central obesity, serum total cholesterol, and Lp (a) levels among young semi-professional athletes with overweight or obesity. Dietary interventions aimed at reducing the dietary sodium-to-potassium ratio are suggested as potential therapeutic strategies for reducing cardiovascular disease risk in this population.

The relatively large sample size and consideration of major traditional cardiovascular disease (CVD) confounders are strengths of the current study. Additionally, we accounted for table salt intake, a significant source of dietary sodium often overlooked in previous research [67]. However, the study has some limitations. We did not measure the urinary sodium-to-potassium ratio, which is a more precise indicator of dietary sodium and potassium intake. Nonetheless, previous studies have demonstrated a strong correlation between dietary sodium and potassium with urinary sodium and potassium concentrations [30, 68,69,70,71]; Furthermore, one study found that dietary sodium and potassium intake, rather than their urinary concentrations, are associated with cardiovascular events and all-cause mortality [23]. Additionally, the self-reported nature of our questionnaires may introduce potential biases in estimating food and nutrient intakes. Also, we did not ask the participants to report their training frequency or duration per a week. So, we did not have the quantitative data related data.