INTRODUCTION
Data from the Department of Statistics and Health Ministry show that the main cause of death in Malaysia was ischemic heart disease, reaching 13.2% in 2016 and increasing to 13.9% in 2017 (Mahidin, 2018). Malaysia is ranked sixth in the Asia Pacific region and the top country within Southeast Asia for both obesity and diabetes (Malaysia-Nutritional and Food Supplements, 2019). It is a serious non-communicable disease (NCD) that may contribute to cardiovascular disease and other chronic diseases. Nowadays, dietary supplements are a choice for upper-middle and high-income families in Malaysia to take charge of their health as well as decrease the risk of NCD (Malaysia-Nutritional & Food Supplements, 2019). However, health indicators such as body mass index (BMI), blood pressure, blood glucose, lipid profile, liver function test, and health indicator parameters should be monitored to determine the effects after supplementation.
Masood and Miraftab (2010) stated that dietary complements derived from plants are becoming more popular in the industry. Scientists are continually trying to develop novel ways of alleviating ills and finding new treatments for chronic diseases. Therefore, the increasing use of herbal supplements by the Malaysian population has become a pressing issue in Malaysia (Malaysia-Nutritional & Food Supplements, 2019). The psyllium husk and selected herb mixture is a combination of dietary supplements that may bring a variety type of benefits to human. Psyllium husk is a dietary fiber used to help in weight reduction due to its satiety effect and promote natural bowel movement to prevent constipation (Hefny et al., 2018). Herbs are crude plant materials such as leaves, flowers, fruit, seed, stems, wood, bark, roots, rhizomes, or other plant parts and can be used in natural product supplements (World Health Organization, 2000).
Globally, herb mixtures are a common dietary supplement product. According to World Health Organization (2019), approximately 68% of adults use dietary supplements in the United States. There was a 9.1% growth in the food supplement market in Asia and the Pacific, accounting for 31.2% of people in 2013 (AlTamimi, 2019). It is a lucrative industry, and consumers tend to buy such products for their health claims. The Malaysian Adults Nutrition Survey 2014 found that 28% and 34% of Malaysian adults reported consuming vitamin/ mineral supplements and food supplements, respectively (Mohd Zaki et al., 2018). Since there are no regulations for supplements in Malaysia, they are available in numerous places and sold without a prescription (Sedek et al., 2018). Maughan et al. (2004) reported that supplement users typically do not get medical advice. While supplements have the potential to be beneficial to health, they also have risks. Hence, the US Food and Drug Administration (FDA) (2017) has stated that it is important to have a safety and effectiveness authority for dietary supplement products before they are marketed.
In the present study, it is believed that psyllium husk and selected herb mixture have brought beneficial effects for female adults. The supplement consists of Garcinia cambogia, Quercus infectoria, Pueraria mirifica, Piper betle, Labisia pumila, astaxanthin, marine collagen, ginger, and honey. Singh (2015) stated that the astringent action of Q. infectoria can be used to treat uterine prolapse, leucorrhoea, and excessive uterine bleeding. A study by Suwanvesh et al. (2017) has shown that P. mirifica improved the signs of vaginal atrophy and restoring vaginal epithelium in postmenopausal women. Additionally, Salehi et al. (2019) stated that P. betle can be used to promote vaginal health, as well as reduce itching of the vagina. Furthermore, L. pumila is widely used by Malay women in Malaysia to ease childbirth as well as to treat postpartum illnesses (Ezumi et al., 2007; Choi et al., 2010). Therefore, this study aims to determine the effects of the psyllium husk and selected herbs mixture supplementation consisting of G. cambogia, Q. infectoria, P. mirifica, P. betle, L. pumila, astaxanthin, marine collagen, ginger, and honey on health indicators (BMI, blood pressure, blood glucose, liver function, lipid profile, and quality of life) among the female adults with cardiovascular disease risk factors, including high BMI and elevated lipid profiles (total cholesterol, LDL-cholesterol).
MATERIALS AND METHODS
Research design
A simple randomized controlled study was carried out in Universiti Malaysia Terengganu. Subjects were screened and recruited between August and September 2019. Charan and Biswas (2013) were used for sample size calculation for confidence level of 95% and precision was assumed to be 0.5. Subject inclusion criteria were female adults between 30 and 50 years old and BMI range with 21–32 kg/m2. The range of BMI was chosen based on the mid-point for normal BMI range and the mid-point for obese class I. The age range was taken based on the mid-career age of females which generally can be started at 20 and last at 60 years old. A total of 76 adults were screened and 24 adults were recruited, as shown in Figure 1. Subjects were randomized using permuted block four randomizations with an allocation ratio of 1:1.
Research instrument
Body weight, height, blood pressure, blood glucose, and blood samples were taken twice before starting the intervention and after the 1-month intervention period. The body weight of subjects was measured using a weight balance (CAMRY, China). Height was determined using a portable stadiometer (SECA, Germany). Systolic and diastolic blood pressure in mmHg were measured using automatic blood pressure monitors (Omron, Japan). Fasting blood glucose in mmol/l was measured using glucometer (Accu-Chek, Indiana). A 5-7 ml blood sample was taken from the subjects after 8–12 hours’ fasting by medical personnel at the Universiti Malaysia Terengganu Health Centre. The blood was sent to an accredited lab to determine the results of the liver function test and lipid profile. A self-administered questionnaire was used in the present study. The three sections of the bilingual Malay and English questionnaire were used to obtain personal information, physical measurement, and health indicator parameters. Part A included personal information such as name, age, race, and origin state. Part B included physical measurements such as body weight, height, BMI, blood glucose, and blood pressure. Part C included health indicator parameters and physical and mental symptoms ranked from 1 to 5.
 | Figure 1. Sampling framework. [Click here to view] |
Statistical analysis
The data were analyzed using Statistical Package for Social Science version 23.0. The statistical analysis was performed by using the independent t-test and paired t-test (normal distribution) or Mann-Whitney U test and Wilcoxon’s signed-rank test (nonnormally distribution). A 95% confidence interval was used in all analyses to indicate significant outcomes. The normality test was tested by the Shapiro-Wilk test, since the sample size was smaller than 50 (Shapiro and Wilk, 1965).
RESULTS
Baseline characteristics
A total of 24 female subjects were recruited and randomly allocated into two groups, with 12 subjects in the control group and 12 subjects in the supplement group. Subjects recruited in this study were not diagnosed with any diseases and did not take any medication or supplementation. The median BMI was 27.7 and 27.3 for the control and supplementation groups, respectively, which were considered overweight. There were no significant differences in all the baseline parameters between the supplement group and control group although the subjects were randomly assigned into two groups (Table 1). Overall, the compliance was 100% and thus all subjects were included in the final analysis.
Anthropometric measurement
The present study found that there was a significant difference (p < 0.050) in BMI between baseline and after a 1-month intervention period in both groups as shown in Table 2. However, there was a significant increase (p = 0.002) in the BMI in the control group and a significant decrease (p = 0.002) in the BMI in the supplement group after the 1-month intervention period, respectively, as compared between the two groups (Table 3).
Blood pressure and blood glucose
The present study found no significant changes (p > 0.05) in systolic blood pressure (SBP) and diastolic blood pressure (DBP) in both groups at the end of the study (Tables 2 and 3).
It was found that there were no significant differences (p > 0.05) in fasting blood glucose (FPG) in both groups after the 1-month intervention period, as shown in Tables 2 and 3.
Liver function test and lipid profile
There were no significant differences (p > 0.05) in all the indicators in the liver function tests in both groups (Table 2). There was a significant increase in the absolute change of the AST (p = 0.039) and ALT (p = 0.041) in the supplement group (Table 3).
There were no significant differences (p > 0.05) in lipid profile in the supplement group, apart from high-density lipoprotein cholesterol (HDL-c) and TC/HDL-c ratio (p < 0.05) (Table 2). On the other hand, there were no significant differences (p > 0.05) in lipid profile in the control group, except for TC and HDL-c, as shown in Table 2. In addition, there was a significant decrease in absolute change (p = 0.033) and percentage change (p = 0.039) in TC/HDL-c ratio as compared between groups (Table 3).
Health indicator parameter
The present study found no significant changes to any health indicator parameters in both groups after the 1-month intervention, as shown in Table 4.
DISCUSSION
This study found a significant difference in BMI whereby there was an increase in absolute change by 0.32 kg/m2 (+1.09%) in the control group and a decrease by 0.25 kg/m2 (−-1.04%) in the supplement group. A study by Cicero et al. (2007) also demonstrated that the psyllium powder decreased BMI significantly (−0.8 ± 0.2) in 96 hypertensive overweight individuals after 4 months of supplementation. If the present study data is extrapolated for 4 months, BMI decreases by ≈−0.8 kg/m2, similar to a previous study.
Although all respondents from the supplement group reported that the supplement gave them a satiety effect through an open-ended general comment section, a significant difference in the satiety score compared to the control group was not observed. This fiber-rich psyllium husk will slow down gastric emptying, decrease the speed of intestinal passage rates, and increase nutrient absorption in the small intestine (Wanders et al., 2011; Pal and Radavelli-Bagatini, 2012). Hence, the respondents might reduce their food intake portion size. Furthermore, all respondents from the supplement group also stated that their bowel movement improved after consuming the supplement based on open-ended general comments. Three respondents said that their stool excretion increased from once to twice daily as stated in the detailed information checklist and the other six respondents claimed that time spent for defecation was shortened. The improvement in the stool excretion process will increase the bile acid excretion and this will stimulate the liver to increase bile acid production instead of decreasing the fat absorption by body tissues (Romero et al., 2002).
Trippi (2017) reported that the hydroxycitric acid in G. cambogia will interrupt lipogenesis which prevents carbohydrates converted to fatty acids. Hence, it will reduce body fat accumulation and induced weight loss in human models (Kothadia et al., 2018). In summary, apart from the reduction of food intake portion size, an increase of the stool excretion as well as decrease of fat absorption in the body will induce to decrease in BMI.
The present study shows no effect of supplementation on SBP and DBP in both groups after a 1-month intervention period. Previous study reported no improvements in blood pressure in overweight and obese individuals after 12-week psyllium fiber supplementation with the dosage of 21 g/day (Pal et al., 2011b). The change in blood pressure may not be related to an increase in fibre, but the healthy diet intake may be a factor in affecting this parameter (Pal et al., 2011b).
As compared to four- and 6-month randomized psyllium fibre (10.5 g/day) supplementation study by Cicero et al. (2007), their results significantly reduced the SBP of 96 hypertensive overweight individuals by −3.1 ± 0.9 and −5.2 ± 1.3 mmHg, respectively. DBP was also significantly reduced by 2.2 ± 0.8 mmHg after 6 months of psyllium fibre supplementation (Cicero et al., 2007). In another study, Nurhaedar et al. (2017) reported that there was a significant reduction in SBP by 4.1% and in DBP by 9.1% after 4 weeks of honey supplementation in healthy individuals. If the present data are extrapolated for 4 months, the decrease in SBP is expected to be about −4 mmHg, which is similar to a previous study.
Based on the detailed information collected, 41.7% (five respondents) from the supplement group stated that they increased their physical activity during the intervention period. The increase in physical activity would bring the beneficial effect of reduction on SBP (Morgenstern et al., 2016). In summary, the blood pressure of the respondents in both groups was in a normal range; therefore, no lowering effect or undesirable effects were found in the 1-month study.
This study shows no effect of supplementation on the fasting blood glucose (FPG) levels in both groups after 1-month intervention period. In Pal et al.’s (2011a) study, glucose and insulin of psyllium group did not show significant change after 12 weeks supplementation (21 g/day) as compared to baseline (p-value > 0.05). Changes in insulin sensitivity would require a longer term and also the additional physiological properties of psyllium, such as the production of short-chain fatty acids (de Bock et al., 2012). Poor fermentation of psyllium in the production short-chain fatty acids as compared to other sources of dietary fiber will not improve insulin sensitivity, and this would not allow cells to use blood glucose more effectively (de Bock et al., 2012).
 | Table 1. Subjects characteristics at baseline. [Click here to view] |
Arablou et al. (2014) stated that 12 weeks of ginger supplementation (1,600 mg/day) reduced blood glucose through blockage of serotonin receptors and inhibition of intestinal glucosidase and amylase enzyme activity. In addition, the regulation of serotonin levels by hydroxycitric acid from G. cambogia will decrease plasma insulin levels and generate a satiety effect in the brain, as well as suppress the appetite (Hayamizu et al., 2003; Ohia et al., 2001; Wielinga et al., 2005; Chuah et al., 2012).
The blood glucose of the respondents in the supplement group was in a normal range; therefore, the lowering effect or undesirable effect of the supplement in a 1-month study cannot be anticipated. In summary, 1-month supplementation is not enough to improve the blood glucose of the respondents and the beneficial effect will be shown if the subjects are diabetic rather than normal respondents.
Based on the absolute change in liver function test, supplementation significantly increased AST and ALT, both at absolute and percentage change, respectively as compared to the control group. Even though some respondents showed an increase in AST and ALT, but it is still in the normal reference range. High levels of the enzymes AST (>34 U/l) and ALT (>55 U/l) are present in the liver, and it could lead to liver damage, which this condition might cause by several factors such as infective agents, autoimmune disorders, and toxins (Blann, 2014).
 | Table 2. Comparison between baseline and after 1 month within group. [Click here to view] |
The G. cambogia present in this supplement is a type of Hydroxycut product marketed for weight loss. Hydroxycut products have been associated with liver damage and one reported death, but reports on the liver toxicity of G. cambogia supplement are limited (Corey et al., 2016; Zheng and Navarro, 2015). It is an idiosyncratic form of injury, as high doses of hydroxycitric acid may be toxic to the liver. The possibility of mislabelling or adulteration with hepatotoxic herbal products is an issue in herbal-related injuries. Semwal et al. (2015) stated that regular use of G. cambogia supplementation is associated with possible liver toxicity; however, the doses that cause hepatotoxicity is still unclear.
 | Table 3. Comparison between absolute change and percentage change between groups. [Click here to view] |
Besides, long-term intake and high doses usage of hydrolyzable tannins from Q. infectoria may cause negative health effects (Sariozlu and Kivanc, 2011). In addition, multi-ingredients formulation products are associated with more possible negative effects as compared to a specific ingredient (Semwal et al., 2015). Thus, in formulating a mixture of herb supplement, the dosage is a very important element to be considered. It can be concluded that there is an undesirable effect of this supplement on liver function, even though the increases were still in the normal reference range.
Both groups showed significantly increased HDL-c, with higher percentage (23% vs. 11%) in supplement group than in the control group. Therefore, it can be concluded that there is a benefit of supplement in increasing the HDL-c with 25 g/day dosage of this supplement. A study of Ziai et al. (2005) reported that 10.2 g/day of psyllium supplementation among 57 patients with T2D showed significantly increased HDL-c (from 0.94 to 1.10 mmol/l) after 2 months of supplementation. Weight change significantly affects HDL-c concentrations, as HDL-c will increase with concurrent weight decreases (Dansinger et al., 2018). Additionally, astaxanthin can increase serum HDL-c in subjects with mild hyperlipidemia (Yoshida et al., 2010). In the present study, there was a significant reduction in BMI; this reduction in weight will significantly increase with HDL-c, and the presence of astaxanthin in the supplement may be a factor in increasing the HDL-c.
 | Table 4. Comparison of health indicator parameters between baseline and after 1 month. [Click here to view] |
There was a significant decrease in absolute change and percentage change of TC/HDL-c ratio in both groups by 0.25 (–4.58%) and 0.77 (–15.51%), respectively. In a study by Soltanian et al. (2018), TC levels were significantly reduced by 0.56 mmol/l and HDL-c levels significantly increased by 0.10 mmol/l in T2D patients after 3 months of taking psyllium (10 g premixed in cookies twice per day) supplementation as compared to the baseline. If the present data are extrapolated for 3 months, the HDL-c can be increased by 0.65 mmol/l, which is higher than the previous study. Since there were changes in TC and HDL-c level in the present data, this result indicates a significant change on TC/HDL-c ratio. The TC/HDL-c ratio in both groups was shown at risk in the baseline data.
TC/HDL-c ratio was significantly reduced to the normal reference range (<4.50) in both groups (–16% vs. –5%). The intake of plant-based diets and Mediterranean-type diets may lead to a significant decrease in TC and LDL-c since the diet is a major contributor to reducing cholesterol (Heidemann et al., 2008; Capewell and Ford, 2011). In summary, the supplement still has the potential to control the increase in TC level and demonstrated an effect in lowering the TC/HDL-c ratio.
The respondents in the supplement group have shown improvement in “tired eye” (–6% vs. +21%), “joint pain” (–6% vs. 0%), and “menstrual pain” (–17% vs. 0%) as compared to the control group. Although there was little change in health indicator parameters during the 1-month period, positive changes were observed among respondents in the supplement group, who described their condition as improved. There is a significant deficit in health indicator parameters that persisted over time. White et al. (2016) stated that it is not enough to observe a change in a 6–month intervention period when the majority of patients are not newly diagnosed with Amyloid light-chain amyloidosis, particularly in a given sample. Hence, it can be concluded that a 1-month study duration is not enough to observe the change in health indicator parameters among the respondents in the supplement group.
CONCLUSION
It can be concluded that there are beneficial effects in reducing BMI and TC/HDL-c, along with an undesirable effect on liver function tests, especially in the AST and ALT levels, which might indicate potential liver toxicity after 1-month supplementation of 25 g/day of psyllium husk and mixed herb. Future studies should increase the duration of the intervention period to seek the optimum beneficial effects of the supplement.
ACKNOWLEDGMENTS
The authors would like to express their gratitude to all the female adult respondents for their participation, full cooperation, and patience with the study.
AUTHORS’ CONTRIBUTIONS
All authors made a substantial contribution to the conception and design, acquisition of data, or analysis and interpretation of data; took part in drafting the article or revising it critically for important intellectual content; agreed to submit it to the current journal; gave final approval of the version to be published; and agreed to be accountable for all aspects of the work. All the authors are eligible as per the International Committee of Medical Journal Editors (ICMJE) requirements/guidelines.
FINANCIAL SUPPORT
There is no funding to report.
CONFLICTS OF INTEREST
The authors report no financial or any other conflicts of interest in this work.
ETHICAL APPROVALS
The present study was approved by RMIC Human Ethics Committee, Universiti Malaysia Terengganu with reference number of UMT/JKEPHMK/2020/43. Consent forms were signed and collected from all study participants.
DATA AVAILABILITY
All data generated and analysed are included within this research article.
PUBLISHER’S NOTE
This journal remains neutral with regard to jurisdictional claims in published institutional affiliation.
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