Dietary supplements for treatment of endometriosis: A review

Study of the association of niacin and vitamin B6 intake with endometriosis: Evidence from NHANES 2003-2006

OBJECTIVE

This study aims to investigate the association between dietary intake of niacin and vitamin B6 and the prevalence of endometriosis using data from the National Health and Nutrition Examination Survey (NHANES) 2003-2006.

METHODS

We conducted a cross-sectional analysis using data from women aged 25-45 years in the 2003-2006 NHANES. Niacin and vitamin B6 intake were assessed using 24-h dietary recalls, and endometriosis status was determined by self-report. Covariates included age, race, body mass index, poverty income ratio, smoking status, and alcohol consumption. Weighted logistic regression models were used to evaluate the association between vitamin intake and endometriosis, with stratified analyses performed for different age groups. Data visualization included scatter plots with locally estimated scatterplot smoothing (LOESS) curves to illustrate the relationship between nutrient intake and the probability of endometriosis.

RESULTS

A total of 1467 participants were included, of whom 7.17% (105 individuals) reported having endometriosis. There were significant differences in dietary intake of niacin and vitamin B6 between participants with and without endometriosis. In the unadjusted model, vitamin B6 intake was significantly negatively associated with endometriosis (odds ratio [OR], 0.79 [95% confidence interval (CI), 0.62-0.99], P = 0.033), and niacin intake showed a marginally significant negative association (OR, 0.98 [95% CI, 0.96-1.00], P = 0.019). In the models adjusted for age and race, the negative association between vitamin B6 and endometriosis remained significant (OR, 0.80 [95% CI, 0.63-1.01], P = 0.044), and the association for niacin remained marginally significant (OR, 0.98 [95% CI, 0.96-1.00], P = 0.023). In the fully adjusted model, the negative association for vitamin B6 remained significant (OR, 0.79 [95% CI, 0.63-0.99], P = 0.033), and the association for niacin remained marginally significant (OR, 0.98 [95% CI, 0.96-1.00], P = 0.021). Age-stratified analysis showed that niacin intake was not significantly associated with endometriosis in women aged 35 years and younger (OR, 0.98 [95% CI, 0.95-1.02], P = 0.3), whereas vitamin B6 intake was significantly negatively associated with endometriosis in women older than 35 years (OR, 0.75 [95% CI, 0.56-0.99], P = 0.048). Scatter plots with LOESS curves indicated a negative trend between higher intakes of niacin and vitamin B6 and the probability of endometriosis.

CONCLUSIONS

The findings suggest that dietary vitamin B6 intake is negatively associated with the prevalence of endometriosis, particularly among women older than 35 years, highlighting the potential role of dietary adjustments in managing endometriosis. Niacin intake also showed a protective effect, although this was less pronounced than vitamin B6. These results provide a basis for further research into the relationship between diet and endometriosis.

Association Between Composite Dietary Antioxidant Index and Endometriosis from NHANES 2001-2006: A Cross-Sectional Study

Purpose

To evaluate the association between Composite Dietary Antioxidant Index (CDAI) and the risk of endometriosis in American women.

Methods

The study adopted a cross-sectional design, incorporating 3862 women aged over 20 years, selected from the National Health and Nutrition Examination Survey (NHANES) dataset from 2001 to 2006. Six dietary antioxidants were taken into account in calculating CDAI. Endometriosis was determined based on self-report. To evaluate the association between CDAI and the risk of endometriosis, we employed models with multivariable logistic variables. For subgroup assessment in relation to CDAI, a stratified multivariate logistic regression model was utilized.

Results

Among all participants, 273 participants (7.1%) were found to exhibit endometriosis. The preliminary analysis showed a reverse association between CDAI and the likelihood of endometriosis (odds ratio [OR] = 0.95; 95% confidence interval [CI]: 0.92~0.98). Upon full adjustment within the multivariable logistic regression, the ORs (95% CI) for endometriosis prevalence per unit increase in CDAI were estimated to be 0.96 (0.93~1). When the CDAI levels were divided into quartiles, it was found that the ORs for endometriosis with CDAI levels in Q2 (-2.131-0.023), Q3 (0.023-2.650), and Q4 (2.650-42.854) were 0.74 (0.52, 1.05), 0.76 (0.53, 1.1), and 0.53 (0.36, 0.79), respectively, compared to those with CDAI levels in Q1 (-7.151--2.131). We evaluated the association between CDAI and endometriosis using subgroups stratified by age, race/ethnicity, education level, body mass index (BMI), oral contraceptive, and menopausal status, revealing a substantial negative relationship.

Conclusion

In this cross-sectional study, increasing CDAI was proportionally associated with a reduced risk of endometriosis among American women, suggesting a diet high in antioxidants may play an important role in reducing the risk of endometriosis. The findings of NHANES data spanning 2001 to 2006 suggest that promoting antioxidant-rich diets could be an important prevention strategy for endometriosis.

The association between vitamin intake and endometriosis: a cross-sectional study of the NHANES 1999-2006

BACKGROUND

Endometriosis is a common cause of female reproductive problems, and vitamin intake may affect its incidence. Therefore, we further explored the association between multivitamin intake and endometriosis in a large population-based study.

METHODS

This study included 3351 participants from the National Health and Nutrition Examination Survey (NHANES) 1999-2006. The dietary intake of eight vitamins was calculated as the average of two 24-h recall interviews, and information on endometriosis was obtained through questionnaires that included gynecological history. Multiple logistic regression analysis was used to explore the relationship between multivitamin intake and endometriosis. Smoothed curve fitting analysis was employed to assess the dose-response relationship between vitamins and endometriosis. Finally, subgroup analysis and interaction tests were conducted to determine the association of covariates between vitamins and endometriosis.

RESULTS

In this large-scale cross-sectional study, multiple logistic regression analysis showed that the intake of vitamins A, B1, B2, B6, C and folate was negatively associated with the occurrence of endometriosis. The odds ratios associated with a per-SD increase were 0.836 (95%CI: 0.702, 0.997), 0.817 (95%CI: 0.702, 0.951), 0.860 (95%CI: 0.746, 0.991), 0.784 (95%CI: 0.669, 0.919), 0.845 (95%CI: 0.718, 0.994), and 0.772 (95%CI: 0.660, 0.903), respectively. Smoothed curve fitting analysis revealed that the intake of vitamins A, B1, B2, B6, C, and folate was negatively associated with the risk of endometriosis (P < 0.05). Vitamin E showed a saturating effect, with an optimal cutoff point at 13.18. Below this cutoff, the intake of vitamin E was negatively correlated with the risk of endometriosis (OR = 0.947, 95% CI: 0.906, 0.989), whereas above the cutoff, there was no significant correlation between vitamin E intake and the risk of endometriosis (OR = 1.001, 95% CI: 0.997, 1.005).

CONCLUSIONS

The results of this study indicate a significant linear negative correlation between the intake of vitamins A, B1, B2, B6, C, and folate, and the risk of endometriosis, and reveal a threshold effect for vitamin E intake on the risk of endometriosis. These findings could inform clinical dietary interventions and may support the development of preventive strategies for endometriosis, potentially aiding in its reduction.

Influence of Mediterranean Diet on Sexual Function in People with Metabolic Syndrome: A Narrative Review

Metabolic syndrome (MS), a cluster of cardiometabolic disorders, and sexual dysfunction are two conditions that impact a large proportion of the general population. Although they can occur independently, they are frequently linked and significantly affect people's quality of life. In recent years, research has increasingly focused on the importance of diet, particularly the Mediterranean diet (MD), in modulating sexual function due to its anti-inflammatory, antioxidant, and vasodilatory properties. In this narrative review, we examined the relationship between MS and sexual function in both men and women, with a special emphasis on the MD's therapeutic efficacy in improving sexual dysfunction. In men, MD has been shown to ameliorate erectile dysfunction, as well as several sperm parameters, perhaps leading to improved fertility. On the other hand, adherence to MD has been demonstrated to partially recover several sexual dysfunctions in women, such as those related to their menstrual cycle, menopause, endometriosis, and polycystic ovary syndrome. These favorable effects of MD have been demonstrated in both sexes also among people affected by MS. However, more targeted studies are needed to validate these data for different dietary approaches as well.

The Association Between Daily Intake of Dietary Supplements and Self-Reported Endometriosis: A NHANES-Based Study

Dietary supplements are gaining recognition as potential influencers of female reproductive health, but their connection to endometriosis risk remains underexplored. This study addressed this gap, examining the impact of daily dietary supplement intake on the initiation and progression of endometriosis. To explore this, a cross-sectional study was conducted involving 3950 participants representative of the US population from the 1999-2006 National Health and Nutrition Examination Survey (NHANES). Infertility was determined by a question on year-long attempts to become pregnant. Unweighted and weighted multivariate logistic regression analyses assessed the association between dietary supplements and endometriosis risk. Subgroup analysis was conducted based on the participants' body mass index (BMI). The results revealed intriguing patterns. Specifically, higher dietary fiber content (Q4 vs Q1: OR = 0.56, 95% CI = (0.37,0.84), P = 0.0062) and density (Q4 vs Q1: OR = 0.55, 95% CI = (0.38,0.81), P = 0.0035) were linked to reduced risk of endometriosis. Protein content (Q4 vs Q1: OR = 0.47, 95% CI = (0.31,0.74), P = 0.0011) and density (Q4 vs Q1: OR = 0.63, 95% CI = (0.45,0.88), P = 0.0096) similarly exhibited a negative association with endometriosis risk. Interestingly, when stratified by BMI, these effects were pronounced in normal-weight women, whereas they were not evident in the overweight and obese subgroup. Protein content and density showed no significant associations across subpopulations. In conclusion, this study established a negative relationship between dietary fiber and endometriosis, particularly notable in normal-weight women. Future research is essential to validate these findings and establish a causal link between dietary fiber and endometriosis.

Effects of the gut microbiota and its metabolite short-chain fatty acids on endometriosis

In recent years, a growing body of research has confirmed that the gut microbiota plays a major role in the maintenance of human health and disease. A gut microbiota imbalance can lead to the development of many diseases, such as pregnancy complications, adverse pregnancy outcomes, polycystic ovary syndrome, endometriosis, and cancer. Short-chain fatty acids are metabolites of specific intestinal bacteria and are crucial for maintaining intestinal homeostasis and regulating metabolism and immunity. Endometriosis is the result of cell proliferation, escape from immune surveillance, and invasive metastasis. There is a strong correlation between the anti-proliferative and anti-inflammatory effects of short-chain fatty acids produced by gut microbes and the development of endometriosis. Given that the mechanism of action of gut microbiota and Short-chain fatty acids in endometriosis remain unclear, this paper aims to provide a comprehensive review of the complex interactions between intestinal flora, short-chain fatty acids and endometriosis. In addition, we explored potential microbial-based treatment strategies for endometriosis, providing new insights into the future development of diagnostic tests and prevention and treatment methods for endometriosis.

Diagnostic and therapeutic approaches for endometriosis: a patent landscape

OBJECTIVE

The aim of this review is to analyze the patent filings and to systematize the main technological trends in patent protection for the diagnosis and therapeutics for endometriosis. Patent literature has also been explored to identify active inventors and applicants in this field.

METHODOLOGY

Patent search was carried out in the freely accessible patent search databases namely, patentscope using various combinations of the keywords "Endometriosis OR Adenomyosis" AND "Diagnostic OR Therapeutics" were used along with wildcard search queries in the "Title", "Abstract" and "Descriptions" fields.

RESULTS

A patent search revealed 144 patents describing inventions for diagnostic and therapeutic purposes of endometriosis. These patents include 26 patent applications in the diagnostic utility and 116 patent applications under the therapeutic approaches. Out of these 116 patent applications, 43 describe traditional medicines for endometriosis. Two patent applications describe inventions that can fall into both categories.

CONCLUSION

Efforts are being made to improve current diagnostic instruments. Hormonal alteration methods is the most common field of invention, followed by surgical interventions for therapeutics. A general trend of increase in patent application filings has been observed with a slight decrease in recent years.

Effect of curcumin on painful symptoms of endometriosis: A triple-blind randomized controlled trial

Endometriosis is one of the most common gynecological disorders. This study aimed to determine the effect of curcumin on painful symptoms of endometriosis and the quality of life in affected women. This randomized controlled trial was conducted on 68 women with endometriosis referred to Shahid Beheshti Infertility Center in Isfahan, Iran, 2022. The participants were allocated to intervention (n = 34) and control (n = 34) groups by the blocked randomization method. Curcumin capsules with a dose of 500 mg were given to the intervention group twice a day for 8 weeks, and the placebo with the same dose was given to the control group. The questionnaires of Endometriosis Health Profile, painful symptoms of endometriosis, and visual analogue scale were used to collect data. Independent t, ANCOVA, and Mann-Whitney U-tests were used to compare the outcomes between the study groups. After the intervention, based on the ANCOVA with the adjusting of the baseline values and Mann-Whitney U-test, there was no statistically significant difference in the amounts of usual pain (p = 0.496) and pain at its worst (p = 0.320), quality of life (p = 0.556), and visual pain (p = 0.845). The results showed that using curcumin does not affect the painful symptoms and quality of life of women with endometriosis. Future clinical trials are needed to investigate and highlight the role of curcumin in endometriosis.

[Holistic treatment of endometriosis]

BACKGROUND

The pain phenomena caused by endometriosis are manifold. In addition to nociceptive pain there is also a nociplastic reaction with central sensitization. Atypical symptoms, such as acyclic lower abdominal pain, radiating pain, nonspecific bladder and intestinal complaints or even depression increasingly occur in addition to the classical cyclic complaints, such as severe dysmenorrhea, cyclic lower abdominal pain, dyspareunia, dysuria and dyschezia. Due to the diffuse range of symptoms, affected patients often consult not just gynecologists but also specialists from other disciplines (internal medicine, gastroenterology, orthopedics, pain therapy, psychology etc.).

OBJECTIVE

The complexity of endometriosis is presented. The resulting approaches to multimodal interdisciplinary holistic treatment are described.

RESULTS

Interdisciplinary concepts should be involved in the optimal treatment of endometriosis patients along with hormonal and surgical treatment, mostly under the supervision of a gynecologist and pain management, dietary changes, psychological support and physiotherapeutic management should also be included. This article provides an overview of possible treatment strategies for chronic symptomatic endometriosis.

CONCLUSION

Based on multimodal treatment strategies and regarding the complex pathophysiological alterations of this disease, the complex complaints that significantly impair the quality of life of endometriosis patients can be greatly improved.

The Laboratory and Clinical Perspectives of Magnesium Imbalance

Magnesium (Mg2+) is a predominantly intracellular cation that plays significant roles in various enzymatic, membrane, and structural body functions. As a calcium (Ca2+) antagonist, it is imperative for numerous neuromuscular activities. The imbalance of body Mg2+  concentration leads to clinical manifestations ranging from asymptomatic to severe life-threatening complications. Therefore, the contribution of Mg2+ measurement regarding various laboratory and clinical aspects cannot be ignored. Mg2+ is often described as the forgotten analyte. However, its close relationship with body potassium (K+), Ca2+, and phosphate homeostasis proves that Mg2+ imbalance could co-exist as the root cause or the consequence of other electrolyte disorders. Meanwhile, several preanalytical, analytical, and postanalytical aspects could influence Mg2+ measurement. This review highlights Mg2+ measurement's laboratory and clinical issues and some analyte disturbances associated with its imbalance. Understanding this basis could aid clinicians and laboratory professionals in Mg2+ result interpretation and patient management.

Association of fertility diet score with endometriosis: a case-control study

Background and aims

Different factors, such as environmental, epigenetic, genetic and immunological, have been identified as potential risks for developing endometriosis. However, the correlation between dietary patterns and endometriosis is currently unknown. The aim of this study was to explore the potential link between fertility diet score and the odds of endometriosis.

Methods

This study was a hospital-based case-control study that took place in a gynecology clinic in Tehran, Iran, between February 2021 and January 2022. A total of 107 newly diagnosed endometriosis cases and 210 controls were included. The participants' habitual diets were evaluated using a food frequency questionnaire, and their fertility diet score was estimated using a point system based on Chavarro et al.'s criteria. The logistic regression was utilized to calculate the odds ratios (OR) with 95% confidence intervals (CIs).

Results

The study found that women who adherence to fertility diet have a lower odds of endometriosis. This was observed in both the base model and the adjusted model, with a significant decrease in odds of endometriosis by 66% (OR = 0.44, 95%CI = 0.27-0.71, p = 0.001) and 54% (aOR = 0.46, 95%CI = 0.23-0.90, p = 0.022), respectively. Additionally, consuming vegetable proteins and multivitamins were also associated with lower odds of endometriosis. On the other hand, consuming animal proteins, heme iron, and having a high glycemic load were associated with significantly higher odds of endometriosis.

Conclusion

Our research supports the hypothesis that following a fertility diet may decrease the odds of endometriosis in Iranian women. However, these findings should be verified through extensive, prospective studies.

Flavonoids Quercetin and Kaempferol Are NR4A1 Antagonists and Suppress Endometriosis in Female Mice

Nuclear receptor 4A1 (NR4A1) plays an important role in endometriosis progression; levels of NR4A1 in endometriotic lesions are higher than in normal endometrium, and substituted bis-indole analogs (NR4A1) antagonists suppress endometriosis progression in mice with endometriosis. In addition, the flavonoids kaempferol and quercetin are natural products that directly bind NR4A1 and significantly repress the intrinsic NR4A1-dependent transcriptional activity in human endometriotic epithelial and stromal cells and Ishikawa endometrial cancer cells. NR4A1 knockdown and inhibition of NR4A1 by kaempferol and quercetin suppressed proliferation of human endometriotic epithelial cells and Ishikawa cells by inhibiting epidermal growth factor receptor/c-Myc/survivin-mediated growth-promoting and survival pathways, The mammalian target of rapamycin (mTOR) signaling and αSMA/CTGF/COL1A1/FN-mediated fibrosis signaling but increasing Thioredoxin domain Containing 5/SESN2-mediated oxidative/estrogen receptors stress signaling. In human endometriotic stromal cells, NR4A1 knockdown and inhibition of NR4A1 by kaempferol and quercetin primarily inhibited mTOR signaling by suppressing proliferation of human endometrial stromal cells. In addition, kaempferol and quercetin treatment also effectively suppressed the growth of endometriotic lesions in mice with endometriosis compared with the vehicle without any body weight changes. Therefore, kaempferol and quercetin are NR4A1 antagonists with potential as nutritional therapy for endometriosis.

Gut and reproductive tract microbiota: Insights into the pathogenesis of endometriosis (Review)

Endometriosis is characterized by the presence of endometrial-like tissue outside the uterus and is associated with an inflammatory immune response. The gut and reproductive tract microbiota constitute a protective barrier against infection by pathogens and regulate inflammatory and immune functions. This review summarizes microbiota imbalance (i.e., dysbiosis) in endometriosis and discusses how dysbiosis influences disease development. The literature was searched for studies published from inception to March 2022 in the PubMed and Google Scholar databases using a combination of specific terms. An altered gut and reproductive tract microbiome has been reported in numerous conditions, such as inflammatory bowel disease, allergies, autoimmunity, cancer and reproductive disorders (e.g., endometriosis). Furthermore, microbial dysbiosis is a hallmark of endometriosis and is characterized by a decrease in beneficial probiotics and an increase in pathogenic microbes, which leads to a series of estrobolomic and metabolomic changes. Gut or reproductive tract microbiome dysbiosis was reported in mice, nonhuman primates, and females with endometriosis. Animal models of endometriosis demonstrated the effects of the gut microbiome on lesion growth and vice versa. The immune system mediated by the microbiota-gut-reproductive tract axis triggers an inflammatory response that damages reproductive tract tissue, which possibly leads to endometriosis. However, whether the alteration of eubiosis (a balanced microbiota) to dysbiosis is a cause or a result of endometriosis is unclear. In conclusion, this review provides an overview of the relationship between the gut and reproductive tract microbiome and endometriosis, focusing on the mechanisms by which dysbiosis may increase the risk of disease.

The role of zinc in follicular development

Follicles consist of specialized somatic cells that encase a single oocyte. Follicle development is a process regulated by a variety of endocrine, paracrine, and secretory factors that work together to select follicles for ovulation. Zinc is an essential nutrient for the human body and is involved in many physiological processes, such as follicle development, immune response, homeostasis, oxidative stress, cell cycle progression, DNA replication, DNA damage repair, apoptosis, and aging. Zinc deficiency can lead to blocked oocyte meiotic process, cumulus expansion, and follicle ovulation. In this mini-review, we summarize the the role of zinc in follicular development.

The gut microbiota and endometriosis: From pathogenesis to diagnosis and treatment

Endometriosis is a common gynecological disease, that often leads to pain and infertility. At present, the specific pathogenesis of endometriosis has not been clarified, but it may be closely related to an imbalance of sex hormones in the body, ectopic hyperplasia stimulated by immune inflammation, and invasion and escape based on tumor characteristics. Gut microbiota is associated with many inflammatory diseases. With the further study of the gut microbiota, people are paying increasing attention to its relationship with endometriosis. Studies have shown that there is an association between the gut microbiota and endometriosis. The specific ways and mechanisms by which the gut microbiota participates in endometriosis may involve estrogen, immune inflammation, and tumor characteristics, among others. Therefore, in the future, regulating gut microbiota disorders in various ways can help in the treatment of endometriosis patients. This study reviewed the research on the gut microbiota and endometriosis in order to provide ideas for clinical diagnosis and treatment.