Absorption of supplements for endometriosis

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Supplements are valuable support and supplementation diet anti-inflammatory in case of endometriosisWhen discussing supplementation, the topic of nutrient absorption is often overlooked. However, it's crucial and determines whether our body will actually benefit from a given supplement. In this article, I'll explain what nutrient absorption is and how you can increase it to better support your body during illness. 

Absorption of supplements in endometriosis – why is it important and what influences it?

Supplement absorption is the degree to which the active ingredients in a supplement are effectively absorbed from the digestive tract and utilized by the body. The effectiveness of supplementation depends on the absorption of a given ingredient. Many factors influence absorption. Some of these are within our control and can be modified, while others are beyond our control. The most important factors affecting supplement absorption are:

  • Chemical form of vitamins and minerals: Different chemical forms of the same vitamin or nutrient can have completely different bioavailability. It's not enough to supplement with "some magnesium" or "some vitamin B12." To fully utilize their potential, we must choose these nutrients in appropriate, easily absorbed chemical forms. 
  • Interactions: Dietary supplement ingredients interact with numerous factors, including other supplements, dietary components, and medications. Therefore, supplements and their administration should be carefully considered and planned to reduce the risk of adverse interactions. 
  • Digestive health: Absorption of nutrients occurs in the intestines, so if you want to fully utilize the potential of your diet and supplementation, you need to take care of the health of your digestive tract. If you struggle with problems such as irritable bowel syndrome, sibo, gastritis, it is worth treating them first and only then starting supplementation for endometriosis. 

Vitamins for endometriosis – what affects their absorption?

Supplementing certain vitamins with endometriosis can help prevent deficiencies, support the body in combating chronic inflammation, and positively impact fertility and daily well-being. Below, you'll find a list of the most commonly used vitamins for endometriosis, along with tips for optimizing their absorption.

  • Vitamin D: Vitamin D is fat-soluble, so it's recommended to take it with a meal, as this can increase its absorption. Calcium and magnesium also have a beneficial effect on its absorption. Above all, avoid deficiencies and ensure adequate intake through your diet. This will make vitamin D supplements more absorbable. However, if you also need to supplement calcium or magnesium, you can combine these supplements with vitamin D supplements. 
  • Vitamin E: Like vitamin D, vitamin E is also fat-soluble, so it is recommended to take it with a meal. The most active form is alpha-tocopherol and this is the form worth looking for in supplements. Vitamin E can be combined with other antioxidant ingredients, e.g. selenium or vitamin C. 
  • Folates: an adequate supply of folates is important not only before and during pregnancy, but for every woman with endometriosis, regardless of reproductive plans. If you supplement folate, you can take it along with other B vitamins, especially B12, B6, and B4, for optimal absorption. Additionally, remember that the main factor reducing folate absorption is alcohol consumption. The chemical form is also important. Choose supplements with active (methylated) folic acid and avoid those with pteroylmonoglutamic acid, which is a synthetic form. Look for folate, 5-MTHF, or Quatrefolic® in the ingredient list—the latter of which we used in our supplement. EndoBase.
  • Vitamin B12: If you supplement with vitamin B12, make sure your supplement contains methylcobalamin. This is an active, safe, and highly bioavailable form. However, the absorption of B12 may be reduced by large doses of vitamin C (therefore, keep a distance if you supplement these two nutrients), as well as some medications, especially metformin. Alcohol consumption also has a negative impact. Stomach diseases can also impair B12 absorption because they disrupt the production of Castle's factor by stomach cells, which is essential for the proper metabolism of this vitamin. 

Minerals in endometriosis – what affects their absorption?

We have discussed the absorption of vitamins, so now it is time to discuss minerals that may potentially support endometriosis. 

  • Magnesium: It's one of the most commonly used minerals in the context of endometriosis, and its chemical form has the greatest impact on its bioavailability. Unfortunately, many supplements contain magnesium oxide. This ingredient has very low bioavailability and is therefore not recommended. Supplements containing magnesium in the form of citrate, taurate, threonate, malate, or glycinate are a better choice. Vitamin B6 and vitamin D also have a positive effect on the absorption of magnesium. 
  • Iron: Heavy menstrual bleeding and chronic inflammation in endometriosis may increase iron demand and necessitate periodic iron supplementation. The absorption of iron supplements depends, among other things, on our diet. It's most often recommended to take it on an empty stomach or between meals, as dietary fiber and calcium from meals can reduce its absorption. Coffee and tea also have a negative effect. The polyphenols they contain significantly impede the body's utilization of iron. Vitamin C and organic acids, on the other hand, have a positive effect. Therefore, it's worth including fresh vegetables and fruits in your diet, as well as fermented and fermented dairy products.
  • Selenium: selenium is a strong antioxidant and has anti-inflammatory effects, so it's worth considering as part of a periodic supplementation for endometriosis. To fully utilize its potential, ensure high bioavailability by choosing supplements with L-selenomethionine and combining it with vitamin C and vitamin E. Adequate protein intake and avoiding alcohol are also important. 

Active ingredients for endometriosis – what affects their absorption?

Many supplements recommended for endometriosis, in addition to vitamins and minerals, also contain plant-derived substances and other active ingredients with anti-inflammatory properties. Some of these, such as N-acetylcysteine ​​(NAC) and epigallocatechin gallate (EGCG), are characterized by high bioavailability and do not require additional interventions to increase it. A supplement with a potentially positive effect on endometriosis, but with relatively poor bioavailability, is curcumin. Piperine, on the other hand, enhances its bioavailability, which is why many supplements combine these two substances. We also used this combination in our supplement. EndoBase

Summary

Supplementation in endometriosis can be supportive in alleviating symptomsVitamins D, C, and E, magnesium, as well as NAC and curcumin, play a key role. The effectiveness of supplements depends on their bioavailability and chemical form. Therefore, just any supplement isn't enough. Supplementation should be carefully considered and spaced throughout the day to reduce the risk of negative interactions and ensure optimal bioavailability and effectiveness. 

Źródła:

  1. Guo J. Association between dietary selenium intake and endometriosis risk: a cross-sectional analysis, https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2025.1486790/full [accessed: 17/09/2025]
  2. vitamin E, https://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional/[accessed: 17/09/2025]
  3. Interactions, https://www.ncbi.nlm.nih.gov/books/NBK216072/ [accessed: 17/09/2025]
  4. Folate, https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/[accessed: 17/09/2025]
  5. Vitamin D, https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/  [accessed: 17/09/2025]
  6. Magnesium, https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/ [accessed: 17/09/2025]
  7. Cas M. Dietary Curcumin: Correlation between Bioavailability and Health Potential, https://pmc.ncbi.nlm.nih.gov/articles/PMC6770259/ [accessed: 17/09/2025]
  8. selenium, https://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/ [accessed: 17/09/2025]
  9. Krebs N. Bioavailability of dietary supplements and impact of physiologic state: infants, children and adolescents, https://pubmed.ncbi.nlm.nih.gov/11285353/ [accessed: 17/09/2025]

Aleksandra Dziura

A clinical dietitian, she graduated from the Medical University of Warsaw (undergraduate and graduate studies) and the Institute of Performance Nutrition. She continually expands her knowledge of women's health and nutrition by participating in conferences in Poland and abroad. She takes a holistic approach to working with patients, seeking the root cause of problems rather than simply masking symptoms. For over five years, she has been working with women with endometriosis and adenomyosis.

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