The aim of the study is to determine the factors affecting the bioavailability of iron and folic acid during the simultaneous use of iron supplements and folic acid supplements in non-pregnant women of childbearing age.

Scientists in the field of nutrition and gynecology and obstetrics have been paying attention to the need of use iron and folate supplements in women of childbearing age. Increased intake of micronutrients in the diet or the use of supplementation does not always bring the expected results, what depends on factors that affect the bioavailability of minerals and vitamins. On the one hand these factors are related to the properties of food intake, e.g. to the presence of other nutrients that can increase or decrease the absorption of folates and iron (eg vitamin C, phytates), and on the other hand the functioning of the body itself, which to a certain extent is determined by genetic factors (e.g., genetically determined reduced activity of methylenetetrahydrofolate reductase [MTHFR], which reduces the bioavailability of folic acid).

The study aims:

• assessment of the effect of simultaneous supplementation with iron and folate on:

  • parameters of the iron metabolism
  • parameters of the folate metabolism

• the estimation of gene polymorphisms encoding proteins transporting iron and folate

• obtaining information whether the polymorphism of genes encoding proteins transporting iron and folate is related to the effectiveness of the iron and folic acid supplementation used in non-pregnant women of childbearing age.

In 200 non-pregnant women of childbearing age a blood level of iron and folic acid will be determined. Subjects with low level of blood iron and folic acid will be supplemented with oral iron and folic acid for 3 months. Subjects with proper level of blood iron and folic acid will be a control group. At baseline and at completion of the study (after 3 months) fasting blood will be collected and abovementioned parameters will be estimated.

Inclusion Criteria:

• age 18 to 35 years
• stable body weight (< 3 kg self-reported change during the previous three months)
• written informed consent to participate in the study,
• regular menstrual period;
• regular diet

Exclusion Criteria:

• history of use of any dietary supplements within the one month prior to the study containing iron or folic acid
• clinically relevant acute or chronic inflammatory disease in the respiratory, gastrointestinal or genitourinary system or in the mouth, throat, paranasal sinuses and / or connective tissue disease, arthritis;
• simultaneous participation in a study that affects body weight or use of diet / medication / nutritional behaviors affecting body weight;
• a history of infection in the month prior to the study
• nicotine, drug or alcohol abuse
• vegetarian diet;
• pregnancy or lactation
• other condition that, in the opinion of the investigators, would make participation not in the best interest of the patient or could prevent, limit, or confound the study results

female gender based on self-representation