Breast cancer is the most frequent tumor in Western women. In Spain about 26,000 new breast cancers are diagnosed each year. This type of tumor is increasing worldwide with an increase in aggressive neoplasms in young women. There are some risk factors responsible for this global increase: lifestyle, diet and body weight especially in postmenopausal women.

Some cell mutations, especially in the BRCA1, BRCA2 and p53 genes, are associated with a very high risk of this type of cancer. Some authors have calculated the contribution of various modifiable risk factors to the global burden of breast cancer, and they concluded that 21% of all breast cancer deaths are attributable to alcohol consumption, overweight and obesity, and lack of physical activity. Nowadays, there aren't specific studies in the Community of Madrid designed to know the risk factors related to breast cancer.

For this reason, it is proposed to carry out an observational study that collects detailed information about dietary habits, genetic factors and life quality of a group of women with recent diagnosis in pre or post-surgical phase.

1. Storage of biological sample at the Hospital.
2. Patient's breast pathology characteristics.
3. Study of concomitant pathologies.
4. Dietary study: "Frequency of Food Consumption" questionnaire referring to the last year eating habits before having been breast cancer diagnosed.
5. Physical activity study in the year prior to the diagnosis of breast cancer.
6. Anthropometric study: weight, size, waist circumference and body composition (% Fat mass,% Lean mass,% Body water).
7. Study of other risk factors of breast cancer: age, family history, reproductive history, medications consumed...
8. Biochemical study: biochemical variables of the last blood analysis performed on the volunteer in the hospital center.
9. Saliva collection to proceed with the genetic analysis.
10. Collection of stool sample to carry out the microbiota study.

Inclusion Criteria:

• Older women than 18 years old

• Newly diagnosed patients with a breast tumor (Phase I, II or III). Being in one of the following cases:

  1. Patient who has not yet received any treatment and the committee has decided that as a first treatment will receive chemo or radiotherapy.
  2. Patient who has just undergone surgery and is waiting to start adjuvant treatment with chemo or radiotherapy.

• Sign the informed consent.

Exclusion Criteria:

• Patients with stage IV disease.
• Associated Eating Disorders.
• Patients with dementia, mental illness or decreased cognitive function.
• Pregnant or lactating women.

Women with a recent diagnosis of breast cancer