Effectiveness Not Established

Baker's Yeast

for Constipation

Baker’s yeast comprises strains of yeast commonly used as leaven in baking bread and other bakery products. Baker’s yeast was examined as a dietary supplement in patients with cancer for the treatment of opioid-induced constipation.

Research Evidence Summaries

Wenk, R., Bertolino, M., Ochoa, J., Cullen, C., Bertucelli, N., & Bruera, E. (2000). Laxative effects of fresh baker’s yeast. Journal of Pain and Symptom Management, 19, 163–164.

Study Purpose

To determine whether the consumption of fresh baker’s yeast (FBY) reduces constipation in opioid-treated patients with advanced cancer.

Intervention Characteristics/Basic Study Process

FBY is a fungus most commonly used in the kitchen for raising dough. In Argentina, FBY is available in a paste form that can be mixed with liquids and meals. It is used as both a food supplement to provide vitamins, and a bowel regulator. 

Patients initiated opioid therapy and concurrently received a daily dose of FBY in the morning for 15 days. FBY was dissolved in water at room temperature, with the option of mixing it with the patient’s favorite food. The initial dose was 6 g once a day in the morning. If patients did not have a bowel movement (BM), the dose was doubled daily until laxation occurred. The maximum dose was 50 mg. If no BM occurred within three days, a stimulant laxative was added to the treatment.  If no BM occurred within an additional two days, an enema was ordered. Results were assessed daily by phone.

Sample Characteristics

  • The study reported on a sample of 17 patients (9 men and 8 women).
  • Median patient age was 59 years.
  • Eastern Cooperative Oncology Group (ECOG) Performance Status was as follows: 1 (n = 4), 2 (n = 6), 3 (n = 4), and 4 (n = 3).
  • Tumor sites were lung (n = 6), breast (n = 3), colon (n = 3), laryngeal (n = 2), melanoma (n = 1), penal (n = 1), and adrenal (n = 1).


  • Argentina
  • Fifteen patients were treated at home.
  • Two patients were treated as inpatients.

Measurement Instruments/Methods

  • Bowel function, fecal consistency, presence of diarrhea, nausea and vomiting, and colic were recorded.
  • Demographic information, equivalent daily dose of oral morphine, and previous bowel function also were recorded.


  • Two patients withdrew from the study.
  • Results were confusing, reported as follows.
    • Eight patients had BMs daily, six patients had BMs four times daily, and one patient had BMs on the third day.
    • Four patients needed stimulant laxative in combination, two needed enemas, and one needed a glycerin suppository.
    • Fecal consistency was normal in nine patients, soft in four, and hard in the remaining two.


FBY was effective.


  • The sample size was small.
  • The taste of FBY was not tolerated by some patients.
  • FBY needs to be refrigerated and has a 30-day lifespan.
  • The follow-up was short (15 days).
  • The study lacked a control group.
  • Information concerning FBY's mechanism of action was lacking.
  • The long-term efficacy and side effects of FBY were not defined.

Nursing Implications

The cost of FBY as an intervention was low, at $2.50 per 15 days.