Randomised trial, 1988
Does a low-fat diet reduce symptoms of cyclical breast pain?
Yes. After 6 months on a low-fat diet, women had significant reduction in premenstrual breast tenderness and swelling. On physical exam, 6 of 10 women in the diet group showed improvement compared to 2 of 9 in the control group.
What they did
21 women with severe cyclical breast pain lasting at least 5 years were randomly assigned to either a control group (general diet advice) or an intervention group (low-fat diet at 15% of calories, with more complex carbohydrates). Both groups kept food records, had hormone and lipid measurements, and recorded symptoms daily for 6 months.
What they found
The low-fat diet group had significantly reduced premenstrual breast tenderness and swelling. On physical examination, 6 of 10 women in the diet group showed reduced breast swelling, tenderness, and nodularity, compared to 2 of 9 in the control group.
What it means for you
A low-fat diet may reduce cyclical breast pain. The study was small and focused only on breast symptoms, not general PMS. We don't know if the benefit lasts longer than 6 months or applies to other menstrual cycle symptoms.
21
Women enrolled
6 of 10
Diet group improved on physical exam
2 of 9
Control group improved on physical exam
About the study
- Original title
- Effect of a low-fat high-carbohydrate diet on symptoms of cyclical mastopathy
- Authors
- Boyd NF, McGuire V, Shannon P et al.
- Journal
- Lancet (London, England)
- Year
- 1988
- Study design
- Randomised trial
- Participants
- 21
- What was tested
- Low-fat diet at 15% of calories from fat with increased complex carbohydrates
- Read the paper
- doi.org/10.1016/s0140-6736(88)90684-8
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