A new US study suggests intermittent fasting may offer a potential path for reducing the risk of breast cancer.
Researchers at University of California’s San Diego School of Medicine reported time-restricted feeding (TRF) improves insulin levels and reduces tumour growth in mice with obesity-driven post-menopausal breast cancer.
It followed their initial findings that:
- tumour growth was driven and accelerated by elevated insulin levels in the mice; and
- lowering the mice’s insulin levels and improving their metabolic health had an anti-tumour effect.
Lead author Dr Manasi Das told medicalnewstoday.com: ‘Time-restricted eating (TRE) has a positive effect on metabolic health and does not trigger the hunger and irritability associated with long-term fasting or calorie restriction.
‘Through its beneficial metabolic effects, TRE may also provide an inexpensive, easy-to-adopt but effective strategy to prevent and inhibit breast cancer without requiring a change in diet or physical activity.’
Previous research has shown obesity increases risks of developing at least 13 types of cancer – obesity seeming to disrupt circadian rhythms:
- causing changes to how the body responds to insulin (the hormone which helps regulate blood sugar levels) and becoming insulin resistant, which risks developing chronic diseases such as cancer;
- promoting tumour growth by interfering with the cell cycle and activity of cells that suppress tumour growth.
Other recent research at the University of Miami found a strong connection between obesity and breast cancer – with menopausal status especially important.
This latest study, reported in the journal Nature Communications, investigated whether TRF would impact growth and development of tumours and reduce risk of breast cancer metastasising to the lungs in mice with obesity-driven breast cancer.
To do this, they caused female mice to develop hormonal conditions similar to those women experience following menopause, and broke the mice into groups with varying access to high fat foods.
The team found TRF ‘seemed to reduce obesity-enhanced breast tumour growth without reducing caloric intake’, as well as reducing both risk of developing breast cancer and risk of it spreading to the lungs.
They said these results are likely due to the fact TRF ‘improved circadian disruptions and metabolic problems associated with obesity’.
Fellow author Professor Nicholas Webster summed up: ‘We were able to increase insulin sensitivity, reduce hyper-insulinemia, restore circadian rhythms and reduce tumour growth by simply modifying when and for how long mice had access to food.’
And Dr Dias added: ‘Our data suggests a person may benefit from simply timing their meals differently to prevent breast cancer rather than changing what they eat.’
