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This month's highlights

Dr Jim McMorran BM BCh PhD DCH DRCOG MRCGP FRCGP

In this month’s email, I consider new evidence on calcium consumption (including from yoghurt) and reduction in colorectal cancer risk.

Evidence from a prospective study that tracked the intake of 97 dietary factors in 542,778 women from 2001 for an average of 16.6 years showed that calcium intake had the strongest protective effect against the development of colorectal cancer, with each additional 300 mg per day – equivalent to a large glass of milk – associated with a 17% reduction in risk. Six dairy-related factors associated with calcium – dairy milk, yoghurt, riboflavin, magnesium, phosphorus and potassium intakes – also demonstrated inverse associations with colorectal cancer risk.

Also of note was that alcohol showed the reverse association, with each additional 20 g daily consumption – equivalent to one large glass of wine – being associated with a 15% increased risk of colorectal cancer. Weaker associations were seen for the combined category of red and processed meat, with each additional 30 g/per day being associated with an 8% increased risk for colorectal cancer.

The study authors concluded that dairy products help protect against colorectal cancer, and that this is driven largely or wholly by calcium.

Further evidence has shown the benefit of yoghurt consumption with respect to a reduction in the risk of development of colorectal cancer – in particular reduced risk of development of proximal colorectal cancer.

There is evidence indicating that probiotics such as yoghurt may play a cancer-preventative role via their effect on the intestinal microbiota composition and/or intestinal barrier function.

For more information, please see Primary Care Notebook.

Other highlights in this month’s email include an update of the vitamin B12 deficiency section, information on analgesia in pregnancy available to primary care and an update of the lichen sclerosus section.

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