This week a study came out suggesting that 25g per day of processed meat and or 50g per day of red meat can contribute to the risk of bowel cancer. It might seem that there’s a new scare mongering headline every week. Whilst we shouldn’t take each headline as hard fact there are often important messages which we can take away from the studies.
Before I give you the take home messages I want to give you a little bit of background information on the study. The study was conducted on nearly 500,000 people this is a really good population number. The dietary intakes were measured by using a food frequency questionnaire and one 24-hour dietary recall. There are some problems with these techniques as they’re based on memory. People are often not really aware of exactly what they’re eating which can make precision challenging. Although there were many confounding factors which were accounted for. Smoking, physical activity, family history, supplements, alcohol consumption, menopause and HRT use were a few of the confounders which were taken into account.
So the findings suggest that red and processed meat intakes above 50g and 25g per day (respectively) can increase the risk of bowel cancer…. But what can we take away from this?
1. We shouldn’t categorise both red and processed meat in order to demonise both. As a population we are consuming too much processed meat and should aim to limit it where possible although when it comes to good quality red meat there are some health benefits.
2. Good quality red meat is rich in nutrients such as iron, zinc and B12. Iron found in animal products is much more bioavailable. This means the iron can be more absorbed and utilised than iron from plant-based sources. B12 is really difficult to get from plant sources and so must be consumed from animal sources. Although if you’re following a vegan diet then you may wish to supplement.
3. The research also showed the adequate fibre intake was associated with a reduced risk of bowel cancer. The majority of the population are only reaching around 18g of fibre per day when the recommendations for the daily intake is 30g. Focus on increasing your intakes of beans, pulses, fruits, vegetables and wholegrains to help increase your fibre intake.
Whilst there are no conclusive explanations for the association between red and processed meat and cancer intake one explanation may be due to the nitrates/nitrites. Nitrates/ nitrites are chemical compounds used to preserve red and processed meat. They’re the compound which provides the deep red colour. They have a slow transit time which means they lurk in the bowel and it said that this can increase risk. As a result the high fibre intake speeds up transit time which may be one explanation as to why fibre helps to reduce the risk.
Another explanation suggests that the processing techniques e.g. smoking, preservatives and high heating temperatures may impact bowel cancer risk.
Overall try limiting your processed meats, focus on consuming one portion of good quality meat per week and increase your fibre intake to help reduce the risks associated with bowel cancer.