Each week we analyse some of the hot headlines in health and nutrition news. This week: Breast cancer in larger women; vitamin D and arthritis; and health benefits of coffee.
HEADLINE 1: Breast cancer tumours ‘larger’ in overweight women
The BBC, Daily Mail and The Telegraph picked up on a Swedish study which found that cancerous breast lumps are less likely to be detected in overweight or obese women before the tumour becomes large. The suggestion is that they should therefore be offered more regular screening.
Behind the headlines: the Nutrilicious dietetic view
It is unclear for definite why cancerous lumps are less likely to be detected in women with high BMI. It could be because the tumours are growing at a faster rate or it could be that because their breasts are larger, the tumours were harder to find.
Current guidelines for screening in the UK are that all women aged between 50 and 70 are invited for screening every three years. Cancer Research UK have spoken out regarding this study, stating that it does not provide enough evidence to support a change in the guidelines.
In terms of breast cancer prevention, the role of Body Mass Index (BMI) has been recognised by Cancer Research UK, whereby being overweight (BMI 25-29.9kg/m2) or obese (BMI 30kg/m2 and above) is a known risk factor. Although screening guidelines are to remain the same, this study further reiterates the importance of maintaining a healthy weight.
Calculate your BMI
HEADLINE 2: Vitamin D may help prevent rheumatoid arthritis, suggests study
The Guardian reported on a laboratory study that investigated the role of vitamin D in rheumatoid arthritis (RA), following previous research showing it might have anti-inflammatory effects.
It was found that in non-diseased tissue, the immune cells responded well to active vitamin D. In contrast, the tissue from inflamed joints in people with RA was much less effective in responsiveness to vitamin D.
The researchers suggested that vitamin D supplementation may therefore be able to help prevent the onset of RA. They also said that while it is vitamin D is unlikely to be a successful treatment for established RA patients, if there was a route to make the diseased cells respond to vitamin D, then potentially this could help with treatment options. Another suggestion is that vitamin D supplementation may help with the prevention of inflammatory conditions such as RA. .
Behind the headlines: the Nutrilicious dietetic view
This was a small laboratory study that only involved 15 participants and much more research is needed to investigate why the RA cells were insensitive to vitamin D. Although useful in understanding vitamin D in RA, we cannot draw conclusions regarding the use of vitamin D supplements to either prevent or potentially help treat people with RA. The suggestions are pure speculation; there would be a lot more research needed to investigate both of these points
Regardless of the potential effects on inflammation, the UK’s Scientific Advisory Committee on Nutrition advise that all adults and children over the age of one should be taking a daily 10mcg vitamin D supplement during the autumn and winter months (October to March). With our main source of vitamin D through exposure to sunlight, it can be hard to get adequate supplies in these months. Although we can obtain vitamin D from foods such as oily fish, eggs, red meat and liver, sources are limited so supplements are a better way of being sure.
HEADLINE 3: Three cups of coffee a day ‘may have health benefits’
News outlets once again jumped on a ‘healthy coffee’ study, with the BBC, ABC News, Daily Mail and The Guardian picking up on a study which looked into previous research into coffee and health. The researchers looked into more than 200 studies, most of which were observational by design.
Those who drank three cups of coffee per day appeared to reduce their risk of heart disease and of death from heart disease. The most notable benefits were the effects on liver disease and liver cancer, with coffee drinking reducing the risk.
Behind the headlines: The Nutrilicious dietetic view
In last week’s Nutrition News Digest we also reported on a study that found benefits of coffee drinking and reducing the risk of liver cancer.
Although this week’s study backs up recent research, similarly to last week it cannot prove that it is actually the coffee drinking causing the effects seen. There are many factors, including the lifestyle of coffee drinkers, which may contribute to the effects. Moreover, most of the studies included within the analysis were of low quality – as recognised by the researchers.
The headlines focus on the positive aspects of coffee drinking. Although most of the effects were found to be positive in this research, some of the studies also showed a harmful health outcome (e.g. for fracture risk in women).
There is a useful summary of the current evidence into coffee and health in an editorial in the British Medical Journal, Coffee gets a clean bill of health, which discusses the questions many people may be asking in response to these recent headlines, including:
1. whether coffee should be recommended to prevent disease; and
2. whether people should start drinking coffee for health reasons.
Both questions are answered as ‘no’. There is simply not enough sound evidence to make these conclusions.
Nevertheless, the advice remains the same in that a caffeine intake of up to 400mg per day (3-4 cups of coffee) is perfectly safe and that coffee is absolutely fine to include in moderation. Pregnant women should limit their intake to less than 200mg per day (2 cups of instant coffee).
For more information, go to:
NHS, pregnancy and caffeine
EFSA, Scientific opinion on the safety of caffeine