Making sense of… fasting research
In this new slot, I’m highlighting some of the most interesting recent research around fasting, healthy eating and our diets generally.
For my new book, 5:2 Good Food Kitchen, I’ve taken a look at ten of the biggest food myths and big questions that face us all, from Should I eat sugar? to Is it dangerous to skip breakfast? Here in the news section, I’ll be updating that research.
Today… what’s the evidence for 5:2 warding off cancer? And does dining with a ‘fat friend’ encourage us to eat more?
Can the 5:2 diet protect us from cancer?
Could 5:2 diet help to ward off cancer? The Daily Mail Online asked in November 24. The headline was in response to an article by experts from US, British and Belgian Universities
The article looked at different eating patterns:
– caloric restriction (CR) – where daily calorie intake is reduced by 20-40% and meal frequency is unchanged
– intermittent energy restriction (IER) – fasting or greatly reducing calories consumed intermittently; for example, two days a week, as with 5:2
– time-restricted feeding (TRF) – limiting calorie consumption to a 4-6 hour ‘’window’ in your day.
They looked at research on how humans and animals respond to those patterns, and speculated that bodily changes brought about by changing when and what we eat have the potential to reduce the rate of cancer, and other diseases (these might include cardiovascular disorders and dementia). Intermittent energy restriction and limiting your eating to certain time periods might help the body burn fat and repair cells/remove damaged cells.
They suggest that we evolved to eat with longer gaps or intervals, and that our ‘three meals a day plus snacks’ eating culture may be damaging. Plus, of course, the more frequently you eat, the more chances there are to overeat and increase your weight, which is damaging to health: the ultimate unhealthy cycle.
Who was behind the article?
If you’ve read The 5:2 Diet Book, many of those contributing will be familiar to you including Krista Varady and Michelle Harvie, whose pioneering research and trials led to the BBC Horizon programme presented by Dr Michael Mosley, which also featured article contributors Mark Mattson, Luigi Fontana and Valter Longo.
What else should we bear in mind?
The article stresses that more good-quality research is needed, to test the theories that fasting/time-restricted eating is beneficial to health. And the NHS site Behind the Headlines – always a great starting point for reading between the lines, and as they point out, ‘an honest and accurate answer to the question, based on the study, would be “we don’t know”.
I really hope more research will be forthcoming, but in the meantime, there’s a lot to be excited about. At the very least, we know 5:2 can be a highly effective tool or strategy to help people achieve or maintain a healthy weight – and the science behind the potential health benefits is promising. On a personal level I know I’m lighter and more energetic than three years ago, and will maintain this way of life. In a world where we’re being encouraged to overeat all the time, fasting is a brilliant tool for helping us give our bodies a break. There’s a reason why 5:2 is catching on so fast…
do ‘fat friends’ make you eat more?
Fat friends DO make you eat more: Study finds we’re more likely to ditch healthy eating when dining with overweight people the Mail Online told us in September 2014
The report came from an experiment in a US university where an actress stood next to a buffet table – once wearing a fat suit to make her look overweight, and once without, so she looked a healthy weight.
The study showed that the volunteer students ate more spaghetti when the woman was wearing the fat-suit than when she wasn’t – and the researchers, from Southern Illinois University and Cornell University, concluded this could mean that in real life, our food intake is influenced by the size of people we’re eating with, or are sitting nearby.
Environment has a huge effect on why and how much we eat (I talk about the three Es in my book) – and it’s certainly true that friends can egg us on to have ‘one last drink’ or ‘another slice of cake, go on, treat yourself.’ Our perception of what being overweight is, also changes when people we see all the time are heavier or lighter. Plus all-you-can-eat buffets are also a calorie danger-zone – the wide choice seems to make us take and eat more, according to other research.
But this latest fat suit research was small in scale, with only 82 people, all in their late teens. And the buffet table only had two choices – spaghetti and salad! So it’s a big leap from a limited study like that to conclude being near an overweight person somehow gives us permission to eat more… more work is needed.
My verdict: stay aware of what you’re eating, whatever the environment, and follow your own appetite, rather than letting yourself be swayed by other people’s encouragement or comments!
For more analysis and Making Sense of Healthy Eating information, see my new book, 5:2 Good Food Kitchen