When it comes to the optimum time to eat carbs , mornings are thought to be best because our body has more time to burn up the glucose released by them and is therefore less likely to store excess amounts as fat.
However, according to a pilot study on last night's BBC programme Trust Me I’m a Doctor, saving them for the evenings could be a better option.
Conducted by medical journalist and intermittent fasting expert, Dr Michael Mosley and Dr Adam Collins from the University of Surrey, the experiment aimed to find out if the body's ability to keep blood sugar levels in check would be affected by the time of day that carbohydrates were eaten.
For the first five days, the healthy volunteers were asked to eat a high carb breakfast (a fixed amount including foods such as vegetables, bread and pasta) and a low carb dinner. This was followed by five days of normal eating and then a final five days of eating low carb breakfasts and high carb dinners. A medium amount of carbs were eaten for lunch during both sets of days.
The results came as a surprise. After the five days of following a programme of high carb breakfasts and low carb dinners, the average blood glucose response of the volunteers was 15.9 units.
However, it was reduced to 10.4 units after the five-day programme of low carb breakfasts and high carb dinners - much lower than the team was expecting. Their ability to process carbs throughout the day had improved.
It could be that what matters is not so much when you eat your carbs but the length of the carbs-free ‘fasting’ period that precedes your meal
The results suggest that a ‘no carbs in the evening’ statement is too broad an approach and that what mattered was the time left in between carb-heavy meals.
“It could be that what matters is not so much when you eat your carbs but the length of the carbs-free ‘fasting’ period that precedes your meal,” Dr Mosley commented in an article for the BBC .
“If you've had a big gap since your last carb-rich meal, your body will be more ready to deal with it. That happens naturally in the mornings because you've had the whole of the night, when you were asleep, in which to ‘fast.’ But our small study suggests that if you go low-carb for most of the day, that seems to have a similar effect.”
Interestingly, the experiment indicates that if you eat low carb breakfasts and high carb dinners for a few days, the body gets used to the heavier carb load in the evenings.
Nutritional therapist Daniel O’Shaughnessy also sees the merits of a ‘carbs in the evening’ approach. He too has found that when combined with a low-carb breakfast, the longer gap between carb-rich meals allows the body to become better able at dealing with carbs in the evening.
“I have been using the ‘carbs in the evening’ approach with my clients and had great success,” he tells us. “The ‘bro science’ [word of mouth] approach of having your carbs in the morning is unfounded. Your body won’t suddenly stop digesting carbs at night.”
A low carb breakfast helps curb cravings later on in the day too. “As soon as you have carbs, you crave more carbs - carbs can cause blood sugar elevations which make us crave more carbs. If you have protein and fat for breakfast, then you don’t get the slump or want something sweet a few hours after.”
He also uses this approach with intermittent fasting for weight loss and has found that they work well together too.
As a follow-up to the show’s provisional findings, Dr Collins is now launching a much larger study. For now though, he advises not stressing too much about when you eat your carbs, just ensuring that you don’t overload them at every meal.
Dr Mosley agrees. “If you've had a lot of carbs in the evening, try to minimise them in the morning,” he says. “On the other hand, if you've had a pile of toast for breakfast, go easy on the pasta that night.”