It’s surprisingly hard to say whether devouring a dessert at breakfast actually helps with weight loss. The most reported research comes from a team led by endocrinologist Prof Daniela Jakubowicz at Tel Aviv University in Israel.
In 2012, her team published a study of 193 people on a calorie-controlled diet who consumed either a low-carbohydrate breakfast or one with high protein and high carbohydrate, including a sweet treat such as a piece of cake or a doughnut.
After 16 weeks, the low-carb group started to regain weight while the breakfast treat group lost a few more kilos. The scientists reported that people in the treat group were more likely to stick to their diets, possibly because the foods lost some of their ‘reward value’.
The morning dessert also appeared to reduce levels of the hunger hormone ghrelin and so cut food cravings. In a later book, The Big Breakfast Diet, Jakubowicz explained that the hormones that control appetite, energy and metabolism vary naturally around the clock. She prescribed an early protein-packed breakfast with a sweet treat, followed by a carb-free lunch and dinner with no sweets.
Testing whether such diets work is difficult because people tend to lie about what they eat and trials don’t generally last long enough to see true results. Although there is some evidence that consuming more of a calorie-controlled diet early in the day results in greater weight loss, according to a 2022 review by Isabel Young and colleagues at the University of Sydney in Australia. The human body has ‘metabolically evolved’ to consume more calories earlier in the day, they said.
While a central circadian rhythm is responsible for regulating sleep, body temperature and melatonin production, peripheral rhythms cover metabolic hormones such as insulin and ghrelin.
Should you eat breakfast?
Eating more earlier in the day may help to synchronise the circadian rhythms, so that we feel more in tune with ourselves, they suggested. They also highlighted data showing improvements in blood sugar levels and cholesterol with morning eating.
Meanwhile, a UK review led by Dr Suzana Almoosawi at the University of Newcastle concluded that we still don’t understand whether energy should be distributed equally across the day, or whether breakfast should provide most of it. Evidence from human studies appears to indicate that it’s harder to feel full as the day goes on, potentially hinting at a need to consume a greater proportion of energy earlier in the day, they said.
When they analysed data from the UK’s official National Diet and Nutrition Survey, they found that high-carb eaters, who also consumed more between 6am and 9am than moderate- or low-carb eaters, appeared to be the healthiest.
But they pointed out that those on low-carb diets may simply have turned to fat or alcohol as replacements. Which just goes to show how difficult it is to study human diet.
Read more:
- Fat cells stretch, they don’t multiply: Why everything you know about weight gain is wrong
- The 3 rules your diet needs to actually work
- The fast metabolism myth: Here’s what actually determines how slim you are
- HIIT vs weight training: which will make you fitter, a physiotherapist explains the difference
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