Professor Sarah Berry, a nutrition scientist who specializes in heart health, takes a balanced approach to her diet by focusing on the basics, like eating plenty of whole foods and avoiding refined sugar.
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But recently, she has experimented with tweaking her eating habits. She told Business Insider that emerging data has convinced her that how quickly we eat and at what time of day, could impact the risk of developing chronic diseases.
“This is a really interesting area of research that I’ve found myself in more recently,” she told Business Insider.
Here are three ways Berry has changed how she eats based on current research.
Not eating after 9 p.m.
For a self-professed snacker like Berry, this is no easy feat.
Research suggests that eating late disrupts the circadian rhythm, the biological clock that controls sleep and wake cycles, hormone regulation, and hunger cues. This is thought to negatively impact metabolic health, increasing the risk of chronic diseases, including diabetes and cardiovascular disease.
Studies have also found that eating late into the evening can lead to waking up hungry, she said, which can cause weight gain if we eat more than we typically would.
A meta-analysis published in the journal Obesity Reviews in 2022 found that those who ate the majority of their daily calories earlier in the day lost more weight than those who ate the same amount of calories later in the day and into the evening. The authors said improved synchronization of sleep-wake cycles and daily hormone cycles in the early eaters was the likely reason.
Earlier eating was also associated with lower LDL or “bad” cholesterol, lower fasting glucose levels, and lower insulin resistance, all signs of good metabolic health.
Fasting for 12-hours overnight
Berry tries to make sure she doesn’t eat for 12-hours overnight. A typical 12-hour fasting period for Berry is from 9 p.m. to 9 a.m.
This is a relatively attainable form of intermittent fasting, or eating within a restricted time window, a trend that’s been popular with biohacking bros for years.
It is believed that fasting for around 24 hours or more triggers a process called autophagy, where old, damaged parts of cells are removed or recycled so they function. It optimizes how our cells function, and growing research suggests it may play a role in preventing heart disease and cancer.
However, it’s important to note that most evidence is based on animal studies, and more research is needed to prove the effectiveness in humans. Imposing rules around food can also be harmful for those with a history of disordered eating.
Not eating too quickly
Eating too quickly has been linked to worse metabolic biomarkers, Berry said. So she tries to eat her food “at a reasonable pace.”
We know that if you eat your food too fast, you tend to over-consume, she said, but evidence suggests it could carry greater risks.
A 2021 meta-analysis published in the journal Frontiers in Nutrition involving 465,155 linked eating quickly with higher risks of metabolic syndrome, obesity, elevated blood pressure, low HDL or “good” cholesterol, and elevated blood sugar, compared to those who ate slowly. These are all important risk factors for cardiovascular disease, Berry said.
