Experts say common symptoms like brain fog, irritability and afternoon fatigue could be linked to unstable glucose levels.
According to physician and bestselling author Dr Rangan Chatterjee, feeling exhausted, unfocused or irritable could be a sign your glucose levels are out of balance.
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A survey of 2,000 adults found the average person experiences an afternoon slump three times a week. However, only a small number connect their symptoms to what they are eating.
Could your lunch be causing the afternoon slump?
Dr Chatterjee said meals low in protein and fiber can leave people vulnerable to energy dips later in the day.
As a result, many reach for sugary snacks to get through the afternoon. Unfortunately, that quick fix often triggers another crash shortly afterward.
The health expert, who recently partnered with Abbott's Lingo glucose biosensor and app, recommends prioritizing protein at lunch.
Meanwhile, a brisk 10 to 20-minute walk after eating may also help support healthier glucose regulation.
Research found that more than half of adults experience immediate fatigue during an afternoon slump, while many also report low mood and irritability.
Furthermore, these crashes can affect productivity, encourage unhealthy snacking and even strain personal relationships.
What other symptoms should you watch for?
According to Dr Chatterjee, glucose fluctuations may also affect sleep and concentration. Overnight drops can trigger cortisol surges that wake people unexpectedly.
Meanwhile, daytime dips may leave people struggling with focus, concentration and so-called brain fog.
Instead of reaching for another coffee, he suggests drinking water and eating a small handful of nuts, which provide a steadier source of energy.
Dr Rangan Chatterjee said: "We've normalised feeling exhausted, unfocused and irritable, but these can be early signs that the body is struggling metabolically, and that matters.
"Glucose is one of the most important signals in the body, shaping how we feel day to day, from our energy and mood to our focus and sleep, while also playing a role in long-term health.
"Prediabetes is far more common than most people realise and often develops silently."
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