Mood swings may depend more on perception than blood sugar levels

New research suggests that mood swings linked to hunger or blood sugar changes are not caused by biochemical shifts alone. Instead, how we consciously perceive our body's internal state plays a far bigger role in emotional stability. The findings highlight the importance of interoception—the ability to sense bodily signals—in managing mood fluctuations.

A four-week study tracked 90 healthy adults using continuous glucose monitors. Participants recorded their hunger, satiety, and mood multiple times a day. The results showed that lower glucose levels were tied to worse moods, but only when people felt hungry. When glucose dropped without hunger awareness, mood remained stable.

The study also found that physical factors like body mass index or insulin resistance had no impact on mood changes. Instead, those more attuned to their glucose shifts experienced fewer mood swings. This suggests that emotional reactions depend on how we interpret bodily signals, not the signals themselves. Further evidence comes from interoceptive training methods, such as heartbeat perception exercises and mindfulness. A 2019 randomised controlled trial by Bornemann et al. found that four weeks of such training reduced negative mood fluctuations. A 2021 meta-analysis by Khalsa et al. confirmed moderate improvements in mood stability, while a 2023 study by Forkmann et al. showed these benefits lasted at least six months in non-clinical groups. These interventions work by sharpening interoceptive accuracy, lowering emotional reactivity, and improving emotional regulation.

The research confirms that mood stability is closely tied to how we perceive our body's metabolic state. Glucose fluctuations alone do not directly worsen mood—it is the conscious awareness of hunger or energy changes that triggers emotional shifts. This opens possibilities for training programmes that enhance interoceptive skills to help people maintain steadier moods.