When I hear people tell me they regularly feel anxious, dysregulated, or on edge, one thing I assess is whether they are consistently eating enough to adequately fuel their body.
In her book, Sick Enough, Dr. Gaudiani explains that when our bodies are not getting enough consistent nourishment, whether from “dieting” and eating disorders, medical issues, or food insecurity, the body shifts into survival mode. In this state, she discusses how many people experience heightened anxiety, irritability, rigidity, emotional reactivity, difficulty concentrating, and sleep disturbances as a direct impact of undernourishment. She stresses that these effects of not eating enough occur in people of all body sizes.
You do not need to look “thin enough” or visibly ill for your body and brain to register an energy scarcity.
A clear demonstration of this comes from the Minnesota Starvation Study. In the 1940s, male participants were placed on a prolonged semi-starvation diet, where for six months, they consumed about half of their normal intake, eating approximately 1570 calories per day to mimic conditions of war in Europe (Keys et al., 1950). Over time, they developed significant anxiety, depression, emotional volatility, social withdrawal, and obsessive thoughts about food, all despite having no prior mental health conditions. These changes emerged as a result of food restriction alone, and many persisted well into nutritional rehabilitation. The study showed that undernourishment itself can create symptoms of anxiety and hyperarousal.
This aligns with what Dr. Gaudiani describes. When the body is underfueled, the brain prioritizes survival over regulation. Fear responses intensify, thinking becomes more rigid, and the nervous system remains on high alert. In this state, just asking someone to “use coping skills” or “reframe anxious thoughts” misses the root issue. An undernourished brain does not have the resources required for consistent self-soothing, cognitive flexibility, or emotional regulation (as cited in Gaudiani, 2025).
This is why no amount of thought reframing or coping skills can fully resolve the dysregulation that is driven by ongoing undernourishment.
Until the body receives adequate, consistent nourishment, the nervous system will continue to signal danger regardless of insight or coping strategies.
If any of this resonates, I highly recommend meeting with a registered dietitian for nutrition counseling alongside therapy. While therapy can help provide the essential tools for long-term healing, consistent nourishment provides the biological foundation those tools need to work. Please don’t hesitate to reach out for help!
